A method of PRACH detection threshold setting in LTE TDD femtocell system

Abstract

Detection threshold is a crucial parameter in Physical Random Access Channel (PRACH) receiver and determines the detection performance and efficiency. A method of PRACH detection threshold setting in Long Term Evolution (LTE) Time Division Duplex (TDD) femtocell system is proposed in this paper based on theoretical analysis. This method uses the frequency domain correlation calculation results, and benefits from multiple antennas diversity combing to adjust the relative detection threshold, which is the ratio of absolute detection threshold and time varying noise level. Cumulative Distribution Function (CDF) of the relative threshold is modified to obtain the absolute threshold. Simulation results show that the proposed method fulfills the requirements of the system and gets a promotion in performance under certain false alarm probability and channel conditions.