Patent ID: 7688878

Claim:
An apparatus for detecting a preamble in a burst-type spread-spectrum communications system, the device comprising: means for determining channel signal and noise features; means for performing a normalized peak-to-average ratio (PARN) test using the channel signal and noise features, wherein the means for performing the PARN test includes means for determining an outer code matched filter peak-to-average output value, means for normalizing said value by a time-averaged signal-to-noise ratio, and means for comparing said normalized peak-to-average ratio against a threshold value; means for performing a transition signal-to-noise ratio (SNR) test using the channel signal and noise features, wherein the means for performing the transition SNR test includes means for determining a ratio between an instant and a delayed time-averaged signal-to-noise ratio and comparing said ratio between an instant and a delayed time-averaged signal-to-noise ratio against a threshold value; and means for generating a preamble detection indication if the PARN test and the transition SNR test pass, wherein generating the preamble detection indication is disabled during a transition period at an onset of an arrival of the preamble.