Patent ID: 8548078

Claim:
Circuitry for generating a plurality of ranging codes, the circuitry comprising: shift register circuitry; receiver circuitry configured to receive a ranging code; identification circuitry configured to identify a group type associated with the received ranging code based, at least in part, on whether the received ranging code is received during a time slot reserved for the identified group type; sequence retrieval circuitry configured to: receive an initial sequence corresponding to the identified group type; and apply the initial sequence to the shift register circuitry; and after applying the initial sequence to the shift register circuitry, provide an input signal to the shift register circuitry at a plurality of time instants, wherein a value of the input signal at a time instant of the plurality of time instants is based on a plurality state values in the shift register circuitry at a previous time instant; and clocking circuitry configured to clock the shift register circuitry at the plurality of time instants to output, in a consecutive sequence, the plurality of ranging codes corresponding to the identified group type.