Joint Parabolic Interpolation and Barycenter Calibration of Spatial Spectra—A High Precision Sensing Solution With Near-Field MIMO Systems

Next-generation mobile communication systems will employ higher frequency bands and larger antenna arrays to meet the growing demand for data rates. However, this shift will extend the Rayleigh distance, resulting in near-field effects. Traditional far-field algorithms for source sensing yield considerable errors under these conditions. Near-field spatial spectrum estimation algorithms require multi-dimensional spectral peak searches, which lead to high computational complexity and necessitate a trade-off between sensing accuracy and real-time performance. Consequently, there is an urgent need for high-precision, low-complexity algorithms suitable for near-field sensing. This study proposes a calibration algorithm for spectral peak searches in near-field spatial spectra, referred to as the joint parabolic interpolation and barycenter calibration (PI-BC) algorithm. Simulation results indicate that, compared to existing parameter estimation algorithms, the joint PI-BC algorithm significantly improves sensing accuracy. Furthermore, the computational complexity of the calibration process in the joint PI-BC algorithm is negligibly low.