Disclosed is a system and method for reducing a bit-depth requirement for
an A/D converter in a GPS receiver having an antenna for receiving an
analog input signal and a low noise amplifier for amplifying the input
signal, comprising a filter for filtering about a bandwidth B the
amplified signal; a down-conversion module centering the frequency of the
filtered signal about a center frequency f.sub.0; an automatic gain
controller (AGC) for setting a set point of the input signal; an adder
for adding noise to the gain controlled signal, said noise based upon the
bandwidth B and center frequency f.sub.0; and an analog to digital (A/D)
converter for converting the added noise signal to a digital signal,
wherein the noise added to the gain controlled signal reduces the bit
depth requirement of the A/D converter.