Design of GMTI combining networks

Multichannel radar systems are of choice for ground moving target indication (GMTI) since they allow for a joint space-time processing of the received data that enables an efficient suppression of ground clutter returns. The design of the receiving sensor group is driven by the performance specifications of the intended GMTI modus, which usually requires the sensor array to consist of a few hundred up to a few thousand elements. Though desirable, a full digital processing of all receiving channels is practically not feasible due to both hardware constraints and computational load. The formation of sub-arrays using a proper combining network before A/D conversion reduces the number of processing channels while maintaining the advantages of the full array. In this paper the impact of the combining network design on the GMTI performance of a simulated airborne multichannel radar system is investigated.