Self-calibration method for Amplitude and Phase Error of MIMO system

Abstract

In intermediate frequency multiple input multiple output communication system based on AD9361, due to the random phase difference of local oscillator locking between multiple chips, as well as filtering, analog to digital/digital to analog conversion and other processing, there are amplitude and phase errors between multiple channels. To solve this problem, self-calibration method of transceiver channels is introduced. By selecting sampling data sequence and performing fast Fourier transform calculation, this method can conveniently and quickly realize the automatic calibration of amplitude and phase errors between channels, with high calibration accuracy and good signal-to-noise ratio performance. Good consistency can be obtained between channels after calibration, so as to ensure the performance of following beam forming.