使用基因演算法優化室內分散式多天線系統之通道容量的佈建方式研究

Indoor DAS LOS WLAN Deployment with Channel Capacity Optimization Using GA

Nothando(Nothando)

指導教授 ： 林信標

國立臺北科技大學/電資學院/電資碩士班/碩士(2014年)

https://doi.org/10.6841/NTUT.2014.00622

摘要

WLAN networks have become very popular means for providing a wireless networking facility for home users, educational institutions, companies etc. due to their ease of installation, flexibility and their high data rate provision, apart from providing, albeit limited, mobility to users. As the environment under which these WLANs operate greatly influences their performance due to free space path loss, shadowing, multipath propagation, which result in weak received signal strength (RSS) at the receiver, a lot of research has been made to address this issue, that is. One technique to boost the RSS that has gained considerable interest in wireless communication systems is to use an intermediate node (relay) which creates a heterogeneous multihop wireless network. In this setup, the AP that connects to the internet is known as the master and has DHCP enabled on it. The user connects to the network via the relay which is known as the slave.

Since the idea is always to maximize the channel capacity in any environment, in this thesis the relay, the master, slave and user are all equipped with MIMO technology which has been proven to increase the channel capacity over the SISO cases.
One of the major drawbacks of MIMO system as shown by research is the effect of correlation between the elements in the array on the channel capacity especially in Line-of-Sight environments. Equipping the relaying node with DAS has also been proposed in this research to address the issue of correlation between antennae elements.

This research intends also to investigate the optimal location of DAS equipped relay that optimizes the downlink channel capacity in a WLAN MIMO line of sight environment. The Genetic Algorithm(GA) is be used to find this optimal location. Another aim of this research is to show that indeed the use of relay whether in the case when the RSS is indicated or not does outperform any traditional AP to user SISO case. The simulation results carried out in these cases reveal that in terms of average channel capacity the Non-RSS-assisted and RSS-assisted cases perform at 28% and 65% respectively better than the conventional user to AP in a SISO case.

關鍵字

MIMO ； WLAN ； Channel Capacity ； Correlation ； Distributed Antenna System(DAS) ； Genetic Algorithm

並列摘要

WLAN networks have become very popular means for providing a wireless networking facility for home users, educational institutions, companies etc. due to their ease of installation, flexibility and their high data rate provision, apart from providing, albeit limited, mobility to users. As the environment under which these WLANs operate greatly influences their performance due to free space path loss, shadowing, multipath propagation, which result in weak received signal strength (RSS) at the receiver, a lot of research has been made to address this issue, that is. One technique to boost the RSS that has gained considerable interest in wireless communication systems is to use an intermediate node (relay) which creates a heterogeneous multihop wireless network. In this setup, the AP that connects to the internet is known as the master and has DHCP enabled on it. The user connects to the network via the relay which is known as the slave.

Since the idea is always to maximize the channel capacity in any environment, in this thesis the relay, the master, slave and user are all equipped with MIMO technology which has been proven to increase the channel capacity over the SISO cases.
One of the major drawbacks of MIMO system as shown by research is the effect of correlation between the elements in the array on the channel capacity especially in Line-of-Sight environments. Equipping the relaying node with DAS has also been proposed in this research to address the issue of correlation between antennae elements.

This research intends also to investigate the optimal location of DAS equipped relay that optimizes the downlink channel capacity in a WLAN MIMO line of sight environment. The Genetic Algorithm(GA) is be used to find this optimal location. Another aim of this research is to show that indeed the use of relay whether in the case when the RSS is indicated or not does outperform any traditional AP to user SISO case. The simulation results carried out in these cases reveal that in terms of average channel capacity the Non-RSS-assisted and RSS-assisted cases perform at 28% and 65% respectively better than the conventional user to AP in a SISO case.

並列關鍵字

MIMO ； WLAN ； Channel Capacity ； Correlation ； Distributed Antenna System(DAS) ； Genetic Algorithm

參考文獻

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