NDA-EVM based Co-channel Interference Analysis in Co-frequency Network

摘要

Transmission in co-frequency network always affected by co-channel interferences. In order to achieve higher communication performance, interference elimination schemes should be applied. Thus, analysis of co-channel interference in co-frequency network becomes the core issue, which offer threshold references to the designs of interference elimination and transmission mechanism. A novel method to quantify the co-channel interference based on nondata-aided error vector magnitude (NDA-EVM) was proposed in this paper. NDA-EVM was considered as a new metric to evaluate the change of the channels. Specifically, the NDA-EVM upper bound of multiple quadrature amplitude modulation (MQAM) signal under co-channel interferences is analytically derived. Theoretical analysis and simulation experiments indicate that, the derived upper bound closely matches with the theoretical one, especially at low SNR. Moreover, the time complexity of upper bound is linear order while that of theory is square order, which means it has a quicker react when channel estimating.