Summary: | 碩士 === 國立中山大學 === 電機工程學系研究所 === 104 === In this thesis, we propose a small-cell embedded large-cell sectored network (SELSN) architecture. An SELSN can be divided into two regions, the sector and the small cell. We increase the total number of overall system channels by using fractional frequency reuse (FFR), and divide the bandwidth into two or three sections depending on whether the number of sectors is even or odd. In order to analyze the new-call (NC) blocking and handoff-call (HC) dropping probability of the proposed SELSN, we build a mathematical model of Markov chains. In the mathematical model, we derive the handoff rate from HC by the area and the boundary length where a mobile station (MS) stays, and the speed and the direction of an MS. Based on the handoff rate of HC, we derive the Markov chain’s transition matrix to obtain the probability of each state. Finally, we change the size of a small cell’s radius, the number of the sectors, and the speed of MS to analyze the NC blocking and the HC dropping probability. From the two probabilities, we obtain the average waiting time (AWT) of an MS and the throughput of the overall system.
|