一种低轨卫星跳频通信同步捕获方法  

Synchronization Capture Method for Frequency Hopping Communication System on LEO

作　　者：刘春玲[1] 刘照舵 刘海燕[1] 

机构地区：[1]大连大学信息工程学院,辽宁大连116622

出　　处：《计算机仿真》2014年第3期87-91,共5页Computer Simulation

基　　金：国家863计划项目(2012AAXX);辽宁省教育厅科学研究项目(L2012440;L2012217)

摘　　要：在低轨卫星通信同步优化问题的研究中,跳频同步技术是跳频通信技术的关键。将跳频通信体制引入到卫星通信中,可以提升卫星通信的抗干扰能力。在一定范围内多普勒频偏对同步捕获性能具有一定的影响,为了满足低轨卫星与地面站之间高速跳频通信系统的同步要求,提出了基于多普勒频偏补偿的同步头与时间信息相结合的跳频同步快速捕获方法,设计了同步序列格式。改进方法采用多普勒频偏补偿方式对存在多普勒频偏的跳频同步头信息进行捕获,包括信号载波频率的捕获和多普勒频偏的前导序列相关码的提取,通过搭建跳频同步捕获方案仿真系统,验证了用跳频同步捕获方法提高了同步性。仿真结果表明,在多普勒频偏一定范围内,改进方法在低轨卫星与地面站之间的跳频通信系统中,具有同步时间短、捕获峰值大、捕获概率高、虚警概率低的性能优势。Frequency-hopping （FH） synchronization is the key for frequency-hopping communication technolo- gy. A frequency-hopping communication system was introduced into the satellite communications, and which can en- hance the ability of anti-interference in the satellite communications. The Doppler frequency offset within a certain range has an effect on the capture for synchronization between LEO satellite and ground station. In order to meet the requirements of synchronization of high-speed frequency hopping communication system, a quick Frequency-hopping acquisition method which combines the synchronization head and time of day （TOD） and is based on the Doppler fre- quency offset compensation has been proposed and the synchronization sequence pattern has been designed in this pa- per. The method uses the Doppler frequency offset compensation to capture for the frequency-hopping（FH） synchro- nization-head with Doppler frequency offset, including the capture for the signal carrier and extracting the preamble code sequence with the Doppler frequency offset. Also, this paper verified the synchronization acquisition method of hopping synchronization performance by building the simulation system of hopping synchronization acquisition pro- gram. The simulation results show that under the Doppler frequency offset within a certain range, the method in the frequency hopping communication system between the LEO satellite and ground station has the advantage of short syn- chronization time, great capture peak value, c high apture probability, and low false probability.

关 键 词：跳频 同步捕获 同步头 多普勒频偏 

分 类 号：TP301.6[自动化与计算机技术—计算机系统结构]