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| Author: | Zhao, Yue |
| Title: | Analysis of Energy Efficiency in IEEE 802.11ah |
| Publication type: | Master's thesis |
| Publication year: | 2015 |
| Pages: | viii + 50 Language: eng |
| Department/School: | Sähkötekniikan korkeakoulu |
| Main subject: | Radio Communications (S3019) |
| Supervisor: | Tirkkonen, Olav |
| Instructor: | Yilmaz, Osman |
| Electronic version URL: | http://urn.fi/URN:NBN:fi:aalto-201506303486 |
| Location: | P1 Ark Aalto 2956 | Archive |
| Keywords: | IEEE 802.11ah energy efficiency M2M IoTs |
| Abstract (eng): | Recently, machine to machine (M2M) communication has been considerably evolved and occupied a large proportion of the wireless markets. The distinct feature of M2M applications brings new challenges to the design of the wireless systems. In order to increase the competence for M2M markets, several enhancements have been proposed accordingly in different wireless technologies. The thesis introduces these M2M enhancements with a focus on the Wi-Fi solution - 802.11ah technology. 802.11ah is a new amendment of Wi-Fi technology for M2M applications. In 802.11ah, a new mechanism named TIM segmentation has been introduced to provide scalable operation for a large number of devices as well as reduce the energy consumption. The scope of the thesis is to evaluate the energy efficiency of TIM segmentation in uplink traffic assuming Poisson process. To thoughtfully understand the principle of this mechanism, the fundamental MAC layer functions in Wi-Fi technologies have also been introduced. In addition, the thesis also proposed an energy-saving solution called additional sleeping (AS) cycles. The performance evaluation is based on a Matlab system-level simulator. The simulations are carried out for various TIM segmentation deployments for a selected M2M use case, the agriculture scenario. The results show that the TIM segmentation can deteriorate the performance for uplink transmission. This is because that in sporadic traffic, restricting the uplink access causes the increase in packet buffering and these packets leads to simultaneous transmission. This can be a serious issue especially for the network with a large number of devices. The random backoff procedure in Wi-Fi cannot efficiently solve this collision problem. In addition, results shows that the AS cycles can reduce the energy consumption in busy-channel sensing and also decrease the collision probability by adding extra randomness. |
| ED: | 2015-08-16 |
INSSI record number: 51895
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