| 摘要 |
Apparatus and method for programmably phase shifting an audio tone is disclosed for use in a cellular communications system. A digital phase lock loop (PLL) includes a programmable phase shift therewithin and an audio output, phase-shifted from an input audio tone, is extracted from the thus programmed PLL. The apparatus of the present invention is particularly designed to be realized using digital circuits capable of integration into a monolithic CMOS IC. |
