EE608 Adaptive Signal Processing Course Project Adaptive Beamforming For Mobile Communication Group: 1 Chirag Pujara (03307901) Prakshep Mehta (03307909) V B Bhedaru (04307301)
EE608 Adaptive Signal Processing What is Smart Antenna…? Omni-directional Antennas – No Spectrum Reuse in the Same Cell Sectored Antennas – Spectrum Reuse possible Novel Concept Smart Antenna – Beam Steering 11/10/2018 EE608 Adaptive Signal Processing
Benefits of Smart Antenna More accurate directional targeting and additional improvements in efficiency Base station finds out the direction of the user using relative signal strengths at multiple antennas and then direct the Beam toward user. Beam steering will thus reduce the interference and increase the capacity of the cell. 11/10/2018 EE608 Adaptive Signal Processing
Principle of Beamforming Beam can be formed at desired angle by controlling the phase between elements. 11/10/2018 EE608 Adaptive Signal Processing
EE608 Adaptive Signal Processing Design parameters Uniform linear array 10 Isotropic radiators as array elements Spacing d = Beam width=10.16o Assumptions Angle of arrival is known User will remain steady during convergence ~ 50 symbol duration 11/10/2018 EE608 Adaptive Signal Processing
EE608 Adaptive Signal Processing Algorithm Sine wave of 1 Hz (2*pi rad/sec) for Training Y[n]=A * exp (j*w*n) Sampled at 10 Hz (2*pi/10 rad/sec) 5 times the Nyquist sampling frequency Generating data at antenna elements- spatial filtering by multiplying sampled signal with steering vector x[n]=y[n]*s[n] 11/10/2018 EE608 Adaptive Signal Processing
EE608 Adaptive Signal Processing Algorithm (Cont…) Φ=angle of arrival and can be known from DOA estimation LMS (µ = 0.01) / NLMS (a=0.5, b=0.0001) algorithm for adaptively calculating the weights 11/10/2018 EE608 Adaptive Signal Processing
EE608 Adaptive Signal Processing Simulation Results Convergence in NLMS ~50 symbol durations and LMS ~65 symbol durations Assuming 64kbps channel it will require 0.781 msec for convergence and user can move at max 42 mm in this time at the speed of 200 kmph 11/10/2018 EE608 Adaptive Signal Processing
EE608 Adaptive Signal Processing Future Work Algorithm for finding DOA can be implemented Existing algorithm can be modified to place nulls at specified locations -- Support Multiple Users Lateral movement of the host body can be compensated adaptively using additional LMS/NLMS algorithm 11/10/2018 EE608 Adaptive Signal Processing
EE608 Adaptive Signal Processing Queries Thank You 11/10/2018 EE608 Adaptive Signal Processing