Method and system for using sign based synchronization sequences in a correlation process to reduce correlation complexity in an OFDM system

A method of synchronizing with a base station by a mobile device, comprising:

• generating a complex correlation reference sequence that includes a plurality of complex correlation coefficients, each of the complex correlation coefficients including a real component and an imaginary component;
• receiving a signal from the base station that includes a Primary Synchronization Signal (PSS);
• and
• correlating the PSS of the received signal with a sequence of complex sign coefficients, the sequence of complex sign coefficients including a plurality of complex numbers that each include a real component and an imaginary component, the components having a first value when a corresponding component in the complex correlation reference sequence has a positive value and having a second value when a corresponding component in the complex correlation reference sequence has a negative value,
• wherein at least one of the above steps is performed by a processor.

A wireless communication device, comprising:

• a sequence generator configured to generate a sign-based first complex correlation reference sequence that includes a plurality of sign-based complex coefficients that each include a real component and an imaginary component, from a second complex correlation reference sequence, the components of the sign-based first complex correlation reference sequence having a first value for corresponding positively-valued components of the second complex correlation reference sequence and having a second value for corresponding negatively-valued components of the second complex correlation reference sequence;
• a receiver configured to receive a signal from the base station that includes a Primary Synchronization Signal (PSS);
• and
• a correlator configured to correlate the PSS of the received signal with the sign-based first complex correlation reference sequence.

A method of synchronizing with a base station by a mobile device, comprising:

• generating a sign-based first complex correlation reference sequence corresponding to signs of a second complex correlation reference sequence;
• receiving a signal from the base station that includes a Primary Synchronization Signal (PSS);
• and
• correlating the PSS of the received signal with the sign-based first complex correlation reference sequence,
• wherein at least one of the above steps is performed by a processor,
• wherein the generating of the sign-based first complex correlation reference sequence further includes generating a sequence of complex numbers that corresponds to a plurality of complex coefficients of the second complex correlation reference sequence,
• wherein the generating further includes, for each positively-valued real component of the second complex correlation reference sequence, setting a value of a corresponding real component of the sign-based first complex correlation reference sequence to +1, and
• wherein the generating further includes, for each negatively-valued real component of the second complex correlation reference sequence, setting a value of a corresponding real component of the sign-based first complex correlation reference sequence to −1.