November 2016

Sachin Katti and Pengyu Zhang, a postdoctoral researcher in Katti's lab, announced "HitchHike" this week at the ACM SenSys Conference. HitchHike is a tiny, ultra-low-energy wireless radio.

"HitchHike is the first self-sufficient WiFi system that enables data transmission using just micro-watts of energy – almost zero," Zhang said. "Better yet, it can be used as-is with existing WiFi without modification or additional equipment. You can use it right now with a cell phone and your off-the-shelf WiFi router."

HitchHike is so low-power that a small battery could drive it for a decade or more, the researchers say. It even has the potential to harvest energy from existing radio waves and use that electromagnetic energy, plucked from its surroundings, to power itself, perhaps indefinitely.

"HitchHike could lead to widespread adoption in the Internet of Things," Katti said. "Sensors could be deployed anywhere we can put a coin battery that has existing WiFi. The technology could potentially even operate without batteries. That would be a big development in this field."

The researchers say HitchHike could be available to be incorporated into wireless devices in the next three to five years.

The Hitchhike prototype is a processor and radio in one. It measures about the size of a postage stamp, but the engineers believe that they can make it smaller – perhaps even smaller than a grain of rice for use in implanted bio-devices like a wireless heart rate sensor (see video).

"HitchHike opens the doors for widespread deployment of low-power WiFi communication using widely available WiFi infrastructure and, for the first time, truly empower the Internet of Things," Zhang said.



Excerpted from Stanford Engineering News. Original article by Andrew Myers


Jon Fan's research on nanoscale optical devices
November 2016

A field of materials science known as metamaterials has recently captured the imagination of engineers hoping to create nanoscale optical devices. Jonathan Fan, an assistant professor of electrical engineering and director of the ExFab at the Stanford Nanofabrication Facility, is leading the way. He recently won the prestigious 2016 Packard Fellowship in Science and Engineering, which funds the most promising early-career professors in fields ranging from physics and chemistry to engineering. Fan is just the fourth Stanford electrical engineer to win the fellowship since 1988, and the financial support that comes with it will enable him to carry on work that is so innovative that it can otherwise prove difficult to fund through traditional means. We talked to Fan about his visions in metamaterial engineering and about his interdisciplinary collaborations with fellow Stanford professors Allison Okamura and Sean Follmer in projects such as integrating new types of electromagnetic systems with robots.

What are metamaterials?

At its most basic level, we are bringing the idea of an antenna down to the nanoscale. Back in the day before cable and satellite, TVs had metal antennas. If your picture wasn't very good, you would get up and physically reconfigure the antenna geometry to change its performance. Those antennas were designed for radio waves that were centimeters to meters in length. We are working to create nanoscale antennas that would be able to respond to visible light with wavelengths of 400 to 700 nanometers, or infrared light, where wavelengths are on the order of a micron. By configuring the geometry of these antennas individually and in collections, we can engineer systems that can interact with and manipulate light in entirely new ways.

These tiny antennas are many orders of magnitude smaller than a TV antenna. Fortunately, the development of the modern electronic integrated circuit platform over the last half-century has produced mature technological processes that can help us define nanoscale features. We use those same patterning technologies to make these nanoscale antennas. That's the very basic overview.

What is the derivation of the term "meta" in the name metamaterials?

When you think of a conventional lens, you think of glass – the material, right? The glass in your camera or your eyeglasses bends light in very predictable ways based on the intrinsic material response of glass. A lens made of a metamaterial will respond to light in ways that are no longer solely based on the properties of the material itself, but largely on the design and layout of these optical antennas. So the concept of "meta" comes from our ability to engineer artificial materials, consisting of a composite of nanoscale structures, which can respond to light in entirely new ways. It's kind of neat to see an example in the case of a metal like gold. We usually think of gold as a bulk material that is reflective, yellowish and shiny. Even when you go down to the nanoscale, gold is still gold. But by specifying the geometry of nanoscale gold, we can change the color of gold from yellow to green or red, and it can support many other types of optical properties that we don't associate with bulk gold. Those are properties engineers can use to make new devices.

What do metamaterials allow us to do that we couldn't before?

