CDMA是一种扩频通信技术,扩频就是将数字信号扩展到一个比一般的通信技术宽的多的频带上传送,即将需传送的具有一定信号带宽信息数据,用一个带宽远大于信号带宽的高速伪随机码进行调制,使原数据信号的带宽被扩展,再经载波调制并发送出去。接收端由使用完全相同的伪随机码,与接收的带宽信号作相关处理,把宽带信号换成原信息数据的窄带信号即解扩,以实现信息通信。值得注意的是第三代移动通信将以CDMA制式为无线空中接口标准已经得到了移动通信业界的公认。 CDMA is a spread spectrum communication technology, spread spectrum is the digital signal is extended to a wider than the average communication technology to send the frequency band, to be transmitted with a certain signal bandwidth information data, with a bandwidth much larger than the signal bandwidth High-speed pseudo-random code modulation, the original data signal bandwidth is expanded, and then modulated by the carrier and sent out. The receiving end uses the same pseudo-random code, correlates with the received bandwidth signal, and replaces the wideband signal with the narrow-band signal of the original information data to realize the information communication. It is noteworthy that the third generation of mobile communications will be the CDMA standard wireless air interface standards have been recognized by the mobile communications industry.