Method for searching pilot signals to synchronize a CDMA receiver with an associated transmitter
First Claim
1. A method of searching for, and optimizing reception of, a pilot signal in a CDMA wireless communication system, comprising the steps of:
- setting an antenna to a receiving pattern;
loading a frequency offset stored in an offset memory;
setting a pseudorandom number (PN) sequence offset to zero;
detecting a signal from the antenna and comparing a magnitude of the signal to a threshold;
changing the PN offset by a predetermined offset increment if the magnitude is less than the threshold;
determining if a PN epoch is beginning and, if so, determining if a significant pilot signal is present for the frequency offset, PN offset, and antenna receiving pattern; and
ending the method if a pilot signal of sufficient magnitude is detected.
0 Assignments
0 Petitions
Accused Products
Abstract
A method for synchronizing a CDMA receiver to a transmitter when an adaptive antenna is utilized to receive transmitted data, wherein a receiving antenna system is adapted between a 360° reception angle pattern (i.e., an omni-directional pattern) and a fixed reception angle (i.e., a directional pattern) by permitting the receiver to identify a pilot signal having the largest magnitude. The receiver minimizes interference from other pilot signals by steering antenna pattern nulls toward other transmitters. As a result, the time required for the receiver to acquire a valid pilot signal is significantly reduced.
-
Citations
10 Claims
-
1. A method of searching for, and optimizing reception of, a pilot signal in a CDMA wireless communication system, comprising the steps of:
-
setting an antenna to a receiving pattern; loading a frequency offset stored in an offset memory; setting a pseudorandom number (PN) sequence offset to zero; detecting a signal from the antenna and comparing a magnitude of the signal to a threshold; changing the PN offset by a predetermined offset increment if the magnitude is less than the threshold; determining if a PN epoch is beginning and, if so, determining if a significant pilot signal is present for the frequency offset, PN offset, and antenna receiving pattern; and ending the method if a pilot signal of sufficient magnitude is detected. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. An apparatus for searching for, and optimizing reception of, a pilot signal in a CDMA wireless communication system, comprising:
-
a steerable antenna comprising a plurality of antenna elements; phase shifters coupled to respective antenna elements for steering the antenna and setting the antenna to an omnidirectional pattern; a processing circuit comprising a pseudorandom noise (PN) sequence generator and configured to receive and process a signal from the antenna; a threshold circuit configured to set and adjust a threshold and determine if the processed signal exceeds the threshold, and a searching circuit configured to search for, and optimize detection of, the pilot signal in the processed signal. - View Dependent Claims (10)
-
Specification