Mitigation of interference in cell search by wireless transmit and receive units

A wireless transmit/receive unit (WTRU) comprising:

• a code correlator configured to correlate a received signal with a primary synchronization code;
• an auxiliary code correlator having a substantially similar length as the code correlator configured to correlate the received signal with a code having a low cross correlation with the primary synchronization code;
• and
• a scaling circuit configured to scale an output of the code correlator by an output of the auxiliary code correlator.

A method for cell search in code division multiple access (CDMA) communications which utilize a primary synchronization code (PSC) transmitted at a predetermined chip rate, the method comprising:

• sampling received wireless communication signals at a rate N times faster than the predetermined chip rate where N is a positive integer to produce samples;
• splitting the samples into N streams of different samples such that for each successive set of N samples, an nth sample is assigned to a corresponding nth stream of samples for n equals 1 to N;
• for each sample stream, generating correlation values by correlating with a PSC;
• generating noise estimates with respect to one of the sample streams;
• using respective correlation values and noise estimates to produce threshold comparison values with respect to each sample stream;
• and
• detecting a chip offset based on the threshold comparison values.

A wireless transmit receive unit (WTRU) configured for use in code division multiple access (CDMA) communications which utilize a primary synchronization code (PSC) transmitted at a predetermined chip rate, the WTRU comprising:

• a sampling component configured to sample received wireless communication signals at a rate N times faster than the predetermined chip rate where N is a positive integer to produce samples;
• a splitter configured to split the samples into N streams of different samples such that for each successive set of N samples, an nth sample is assigned to a corresponding nth stream of samples for n equals 1 to N;
• processing circuitry configured to generate correlation values for each sample stream by correlating with a PSC;
• the processing circuitry configured to generate noise estimates with respect to at least one of the sample streams;
• the processing circuitry configured to use respective correlation values and noise estimates to produce threshold comparison values with respect to each sample stream;
• and
• the processing circuitry configured to detect a chip offset based on the threshold comparison values.