Patent ID: 7805294

Claim:
A wireless communication apparatus comprising: speech data generating means for generating digitally-encoded speech data from an incoming speech signal; frame data generating means for generating transmission data having a frame structure including an area used to transmit the speech data generated by the speech data generating means as n-level symbol speech data, where n is an integer equal to or greater than 2; FSK modulation means for generating an FSK modulated signal corresponding to the transmission data generated by the frame data generating means by n-level FSK modulating carrier wave, where said FSK modulated signal having any level of n-level FSK modulation is generated by modulating said carrier wave; transmission means for transmitting the modulated signal generated by the FSK modulation means to an external device at a predetermined wireless frequency band; and sound presence/absence detecting means for detecting a sound presence interval and a sound absence interval of the incoming speech signal, and wherein said frame data generating means replaces the speech data generated by the speech data generating means at the sound absence interval detected by said sound presence/absence detecting means with non-modulation setting data including symbol data having a level other than n-level symbol; and wherein said FSK modulation means outputs the non-modulated carrier signal in response to said non-modulation setting data in the frame data.