基于单光子探测器恢复时间的误码率分析

Analysis of BER model of single-photon detector recovery time

摘要:

在深空激光通信中，为满足通信距离远、传输速率高的要求，常采用脉冲位置调制（Pulse Position Modula-tion， PPM）与单光子探测器（Single-Photon Detector， SPD）相结合的探测体制。本文从单光子探测器的恢复时间特性出发，推导了探测器单元探测概率和虚警概率模型，建立了基于信号或硬判决和最大计数硬判决的多元单光子探测器阵列误码率模型。仿真分析结果表明：在16-PPM调制和RS（15，8）编码（Reed-Solomon Codes，里德-所罗门编码）体制下，为实现1.22 Gbps的通信速率、误码率优于10^-7，当探测器单元数为4时，探测器恢复时间应≤3.2 ns；当探测器单元数为25时，探测器恢复时间应≤10 ns。

Abstract:

In deep space laser communication, in order to meet the requirements of long communication distance and high communication rate, the detection system combining PPM and single-photon detector is often used. Starting from the recovery time characteristics of single-photon detectors, this paper derives the detector unit detection probability and false alarm probability models, and establishes a multivariate single-photon detector array BER model based on signal “or” hard judgment and maximum count value judgment. Simulation analysis results show that in the 16-PPM and RS(15,8)coding system, in order to achieve a rate of 1.22 Gbps, the BER is better than 10^-7 communication, when the number of detectors is 4, the detector recovery time should be equalor less than 3.2 ns, when the number of detector units is 25, the detector recovery time should be equalor less than 10 ns.