Issuu

Volume I

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Issue I

Inside this Issue • Power Electronics … 2 •T Téte-à-Té -T te … 3 -Té • Junction Bipolar … 4 • Chalk n Blackboard … 5 • LED … 6 • Byte This! … 6 • Illuminati … 7 • Know Thy Turf … 7 • Photonic Crystals … 8 • Check ’em Out! … 9 • Spectrum … 9 • Crossword … 10 • Impressions … 10 • loonEEy Toons … 10

The Team Chief Executive Editor Harpreet Singh Chief Editors Shriram Shivaraman Sandeep Sangameswaran CORE GROUP MEMBERS Abhijeet Paul, Aneesh Nainani, Sandhya Hegde, Lalit Goel, Vivek Mishra, Anurag Singla, Gaurav Mittal, Anshu Jain, Nishant Patni

DEPARTMENT OF ELECTRICAL ENGINEERING We shall not cease from exploration And the end of all our exploring Will be to arrive where we started And know the place for the ﬁrst time.

the heavy burden of responsibility that was saddled upon us motivated us to form a dedicated team with a common goal. A lot of planning and effort has gone into bringing out this first issue -- T.S. Eliot of this newsletter. There have been a lot echnology is the cradle of civili- of ideas pouring in from all quarters as zation. In the era of super com- to the way this mouthpiece should be petition and leapfrogging sci- given form. We believe that we have entific breakthroughs, it is invariably done our best to include the best of all the fast and the steady who remain in worlds in bringing out this issue. We the race, if not win it. And as the largest have proposed to keep a definitive undemocracy of the world, India has a lot derlying theme for many of the articles to say in the manner our planet is being included. This has been done with a viled into the realms of sophistication. sion of continuing along similar lines Be it the pure sciences or their applied in the future issues with changes being cousins, India has been long known to incorporated as and when desirable. produce many of the best men in these The comments and criticism of the inareas. It would not be an overstate- terested reader are awaited eagerly by ment to say that the IITs of our nation the editorial team. form the crux of a technologically proIn addition to the copious amounts active factory continuously churning of fun and frolic that you would expect out world beaters. And it is a matter of immense pride that IIT Bombay leads from the front in this aspect. in any issue, the following articles are The right to speech of so potent a proposed to be regular features in the workforce cannot be suppressed. In newsletter. The first of these is ‘Juncfact, it is imperative that every tech- tion Bipolar’, a debate piece, which esnological vocation be given a voice to sentially explores and brings to light express its thoughts and concerns to the two sides of an issue of relevance the world. The case is no different with and general interest. Another regular our very own Electrical Engineering article is ‘Know Thy Turf ’ which aims Department here. The pages of this to put some lesser used lab in the denewsletter are not mere experiments partment under the spotlight and crein ink but are formed from the finest ate awareness about the many facilities chords of technical harmony. Every available there. ‘Chalk and Blackboard’ scintillating piece of technology being presents a rendezvous with a Profesdeveloped in the department has an in- sor. The idea behind this is to enable tense and melodious blend of dedicat- the faculty to express their views on ed and tireless co-operation among a the present scenario in the department lot of brilliant individuals who remain and make the students aware of the in the background. Thus, it would be faculties’ expectations. There are also highly appropriate to say that it is this articles featuring successful alumni very ‘Background Hum’ which has of the department and smart electrisustained our department through the cal engineers who have made a difdecades and taken it to the glorious ference to this world. A feature story heights where it reigns with its entire on some issue of technical interest is splendor today. also included. Articles on some of the Some of you would be aware of core areas of research in this departthe existence of a newsletter with the ment such as Power, Control Systems, same name till not so long ago. It got and Communications etc. with valudiscontinued due to some unfortu- able contributions from the faculty nate reasons. When we set out a few are proposed to form regular features weeks ago, to bring back the forgotten of this newsletter so as to expose stuglory of this mouthpiece, all of us were dents to the various research compewonderstruck by the vision behind the tencies of our department. Besides, name. Added to this was the immense contests like LED and ASIC have been apprehension as to whether we would introduced with a view to enthuse stube able to do justice to this vision as dents to explore various aspects of EE well as to our department. The realiza- not taught in the classrooms. LED or tion of the enormity of our task and “Let Enlightenment Dawn” is all about

Spring 2005

We do not see light, we only see slower things lit by it, so that for us light is on the edge the last thing we know before things become too swift for us. C.L. Lewis

IIT BOMBAY presenting some little-known but hot topic to the public with just enough technical details so as not to sound too much like popular science. ASIC or “Avant-garde Singular Idea Contest” is aimed to bring out original thinking and creative solutions from the students, encouraging them to think outof-the-box. Exciting cash prizes have been proposed for the winning entries of these competitions. The eﬀorts undertaken by the entire supporting team for “Background Hum” as well as the professors who gave their valuable support and contributions are commendable. The editorial team wishes to express heartfelt gratitude to all the core group members involved in bringing out this inaugural issue of this newsletter. Special thanks are also due to the Department Feedback Committee for mooting this idea and also to EESA. The editors are also indebted to Prof. Harish Pillai, Prof. V. Ramgopal Rao, Prof. B.G. Fernandes, Prof. A.M. Kulkarni and Prof. A. Karandikar. Thanks are due to Sudhanshu and Adnan also. The start has been made and the ﬁrst step has been taken. Let us march ahead steadfast with the aim of converting this small step into a giant leap towards the glory of the EE department.

From the Editors’ Desk

FEEDBACK We would love to hear from you. Please send in your valuable comments and suggestions to bh@ee.iitb.ac.in Visit us at: www.ee.iitb.ac.in/backgroundhum

Department G.Sec. Harshad Kasture EESA Council EESA G.Sec. Aneesh Nainani Joint Secretaries Gaurav Mittal Nishant Patni P.G. Nominee Nisarg Shah

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diode bridge rectifier in an adapter used to power a radio scarcely handles power of few tens of watts. Can you imagine a rectifier system rated at 2,000,000,000W? Before we answer a counter question about why we need to have such a large rectifier system, let us tell you that such systems have been engineered in practice. For example, one such huge rectifier, which uses thyristors, converts power generated in coal rich Orissa (using AC synchronous generators rated at 500,000,000W) from high voltage AC (400kV rms) to DC (±500kV) and transmits it over a distance of 1350km to the power hungry Karnataka. At the other end an inverter changes it back to AC. Wait a minute, haven’t we been told that AC systems super ceded DC systems more that a century ago because of the ability to step up AC voltages for efficient transmission? Then why has DC made a comeback - at least in some applications? The answer lies in the physical characteristics of transmission lines.

Powerfor Electronics

Multi Mega Watt Applications Prof B.G. Fernandes and Prof A.M. Kulkarni

in synchronism. (Do you know, that at present a synchronous generator at the generating station at Trombay, runs in synchronism with a generator in Arunanchal Pradesh?) However, synchronous generators connected via long AC lines are susceptible to loss of synchronism due to large phase angular diﬀerences in AC voltages across the line. If generators in an interconnected system lose synchronism, they are electrically separated into islands. Failure to do so in a short time may result in cascade tripping of equipment and even a complete blackout in the grid. Interestingly, power electronics can be used to solve these problems. This

Problems with Long Distance AC Transmission:

end, we have Thyristors, Gate Turn oﬀ Thyristors and Insulated Gate Bipolar Transistors. At the lower power range, devices like MOSFETs are used which are capable of switching at very high frequencies (around 500 kHz).

