A DVB-S-Based Multichannel Passive Radar System for Vehicle Detection

Vehicle detection systems play a significant role in intelligent transportation systems (ITSs). At present, vehicle detection is realized either by very costly inductive loops, by video cameras that require good weather conditions and high computing resources, or by recently developed magnetic sensors that only obtain limited detection accuracy in congested traffic conditions. To overcome these challenges, this paper develops a passive radar system that is robust to bad weather conditions, low cost and radio silent for vehicle detection. The device is installed at the side of the road under crowded traffic conditions. In the developed system, cross-correlation (CC) operation is applied to obtain suboptimal detection gain and computational complexity. To decrease the impact of interference that is independently and identically distributed (i.i.d.) across isolated frequency channels and that of the Doppler effect produced by a mobile vehicle, a multichannel joint detection scheme based on multichannel fusion (MCF) is proposed and implemented. Furthermore, to achieve high resolution, an illuminator of opportunity (IO) with wide bandwidth is selected, and the system is then designed to receive a digital video broadcast-satellite (DVB-S) signal with a bandwidth of 37.5 MHz over multiple channels simultaneously. Simulation results show that the proposed MCF achieves better performance than the single-channel-based CC, and the advantage can be enhanced by increasing the number of channels for joint detection. Field test results further verify the novelty of the MCF and the developed passive radar prototype.