Burst demodulator

Claim 1

A burst demodulator for digitally modulated signals comprising: a local oscillator for generating an autonomous predetermined carrier frequency; means, responsive to a digitally modulated radio frequency (r-f) input signal and the predetermined carrier frequency from the local oscillator, which carrier frequency is asynchronous and nominally approximates a carrier frequency used to obtain the r-f input signal, for downconverting the r-f input signal to a baseband output signal, the r-f input signal comprising a plurality of sequential bursts of information within a predetermined time period which include one or more predetermined bursts of information which are destined for the burst demodulator; means, responsive to the baseband output signal from the downconverting means, for sampling the baseband output signal at a predetermined rate which is autonomous from the bit clock of the r-f input signal and at a frequency which is at least twice that of the baseband output signal spectrum, to generate a plurality of associated analog signal samples; means for converting each of the plurality of analog signal samples from the sampling means into a separate representative digital signal, such representative digital signal corresponding to a level of each sample and not to a final determination of any discrete information digit originally modulated onto a carrier forming the digitally modulated input signals received by the burst demodulator; and means for storing each of the separate representative digital signals associated with a first predetermined burst of information destined for the burst demodulator in each frame period for subsequent slow-speed processing to recover the discrete information digits.