A Dynamic Transmission Strategy for ISAC in Large Networks

A large network employing integrated sensing and communication (ISAC) where a single transmit signal by the base station serves both the radar and communication modes is studied. The radar-mode uses bistatic detection at a passive radar. Radar-mode performance, in general, is significantly more vulnerable than the communication-mode due to the double path loss in the signal component while interferers have direct links. To combat this, we propose a novel dynamic transmission strategy (DTS) where the quantity of radar-mode detection is traded for quality. We analyze the performance both the radar and communication modes with and without DTS and benchmark it with a traditional radar-only network. Our results highlight that with DTS we are able to significantly improve quality of radar detection at the cost of quantity. Further, DTS causes some performance deterioration to the communication-mode due to increased interference; however, the radar-mode gains attained are much higher. We show that dense deployment of low-cost passive radars offers superior detection for farther off targets, particularly compared to a radar-only network. With DTS, ISAC can further improve radar gains from its traditional counterpart.