Abstract ▼ AI-Helper

Microcellular systems provide a means of increasing system capacity due to channel reuse efficiency. Diamond-shaped urban microcells using an omni-directional antenna have been proposed in several measurement-based radio propagation studies. However, few analytical approaches on these microcells hav...

Microcellular systems provide a means of increasing system capacity due to channel reuse efficiency. Diamond-shaped urban microcells using an omni-directional antenna have been proposed in several measurement-based radio propagation studies. However, few analytical approaches on these microcells have been attempted because of complexity. These microcells suffer a large radio signal attenuation in the Non-Line-Of-Sight(NLOS) region. In this thesis a new diamond-shaped urban microcell using distributed/directional antennas and a shared channel allocation scheme is proposed in order to improve radio signal quality and system capacity. The proposed microcell is analytically compared with conventional microcells in terms of input/output rates, dwelling/channel holding time distributions and service rates. Dwelling and channel holding time distributions in the microcell are analyzed characterizing user mobility and handoff traffic. Finally, the performance of conventional and the newly proposed microcellular systems is evaluated in terms of call blocking probability and forced termination probability. The result shows that the newly proposed microcellular system yields larger system capacity. The result of this study can be utilized in the implementation of urban microcellular systems.

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