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CDMA是Code DivisionMultiple Access的英文缩写,中文翻译为码分多址。CDMA是用于数字蜂窝移动通信的一种先进的无线扩频通信技术,它能满足近年来运营者对大容量、廉价、高质量的移动通信系统的需求。CDMA技术作为一种抗干扰的通信手段,很早就在军事通信中得到了应用,但是将CDMA技术应用于民用的数字蜂窝移动通信系统,还是20世纪80年代末才由美国高通(Qualcomm)公司实现的。QCDMA系统中采用了许多先进的技术,保证了系统性能的优势,其标准称为IS-95系列,其中包含多个标准。多径衰落是移动通信系统需要克服的主要问题,CDMA系统采用了多种形式的分集,从而很好地解决了这一问题。CDMA系统采用符号交织、检错和纠错编码等方法实现了时间分集;
CDMA is the English abbreviation of Code Division Multiple Access, Chinese translates as code division multiple access. CDMA is an advanced wireless spread-spectrum communication technology used for digital cellular mobile communication, which can meet the operators’ demands for large-capacity, low-cost and high-quality mobile communication systems in recent years. As an interference-resistant means of communication, CDMA technology has long been used in military communications. However, the application of CDMA technology to civilian digital cellular mobile communication systems was not achieved until the late 1980s by Qualcomm Achieve. The QCDMA system incorporates many advanced technologies that ensure system performance advantages, and its standard is called the IS-95 Series, which contains several standards. Multi-path fading is a major problem that mobile communication systems need to overcome. The CDMA system uses various forms of diversity to solve this problem. CDMA system uses symbol interleaving, error detection and error correction coding methods to achieve time diversity;