| Summary: | 碩士 === 國立臺北大學 === 通訊工程研究所 === 106 === With the rapid growth of 4G, the total number of LTE subscribers increased by 74% from the end of 2015 to the end of 2016. This increase has resulted in base stations experiencing heavy loads. There are three ways in which the transmission of a communication system can be increased: transmission technology, the use of bandwidth, and signal quality. However, the most direct method is the increase of transmission bandwidth; this is the same principle as widening a road to naturally accommodate more cars. Initially, 3GPP proposed the LTE-U solution. However, this solution needs to compete with the Wi-Fi 5 GHz communication band, leading to Wi-Fi camp boycott and challenges. 3GPP proposed a further solution to the resistance of the Wi-Fi camp; this program is called LTE-H. We set up a Wi-Fi base station at the edge of the cell to allow users in this location to obtain a better network speed. Therefore, the method of allocating carrier resources to the user has become an important topic. This dissertation uses the LTE-H scheme as a basis to optimize the resource allocation by means of algorithms of some downlink OFDMA systems in LTE. We set the Wi-Fi system parameters according to the iTaiwan Hotspot announced by Taiwan's Executive Yuan, in which the average internet access speed of 5 Mbps per person is set. We use two algorithms, namely particle swarm optimization (PSO) and genetic algorithm (GA). The system throughput is lower when Wi-Fi is set directly set to 5 Mbps and the GA algorithm is better than the PSO algorithm. If Wi-Fi uses algorithms to allocate resources, the system throughput is not much worse; however, the throughput is too high and does not match the reality. In our opinion, the GA algorithm can achieve a better throughput than the PSO algorithm in reality.
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