Abstrakt

Cancellation of Interference for More Users in a Wireless Environment

Dr.T.V.U.Kiran Kumar

In this paper a multiple access channel is considered where there are four users each has its own transmit antenna and a common receiver for these four users where the receiver has four receive antennas. The users know each others channel, the precoders are designed utilizing the channel information to cancel interference at the receiver without sacrificing the diversity or complexity of the system. The precoders that are designed using the channel information makes it possible for different for the four users to transmit the signal orthogonal to each other. Then using orthogonality of the transmitted signal the common receiver can separate the signal from each user and decode the signal independently . The users transmits the data at fixed and variable rate. The modulation scheme used in this paper is QPSK and QAM techniques. The performance of the system is analyzed by comparing simulated results shown by both the modulation techniques.