Wireless Channel Capacity Fundamental Limit on Data Rates
Capacity: The set of simultaneously achievable rates {R1,…,Rn}
R3
R1
R2
R3
R2 R1
Impact of ISI on Capacity Impact of Multiple Antennas on Capacity
Broadcast Channels with ISI
ISI introduces memory into the channel
The optimal coding strategy decomposes the channel into parallel broadcast channels
Superposition coding is applied to each subchannel.
Power must be optimized across subchannels and between users in each subchannel.
Broadcast Channel Model
w1k xk
H1(w)
y1k h1i xk i w1k
i 1
m
w2k
H2(w)
y2 k h2i xk i w2 k
i 1
m
Both H1 and H2 are finite IR filters of length m. The w1k and w2k are correlated noise samples. For 1