PIPE-LINED SUCCESSIVE INTERFERENCE CANCELLATION UNIT FOR CODE DIVISION MULTIPLE ACCESS SYSTEM

摘要

PURPOSE: A pipe-lined successive interference cancellation unit for a code division multiple access system is provided to reduce decoding delay without increasing bit error rate in the structure of a multistage by pipe-lining. CONSTITUTION: A power ordering machine(100) determines the order of signals(r(t)) received for the first time via a channel in response to a receiving signal power of each user. A time delay unit(110) delays the received signals(r(t)) for a predetermined time(Tb) through four unit delay units sequentially. Unit interference cancellation units(ICU) of a number of pipelines by users performs a dispersion operation according to time delayτk responding to power ordering information outputted from the power ordering machine, an estimated value of phase offsetΦk and a dispersion code ck(t) and outputs a regenerative signal through a soft decision function and a hard decision function. A plurality of accumulators(120) filters out only the signal of the corresponding user from delayed receiving signals(r(t)) each outputted from a unit delay unit of the time delay unit(110).