Resource Allocation for OFDM Systems Based On Sub-Carrier Pairing
نویسنده
چکیده
Orthogonal Frequency Division Multiplexing (OFDM) is a form of multicarrier modulation. Different symbols are transmitted over different subcarriers. The use of relays increase the coverage area, improve spectral efficiency and also the network lifetime. On the basis of the amplify and forward relaying mode, a two hop multi relay system is proposed with joint relay selection, subcarrier assignment. The subcarrier pairing enhances system performance. The resource allocation for individual power constraints and total power are solved using optimal and suboptimal algorithm. Further the system performance is improved by means of increasing the number of subcarrier pairs.
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