The wireless channel places fundamental limitation on the performance of wirelessrncommunication network. Fading, path loss and shadowing are some of thernimpairments caused by the wireless channel, which result in significant performancerndegradation. These wireless channel impairments can be compensated byrnvarious ways such as by increasing transmit power or bandwidth.rnSince these radio resources are scarce and expensive, future wireless systemsrnshould focus on new technologies that provide high spectral efficiency, high networkrncoverage and improved link reliability. In this aspect, Multiple-Input Multiple-rnOutput (MIMO) wireless communication system; where multiple antennas arernequipped at the transceiver of the wireless link, has been considered as promisingrntechnology to meet these requirements.rnHowever, due to size, cost, and/or hardware limitations, a small handheld wirelessrndevice may not be able to support multiple antennas. As a remedy to thisrnproblem cooperative communication, where nodes cooperate to create multiplernantennas virtually, has been proposed recently. Although cooperative communicationrnprovide high network coverage and improved link reliability, the availablernrelay resources are not fully exploited due to lack of optimal signal detectionrnscheme.rnTo this end, this thesis presents a MIMO detection based cooperative wirelessrncommunication called multiple-access relay channel (MARC) and analyze thernperformance in the form of bit error rate (BER). It allows the receiver to jointlyrndetect the source and relay transmissions, to provide better diversity gain. InrnMARC, multiple sources (two in our case) transmit to a common destinationrnwith the assistance of a single relay.rnIn this scenario, a network containing two sources, a common destination and arnrelay is analyzed. Two cooperative communication schemes which include amplifyrnand forward and decode and forward employing different MIMO detectionrntechniques are investigated and results obtained from simulations with respect tornvariable relay positioning are presented.rnKeywords: Amplify-and-Forward, Bit-Error-Rate, MIMO Signal Detection, CooperativernCommunications, Decode-and-Forward, Performance Analysis, Signalto-rnNoise-Ratio, Wireless Networks, Superposition Modulation.