Performance analysis of legitimate UAV surveillance system with suspicious relay and anti-surveillance technology

We propose a legal Unmanned Aerial Vehicle(UAV)surveillance system to perform passive surveillance or active jamming while in the presence of a suspicious relay or source,where a UAV works in half-duplex mode and the relay/source deploys artificial noise to prevent monitoring.Three schemes are considered for a Multiple-Input Multiple-Output(MIMO)UAV:surveilling followed by jamming;jamming followed by surveilling;and two-stage surveilling.For each scheme,a closed-form expression of surveilling non-outage probability is derived,and surveilling performance under different system configurations is analyzed.Monte Carlo(MC)simulation validates derivation correctness.

Cooperative Proactive Eavesdropping over Two-Hop Suspicious Communication Based on Reinforcement Learning

Legitimate surveillance has attracted more and more concern,and effective proactive intervention can eavesdrop the illegitimate information.In this paper,we propose legitimate eavesdropping over a two-hop suspicious communication link by two full-duplex legitimate monitors(LMs)based on multi-agent deep deterministic policy gradient(MADDPG)algorithm in two phases.In phase 1,the suspicious transmitter sends information to the suspicious assistant relay,and the assistant relay decodes and forwards the received message to the suspicious receiver in phase 2.Meanwhile,two LMs cooperatively emit jamming to suspicious relay and receiver during each phase.Particularly,each LM is considered to be an energy-limited device,and eavesdropping is a long-term process,so we adopt expected eavesdropping energy efficiency(EEE)over a period of time to evaluate eavesdropping performance.However,for two LMs,how to cooperatively make jamming power decision at each hop in a dynamic environment is a huge challenge.Therefore,MADDPG algorithm,as a multi-agent reinforcement learning approach with the advantage of dynamic decision-making,is utilized to solve the issue of jamming power decision for each LM.In the simulation,the results show that our proposed cooperative jamming scheme can obtain higher expected EEE.