Abstract:
We present a multi-user multiple-input multipleoutput
(MIMO) cognitive radio system consisting of a secondary
receiver that deploys spatial multiplexing to decode signals from
multiple secondary transmitters, under the presence of primary
transmissions. The secondary receiver carries out minimum
mean-squared error detection to decode the secondary data
streams, while it performs spectrum sensing at the remaining
signal to capture the potential presence of primary activity.
Assuming Rayleigh fading as well as the realistic cases of channel
fading time variation and channel estimation errors, we present
novel closed-form expressions for important system measures,
namely, the detection and false-alarm probabilities as well as
the transmission power of the secondary nodes. The enclosed
numerical results verify the accuracy of the presented analysis.