Application to Power Systems

Capacitive and inductive eﬀects in transmission lines are not seen in steady state for DC transmission. Therefore, DC transmission becomes attractive for long distance transmission. A typical scheme for DC transmission uses a transformer to step up the AC voltages and then rectiﬁes them. High Voltage DC trans-

We all know that electromagnetic phenomena are governed by Maxwell’s equations. As a consequence , it turns Transmission line out that a transmission line can be Fig3: TCSC modelled as a distributed circuit of infinitesimal inductive and capacitive has been made possible by the advent mission is done and the voltage at of high power semiconductor devices. elements as shown below: the other end is inverted back to AC. This causes some unusual effects, esInstead of outright conversion to The Advent of High Power Elec- DC, one may even modify the chartronics acteristics of a transmission line by The Nobel prize winning discovery connecting variable capacitors and inof a transistor and subsequent devel- ductors in series or shunt, to suit variopments in signal electronics eclipsed ous operating conditions. Variation is Fig1: Transmission Line Model the rather modest advent of a four made possible by power electronics. layer semiconductor device called a pecially when line lengths exceed a few thyristor in 1958. This spurred a sechundred kilometers and AC is used. If ond, but quieter revolution called power flows in a long distance AC line power electronics. Power Electronics are lesser than a certain value known used semiconductor devices as switchas the characteristic loading, then over ing elements to control power flow voltages are caused. This may cause much like a valve controlling flow in dielectric breakdown of air around a a pipe. These devices were operated conductor (flashovers). On the other in two extreme states, saturation and hand voltages may sag if loading is too cut-off, from considerations of effihigh. ciency. This heralded a revolution in Another important problem with applications like motor control, where T.L

Fig2: HVDC AC transmission is that one cannot operate a system with synchronous generators running at diﬀerent electrical frequencies, because it causes pulsations in power ﬂows and voltages. Thus, if two generators are connected via an AC transmission path, then they have to run

these options allowed eﬃciency improvement and reduction in size over conventional methods. Power Electronics has found applications ranging from household applications like a fan regulator to spacecraft power supplies. The devices available today can block large voltages (10kV) and allow for large current ratings (6kA) when switched on. At the high device rating

V.S.I

Fig4: Static synchronous series compensator Instead of outright conversion to DC, one may even modify the characteristics of a transmission line by connecting variable capacitors and inductors in series or shunt, to suit various operating conditions. Variation is made possible by power electronics. An other device uses a voltage source inverter (VSI) to inject variable voltage into a transmission line. Considering the large ratings, the challenges in engineering these equipment are immense. The technology in some cases (like HVDC) is well matured, while in other cases, only a few prototypes are in operation.

Conclusions

Power Electronics is likely to play an even bigger role in the basic infrastructure of our country. Some of the equipments which have been described in this article have been implemented in our country, and many more are planned. It will allow greater, ﬂexible and controlled power exchange between various regions. Before we sign oﬀ, it will be instructive to have a look at the High Power Electronics installations in India at the present time.

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hat does e v e r y IITian aspire for? Success! We present to you a success-story from IITB, Raghunath S Iyer, Director of Systems Integration at Nevis Networks Inc., Pune. Raghu Iyer obtained his Bachelor’s degree in Electrical Engineering from IIT Bombay in 1981. Further, he pursued his Masters degree in the Department of Computer Science and Engineering at IIT Bombay. Excerpts from a telephonic interview with him.

you play hard and you enjoy life. You can’t beat the system there. It is positive energy all the time.

Anything freaky, crazy that you did at campus? We used to have our share of ragging and fun. Nothing extremist, I mean if you are thinking about people getting bumped or drunk, I don’t feel that was crazy. Maybe I have grown too old to think of it as crazy anymore. It sounds funny at the time you did it but maybe it is not so funny now. I mean a dare could be, you don’t know how to swim and your friend dares you to swim across Vihar Lake. Or you are asked to go to the ladies hostel and ask How would you describe yourself? I would describe myself as someone somebody out for dinner. I don’t know tempered by experience, someone pas- if these are dares or not. These are assionate about technology, astronomy, pects of growing up. At some point, it appears to be a dare; at some other photography, traveling and music. time, you feel like what’s the big deal What guiding principles do you ad- about it. You grow over it. here to in life? The environment around Think positive; attitude makes a lot of difference, be organized and disci- you is larger than what you plined. Life will be full of difficulties and challenges. You don’t always get are. You can do some amount what you want. The negative way of of picking and choosing. But looking at things is that if something you cannot afford to make it is not to your liking, you try to get out of it. Another way to look is to take up too narrow else you will not the new thing as a challenge and try to be able to learn something do it. This attitude will make you more substantial. adaptable and it will give you the skills that you can apply to other places. Tell us a bit about your hobbies. The environment around you is larger I started trekking at IITB. There used than what you are. You can do some to be a monsoon trek. Given an opporamount of picking and choosing. But tunity, we would like to take a Saturday you can’t afford to make it too narrow or a Sunday morning and go out. Phoelse you wont be able to learn some- tography was something which took thing substantial. Take ups and downs my fancy when I was doing my Masin the positive spirit and you’ll have a ters. I still have the camera I bought good time. when I was on the campus. Besides, I am a music freak and have recordTell us about some significant ings of artists like Pandit Hari Prasad memories of IITB that you hold. Chaurasia, Ustaad Zakir Hussain, Shiv The entire experience is worth reliving. Kumar Sharma, Bhimsen Joshi etc, The IITs have a culture of transparency who came and performed during my that is not found elsewhere in this con- time at IIT. I also enjoy western music, tinent. The facilities are phenomenal. especially Pink Floyd and Dire Straits. Again, as I said, you could look at it I also appreciate Indian classical music negatively and say that IITs are not like and have learnt Veena for more than MIT or Stanford. I have met several ten years. students coming from smaller and bigger colleges in the US. Believe me, the Any reminiscences of professors, somepoorer colleges there are far too be- thing particularly interesting that you hind. IITs are associated with industry; would like to share with us? thus students get a chance of working Oh, there are many of them. In fact, in real-life projects. You could end up even today, I quote them. The toughest doing a BTP closely related to indus- often turn out to be the best. We had try or some current problem. Such an a Prof. who taught us machines and association is rare in the US. In fact, electromagnetism which is difficult to you can count them on the fingertips. visualize. You had to see students in Non-academic activities like sports, other colleges to know the real value hobbies-development or the cultural of his lectures. We had Prof. Kamath events are also encouraged a lot in IIT. who taught us twice to pull us out of If somebody today says, ‘Ok Raghu, our bad grades and both were interestwe’ll take care of your living for the ing in their own way. Then there was next five years. What would you like to the infinitely patient Dr. K.C. Mukherdo?’ Then, I would go back to IIT and jee from the communications departenjoy life there. There you work hard, ment. He used to set such a paper

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that if you managed to get a CC, you would feel good about it. Then, I did a lot of projects with Prof. Rao of the CS department. He created a very fertile environment for you to blossom. I remember fondly Prof. Isaac, the then HOD of CS department. In the EE department, we had Prof. Agashe and Prof. Narayan, very good teachers who taught us to get interested in class. Do you still keep in touch with the friends you made in IIT? Yes, it is one of the best networks in the world that you can have. I can recollect the names of 50% people of my batch. I am in touch with 20%. We mostly know where each one is. The batchnetwork helps in later life. You then know its value. What prompted you to take up a job and not pursue a PhD? Even pursuing masters was a big question mark. If you are looking for an academic career, it is doctoral research that you should be doing. But if you want to pursue a job in the industry, I think a Masters is adequate; you better focus on building a career. If you continue to do doctoral work and then join a job, the value of the doctoral work is not so high because the industry doesn’t want solutions to problems that might arise within the next 50 years; it wants so-

