ECE Seminar with Professor Chandra R. Murthy
- 3:00 pm on Tuesday, December 11, 2012
- Photonics Center, 8 Saint Mary’s St., Room 339
Distributed Co-Phasing for Data Fusion in Wireless Sensor Networks With Professor Chandra R. Murthy Department of Electrical Communication Engineering Indian Institute of Science Faculty Host: Venkatesh Saligrama Refreshments will be served outside Room 339 at 2:45 p.m. Abstract: In this work, we study the design and analysis of pilot-assisted Distributed Co-Phasing (DCP) schemes for data fusion in a wireless sensor network. First, we show via a mutual information analysis that higher order constellations significantly improve the throughput performance of DCP in comparison with binary constellations considered in earlier work. However, using a higher order constellation in the DCP setting requires estimation of the composite channel at the FC. To this end, we propose two blind algorithms for channel estimation at the FC: (i) a power method, and (ii) a modified K-means algorithm that is computationally efficient and converges significantly faster than the conventional K-means algorithm. We derive expressions for the probability of error and compare the performance of the two channel estimation algorithms both analytically and through simulations. The blind K-means algorithm achieves a probability of error comparable to that achievable with a perfect channel estimate at the FC, even with no pilot symbols being transmitted from the sensor nodes. We also investigate the problem of signal corruption due to imperfect DCP and design signal constellations that minimize signal corruption. We validate our analysis using Monte Carlo simulations. This is joint work with A. Manesh and Ramesh Annavajjala. About the Speaker: Chandra R. Murthy is an Assistant Professor in the Department of Electrical Communication Engineering at the Indian Institute of Science, in Bangalore, India. His research interests are primarily in the areas of digital signal processing, information theory, estimation theory, and their applications in the optimization of MIMO, OFDM and CDMA wireless communication systems.