NOISE THRESHOLD ESTIMATOR FOR MULTICHANNEL SIGNAL PROCESSING

A noise threshold estimator for use in a high signal density environment defines a noise threshold level for a plurality of frequency divided channels such that X number of said channels will be defined as being active channels and the remaining channels as being inactive. Using a novel closed loop feedback technique to define a noise threshold level, the noise threshold estimator first compares the signal level of each incoming channel with an analog threshold voltage. A logic device counts the number of active channels and then scales that number according to a predetermined scaling function. The scaled binary number is added with the noise threshold level from the previous clocked interval to define a new noise threshold level. This binary noise threshold level is converted into an analog voltage and fedback to the feedback input of the noise comparison devices to be compared with the signal level of each incoming channel.