Asymmetrical forward/reverse transmission bandwidth

摘要

A wireless communications system employs code-division multiple access information transmission techniques where the uplink and downlink transmission bandwidths are unequal. The higher bandwidth is an integer multiple of the lower bandwidth. The present system requires a base station and a subscriber unit to have two pseudo-random code generators which can be clocked separately. Alignment of the uplink and downlink pseudo-random spreading codes is achieved by truncating the code sequence for the lower speed link at the conclusion of a complete code sequence for the higher speed link.

主权项

1. A wireless terminal for use with a code division multiple access (CDMA) wireless network, comprising:
a processor, wherein the processor controls operation of the wireless terminal including by spreading a signal with at least one output code sequence for transmission through a wireless medium; a radio front end, wherein the radio front end modulates at least one carrier with the spread signal; and a sequence generator circuit coupled to the processor and the radio front end, wherein the sequence generator circuit provides the at least one output code sequence, wherein the sequence generator circuit provides the at least one output code sequence as a combination of a first pseudo-random sequence and a portion of a second pseudo-random sequence, the second pseudo-random sequence having a length greater than a length of the first pseudo-random sequence, wherein the first pseudo-random sequence and the portion of the second pseudo-random sequence are in alignment by truncation of the second pseudorandom sequence at a conclusion of the first pseudo-random sequence, and wherein the length of the first pseudo-random sequence and a length of the portion of the second pseudo-random sequence are equivalent, and the length of the portion and a length of the at least one output code sequence are equivalent.