| 摘要 |
<p>A SAW stabilized FSK transmitter that is tuned by a varactor diode to particular center operating frequencies so as to distinguish between a '0' bit and a '1' bit. In one embodiment, a microprocessor applies an N-bit output signal to a digital-to-analog converter to alter the voltage applied across the varactor diode, and thus the center operating frequency of the transmitter. In an alternate embodiment, the microprocessor adjusts the duty cycle of a pulse-width modulation signal so as to change the voltage potential applied to the varactor diode.</p> |