Metamaterials are promising for a couple reasons. First, they enable the extreme miniaturization of existing optical devices. For example, we can take an eyeglass lens and we can make it 100 times thinner than a strand of hair. This allows us to translate traditionally bulky optical systems to extremely small form factors. Second, they can be customized to support novel properties that currently are not accessible with existing optical hardware, leading to entirely new optical systems.

What's an example of a potential metamaterial device?

A major opportunity today arises from the fact that high-resolution cameras have miniaturized to sizes that can fit onto cellphones, making them accessible to audiences a million times larger than before. Part of my larger research question is: Is there something more we can do with imaging systems with form factors of a cellphone camera? There is so much information in the incoming light field that is not currently captured by a cellphone camera, but that could be captured with imaging systems that include metamaterials. Access to this additional information could change how we use the images we take. For example, if you have a skin condition, a great deal more optical information of the skin could be extracted from a simple cellphone image and used to better assess your condition.

What excites you about metamaterials?

Metamaterials lead us to a completely different set of questions – metaquestions, if you will. For instance, are these nanoantennas even the best way to go about doing what we want to do? At this point in time, even that's not clear. In addition, you get to the big questions of applications for these materials and devices. It's just wide open. That's why this is exciting to me.

Any early impressions to share as a new faculty member?

Stanford is a really special place. The people are top-notch and the environment is highly collaborative, not siloed. As an example, I have recently expanded into robotics, where I have been looking to apply concepts in radio frequency waves to create smarter soft robotic systems. In this effort, I've started a collaboration with Allison Okamura and Sean Follmer, who are mechanical engineers. It's been fantastic so far, and I've been learning so much. People here are very open-minded and are inspired to do exciting interdisciplinary research to identify and solve big problems. I'm thrilled to be a part of that.

By Andrew Myers
Source: Stanford School of Engineering News



Related News:

Fan awarded the Presidential Early Career Awards for Scientists and Engineers, January 2017

Jonathan Fan awarded 2016 Packard Fellowship for Science and Engineering, October 2016

Jonathan's EE Spotlight

November 2016

Professor Andrea Goldsmith and post-doc fellow Nariman Farsad are currently looking into how chemical communication could advance nanotechnology.

Goldsmith and Farsad's research aims to create a system that uses chemicals to transmit messages. Instead of zeros and ones, their system uses an acid-base combination. The complications of this type of system are largely due to the fact that it's completely new. Goldsmith has spent her entire career working in wireless communication. Chemical messaging offers a new twist on familiar problems.

One potential of chemical-based data exchange is that it could be self-powered, traveling throughout the body harmlessly – and undetectable by outside devices. "This is one of the most important potential applications for this type of project," Farsad said. "It could enable the emergence of these tiny devices that are working together, talking together and doing useful things."

While working to improve their current chemical texting system, Goldsmith and Farsad are also collaborating with two bioengineering groups at Stanford to make human body-friendly chemical messaging a reality.


Excerpted from Stanford News. Full article.

November 2016

A team led by Jim Harris and Thomas Jaramillo, an associate professor of chemical engineering and of photon science, has made a significant improvement to the efficiency of solar energy. In work published in Nature Communications, they were able to capture and store 30 percent of the energy captured from sunlight into stored hydrogen, beating the prior record of 24.4 percent.

Solar energy has the potential to provide abundant power, but only if scientists solve two key issues: storing the energy for use at all hours, particularly at night, and making the technology more cost effective. The interdisciplinary team has made significant strides toward solving the storage issue, demonstrating the most efficient means yet of storing electricity captured from sunlight in the form of chemical bonds. If the team can find a way of lowering the cost of their technology, they say it would be a huge step toward making solar power a viable alternative to current, more polluting energy sources.

The basic science behind the team's approach is well understood: Use the electricity captured from sunlight to split water molecules into hydrogen and oxygen gas. That stored energy can be recovered later in different ways: by recombining the hydrogen and oxygen into water to release electricity again, or by burning the hydrogen gas in an internal combustion engine, similar to those running on petroleum products today.

"It took specialists in different fields to do what none of us could have done alone," Harris said. "That's one of the lessons of this result: There is no single fix. How everything links together is the key."


