Wireless local positioning system via DS-CDMA and beamforming: a perturbation analysis

In this paper, we analyze the perturbation effects on the performance of a novel wireless local position system (WLPS) with applications in homeland security, defense, vehicle collision avoidance, and multi-robot collaboration and coordination. This WLPS has two main components: (1) a dynamic base station (DBS), and (2) a transponder (TRX), mounted at the monitoring and target mobiles, respectively. The DBS detects TRX via unique ID codes assigned to them. This structure leads to a unique wireless structure. In this work, we assume direct-sequence code division multiple access (DS-CDMA) transmission in the uplink (i.e., from TRX to DBS), and antenna array with conventional beamforming (BF) mounted at the DBS. This structure leads to a high probability-of-detection (POD) performance and capacity (in terms of number of TRX) at the DBS receiver. We analyze the effect of perturbations, which lead to antenna weight vector error, reduce the POD performance and the capacity of the WLPS system. Simulation are performed specifically for applications of WLPS systems in vehicle collision avoidance.