Quality monitor for digital audio signals includes detector sensing four error types and providing signal when at least one exceeds tolerable limits

摘要

The system provides instantaneous analysis of signal quality to determine whether acceptable stereophonic signals are being transmitted. The quality control system includes subjecting the digital audio signal (ADS) to a detection process, sensing spurious parasitic signals such as brief interruptions (101), squeal (102), hum (103) and left/right shift (104). A warning signal is produced (105, 106) if at least one of these unwanted signal components is present. The mode of transmission of the signal in either mono or stereo may be discriminated according to the result of the quality control. The detection process may include analysis of the signal within a given window or time-frame, and includes counting the number of occurrences of the parasitic signal problem within this period. The resulting value is compared with a threshold to determine whether the quality is acceptable or not.