北斗全球系统导航信号恒包络调制和复用技术

出于以导频通道为代表的北斗全球导航卫星系统现代化信号结构升级以及后向兼容的需求,北斗系统近几年提出了多种新型恒包络调制和复用技术,包括适用于北斗系统B1频点的正交复用二进制偏移载波(QMBOC)调制和非对称双正交相移键控(ADualQPSK)调制,适用于B2频点的时分复用AltBOC(TDAlt BOC)调制与非对称恒包络二进制偏移载波(ACE-BOC)调制,适用于B3频点的双正交相移键控(DualQPSK)调制,适用于双边带任意信号路数、任意功率配比的广义恒包络二进制偏移载波(GCE-BOC)调制。本文系统性地论述了北斗全球系统中提出的多种新型恒包络调制和复用技术,在此基础上基于GCEBOC调制总结出了一种恒包络调制的统一解析表示形式,对全面理解北斗全球系统信号设计思路及在此基础上发展设计新型的恒包络调制和复用技术均能提供重要的借鉴。

Research of Constant Envelope Modulation / Multiplexing Technologies for Modern BeiDou Global Navigation Signals

For the purpose of structural enhancement and backwards compatibility, BeiDou Navigation System has proposed several new constant envelope modulations recently, including QMBOC and ADualQPSK modulations, the new MBOC modulation and constant envelope multiplexing technologies applied for B1 band; TD-AltBOC and ACE-BOC modulations, the constant-envelope modulation that multiplexes four binary spreading codes as two QPSK signals at two different carrier frequencies applied for B2 band; DualQPSK modulation, the constant-envelope modulation that multiplexes four binary spreading codes as two QPSK signals at one carrier frequency applied for B3 band; GCE-BOC modulation, the constant-envelope modulation that multiplexes arbitrary signals at two different carrier frequencies. In this paper, all the new modulations are analyzed, including several aspects such as application backgrounds, modulation principles and multiplexing efficiencies. On the basis of this, a unified analytical expression of constant envelope modulation / multiplexing is summarized based on GCE-BOC modulation, which will provide an important reference for the comprehensive understanding of the signal design of the Beidou global navigation satellite system and the development of new type of constant envelope modulation / multiplexing technology on this basis.