Abstract: In this paper, we investigate the effect of friendly
jamming power allocation strategies on the achievable average
secrecy rate over a bank of parallel fading wiretap channels.
We investigate the achievable average secrecy rate in parallel
fading wiretap channels subject to Rayleigh and Rician fading.
The achievable average secrecy rate, due to the presence of a
line-of-sight component in the jammer channel is also evaluated.
Moreover, we study the detrimental effect of correlation across the
parallel sub-channels, and evaluate the corresponding decrease in the
achievable average secrecy rate for the various fading configurations.
We also investigate the tradeoff between the transmission power
and the jamming power for a fixed total power budget. Our
results, which are applicable to current orthogonal frequency division
multiplexing (OFDM) communications systems, shed further light on
the achievable average secrecy rates over a bank of parallel fading
channels in the presence of friendly jammers.
Abstract: In this paper, a Gaussian multiple input multiple output multiple eavesdropper (MIMOME) channel is considered where a transmitter communicates to a receiver in the presence of an eavesdropper. We present a technique for determining the secrecy capacity of the multiple input multiple output (MIMO) channel under Gaussian noise. We transform the degraded MIMOME channel into multiple single input multiple output (SIMO) Gaussian wire-tap channels and then use scalar approach to convert it into two equivalent multiple input single output (MISO) channels. The secrecy capacity model is then developed for the condition where the channel state information (CSI) for main channel only is known to the transmitter. The results show that the secret communication is possible when the eavesdropper channel noise is greater than a cutoff noise level. The outage probability is also analyzed of secrecy capacity is also analyzed. The effect of fading and outage probability is also analyzed.