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I like to solve problems but I like to see them solved today and see customers beneﬁting from it. I could solve an abstract problem in any domain and if its impact cannot be felt today, it doesn’t give me as much a pleasure as solving one that would impact people within the next 5 yrs.

built I/O controllers, firmware and hardware. While doing this, Prof Rao with his engagement in industry got a project from Godrej. I naturally got involved in it. In 1993-1994, this division began developing electronics resulting in products such as dot-matrix printers, electronic typewriter and later, on their own. Customer problems forced us to go back and improve engineering. The division grew from 2025 to 100. Times were changing. The division had to go through a transformation. One of the fallouts was that part of the division spun out as a different company. I opted to work with the spun out part. I headed one of the three subdivisions. The company started seeking overseas customers. I had to go to California. After a year there, we realized we should do something in the products world. We came upon a technology called Classification which would help networking devices to traffic engineering well which could boost their performance speed to gigabytes. It became successful. I now decided to come back. Then I joined Nevis Networks. So, how did you decide about pursuing networking? In the earlier part of my career, it was mostly hardware and firmware. Geometric software was the place where I did pure software. I was the only guy in the team who knew hardware. So my second role was that I became the IT administrator, putting machines on everyone’s desktop. I learnt networking that way.

What kind of experience did you have at IIT that made you qualify your ﬁrst job? The projects with Dr. Rao. Again, I keep on repeating-do what you have in your hand and do it well. That’s the only weapon you have with you to convince somebody that you are a good candidate. If you screw up your lutions to problems that are imminent academics, you have lost it. Academics i.e. might arise within the next 2 to 3 are nothing but a large assignment. It’s yrs. I like to solve problems but I like an opportunity you are given to learn to see them solved today and see cus- something and do something with it. tomers beneﬁting from it. I could solve an abstract problem in any domain What’s the secret of your success and and if its impact cannot be felt today, it what principles do you hold as a didoesn’t give me as much a pleasure as rector of Nevis Networks? solving one that would impact people I am enjoying life. I can’t say beyond within the next 5 yrs. that. There’s a big success here. The secret is that there Tell us how you started your career is no secret. Just and what paths it has taken. be passionate. While working under Prof. Rao, I had Don’t give your to play the parallel role of a project 100%; give your manager and an M.Tech student. We 200%.

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The Oriental Perspective

nowledge is power and every ambitious student who wants to excel as a technocrat, researcher or professor should definitely aim for a doctoral degree from a reputed university. In a nutshell, a Ph.D. student or research scholar (RS) reads research papers in his chosen field, formulates a new problem, obtains theoretical and/or experimental results, publishes papers in international peer-reviewed conferences, has his thesis reviewed by four professors (one from abroad) and finally defends his thesis. It is very important to realize why one wants to do a Ph.D. Some students are sure about this during their B.Tech. or M.Tech. years, while others spend some time in industry, realize what the “real world” is and then come back. Either way, life is different as a Ph.D. student. One has to be highly self-motivated, think independently and minimize “garbage collection activities”. The journey is far more important than the destination. During the Ph.D. program, one’s perspective to problem-solving changes by orders of magnitude. At the outset, let me emphasize that it is wiser to do a Ph.D. from IIT/ IISc than a “non-top 25” university in USA. Let me now focus on the merits of pursuing a Ph.D. in IITB, esp. in the EE dept. IITB is one of the few technological universities in the world which has departments in all the pure sciences, all the important branches of engineering and more recently, even schools of management and information technology. There is scope for interdisciplinary work - for example, in nanoelectronics. The EE dept. is one of the few in the world which has excellent and cooperative faculty in communications engineering, microelectronics, power electronics and power systems, controls and computing, and electronic systems. Other hallmarks of a good Ph.D. program are “library” and “labs”. Our central library subscribes to all IEEE and Elsevier journals (since 1960) and stocks the proceedings of important conferences and the best books in any field. In fact, if a book (foreign edition) is required for your research and is currently unavailable, your advisor can request the library to acquire it - this process takes at most 3 weeks. Most of the labs in the department have been renovated, have ample computational facilities/engineering equipment

 �� Bipolar  and are air-conditioned. While it is true that we don’t have state-of-the-art equipment in few labs, this is mainly due to limited funding from the Indian industry. However, the symbiosis between academia and industry in India has been growing rapidly in recent years - this will deﬁnitely go a long way in making IITB a world-class research institution. Consider the fact that we have done very well for an institution which is not even 50 years old, while MIT is around 140 years old. Let me now take a slight detour and comment on the quality of research at IITB. The hallmark of any highly successful company or institution is its ability to attract and retain talent. It is high time to implement certain measures to make IIT a world-class postgraduate institution. In comparison with a top-25 university in the USA, what IITB lacks in is not the quality but the number of M.Tech. and Ph.D. students. A larger research group leads to more motivation, more technical disc u s s i on s , better critique and consequently higher quality research output. IITB should also introduce post-doctoral fellowships to attract recent Ph.D.’s from IITs/IISc and abroad. Post-doctoral fellows can supervise the progress of current Ph.D. students and can also be inducted as faculty in due course of time. This can only be achieved with increased funding from the industry and the central govt. In a Western country, a Ph.D. student has to live in a 2-bedroom apartment with 3 other students (which can be hassling), cook his own food and own (thus maintain) a car. If you compare that to IITB where one can stay in H12, eat good mess food and cycle in the campus, a lot of time and energy can be saved. The winters in western countries are usually harsh and outdoor physical activity is at a minimum - compare that to IITB in which the winter months are the best for jogging! To sum it up, what matters in a Ph.D. is what and not where. That is, the appraisal of Ph.D. work depends on the individual’s publications and thesis, and not on the institution which granted him the degree. A Ph.D. student is motivated by the desire to learn and assimilates the knowledge in his ﬁeld both in breadth (while hunting for a topic) and in depth (by solving his newly formulated problem). The academically-inclined reader is requested to carefully weigh his options and eventually consider joining his alma mater for the Ph.D. program.

Dheeraj Prasad Singaraju a.k.a Golu, obtained his Bachelor’s degree from EE, IITB in 2004. He is currently pursuing his Masters and Ph.D. in ECE Dept. at University of Maryland, Baltimore, USA.

ome 7th semester, there is a certain group of students who decide that they would like to pursue further studies and start researching the various places they could go for this purpose. A list is finally prepared and with the extreme rare case, it is not surprising to find any one of the IITs featuring in the list. This makes me ponder over whether the question of the hour is really ‘Do students want to pursue PhDs abroad?’ or ‘Do they NOT want to pursue a PhD in an IIT?’ Before I begin my answer to this question, I would like to make a disclaimer that some sentences might hurt the sentiments of some people (though definitely not intended), but then this is what I feel and need not be the general opinion.

Ph.D : In India or Abroad?

