| 摘要 |
Method and apparatus for recovering in a receiver of a wireless communications system independent bit streams from each of two co-channel frequency modulated carriers. In the transmitter, timing for the two independent bit streams is derived from a common clock. One bit stream is placed directly on the carrier of greater power. An XOR circuit maps the two bit streams into one bit stream which is placed on the carrier of lesser power. In the receiver, an ordinary frequency demodulator provides an output consisting of the bit stream of the dominant carrier having superimposed voltage spikes. A limiter removes the spikes and provides as output the bit stream on the carrier of greater power. The peak value and the rate of occurrence of the spikes each contain information about the bit stream on the carrier of lesser power. A peak voltage detector provides an output signal which indicates the differences in the peak value of the spikes. A peak rate detector provides an output signal which indicates the rate of occurrence of the spikes. A comparator distinguishes the two peak values present and provides as an output the bit stream on the carrier of lesser power. In this manner, the two bit streams are recoverable by the operation of a series connected frequency demodulator and a peak voltage or peak rate detector.
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