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“多址方式”是目前移动通信中广泛应用的技术,其基础在于信号特性上的差异。一般来说,信号的这种差异表现在某些参数上,例如信号的工作频率、信号的出现时间及具有的特定波形等。以此实现对不同用户台和基站发出信号赋予不同的特征,使基站能从众多用户台的信号中区分出是哪一个用户台发出来的信号,而各用户台也能识别出基站发出的哪个信号是发给自己的,以实现正常有序的通信。多址方式的基本类型有频分多址(FDMA)、时分多址(TDMA)和码分多址(CDMA)。下面就这三种方式进行一下比较。
The “multiple access method” is currently widely used in mobile communications technology, which is based on the signal characteristics of the differences. In general, this difference in the signal is reflected in certain parameters, such as the frequency of the signal, the time of occurrence of the signal and the specific waveform it has. In this way, different user stations and base stations can be given different signals, so that the base station can distinguish signals from many user stations from signals sent by the user stations, and each user station can also identify which one sent by the base station The signal is sent to itself to enable normal and orderly communication. The basic types of multiple access methods are Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA) and Code Division Multiple Access (CDMA). The following three ways to make some comparisons.