A prototype in 65-nm CMOS achieves 12 bits of resolution, with a fast settling time of less than five carrier c... We present a high-efficiency transmitter based on asymmetric multilevel outphasing (AMO). The new device contains two concentric rings of electrodes, which can be selectively activated to produce measurements in different directions, eliminating the need to repeatedly attach and detach single electrodes. The digital outphasing transmitter uses oversampling BPDSM, which reduces the digital RF signal resolution (as discussed in Section II) and also differentiate the digital outphasing transmitter from the conventional outphasing transmitters. It involves the application of a low-intensity alternating current to a muscle group and the measurement of the consequent surfa... We present a new adaptive power amplifier (PA) linearization technique. With the probe, the astronauts could evaluate whether they strong enough to open the hatch door, or perform other tasks requiring strength. MIT News | Massachusetts Institute of Technology. Rutkove enlisted Dawson to package the EIM system into a handheld device that doctors or physical therapists could easily use in their clinics. He went to MIT first for his formal training, earning a bachelor’s degree (1996) and a master’s degree (1997) in EE, and did his master’s thesis research at Bell Laboratories in Murray Hill, NJ. To gather useful data, however, impedance must be measured in several different directions across a muscle, which can be time-consuming. Shortly after taking a faculty position at MIT, Joel Dawson '96, SM '97 got together with his former music teacher, Elena Ruehr, for coffee. Markus Buehler, Joel Dawson and Scott Sheffield have received 2009 Presidential Early Career Awards for Scientists and Engineers, the nation's highest honor for professionals at the outset of their independent scientific research careers.. Buehler, Dawson and Sheffield are among 100 researchers to receive the honor this year.

gtag('config', 'UA-54415817-1', { We leverage analog Cartesian feedback (CFB) to train a Cartesian look-up table, reducing DSP and power amplifier modeling requirements to a minimum and eliminating model convergence as a design issue. The SoC corresponds to one EEG channel, and, depending on the patient, up to 18 channels may be worn to detect seizures as part of a chronic treatment system. Joel L. Dawson joined MIT as an Assistant Professor in the Department of Electrical Engineering and Computer Science (EECS) in September of 2004. and MEng degrees in Electrical Engineering from MIT in 1996 and 1997, respectively. Currently, muscle function is tested with electromyography, which requires a needle to be placed in the patient's muscle as the patient contracts it — a painful procedure. Ruehr, an MIT lecturer in music and theater arts, mentioned that her husband, a neurologist at Beth Israel, was looking for an engineer to help him with a device to measure muscle loss in patients with Lou Gehrig's Disease and other muscular ailments.

and MEng degrees in Electrical Engineering from MIT in 1996 and 1997, respectively. Cambridge, Massachusetts He received his S.B. The proposed technique combines the strength of the CFB, which is chiefly relaxed PA modeling requirements, with the increased speed of digital predistortion (DPD).... A 1.95-GHz asymmetric multilevel outphasing (AMO) transmitter with class-E GaN power amplifiers (PAs) and discrete supply modulators is presented.

In 2003 he co-founded Aspendos Communications, a fabless semiconductor company, before joining the MIT EECS faculty in 2004. "If you're going to use electrodes, you stick them on, do your measurement and then re-apply them in a different direction and do the measurement again," says Dawson. The IC, fabricated in a 0.18 μm CMOS process, consists of a switched-capacitor DC-DC converter, a 4 nW bandgap voltage reference, a high-efficiency rec... We present a high-efficiency transmitter architecture based on asymmetric multilevel outphasing (AMO), but with a new method of generating discrete amplitude levels from the constituent amplifiers. "In principle, we could have stopped there.

Shortly after taking a faculty position at MIT, Joel Dawson '96, SM '97 got together with his former music teacher, Elena Ruehr, for coffee. The first generation of their device produced accurate measurements, but with its spiky electrodes protruding, was not patient-friendly.

“Whatever the outcome, I very much hope that in our interactions with one another, we can hold ourselves to our usual high standards of kindness, decency, compassion, inclusion and mutual respect,” writes President L. Rafael Reif.

He left MIT to found Eta Devices (as CTO) based on some of his MIT research - a new architecture enabling major improvement in the achievable efficiencies of cell phone and base station transmitters.

Once perfected, the device could be used not only to study ALS but also to help evaluate muscle health in patients with other disorders, such as muscular dystrophy. In a LUT based digital predistorter, each LUT entry is specified at only one single point of the inverse PA characteristics.

