Joint Radar and Communication System Optimization for Spectrum Sharing

Common approaches for radar and communication system spectrum sharing consider protection zones with power allocation for in-band operation, dynamic spectrum access (DSA) with spectrum sensing for in-band operation, and sense-and-avoid, frequency-agile approaches for out-of-band operation. In this paper we introduce a cooperative spectrum sharing model that combines multiple aspects of the previously mentioned approaches for in-band and out-of-band coexistence. This model jointly optimizes multiple radar and communication system parameters for improved frequency agility and performance while mitigating mutual interference between secondary radio-frequency (RF) users. Spectrum sensing is implemented to form a power spectral estimate of the electromagnetic environment (EME) to identify the secondary users. Multi-objective optimization then adjusts the output power, center frequency, and bandwidth parameters of the radar and communication system to maximize range resolution, radar signal to interference plus noise ratio (SINR), and channel capacity. Simulations are used to evaluate the model for different RF spectra. The results indicate that spectrum sharing is achieved for all systems.