Passive millimeter wave imaging: 2D sparse array optimization for low cost system architecture

In order to reduce the cost of passive imaging systems, the use of the switch matrix instead of the standard multi-channel acquisition schema is considered as a good strategy. However, the design of a switching matrix for millimeter wave imaging applications is a complex task, in particular on a 2D array which it depends mainly on the array topology, channels number and the required performances. In this work, an optimization methodology is proposed, which, for any given aperture size, can yield the optimum sparse array configurations with a very low redundancy and an optimized switching process. The goal is to reduce the complexity and the cost of the system architecture while maintaining high performances. Numerical results confirm a great efficiency of the proposed method. A good trade-off among the cost, performances and system complexity is reported.