Abstract: A digital signal processing method for real-time processing of narrow band signals to provide for reconstitution of dynamic amplitude and harmonics beyond the passband. The method utilizes a digital microprocessor implementing a digital algorithm upon a digitized sample of the analog signals. After processing digital-to-analog conversion circuitry may be used to reconvert the processed digital signal into a processed analog output signal for further use. The digital processing effectively provides a primary voltage compressor (PVC) function for processing signals in m different frequency sub-bands by gain factors, and a summing function for digitally summing the gain products so realized, to provide a primarily compressed signal. The processing method then further effectively provides a secondary dynamic voltage compressor (SDC) function for processing the PVC signal in within n different frequency sub-bands by digitally multiplying signals with each of such sub-bands by gain factors.

Abstract: A signal processing system is disclosed for processing dynamically varying intelligence-carrying signals represented by different frequencies by transferring these signals within a pass band narrower than the range of the frequencies. The system, although not a compressor or compandor system, makes use of a compressor circuit for compressing only signals within a predefined pass band. Active filter circuits shape the compressed signals into a predetermined power envelope having fundamental frequency signal components and harmonically related constituents of the fundamental frequencies. Another compressor circuit is used for further compressing signal constituents of the power envelope. A negative feedback arrangement provides dynamic limiting of compression by the first compressor circuit as a function of increase of compression by the second compressor circuit.