Patent ID: 8416886
Filing Date: 2013-04-09
Classification: H03K,H04L

Abstract:
1. An apparatus comprising: an input circuit; intermediate circuitry that is coupled to the input circuit and that outputs baseband signal; a reference signal generator that provide a reference signal; a comparator that is coupled to the reference signal generator and the intermediate circuitry so as to compare the baseband signal to the reference signal to generate a digital output signal; a first setting circuit that provides a first setting signal to the reference signal generator, wherein the first setting signal sets the reference signal to a first level; a second setting circuit that provides a second setting signal to the reference signal generator, wherein the second setting signal sets the reference signal to a second level, and wherein the second setting circuit outputs the second setting signal when the second setting circuit receives a count signal that indicates that a preamble in the baseband signal is present; and a counter that is coupled to the comparator and the second setting circuit, wherein the counter counts the pulses of the digital output signal, and wherein the counter outputs the counter signal to the second setting circuit that indicates that the preamble in the baseband signal is present.