Multi-Bit & Sequential Decentralized Detection of a Noncooperative Moving Target through a Generalized Rao Test

Abstract

We consider decentralized detection (DD) of an uncooperative moving target via wireless sensor networks (WSNs), measured in zero-mean unimodal noise. To address energy and bandwidth limitations, the sensors use multi-level quantizers. The encoded bits are then reported to a fusion center (FC) via binary symmetric channels. Herein, we propose a generalized Rao (G-Rao) test as a simpler alternative to the generalized likelihood ratio test (GLRT). Then, at the FC, a truncated one-sided sequential (TOS) test rule is considered in addition to the fixed-sample-size (FSS) manner. Further, the asymptotic performance of a trajectory-clairvoyant (multi-bit) Rao test is leveraged to develop an offline and per-sensor quantizer design. Detection gain measures are also introduced to assess resolution improvements. Simulations show the appeal of G-Rao test with respect to the GLRT, and the gain in detection by using multiple bits for quantization, as well as the advantage of the sequential detection approach.