The present invention provides a new baseband integrated circuit (IC)
architecture for direct sequence spread spectrum (DSSS) communication
receivers. The baseband IC has a single set of baseband correlators
serving all channels in succession. No complex parallel channel hardware
is required. A single on-chip code Numerically Controlled Oscillator
(NCO) drives a pseudorandom number (PN) sequence generator, generates all
code sampling frequencies, and is capable of self-correct through
feedback from an off-chip processor. A carrier NCO generates corrected
local frequencies. These on-chip NCOs generate all the necessary clocks.
This architecture advantageously reduces the total hardware necessary for
the receiver and the baseband IC thus can be realized with a minimal
number of gate count. The invention can accommodate any number of
channels in a navigational system such as the Global Positioning System
(GPS), GLONASS, WAAS, LAAS, etc. The number of channels can be increased
by increasing the circuit clock speed.