Automatic Fractional Delay Inference for Coherent Cognitive Radio Receivers Using Space‐Time Adaptive Algorithms

ABSTRACT

Maintaining strict synchronization among receive channels, as well as ensuring persistent automatic calibration, represents a key challenge in coherent receiver architectures. In this paper, we propose an automatic technique for inferring fractional delay mismatches across the receive channels of cognitive radio (CR) receivers. The method leverages space‐time adaptive processing algorithms to track and compensate inter‐channel delay offsets with high precision. The proposed approach enables robust synchronization, improved receiver coherence and reliable operation in wideband CR systems where dynamic channel access is beneficial for CR systems, as it enables higher spectral efficiency. Moreover, the proposed method has a very low computational complexity and can be easily implemented on processing hardware.