| 摘要 |
According to the present method, the signal received in SSB is, after intermediate frequency shifting IFC, sub-sampled SH and digitised ADC. It is then baseband shifted on two quadrature channels I, Q by multiplication on each of the channels MI, MQ by a numerical sequence representing the quadrature sine wave, then it is filtered by means of a complex filter CF affording selectivity thereof, the coefficients of the filter determining the selection of the upper or lower band, the real part I' of the complex signal at the output of the complex filter is finally converted DAC to give the demodulated audio signal DSS. The purely digital functions can be carried out advantageously by a signal processor capable of working in complex mode. Application: SSB or LLB signal demodulation. <IMAGE>
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