Jim Harris is the James and Elenor Chesebrough Professor in the School of Engineering, professor, by courtesy, of applied physics and of materials science and engineering, a member of Stanford Bio-X and of the Stanford Neurosciences Institute, and an affiliate of the Precourt Institute for Energy and the Stanford Woods Institute for the Environment. Jamarillo is also an affiliate of the Precourt Institute for Energy.


This article is adapted from the Stanford Report. Read full article

October 2016

Congratulations to David H. Lin (PhD '16), Eshan Singh (PhD candidate), and Professor Subhasish Mitra for receiving the 2015 IEEE International Test Conference (ITC) Best Paper Award.

To encourage excellence in its technical program, ITC presents awards to authors of outstanding papers presented at ITC and published in the proceedings. In determining award-winning papers, the ITC Awards Selection Committee considers the quality of the papers as published in the Proceedings and as presented at the conference technical sessions. The committee's decisions are based on responses by conference attendees as recorded on session rating cards and on the observations and recommendations of the ITC Program Committee.

Their paper, "A Structured Approach to Post-Silicon Validation and Debug using Symbolic Quick Error Detection", has been selected as the Best Paper for International Test Conference (ITC).

The Best Paper Award will be presented to Mitra and co-authors during the plenary session at ITC on November 15th.


Congratulations to all!

October 2016

Stephen P. Boyd has been named as a 2016 INFORMS Fellow. The Fellow Award is reserved for distinguished individuals who have demonstrated outstanding and exceptional accomplishments in operations research and the management sciences.

His citation reads, "For exceptional teaching and broad dissemination of convex optimization and outstanding research leading to innovative formulations and algorithms for problems across a wide array of disciplines."

Stephen has received many awards and honors for his research in control systems engineering and optimization. In 2016, he also received Stanford's highest teaching honor, the Walter J. Gores teaching award for his signature course, Convex Optimization. He is the author of many research articles and three books: Convex Optimization (with Lieven Vandenberghe, 2004), Linear Matrix Inequalities in System and Control Theory (with L. El Ghaoui, E. Feron, and V. Balakrishnan, 1994), and Linear Controller Design: Limits of Performance (with Craig Barratt, 1991). His group has produced many open source tools, including CVX (with Michael Grant), CVXPY (with Steven Diamond) and Convex.jl (with Madeleine Udell and others), widely used parser-solvers for convex optimization.

Stephen is the Samsung Professor of Engineering, and Professor of Electrical Engineering in the Information Systems Laboratory at Stanford University. He has courtesy appointments in the Department of Management Science and Engineering and the Department of Computer Science, and is member of the Institute for Computational and Mathematical Engineering. His current research focus is on convex optimization applications in control, signal processing, finance, and circuit design.


Please join us in congratulating Stephen for this well-deserved honor.



October 2016

Excerpted from Dean Drell's announcement:
President Emeritus John L. Hennessy has been appointed as the inaugural James F. Gibbons Professor in the School of Engineering. This chair was established with an endowed gift from James and Lynn Gibbons. The chair carries with it a preference for faculty who have demonstrated leadership and show leadership potential that will serve the ideals of Stanford University.

John joined Stanford's faculty in 1977 as an assistant professor of electrical engineering. From 1983 to 1993, he was director of the Computer Systems Laboratory. He served as chair of the computer science department from 1994 to 1996, and later that year was named dean of the School of Engineering. In 1999, he was named provost before serving as Stanford University president from 2000 to 2016.

A pioneer in computer architecture, John and a team of researchers developed the Reduced Instruction Set Computer (RISC), a technology that revolutionized the computer industry by increasing performance while reducing costs. During a sabbatical leave from Stanford in 1984, he co-founded MIPS Computer Systems (now MIPS Technologies), which designs microprocessors. John co-authored two widely used textbooks on computer architecture: Computer Organization and Design: The Hardware/Software Interface and Computer Architecture: A Quantitative Approach.

John received a bachelor's degree in electrical engineering from Villanova University in 1973 and a master's degree and PhD in computer science from the State University of New York, Stony Brook, in 1975 and 1977, respectively.

He has served on the boards of directors at Cisco Systems since 2002 and Google since 2004, and was on the Atheros board of directors from 1998 to 2010.