One may reason that a person might not like to continue his/her PhD at IIT is that he/she, having already spent 4 years in undergrad primarily, needs a change of environment and would get more exposure by a change of institution. But then, that raises the question as to why not shift to another IIT to pursue a PhD.? What is it that places the foreign universities high above the IITs for graduate studies? I think that all of us will definitely agree that there is this part of us that wants to travel new places and explore new frontiers. Other than this, what are the factors that make us apply abroad? Better advisors? Better facilities? It is very easy to see that the issue is not regarding advisors as we ourselves have seen that the professors at IIT are definitely up there with the top. So, this brings us to whether the issue is regarding facilities. Consider a person like me working in the area of computer vision. All I need is a computer and a camera which are readily available in the SPANN lab. So, am I justified in saying that I have come to the US for better facilities ?;) In fact, I believe that the microfabrication lab at IITB is as equipped (if not more) as the fab labs in most of the top univs in US. In short, it would only be right to say that IITB has great facilities for most of the areas of research. So, what is it really that makes us migrate to foreign univs ? One area where foreign universities

The Occidental Perspective

Ashutosh Gore obtained his B.Tech. degree from EE, IITB in 1998, and then studied and worked in USA for 4 years. He is currently in 3rd year of his Ph.D. in the Department of Electrical Engineering, IITB.

score over IIT I feel is the exposure. Since, one would be working with (probably the best) students from all over the world, one gets exposure to different styles of teaching, different trains of thought and temperaments which is very important for a successful PhD. I also think that it would be right to say that the professors in IIT are not as ‘active’ in research as in the universities abroad. Then again this is due to several reasons that professors at IIT tend to give greater importance to teaching while it is not surprising to find a professor (in the US atleast, I cannot vouch for the other places) not teaching any course. The fact that these professors can channel all their resources towards research is definitely a positive factor. Having spoken about the factors favouring the foreign universities, I think it is important to mention that a major deterrent for a PhD in IIT is that there is this general feeling (urban legend?) that the PhD program at IIT isn’t good. Well, if I am given the luxury to call us IIT undergrads the ‘cream of the crop’, how can one expect great research to be done at IIT when the cream is doing research elsewhere? This statement might sound very high handed but I do feel that there is a certain amount of truth in it. It is all a vicious circle. The quality of research will definitely tend to improve if the smarter students continued in IIT for their PhDs, but the thing that would probably scare them is the prevalent quality of research. One way we can possibly improve the situation in IITs in the future is to fund research in IIT. The biggest advantage that the US universities have over IITs is that they have institutions like National Institute of Health (NIH), National Science Foundation (NSF) etc. to fund projects. If the IIT’s can imitate such funding institutions by diverting part of the alumni funds into projects we can get better research done. Also, incentives can be given by funding the students to go to international conferences to meet other groups working in the same area. Such an effort can attract B.Tech/Dual students as well to do good research and get publications out with the incentive that they can go to conferences abroad. This will not only add to the student’s CV but also increase competition among students, thus increasing the standard of research in IIT. In the last 8 months I can say that I have had a very satisfying experience in my university and if asked to make a closing statement I would say that one should definitely consider pursuing a PhD abroad. However I also do believe that we should return to India after completing our PhDs (and probably teaching/working for a few years), but then I think that is a topic of discussion for another issue ;)

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rof. Abhay Karandikar is a faculty in the Communications Engineering division of our Department. He joined EE, IITB in 1997. Very recently, he has launched a start-up Eisodus Networks. Excerpts from an interview conducted by Abhijeet Paul:

in the department speciﬁcally under you? I have worked with Texas Instruments (TI), Cirrus Logic, Sasken Communication and SwitchOn Networks. Also, I have done consultancy work for industries like L&T Infotech and Tata Infotech. Besides, I have had projects from agencies like DST, MHRD etc.

We have heard a lot about your startup Eisodus Networks. What role do EE students play in this? We do not have any students working for our startup. Currently, we have What prompted you to choose com- full time employees, most of them EE munications engineering as your ﬁeld graduates from IITB. Basically, ours is of interest? Tell me about your past a purely technology development company and not a company involved in academic background. I had developed my interest in Com- developing some application product. munication Engg during undergradu- We are focusing on developing techate years only. I completed my Ph.D. nologies in the area of broadband Infrom IIT Kanpur. After that, I worked for CDAC in PARAM 9000 supercomputing group. What are your major areas of interest in communications engineering? My areas of interest are currently communication networks and wireless & mobile communication. In communication networks, the main emphasis is on QoS, resource reservation and control problems. In Wireless communication, focus is on QoS in wireless networks - both packet radio networks as well as CDMA based mobile communication. What are the projects that are currently being guided by you? Most of the current student projects are in the areas of wireless communication. In the past we have worked on QoS in Internet, packet scheduling algorithms, resource reservation schemes, admission control and traﬃc modeling.

munication networking jobs, where people with expertise in electrical engineering and having communication background work on projects. In that sense, students and EE graduates who

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For the coming few years F the UG program may continue to be emphasized unless we upgrade other institutions (RECs, NITs) to that level. Then, we can transform to a pure research institute. The ideal thing would be for IITs to become pure research institutes and have the NITs for UGs.

at IITB, but entrepreneurship is also gaining government level recognition in terms of programmes for promoting entrepreneurship at IITs and translating technical ideas developed in IITs into successful commercial ventures.

What difference do you see in the research aptitude and projects of the students today and 10 years back? Personally, I feel students have always been the same. However, some faculty members do feel that there is decline in the standard of students. There may be some element of truth in it. One thing is that decline had happened primarily due to the societal changes. The changes in societal values are bound to affect all walks of life. Second thing is that JEE is highly competitive. People slog in their 12th Std., as a result, when they come to the first yr, they are completely exhausted. So they don’t have enough energy left in their 4th and final year to contribute. Third reason has something to do with the studentfaculty interaction. It is not happening on a regular basis as it could, probably due to the increase in the number of students per faculty (at-least in departments like EE). However, I are interested to work in core commu- feel that given the students’ potential nication and networking are required. they can do a lot better than what they Very few core Indian companies like could do some 20 yrs back because the this exist. A few prominent ones are infrastructural facilities, interaction Tejas networks and companies incu- with the industry and number of projects have definitely increased. Student bated by IITM. should exploit these to their advantage Many ideas come up in our EE de- and show more interest in research. partment, however very few evolve as startups. According to you, what are How can this scenario be changed? I do feel that for the coming few years the main ingredients for a startup? Three main things are needed for a the UG program may continue to be startup; one, you should have a prod- emphasized unless we upgrade other uct idea which should have some value institutions (RECs, NITs) to that level. proposition to the customer. It cannot Then, we can transform to a pure rebe just a research idea or research prod- search institute. The ideal thing would uct. Second thing is the competence of be for IITs to become pure research the team. Fortunately, we have very institutes and have the NITs for UGs. competent people. I would say that But the only question is whether NITs some of the best M.Tech people from can deliver the quality that IITs are deIIT Bombay are in our company. The livering. third thing that you need is resources in terms of funds and other things. According to you what’s the next big thing in the field of networking? What do you think about a depart- As you know Internet has transformed ment-supported startup program? the entire world and the way we live toPreviously IIT Bombay had a KReSIT day. In some sense, a new world order business incubator. Now it has a for- has been set. The next big thing is going malized body called SINE (Society for to be a networking infrastructure that Innovation and Entrepreneurship. The enables anytime, anywhere computing institute support is coming from SINE and communication with robust seand IITB directly. All a department can curity. This is going to fuel research in do is facilitating as they have done in low cost, energy constrained wireless my case: I have been on leave for one devices, a framework of security and year. SINE plays a much needed sup- faster and reliable transfer over wireportive role for startups. Earlier the in- less. There are still many challenges cubator was only for communications that need to be and information technology. But now addressed in the it has been extended to all branches of area of wireless engineering. Apart from infrastruc- networking. ture, it is also giving some kind of seed loans for incubatee companies. Not just

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Three main things are needed for a startup : a product idea having some value proposition to the customer, a competent team and resources in terms of funds and other requirements.

