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Now a day telephones are connected with a radio link rather than wired directly. Although the term wireless may seem a bit old- fashioned, it is about the only general name for such telephones, because terms like cordless telephones, cellular telephones, mobile telephones, and even radiotelephone have come to mean specific types of telephones without wires. In the analog system, the radio link is completed by the transmission of a carrier that is frequency modulated (FM) with the information to be transmitted. The carrier and modulation principles are the same as described for the modem. The only difference is that the frequency of the carrier is much higher for the cordless telephone. Digital communication scheme is used to extend the performance of the wireless telephone system. Various methods of modulation and standard power and frequency rating will be presented in the topic.