Antenna Port Number Detection Algorithm Based on Channel Estimation in LTE System

Various pioneering approaches have been proposed for antenna port number detection, which usually apply blind detection to obtain the number of antenna ports before passing the cyclic redundancy check (CRC), resulting in the generation of redundant calculations and delays. To solve this problem, we propose an antenna number port detection algorithm based on channel estimation. Instead of applying traditional channel estimation techniques, we build a channel estimation method based on phase rotation that quantifies the phase difference between different Cell-specific Reference Signals(CRS) of the same subcarrier. Then we use this method to perform channel estimation by means of phase compensation. On this basis, we propose a novel technique to determine the number of antenna ports, with the purpose of obtaining the matching degree between phase rotation and linear regression model by considering the influence of frequency offset and delay for channel estimation. The algorithm has high correct rate, low complexity, low latency and excellent anti-offset performance. The theoretical analysis and simulation results show that the proposed algorithm can achieve a median latency of 12.3ms. Moreover, it holds a high detection success rate when the signal frequency offset is 1kHz.