Abstract A receiver in a spread spectrum communication system includes: a noise detector for detecting noises of a spread spectrum input signal; an initial synchronization circuit including a correlator for detecting a correlation of the spread spectrum input signal, a detector circuit for detecting an output of the correlator, and a comparator for receiving an output of the detector circuit and outputting a correlation detection signal; a synchronization holding circuit for receiving the correlation detection signal to perform synchronization holding and outputting a synchronization holding signal during the synchronization holding; and a control circuit for detecting if the synchronization holding signal is outputted within a predetermined period, and if not, controlling a reference voltage to be supplied to the comparator in accordance with the noise detection output of the noise detecting means.
A receiver in a spread spectrum communication system comprising: an initial synchronization circuit including a correlator for detecting a correlation of the spread spectrum input signal, a detector circuit for detecting an output of said correlator, and a comparator for receiving an output of said detector circuit an outputting a correlation detection signal; a synchronization holding circuit for receiving the correlation detection signal to perform synchronization holding and outputting a synchronization holding signal during the synchronization holding; noise detecting means for detecting noises of the correlation detection signal; and a control circuit for detecting if the synchronization holding signal is outputted within a predetermined period, and if not, controlling a reference voltage to be supplied to said comparator in accordance with the noise detection output of said noise detecting means.
Claim 2
Dependent Claim
130 words
A receiver in a spread spectrum communication system comprising: an initial synchronization circuit including a correlator for detecting a correlation of the spread spectrum input signal, a detector circuit for detecting an output of said correlator, and a comparator for receiving an output of said detector circuit an outputting a correlation detection signal; a synchronization holding circuit for receiving the correlation detection signal to perform synchronization holding and outputting a synchronization holding signal during the synchronization holding; noise detecting means for detecting noises of the correlation detection signal; and a control circuit for detecting if the synchronization holding signal is outputted within a predetermined period, and if not, controlling a reference voltage to be supplied to said comparator in accordance with the noise detection output of said noise detecting means.
Claim 3
Dependent Claim
37 words
A receiver according to claim 1 further comprising reference voltage generating means for generating a plurality of reference voltages, one of the reference voltages being selectedly applied to said comparator under the control of said control circuit.