Multiple target data receiver for a collision avoidance system

Claim 1

In combination, means for receiving reply signals generated by remote stations in response to probe signals from interrogating stations, said reply signals being adapted to be received in an environment wherein signals of a type different from said reply signals may be received, all of said received signals being of predetermined duration and having a characteristic indicia of either a binary logic value of one or zero, means for detecting said received signals and generating therefrom digital signals representing a binary bit corresponding to said logic value, means for sampling said digital signals and generating therefrom a plurality of sampled signals, each sampled signal having a duration substantially less than said predetermined duration, and means for comparing the relative duration of sampled signals of one logic value with that of sampled signals of the opposite value to generate a multi-bit digital output signal manifesting a first or second binary logic value, which corresponds to that of a valid received reply signal, in accordance with the longer of said compared sampled signals or manifesting a third binary logic value, which corresponds to the absence of a valid received reply signal, when the duration of said compared sampled signals is equal.