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ternet access; more speciﬁcally we are developing Ethernet based broadband access product which will eventually conform to the new emerging standards of Metro Ethernet (ME) forum. There exists a team for hardware designing, a team for embedded software and a team for network management Which industries support research solutions (NMS). These are core com-

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Winning Entry

don’t know how to do this on a small scale in a practical way, but I do know that computing machines are very large; they ﬁll rooms. Why can’t we make them very small, make them of little wires, little elements and by little, I mean little. For instance, the wires should be 10 or 100 atoms in diameter, and the circuits should be a few thousand angstroms across... there is plenty of room to make them smaller. There is nothing that I can see in the physical laws that says the computer elements cannot be made enormously smaller than they are now. In fact, there may be certain advantages. – Richard Feynman (1959)

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approach to tal efforts in the molecularmolecular elecscale memotronics arena ry is to store began as early charge at moas 1970s with lecular level. the work of AviUt i l i z at i on ram and Ratner of oxidation [1], proposing a states of indisingle molecular vidual molerectifier. They cules is one approposed that, proach being to show rectification, an organic Fig2: Reading and writing in Porphyrin researched on. This approach molecule should have roughly the properties of a p-n also has the advantage of multibit storjunction. By the use of aromatic sys- age within one molecule using multiple tems, it is possible to increase or de- oxidation states. Porphyrins are one crease the pi electron density within such example of memory molecules Electronic technology has rapidly the organic molecule, and therefore [3]. Each porphyrin molecule can be evolved during the past decades. The emphasis is to make better, faster and smaller electronic devices for application in modern life. The contemporary advanced silicon chip can store 16 million bits of information within an area less than 1 cm2. Pentium 4 chip contains more than 50 million transistors. However, there is a practical limit to the scaling. It will soon reach physical and technical limits, inspiring Fig3: Structure(A) and Energy diagram(B) of the switch. Oxidation states the development of new tech- are marked with dotted circles. Diagonally stripped areas are tunneling nologies. Molecular Electronics barriers. Thick barrier is Al O passivating layer & thin one is Ti-rotaxane 2 3 is being seen as potential stakeholder interface. for the same. Molecular electronics can be de- create relatively electron poor(p-type) robustly and reversibly oxidized with fined as technology utilizing single or electron rich(n-type) molecule sub- up to two holes stored as illustrated molecules, small groups of molecules, units. Fig. 1 shows such a molecule. in I-V characteristics of the porphyrin carbon nanotubes, or nanoscale metal- The part of molecule joining the donor (Fig. 2). (Note that porphyrins are of lic or semiconductor wires to perform and acceptor, has sigma bonds, pro- many kinds and this is valid for only electronic functions. Some have de- viding internal tunneling barrier from some special kind of porphyrins.) The two waves correspond to the formadonor to acceptor. The rectification behaviour can be tion of the monocation and dication. explained in detail by examining ener- Charge is stored (written) to the porgy-level diagrams for the system. The phyrin molecules via application of a difference in positions of Highest oc- voltage step, that is set at an oxidizing cupied molecular orbital(HOMO) and potential. Switches are the basic elements of Lowest unoccupied molecular orbital (LUMO) of acceptor and donor groups control in any electronic architecture -by its very function it either allows Fig1: Example of rectifier molecule gives the rectification behaviour. Information storage is an impor- current to flow or not. There are many fined it as technologies utilizing only tant part of the electronic world today. examples of proposed molecular and single molecules, but this definition Similarly, nobody can think of moving atomic switches, which use a variis far too limiting. From the broader to the world of molecular electronics ety of mechanisms of operations. The definition, it can be suggested that any without molecular memories. The ba- development of a molecular switch device utilizing molecular properties sic paradigm for electronic informa- is perhaps the single most important is a molecular electronic device. tion storage is retention of charge in a element in developing molecular reThe first theoretical and experimen- capacitor. So the most straight forward placements for conventional inte-

Hydrogen - the next fuel for separate from the liquid fuel. The hy- Bluetooth controlled camera on wheels drogen then moves to the fuel cell in which can be controlled by the joystick laptops? A New Jersey ﬁrm, Millennium Cell, is developing an 8 hr hydrogen fueled cell battery. The battery works by initially storing sodium borohydride as a solution in the cartridge. This solution passes through a fuel pump and moves into a catalyst chamber, which triggers a reaction. The reaction causes hydrogen to

the laptop, where it mixes with oxygen. or keypad on a mobile phone. The Oxygen enters the laptop through a se- Motion Cam ROB-1 can rove up to a ries of perforated holes in the laptop distance of 50m from the user while streaming video to the phone’s display and individual photos can be taken. The device having an onboard memory casing. This reaction of hydrogen and and measuring 110mm diameter has oxygen creates electricity. three wheels and can move forwards, backwards, look around corners, pivot Roving camera controlled by on the spot and tilt the camera.

Byte This! Bluetooth

Sony Ericsson has demonstrated a Compiled by Gaurav Mittal. He can be contacted at gmittal@ee.iitb.ac.in

grated circuits. There have been several significant suggestions of complex switching behaviours, which include use of arrays of switches to implement logic operations and the use of twoterminal resonant tunneling devices to do the job of switching. A number of examples of molecular switching have been proposed based on quantum effects; single molecules, carbon nanotubes and quantum dots or nanoparticles have all been found under the right circumstances, to display some of these quantum effects. An electronically (singly) configurable junction that consists of a molecular monolayer and a tunneling barrier (redox active rotaxanes) sandwiched between metal wires is shown in figure 3. This junction can be used as a switch and several devices, fabricated in a linear array structure, could be used as electronically configurable wired logic gates. As roxatane molecule shows different energy level in normal and oxidized state, there are two states and the switches are irreversibly opened by applying oxidizing voltage across the device. Tunneling does not occur in oxidized state, hence oxidation opens the switch. The on and off currents differ by a substantial amount. [Fig. 4] Furthermore, these switches can be used to construct (once) programmable molecular logic arrays.

Fig4: I-V characteristics of the switch There is a great promise to molecular electronics – electronics that is smaller, faster, more efficient and potentially more flexible than conventional electronics. Clearly, some visible, fundamental demonstrations have been made of molecular-scale electronic device behaviours. However, it’s still a long way of experimentation and research before molecules will find their place in commercial electronics. References [1]A. Aviram and M. A. Ratner., Chem. Phys. Lett., 29(2):277–283, Nov. 1974. [2] C.P.Collier et. al., Science, 285:391– 393, July 1999. [3] Zhiming Lu, Amir A. Yasseri, Jonathan S. Lindsey, and David F. Bocian., Science, 302:1543–1545, Nov. 2003. (All images courtesy IEEE papers) Saurabh Goyal is 4th year DD(Microelectronics) student. He can be contacted at sg@ee.iitb.ac.in

Illuminati

“W

hen I fully understood the power of Suhas’s software, it hit me like a ton of bricks that his design approach could be the basis for a new kind of Chip Company. I could see the opportunity to get complex chips out in just six months using system designers who didn’t require knowledge of silicon”, said Mike Hackworth, chairman of Cirrus Logic. Hackworth joined hands with Dr. Suhas Patil to found Cirrus Logic. He wrote, in the same book that Cirrus Logic “rocketed to a billion-dollar-ayear rate faster than any other Silicon Valley semiconductor ﬁrm that ever made that climb”. Today Cirrus Logic Inc. is a leading manufacturer of advanced integrated circuits for multimedia, communication and mass storage in personal computers. And the one idea behind this success was that of Dr. Suhas Patil. Hailed as one of the most erudite technopreneurs in Silicon Valley, he had a very humble beginning. He was just a child with a fascination for tinkering with objects, especially those around his house. His father had a side business of repairing radios. This gave him a lot of things to work on - wooden, metal and ﬁnally electronic. He remembers with fondness the Mechano set he played with.

