A mathematical analysis of cellular interference on the performance of S-band military radar systems

In the United States, the 3500-3650 MHz band is a potential candidate for spectrum sharing between military radars and commercial cellular systems. This paper presents a framework for the analysis of radar performance under cellular interference. The impact on the performance of radar due to cellular interference is studied by deriving bounds on the probability of detection and probability of miss detection. For this purpose, we first derive the distribution of aggregate cellular interference, in a correlated shadow fading environment, at the radar receiver. We prove that the sum of interference signals from a cellular system has a log-normal distribution with probability 1. We then derive a lower bound on the probability of miss target where we consider our target to be a ship and target returns are modeled by a log-normal distribution. Along with the analytical results we also provide the corresponding simulation results showing degradation in radar performance due to interference from cellular systems.