John is a recipient of many awards, including the Institute of Electrical and Electronics Engineers (IEEE) Medal of Honor, the Founders Award from the American Academy of Arts and Sciences, and the Seymour Cray Computer Engineering Award from the IEEE Computer Society. He is a member of the National Academy of Engineering and the National Academy of Sciences, and a fellow at the IEEE, the American Academy of Arts and Sciences, the Association for Computing Machinery, and the Computer History Museum.

John's far-reaching impact on engineering, his visionary leadership in transforming higher education, and his commitment to preserving and enhancing Stanford's excellence as one of the world's leading research and teaching institutions make him a quintessential leader and the ideal match for this endowed chair.


Please join us in congratulating John!

October 2016

Excerpted from Dean Drell's announcement:

Mendel Rosenblum has been appointed as the inaugural DRC Professor in the School of Engineering. This professorship was established with an endowed gift from David Cheriton. The chair carries with it a preference for faculty whose academic focus is in experimental computer systems.

Mendel has been a member of the Stanford faculty since 1991. He currently serves as the faculty director of the Stanford Experimental Data Center Laboratory and the Stanford Computer Forum. His research is focused on system software, distributed systems, and computer architecture. Mendel has published research in the areas of disk storage management, computer simulation techniques, scalable operating system structure, virtualization computer security, and mobility.

A co-founder of VMware Inc., Mendel helped design and build virtualization technology for commodity computing platforms. He is a recipient of the National Science Foundation's National Young Investigator Award, and the Alfred P. Sloan Foundation Research Fellowship. Additionally, he is the recipient of the Institute of Electrical and Electronics Engineers' Computer Entrepreneur Award and Reynold B. Johnson Information Storage Systems Award. Mendel is a fellow of the Association for Computing Machinery and a member of the National Academy of Engineering.

Mendel received a bachelor's degree in mathematics from the University of Virginia in 1984, and a master's degree and PhD in computer science from the University of California, Berkeley, in 1989 and 1992, respectively.


Please join us in congratulating Mendel!

October 2016

EE's Jonathan Fan has been named one of the nation's most innovative early-career scientists and engineers by the David and Lucile Packard Foundation. 

Jonathan's research aims to push the physical limits of miniaturized optical systems to new functional regimes, using a multi-disciplinary effort that combines materials science, nanotechnology, and computational design.

Beginning in 1988, the Packard Fellowship has awarded support to promising early-career professors from 50 universities in the fields of physics, chemistry, mathematics, biology, astronomy, computer science, earth science, ocean science, and all branches of engineering. The Packard Fellowships are among the nation's largest nongovernmental fellowships, designed to allow maximum flexibility in how the funding is used. 

Please join us in congratulating Jonathan for this very well-deserved recognition of his stellar work on electromagnetics, plasmonics, and flexible and stretchable electronics.


Read more about the 2016 Packard Fellowships

Fan Lab - Applied Nanophotonics Lab 

September 2016

For years, the net neutrality debate has been at an impasse: either the internet is open or preferences are allowed. But professors Nick McKeown and Sachin Katti, and EE PhD Yiannis Yiakoumis ­– say their new technology, called Network Cookies, makes it possible to have preferential delivery and an open internet. Network Cookies allow users to choose which home or mobile traffic should get favored delivery, while putting network operators and content providers on a level playing field in catering to such user-signaled preferences.

"So far, net neutrality has been promoted as the best possible defense for users," Katti said. "But treating all traffic the same isn't necessarily the best way to protect users. It often restricts their options and this is why so-called exceptions from neutrality often come up. We think the best way to ensure that ISPs and content providers don't make decisions that conflict with the interests of users is to let users decide how to configure their own traffic."

McKeown said Network Cookies implement user-directed preferences in ways that are consistent with the principles of net neutrality.

"First, they're simple to use and powerful," McKeown said. "They enable you to fast-lane or zero-rate traffic from any application or website you want, not just the few, very popular applications. This is particularly important for smaller content providers – and their users – who can't afford to establish relationships with ISPs. Second, they're practical to deploy. They don't overwhelm the user or bog down user devices and network operators and they function with a variety of protocols. Finally, they can be a very practical tool for regulators, as they can help them design simple and clear policies and then audit how well different parties adhere to them."


This article is adapted from Stanford Engineering News. Read full article.


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