Achievable Secrecy Sum-Rate in a Fading MAC-WT with Power Control and without CSI of Eavesdropper

TL;DR

This paper investigates the achievable secrecy sum-rate in a fading MAC-WT with power control and cooperative jamming, demonstrating that jamming significantly enhances secrecy even without eavesdropper CSI.

Contribution

It introduces an optimal power control scheme and a practical ON/OFF power control method with cooperative jamming for secrecy enhancement without eavesdropper CSI.

Findings

Jamming improves secrecy sum-rate significantly.

High SNR performance with jamming exceeds that with full CSI.

ON/OFF power control is effective and computationally simple.

Abstract

We consider a two user fading Multiple Access Channel with a wire-tapper (MAC-WT) where the transmitter has the channel state information (CSI) to the intended receiver but not to the eavesdropper (eve). We provide an achievable secrecy sum-rate with optimal power control. We next provide a secrecy sum-rate with optimal power control and cooperative jamming (CJ). We then study an achievable secrecy sum rate by employing an ON/OFF power control scheme which is more easily computable. We also employ CJ over this power control scheme. Results show that CJ boosts the secrecy sum-rate significantly even if we do not know the CSI of the eve's channel. At high SNR, the secrecy sum-rate (with CJ) without CSI of the eve exceeds the secrecy sum-rate (without CJ) with full CSI of the eve.