The cellular digital packet data (CDPD) is a system which borrows idle radio channels from the existing cellularmobiletelephone networks for packet data transmission.
蜂窝数字分组数据(CDPD)是利用现有的模拟蜂窝电话网来传输数据的一种新技术。
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They go by various names — cellulartelephone, cell phone, mobile, wireless, handy — and an estimated four billion people use them worldwide.