A green quasi-dynamic frequency resource division method for LTE-A relay systems

Due to the introduction of wireless relays, the performance of LTE-A system was enhanced. Meanwhile, more energy was expensed and more interference was brought in. This is because the frequency used by relays may be the same or adjacent with the other relays or base stations. And the more stations deployed in a cell, the more energy consumed. In this paper, we proposed a novel green quasi-dynamic frequency resource division method for OFDMA download link. This method is suitable for the situation where the frequency resources are not continuous. And the special idle resources within cell are quasi-dynamically allocated, according to the load situations of base station and relays, to make the frequency division variable. With the uniform division and reasonable allocation based on the distribution of stations, the co-channel and adjacent-channel interference can be decreased effectively. Moreover, if possible, the relay stations with little users´ access can be switched off and these users will be served by the adjacent relays, so that the energy consumption can be reduced further and some interference can also be eliminated.