时频资源限定条件下多用户通信独立地址码数目上限分析

Analysis of the Number Upper Limit of Independent Address Codes in Multi-User Communication with Limited Time-Frequency Resources

时分多址、频分多址、码分多址是多用户通信体制中最常见的通信传输资源共享分配方式,在传统通信系统中通常将其独立区分与各自设计,并没有考虑相互之间的本质联系。针对这一问题,基于通信系统时频资源的不同划分方式,从理论模型上分析了时分多址与频分多址之间的关联性,时分多址与直接序列扩频码分多址之间的关联性,以及频分多址与跳频扩频码分多址之间的关联性,展现了上述三种多址方式在通信时频资源划分上的不同特点和信号表征方式的等价性,指出了多用户通信中独立地址码数目的上限等于该组信号所占据的时频域的时带积。从而为通信传输中的多址理论研究与多址通信工程应用设计提供了重要参考。

Three multiple access modes,including time division,frequency division,code division,are the most common ways to share and allocate communication resources in the multi-user system.In the traditional communica-tion system,they are usually separated and designed independently without considering their essential relationship.In this paper,the different division approaches of time-frequency resources in communication system are considered.The relevance between TDMA and FDMA,the relevance between TDMA and CDMA with DSSS,the relevance between FDMA and CDMA with FHSS are analyzed from the theoretical model.The different characteristics of communication time-frequency resources division and the equivalence of signal representation for these multiple access methods are shown.It is pointed out that the number upper limit of the independent address codes is equal to the time band product of time-frequency domain occupied by the signal group.It provides an important reference for the research of communication multiple access theory and the engineering design of multiple access communication system.