Dawson and his colleagues describe the latest generation of the EIM probe in a paper they have submitted to the Annals of Biomedical Engineering. Rutkove and Dawson's probe assesses muscle loss using electric impedance myography (EIM), which measures muscle's resistance to an electrical current by passing a small, non-painful amount of current though the muscle using two electrodes. 1�¾G5;ùÊ Ò@fTœth‡ø�éø¶/*¯XzëbY¸Ú„�wûú£:`hqÄ€]ÅçÈÄıíT>ÔµÇv–Gh0¼pŸ…Vsnï�9Œ-"¥èe‘ĞYÓP�{émx ì Ÿ¶jĞtç¤2˜¦ß„9ø²=7‘uœ5ø –9­3«„6ko†Èf�h¡-

Rutkove and Dawson's probe assesses muscle loss using electric impedance myography (EIM), which measures muscle's resistance to an electrical current by passing a small, non-painful amount of current though the muscle using two electrodes. "Once somebody is diagnosed, we don't have a great way of tracking the progression of the disease," says Rutkove.

We were getting the data we wanted, but a physical therapist is not going to use something like this. This letter presents a 2.14 GHz, four-way power combining and outphasing system for high-power amplifiers such as those in radio basestations (RBS). "If you're going to use electrodes, you stick them on, do your measurement and then re-apply them in a different direction and do the measurement again," says Dawson. noise folding problems of subsampling, obtaining a final SNDR of

Massachusetts Institute of Technology77 Massachusetts Avenue, Cambridge, MA, USA. MIT engineer Joel Dawson and colleagues built a handheld probe that could help doctors monitor muscle atrophy in patients with Lou Gehrig's Disease and similar ailments. PhD and MSc degrees in Electrical Engineering (University of California, Berkeley), BSc in Electrical Engineering and a BA in Sociology (Purdue University). With help from MIT postdoctoral associate Hong Ma, the team made the probe smaller and easier to use, and built an electrode array with a flat surface instead of spikes, making it more comfortable for patients. For his work at MIT, Dr. Dawson received the NSF Career Award in 2008. Electrical Engineering and Computer Science He received the S.B. He received his S.B. Monitoring muscle

This is due to the fact that, the bandwidth of the phase of a two-dimensional signal is much higher than the original signal [7]. IEEE MTT-S International Microwave Symposium (5), IEEE Transactions on Microwave Theory and Techniques (4), Circuits and Systems II: Express Briefs, IEEE Transactions on (2). Making the probe more user friendly was a process Dawson compared to Apple's design of the iPod and iPhone.

MIT Electrical Engineering & Computer Science | Room 38-401 | 77 Massachusetts Avenue | Cambridge, MA 02139 The first generation of their device produced accurate measurements, but with its spiky electrodes protruding, was not patient-friendly.

"If you're interested in more than two directions, you can see it's a long procedure." With the probe, the astronauts could evaluate whether they strong enough to open the hatch door, or perform other tasks requiring strength. In 2003 he co-founded Aspendos Communications, a startup company based in San Jose, CA.

During the six-month trip, astronauts would lose muscle mass due to the lack of gravity, but there's no easy way to measure just how much their strength would be affected. In 2009, he was selected for the Presidential Early Career Award for Scientist and Engineers (PECASE). The energy recovery system can simulate the behavior and performance of a resistive termination, while recovering at least some of the energy that would otherwise have been dissipated within the termination. They presented the first generation probe at the IEEE International Engineering in Medicine and Biology Conference last year. "MP3 players had been around for a long time, but they didn't really take off until they were easy to use," he says. Joel L. Dawson joined MIT as an Assistant Professor in the Department of Electrical Engineering and Computer Science (EECS) in September of 2004. The disease attacks the motor neurons that control voluntary muscle movement, leading to muscle weakness and atrophy. This paper presents a low-power, low-complexity adaptive digital predistortion system based on a quadrature ΔΣ modulator for linearizing WLAN PAs. }); A discrete-component power combiner is designed and characterized, and combined with i... A tunable and highly digital RF frontend for multi-band TDD radios is integrated in 45nm SOI CMOS. 0âäüJKÀ À�:š|/õW_MÓápøk˜ã‡í1æf1�1“Иãå�q¤Íƒæ'䉶[Y)Ğû¹e5L`�ºo;q:y¾Ûı;ÆjMWNzÌ�?�uœåyQ � —=�ÖåV¯øî&à‰nк'ÔéÉ%p»¹ÜÚ Joel Dawson's recitation notes for parts of an earlier version of 6.302 are available on open courseware, recitation notes, 2007's 6.302. It exploits oversampling and digital design to reduce system area and power, while making the system more robust to interferers. Our energy-efficient lookup table training... We describe a general offset-canceling architecture for analog multiplication using chopper stabilization. "If they can successfully develop a handheld probe that you simply place on a patient's skin, it could be a non-invasive and very speedy test to perform at the bedside, with no discomfort to the patient," he says. We were getting the data we wanted, but a physical therapist is not going to use something like this. The modulator achieves 12-bit resolution at a measured 20... A compact, low-power, digitally-assisted sensor interface for biomedical applications is presented. Executive director of the International Energy Agency is optimistic about how quickly the world may shift to cleaner energy and achieve international decarbonization goals. Once perfected, the device could be used not only to study ALS but also to help evaluate muscle health in patients with other disorders, such as muscular dystrophy.