| 摘要 |
A digital data modulator includes a source of a plurality of digital data signals having a common data bit period. A plurality of encoders each encode a corresponding one of the plurality of digital data signals using a variable pulse width code having edges occurring in respective non-overlapping intervals within the data bit period. A plurality of pulse signal generators each generate respective pulses representing the edges of the corresponding one of the encoded plurality of digital data signals. A carrier signal generator generates a carrier signal having carrier pulses corresponding to the respective pulses. A digital data demodulator includes a source of a modulated signal including successive bit periods, each bit period having a plurality of non-overlapping intervals respectively associated with corresponding intervals in successive bit periods, each interval containing a carrier pulse, spaced relative to carrier pulses in other associated intervals, representing a corresponding variable pulse width encoded digital data signal. A detector demodulates the modulated signal to generate pulses corresponding to received carrier pulses. A plurality of decoders each decode pulses received in a respective one of the plurality of associated intervals in the bit period to generate the corresponding digital data signal. |