Suhas Patil

enough to see how one could actually ‘manufacture’ gas. He came to solution - crack petrochemicals to create gas. He built an apparatus to take kerosene, crack it to make gas, so that he could have a Bunsen flame. A ‘ridiculous’ attempt in his own words, with an obvious result - the apparatus caught fire. Not satisfied, he tried to lift it once it caught fire and ended up burning his fingers. Dr. Patil did B.Tech (Hons.) from IIT Kharagpur in 1965, Master of Science in electrical engineering from MIT in 1967 and Doctor of Science (EE) from MIT in 1970. From 1970 to 1975 he was Assistant Professor of EE at MIT where he also served as Assistant Director of Project MAC (Multi-Access Computer), the largest computer science laboratory in the US where time sharing system was developed. From 1975 to 1980, Dr. Patil was an Associate Professor of computer science at the University of Utah. Dr. Patil’s research here reached a stage where “either somebody had to adopt it and take it further”, he once told an interviewer. He further said, “But it was so different that industry didn’t want to pick it up. There was too much gap between what I was suggesting and what the normal practice was in the industry. So I couldn’t give it away!”

During childhood he got very interested in chemistry. Since the lab at school wasn’t enough for him, he decided he should have one at home. So he started to ‘create’ a lab of his own. That somebody happened to be The Bunsen-burner needed gas, but General Instrument Corporation. there was no gas at home. So he read With that funding, Dr. Patil completed

he PCB lab, which received a facelift in the recent past, is one of the lesser known labs in the Department. Anurag Singla explores this rather obscure laboratory located in the Annex.

work on software that automated VLSI design. The technology permitted even those not trained in silicon technologies to design integrated circuits in six months, a revolutionary step in 1980s.In 1981 Dr. Patil started Patil Systems Inc. based on his academic research. In 1984 he founded Cirrus Logic with Hackworth. Cirrus Logic has, since then, grown to be a major semiconductor company developing, manufacturing and marketing ICs for personal computers, communications and consumer electronics.

ciation of Indians in America and is a member of the Board of Overseers of the Computer Museum. In 1995, IIT Kharagpur conferred an Honorary Doctor of Science degree on Dr. Patil for his work in science and industry.

Dr. Patil has worked in the fields of computer architecture, parallel processing, mathematics for computer science, design methodology for VLSI circuits and integrated circuits design automation software. He has over 40 scientific papers covering these areas In 1992, Dr. Patil, toof research and has several patents in gether with other sucthe fields of Intigrated Circuits to his cessful entrepreneurs credit. and businessmen of Dr. Patil feels his education has Indian origin in the played a major role in his success. He Silicon Valley, formed a non-profit organization feels a doctoral program is the perfect called TiE (The Indus training if one wants to start a comEntrepreneurs) to assist pany. In his words, “You can finish upcoming entrepre- your undergraduate degree by simply neurs in their endeavor. presenting what is very well learned in Dr. Patil was elected its a very efficient manner. You go to the first president and un- master’s thesis under very strong guidder his leadership TiE ance. The doctoral thesis is all unchartbecame an effective and respected or- ed territory. And this is a very arduous, ganization nurturing and mentoring taxing process. At that point, you have entrepreneurs. Cybermedia, with their to learn not only to do the science but software for automatically fixing per- also to cope with disappointment how sonal computers is one such example. to handle yourself as a person and In fact, Dr. Patil has personally been a how to pick yourself up even when mentor to Cybermedia and is a mem- something doesn’t work. Deal with the blues. And going through that human ber of its Board of Directors. process, you learn a lot. It’s a pity that He serves on the boards of many not many people understand this ascompanies such as RightWorks and pect.” Aspirian Inc. He is also the chairman of Cradle Technologies, Tufan Inc., Navin Communications and Reez. The above success story was compiled com. He is also on the board of com- by Lalit Goel. He can be contacted at munity organizations like the Asso- lalitgoel@ee.iitb.ac.in.

The most signiﬁcant addition is the Rapid Prototyping PCB Fabrication setup. There are essentially three machines involved in this technique. The MiniContac II (LPKF -German made) is a galvanic through hole plating system. It executes the job of PTH (plated through-hole, i.e. metal plating on the wall of the hole) through electroplating. This process norgraded with grants mally takes 2-2.5 hrs. from DST (Central The through-hole platGovernment Entering is an important deprise) in July 2002. The sign consideration for overall expenditure a double sided board, was about 1.6 million which can allow the rupees. The expenses fabrication of more post-renovation are being borne solely complex boards while signiﬁcantly reby IITB. ducing the number of vias. The through holes meet the highest requirements. What new facilities have been intro- The next machine down the order is duced since renovation? the ProtoMat C60.This accomplishes

ted in the lab. Personal work is not catered to in the lab. However, jobs are accepted during Techfest period, but again, they need to be approved by a Who are the people involved in the Professor. The serviclab? es are free of cost and Prof P. C. Pandey is the Professor- no GPBs (General in-charge. The technical staff, which Purpose Boards) are includes Mr. Edward Misquitta, Mr. needed beforehand. Vidyadhar, Mr. Kamble and Mr. R. S. Kedare, is responsible for managing the How was the renovalab’s entire gamut of activities ranging tion of the PCB lab from taking in application forms from funded? students to delivering the final PCBs. The facility was upWhat are the departmental bylaws/ procedural guidelines regarding the lab usage? PCB lab is the only lab in the EE department which can boast of a central facility, i.e., students from any department can make use of this infrastructure very easily. To take advantage of the services, a form available with the lab attendants needs to be duly filled in, signed by a Professor and submit-

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the part of drilling and milling which essentially involves boring holes and carving out the tracks. An extremely precise, reliable plotter head moves over the board area boring holes and carving tracks in a motion governed by a computer program. The computer interacts with the machine with a driver program called BoardMaster. Data required to drive the plotters is generated in-circuit CAM and is stored as ﬁles in GERBER format. The distance between two tracks is usually 0.2mm and diameter can be as small as 0.6mm. The circuits are usually prepared in conventionally available software like Eagle. The maximum size of PCBs that can be made is A4. For making PCBs of more than two layers, LPKF Multipress II is used. It can make upto six layer PCBs in-house. This is achieved by subjecting the PCB to a pressurized (6 bar) oven with temperatures of the order of 250°C.

