DOWNLINK JOINT DETECTION METHOD OF COMMUNICATION SYSTEM AND DEVICE THEREOF

摘要

PURPOSE: A downlink joint detection device of a communication system is provided to reduce calculations of an inverse matrix operation of a JD(Joint Detector) when using the JD in a downlink receiver, thereby lowering entire complexity of the receiver, improving downlink capacity, and reducing power consumption of a terminal. CONSTITUTION: A QPSK modulator(301) modulates a data sequence of the first user to a QPSK signal. A CDMA spreader(302) spreads the QPSK signal by a spreading code of the first user. A QPSK modulator(311) modulates data sequences of a K user to QPSK signals in the same method as the first user. A CDMA spreader(312) spreads the QPSK signals by a spreading code of the K user. The spread signals of each user are added to a chip level in an adder(313), and are scrambled by an inherent scramble code of a base station in a scrambler(314). The scrambled signals are filtered by an RRC(Root Raised Cosine) filter(315), and are transmitted. The transmitted signals are added with white Gaussian noise in an adder(317), and are received to a receiver via a multi-path fading channel(316).