| The growing need for mobile services and the scarceness of spectrum added to this the feature of the large mobile operator, need that in the future wireless systems furnish a higher peak data rates and better Quality of service specifically for the cell border users.Further more it is important that they reach high spectral efficiencies and they are readily deserved. In order to accomplish these goals, mobile systems use to integrate technologies that enhance the cell throughput without raising spectral consumption. LTE-A is a substitute of LTE that 3GPP has itemized. LTE-A has been presented as a better candidate to tackle high spectral productivity problem,in addition LTE is based on OFDMA on downlink and uplink. LTE-A includes as well several important technologies such as Carrier Aggregation(CA), MIMO, relay and Coordinated Multipoint transmission and reception.This report relates on enhancing the performance of the users located at the cell border in LTE-Advanced networks.To reach this goal this thesis uses both relay and coordinated multi-point transmission and reception technologies. In one hand,3GPP-LTE has introduced relay as a technology to improve the transmissions between two positions on a radio path and also to enlarge the cell coverage. In the other hand coordinated multi-point transmission and reception is a multi-cell processing technique proposed to tackle the inter-cell interference and enhance spectral efficiency for users on the cell border which suffer for performance degradation caused by the inter-cell interference.For the purpose illustrates previously, this work begins with studying the capacity aspect of the relay node performance.It used first Amplify and Forward and Decode and Forward relay mode and it also investigates both Half Duplex and it introduced a novel Full Duplex, which has not been less, took into account by 3GPP-LTE-Advanced. The thesis also investigated their performance comparison.3GPP has preferred the utilization of the Relay Node (RN) because of the cost effective, throughput enhancement and coverage extension. In this report, the numerical and simulation results testify that the capacity of Half Duplex with Amplify-and-Forward relaying (HDX AF) is better than the capacity of the one with Decode-and-Forward relaying (HDX DF), but also that the Full Duplex capacity of Amplify-and-Forward relaying mode (FDX AF)is better than the Full Duplex Decode-and-Forward relaying scheme (FDX DF).The report shows that Full Duplex scheme attains almost the double of the Half Duplex relaying performance and a multi-antenna receiver gains more from relaying than a single-antenna receiver. In the perfect Relay Link, Decode-and-Forward relaying performance is better than the one with Amplify-and-Forward in terms of capacity.The reason is because Decode-and-Forward scheme does not forward noise.To continue, it uses the pre-coding technique over the coordinated base station to achieve instantaneous multi-user transmissions over the same frequency band.The main work of this report is to investigate the possibility of using relaying and coordinated multi-point transmission in one instead of having them as a separate transmission techniques.In fact, in the purpose of reaching a high spectral efficiency with improved peak data rates of cell border users and enabling an improved network coverage with better quality throughput in downlink and uplink, LTE-A introduced Coordinated Multi-point Transmission and relaying techniques separately. Therefore, we thought about a novel transmission mode, which is putting in one relaying and Coordinated Multi-point Transmission techniques.The numerical results show that the new transmission scheme provides better solutions for enhancing the performance of the user located on the cell border. This new cooperative mode can also simultaneously transmit to several users in another cells and reach better sum-rate capacity than the systems, which apply the two transmissions scheme separately.
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