( c o nt i n u e d on Page 8)

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t was the second exasperating call that I had received. Yet another group of theorists were saying that my discovery did not work. That was distressing. I had spent three long years trying and discarding countless deigns to arrive at what I thought was success, but if the theorists were right, I had to go back to the lab and continue searching. And maybe what I was trying to create - an artificial structure that could manipulate beams of light in the same way that silicon and other semiconductors control electric currents - was not possible at all. - Eli Yablonovitch Scientific American December 2001 The Seeds of a Revolution: Birth of Photonic Crystals The microelectronic and telecommunication industry saw a revolution with the evolution of semiconductors such as silicon, which provide an elaborate control of electric currents. The control is achieved through the band gap property of the material, a range of energies in which electrons are prohibited from propagating. The silicon revolution led to the birth of transistors and Integrated Circuit(IC) technology, which revolutionized the world of Computing, Communications and Information technology. But by the late 20th century, electronic designers had almost realized the theoretical limitations of the speed and bandwidth possible with this technology and the quest for an alternate solution was urgent. Photonics was a solution. Photonics uses photons or light in the visible and infra-red region for carrying information. By shifting to frequency ranges much higher than radio and microwave frequency, it promised a greater bandwidth. With the invention of Lasers in 1960s and the optical fibers in the 1980s, photonics had started making its presence felt. However there was an immediate need for some kind of material which would act as the semiconductors of light and make possible the control of photons in a way similar to the control of electrons made possible by semiconductors. This quest led

Know Thy Turf

�� the photonic crystals that leads to the to the discovery of photonic crystals. It happened in 1987 at the Bell photonic band gaps. However there is Communications Research. Eli Yablo- one major difference between the two. novitch, working on making telecom- While in semiconductor crystals the munication lasers more efficient, was periodicity is restricted to atomic disseeking periodic dielectric crystals tances; for the photonic crystals, this which would exhibit band gap proper- periodicity is scalable and in the hands ty very much like the band gap proper- of the manufacturer. Thus by scaling ties arising in atomic lattices of silicon the periodicity the crystals, the band and other semiconductors. A typical gaps can be obtained in radio and miexample of such a material would be crowave frequencies as well. The Revolution Anticipated: Apa block of special glass drilled through with a closely spaced array of cylin- plications and Vision drical holes, each with diameters in It is now learnt that band gap structures are also found in the range of hundreds of nature - in the sparkling nanometers. Light entergems of opal, the colorful ing this holey material will wings of butterfly and in undergo reflections and the hairs of a wormlike refractions at the myriad creature called the sea interfaces between air and mouse. A large number the glass. The complex of photonic crystals, with pattern of overlapping periodicity in one, two beams will reinforce or and three dimensions cancel each other dependHoley Fiber have been fabricated in ing on the wavelength of light. After struggling for almost four labs all around the world and have years by designing crystals with vari- found applications in diverse fields. ous permutations and combinations of Photonic Crystal Fibers(PCF): 2D periodicity and symmetry and drilling band gap material which restricts light more than 500,000 holes through vari- of a given frequency from travelling ous dielectric materials, Yablonovitch in a plane can be stretched along the and his team demonstrated the first third dimension to form a new kind of successful photonic band gap crystal optical fiber. Electromagnetic modes in 1991. That particular crystal struc- in these fibers would be guided due ture was christened Yablonovite and to the photonic band gap effect rather such materials in general came to be than total internal reflection. The losses and dispersion effect are minimized known as photonic crystals. The photonic crystals are function- in these fibers. These micro structured ally very much analogous to the semi- fibers, known popularly as holey fibers conductor crystals. In semiconduc- have already gone commercial. tors, the Schröedinger equation for Channel waveguides: By removing the electron wave function is casted rows of holes from an otherwise unias an eigen-value problem; in photon- form pattern a line defect is created. ics, it is the Maxwell’s equation for the These would behave like optical quanElectric and Magnetic field that plays tum well and can guide light along the this role. The periodic potential of the line. semiconductor crystal leads to pho- Nanoscopic Lasers: Photonic crystals nic band gaps. Similarly it is the pe- with point defects leads to “micro caviriodicity in the dielectric property of ties”, which generate a narrow so-called

six PCBs are fabricated per week. This number increases drastically during the EDP/EDL or during submission (Continued from Page 7) time mostly around Oct/Nov and Mar/Apr. Since renovation, the numThe entire operation takes around 8 ber of students availing these services hrs for pressing, and 6 hrs for cooling. is steadily increasing. Earlier, there This machine is controlled by a micro- was provision for making only single processor based lamination press. The sided PCBs but post-renovation, manMultipress II combined with ProtoMat ufacturing of multi-layered PCBs has and Minicontac II (for PTH) provide commenced which is one of the maa complete in house PCB prototyping jor reasons in the increase of the lab’s facility. utilization. The reason for the lack of awareness about the available facilities What is the level is perhaps the fact that the lab is not of usage of the associated directly with any course. facilities in the lab? Is the quality of PCBs made compaOn an average rable to the ones that are made in the

market? With the addition of the rapid prototyping technique, the quality is very much similar to PCBs manufactured outside. Is the manual chemical etching process still popular? The manual process involves printing the circuit, UV photo-printing, scrubbing, etching and drilling. On account of this being a manual process, reliability and accuracy are not very high for complex circuits. But nevertheless, it is employed for simpler circuits where the manual drilling of holes and shaping of tracks is manageable. Both the manual and automatic processes on an average take one day to manufacture a

defect mode. They can be used to make nano Lasers and LEDs that would emit light in a very narrow-bandwidth, together with highly selective optical filters. These tiny lasers acting as the modulating source, the channel waveguides acting as optical interconnects and the photonic crystal fiber can be integrated together to form an efficient optical communication system. Another application of these crystals in the field of optical communication networking is in making all-optical switches which does the routing and the header processing in optical domain, thus avoiding the need for optical-to-electrical-to-optical conversion at the router and switching junctions. Optical Transistors: A phenomenon called Kerr nonlinearity can be exploited in the photonic crystals to exhibit bistability. This has been shown experimentally and may lead to the birth of optical transistors, which would bring the next big revolution since the invention of the BJT. The next step then obviously, learning from history, would be the photonic Integrated Circuits. The ultimate aim would be to replace all electrons with photons and all semiconductors with photonic crystals. The vision is to have, one day, a computer which has a processor made of photonic crystal - a generation of computers, computing at speed in hundreds of terahertz, millions of times faster than the present generation computers. Much research has been done in this field over the last decade. The topic still remains a hot area of academic and industrial research. Interested readers may look at http://www.pgblink.com for more details. Even in IIT Bombay active research is being pursued in this field in the Dept. of Electrical Engineering, under Prof. R.K.Shevgaonkar and in the Dept. of Physics under Prof. R. Vijaya and Prof. B.P. Singh. Adnan Raja is 3rd Year B.Tech. student. He can be contacted at adnan@ee.iitb. ac.in. The author would like to thank Uday Khankhoje (4th Year B.Tech) for his useful inputs and feedback. PCB. The type of technique to be used for making the PCB can be specified while filling out the form. What are the major problems being faced in the present scenario? The only major problem is the scarcity of support staff. There used to be 5 employees earlier but after retirements, just two full time workers are left now. They have to handle both the manual process and the prototyping process, which becomes arduous and hard to deal with during the EDP/EDL period, taking into account the number of applications coming in during this period. Otherwise, from the infrastructure point-of-view, this lab is very wellequipped for its targeted objectives.

