WCDMA downlink capacity of cigar-shaped microcells for underground metro service

In this paper, the wideband code division multiple access (WCDMA) downlink capacity and the interference statistics of underground cigar-shaped microcells utilised to serve users within metros are analysed. The hybrid model of propagation is used in the analysis where a model of eight cigar-shaped microcells is used. The downlink capacity is given for different sector radio R, train length Ltrain, break point distance Rb and propagation parameters (s and γ). It is found that increasing the sector range up to 1250 m will increase the sector downlink capacity. Also, it is found that the effect of changing the value of the propagation parameter s is very small. It is noticed that increasing the train length Ltrain will increase the downlink capacity. Also, it is noticed that, increasing the propagation parameter γ will reduce the sector downlink. Finally, it is found that, the effect of changing the break point distance Rb is quasi-null. Copyright © 2008 John Wiley & Sons, Ltd.

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