AnyoneAnywhereAnytime

Cochannel Interference

Let the signal of the user go Crush the interferer

Estimation Filtering Temporal Detection Estimation Beamforming Spatial Enumeration Localization

TimeSpaceFrequencyWave NumberPeriodWave Length Filtering in Time Filtering in Space

Signals are localized in space. Get the spatial samples using an Antenna Array

Array Processing Applications Sonar Radar Seismology Medical Imaging Radio Telescopes Satellites Echo-beam Sounder Audio Conferencing Noise Cancellation Hands-free Mobile Communications Cellular Communications

Multichannel DSP Processor

T2T6T1T3T4T5 + G Assign the delays, Ti, such that the desired wavefront is received at the output.

Delay between two consecutive sensors: T2T1 + G d D = d sin(G) / c d: inter-element spacing G: angle of arrival c: wave speed

...T1Tk...T3T2 + G Choose: Ti = -(i-1) D All signal components from sensors arrive at the adder with the same phase. Signal Amplified

...T1Tk...T3T2 + G DDDDD W1W2W3W4W5W6 +

W1W2W3W4W5W6 + G Choose Wi such that: beam in the direction of the desired signal null in the direction of interference

Desired Signal Interference Desired Signal Interference

Space Division Multiple Access SDMA

Benefits: Reduced interference Reduced fading effect Easier hand-over Larger cell size Smaller BER Lower transmission power Smaller handsets Longer battery life Larger Capacity

 Center for Communications Research - University of Bristol Center for Communications Research - University of Bristol  Center for Personkommunikation - Aalborg University Center for Personkommunikation - Aalborg University  Center for Wireless Telecommunications - Virginia Tech Center for Wireless Telecommunications - Virginia Tech  Cornell University Blind Equalization Research Group Cornell University Blind Equalization Research Group  Image Processing & Communications Lab - Queen's University, Ontario Image Processing & Communications Lab - Queen's University, Ontario  INFOPAD, University of California at Berkeley INFOPAD, University of California at Berkeley  Mobile Computing at University of Washington Mobile Computing at University of Washington  Mobile Computing Laboratory, Columbia University Mobile Computing Laboratory, Columbia University  Mobile Computing Research at Purdue University Mobile Computing Research at Purdue University Some Active Research Centers:

 Mobile and Portable Radio Research Group (MPRG), Virginia Tech. Mobile and Portable Radio Research Group (MPRG), Virginia Tech.  Radio Systems Group at the University of Auckland Radio Systems Group at the University of Auckland  Research Group for RF Communications - University of Kaiserlautern Research Group for RF Communications - University of Kaiserlautern  Royal Institute of Technology - Signal Processing Royal Institute of Technology - Signal Processing  Smart Antenna Research Group - Stanford University Smart Antenna Research Group - Stanford University  Systems and Control Group, Uppsala University Systems and Control Group, Uppsala University  Telecommunications and Information Systems Engineering - University of Texas at Austin Telecommunications and Information Systems Engineering - University of Texas at Austin  Telecommunications at Georgia Tech Telecommunications at Georgia Tech  Uppsala University, Signals and Systems Uppsala University, Signals and Systems  WINLAB, Rutgers University WINLAB, Rutgers University  Wireless Technology Group - McMaster University Wireless Technology Group - McMaster University