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Spectrum

ome every summer and students, especially sophomores, are busy pondering as to how to spend their vacation time productively and hunting for much soughtafter “projects” to be pursued during the holidays. Also, in recent years, the advent of the UROP has provided UG students with an excellent opportunity to explore their aptitude in research. A few words about UROP ﬁrst: UROPs are aimed to provide UG students who have good academic performance, an opportunity to get research experience by involving them in the ongoing research projects. The UROPs are categorized into sublevels: UROP01, 02 and 03. Both B.Tech. and DD students are eligible to pursue UROP01 which has no credits. The second and third levels, UROP02 and 03, for which only B.Tech. students are eligible, can be done in place of the ﬁnal year degree project. To ease the process for the interested students, Vivek Mishra of Background Hum talked to professors in the department and compiled a list of projects available for the students. Prof. V.M. Gadre gave details of the projects under his supervision. Currently, his research focus is on Fractional Fourier Transforms. Quadratic chirp characterization with Fractional Fourier Transforms was done by Uday Khankhoje under UROP01. Further, Harshad Kasture and Supreet Joshi

Check ’em Out !

broadly worked on a method of Fractional Fourier domain moments for characterizing linear and quadratic chirps. Arijit Sarkar and Jayakrishnan Unnikrishnan, worked on the use of wavelets in neural networks for time series analysis. Currently, two second year students, Prateek Gupta and Praneeth, are studying the detection and characterization of properties of Fractional Fourier Transform together with other transforms like Short Time Fourier Transform.

Switching to microelectronics, Prof. Souvik Mahaptra is working on Negative Bias Temperature Instability (NBTI) degradation in MOSFETs. Mohit Gupta, a sophomore, is studying the effects of the addition of various elements like boron, hydrogen, deuterium, nitrogen, fluorine etc. Studying this degradation is important because it can result in delays and unexpected device failure. Developing a model for this degradation is indeed a challenging job. Flash memories are another area of interest for Prof. Mahapatra. CMOS used in flash memories can change the fate of the presently used hard disks. Who knows 5-10 years down the line we might have easy to read, write and

erase portable flash memories instead of hard disks. Moving onto Controls and Computing, there is a lot of interesting stuff going on here as well. Prof. Preeti Rao & Prof. Sumantra Dutta Roy have floated a topic titled “Robust Music Information Retrieval Modeling, Search and Performance Evaluation”. A brief description of the project as given by Prof. Sumantra follows: “Current search methods and search engines are primarily text-based. Our plan is to look at the concept of Query-byHumming, wherein the user hums a song phrase, and the system retrieves the closest match. Apart from the basic signal processing, there is a good deal of system modeling involved to initiate a search based on part of a phrase in the song which itself may have errors, evolving efficient schemes for representation of songs in the database and developing efficient retrieval strategies. The coding for the algorithm development will be in C so as to link it with the current code base.” The prerequisites for the project are a good knowledge of coding. An interest in music will be appreciated.

AWARDS

Prof S Chaudhuri has been awarded Shanti Swarup Bhatnagar award in Engineering Sciences for the year 2004 for his seminal work in the area of computer vision. Prof V Ramagopal Rao has been selected for the prestigious Swarnajayanti fellowships awarded for the year 2004. Prof S Mahapatra has been selected for the prestigious INAE Young Engineer Award in recognition of his outstanding contributions in teaching, innovative development and engineering research in Electrical Engg. Prof U B Desai has been elected as a Fellow of the Indian National Science Academy for the year 2004. Prof T S Rathore received the award the IETE Prof SVC Aiya Memorial Award (2004) in recognition of his distinguished contribution in electronics and telecommunication research. IRCC Award: Dr P K Patwardhan Technology Development Award 2004 for innovative R&D was given to Prof A Karandikar for “Multiprotocol Label Switching Router” (MPLS)

�� Shriram

ACROSS

1. Dancers’ rut transforms into electrical signals 4. Sinusoidally twisted ﬁgure 7. Crazy remix 10. Warm voices sing at high frequencies 11. A stoic roll or rise and fall? 12. Something ten French girls are crazy about 13. If and buts reversed matches loads 14. A comets’ apron improves transients & PF!! 17. “Math! Christ, that makes me see circles!!” 18. Transport vehicle converter 20. Chuck out the high court for a change 21. Networks can inspire you to relate legends shortly 22. Can any quisling drinking tea decide about stability? 24. Impair elf who increases strength? 27. Waves could not have felt better!! 28. Crazily, a blocker two-up can see no more!!

t the same time as I decided to do my exchange year in Bombay, my flat mate decided to study one year in Tenerifa – a Spanish island which is a famous tourist destination with sun, sand and sea. We imagined that he would be surfing while I would be studying and learning mathematical formulae by heart. Well, the prospect of lying on the beach was tempting for me too, but I was too much interested in India, so I chose to spend my exchange year in Bombay. When I reached Bombay, the place was different from what I’d imagined. In some ways, perhaps unconsciously, I expected to meet a lot of boring people in not very colorful shirts working all day. Atleast I expected something in that direction. Instead, I got to know the Indians as very festive, open, tolerant, self-conscious, interesting and free people.

for me, where you can trust everyone. Especially for me, as an exchange student, this was very important. On the other hand, it was diﬃcult for me to get some distance from studies, as life is always happening very close to classrooms and labs.

ning before an exam, and before that I’d watch a movie or read a book to relax. I used to prepare for my exams during the semester. Unfortunately I never managed to do so in IIT, probably because of the inﬂuence of the other students. Everybody was joking about me because I used to go to bed The way of studying is also a bit dif- around PM :-) I never understood how ferent. Compared to IIT students, EPFL IIT students can watch so many mov-

students have much more responsibility. No one controls if people do their homework or if they go to classes. If someone doesn’t take his responsibility, he will fail the exams and repeat one year, or sometimes it is even impossible to continue studies in EPFL.

A big diﬀerence between EPFL and During my initial years in EPFL, I IIT is life on the campus. EPFL is a used to go to bed at 10 PM in the evecampus for studies only, atleast until now. There are no hostels on the campus itself and most of the students live in one of the surrounding cities or villages. Some have to take the train or car to get to EPFL. There is no night-life on the campus. In IIT, there are a lot of possibilities to enjoy the free time with friends. Activities like PAF and Mood Indigo (which I missed unfortunately) were a nice change from daily study life. I think life on campus creates an atmosphere that is also helpful for studies and research. The whole IIT community was like a huge family

loonEEy Toons

29. Crossbones or a gate??

DOWN

2. A tinted cam allows easy passage 3. Of this gaunt mathematician who was initially persecuted 5. Broken glasses mixed with alcohol provide a broad range 6. Noise when they strip pleasingly 8. Dire Celtic omens portend polarization 9. Excite a novice’s right to seize power 14. Endless communist at a headless station likes DC motor operation 15. Noticed in a gifts’ mall sign albeit as an approximation 16. Your humour splits frequency at the roots 19. Madly halt CPU to lose gate control 23. Fish sacrifices tail fin in exchange for miraculous simulation powers 25. A lab is turned weirdly upside down in France due to mismatches 26. Mechanical control mixed up in cricket parlance I met my flat mate again after my exchange year. He has learnt how to surf, and he’s missing it. I’m surely not missing learning the formulas by heart, but I’m surely missing my friends at IIT. Studies would have been easier if I had done all of them in Switzerland. Perhaps, I would have learnt more. But I wouldn’t have had the wonderful experience, the chance to see India with other eyes than the one of a tourist, to get to know many nice people, and to know “another way of doing it“.

I take advantage of the opportunity to thank all the people who helped to make my exchange year an unforgettaies during the semester, study the night ble one. I miss the swimming, playing before the exams and still get good re- water polo, going for treats, chatting, sults. There are some brilliant people studying, eating etc. with you. Thank in IIT. Only in the second semester, I you for the wonderful time. managed to get a grade I am proud of. Unfortunately, teamwork never really worked in my groups in the same way Tobias Thunherr was an exchange as it usually does in Switzerland. There student in our department from EPFL, were always one or two people who Lausanne, Switzerland during the last did the whole work and others who, at academic year 2003-04. most, supported them mentally.

by Suddu