Throughput analysis of CMIMOR in a FDMA/TDMA multi-cell system

To be able to meet the expected higher traffic load in the future the capacity in the networks needs to be higher. This is preferably done in the most cost efficient way as possible. Using traditional system tends to be very cost consuming and therefore new kinds of systems are evolving like multi-hop systems, relaying networks or MIMO networks. In this thesis a special kind of relaying network is investigated called Cooperative MIMO Relaying (CMIMOR) and it can be seen as hybrid between a MIMO network and a relaying network. The aim of this thesis is to compare the throughput from a radio network using CMIMOR technique with the throughput from a traditional single-hop cellular network with beamforming. The study is done for the downlink in a multi-cell TDMA/FDMA system, assuming that each cell contains only one active user. For the CMIMOR network two results are presented, due to two different power allocation algorithms for the chosen relays. From the results it can be concluded that no major differences between the two power allocation algorithms can be seen, and that the CMIMOR network is outperformed by the beamforming network. To be able to compete against the beamforming, the relaying slots within the cells must be reused and the transmissions cooperated for the different relays, minimizing the interference. An heuristic view of this relay reuse is presented and concludes that at least two relaying groups must be able to transmit within the cell at the same time causing minimal interference for the CMIMOR to be effective in this specific system.