Characterizing the Impacts of Rice Fading on a WiFi-based Passive Multistatic Radar Using Cramer-Rao Bound

In this paper, the performance of a WiFi-based passive multistatic radar is studied in a Rice fading (RF) environment, where the received signal from the target is composed of fixed amplitude or dominant scatterer (DS) component and weak isotropic scatterers (WIS) component. The likelihood expression of the received signal is derived and modified Cramer-Rao lower bound (MCRLB) expressions for 3D Euclidean components of target position and velocity are computed. It is shown that in presence of RF, the total modified Fisher information matrix (MFIM) is a linear combination of MFIM due to WIS and DS components. With the help of numerical examples, it is established that existence of DS component increases target radar cross section (RCS), which improves the detection and estimation accuracy. It is also shown that by exploiting DS, the performance of a waveform can be analyzed for generalized radar cross section model (GRCSM), which shows its characterization for various radar applications.