1. EE608 Adaptive Signal Processing Course Project Adaptive Beamforming For Mobile Communication
Group: 1
Chirag Pujara ( )
Prakshep Mehta ( )
V B Bhedaru ( )

2. 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

3. 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

4. Principle of Beamforming
Beam can be formed at desired angle by controlling the phase between elements.
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EE608 Adaptive Signal Processing

5. 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

6. 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

7. 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

8. EE608 Adaptive Signal Processing
Simulation Results
Convergence in NLMS ~50 symbol durations and LMS ~65 symbol durations
Assuming 64kbps channel it will require 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

9. 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

10. EE608 Adaptive Signal Processing
Queries
Thank You
11/10/2018
EE608 Adaptive Signal Processing