Modeling the Effect of Bandwidth Allocation on Network Performance
In this paper, a new channel capacity model for interferencelimited systems was obtained by transforming the Shannon-Hartley theorem for channel capacity. To emulate an operational system, a dashboard Motorola monitoring device was used to collect data from a group of Base Stations (BSs) serving (a section of) the Nigerian air space and belonging to one of the existing network carriers. Our findings revealed that the uplink and downlink throughputs of the existing system were not impressive even when there was uniform sharing of bottlenecks across the BSs. Using MATLAB, simulations were then performed by extending these data, subject to ideal environmental constraints. Results obtained revealed the following: (i) The Shannon-Hartley model performed as expected for no-interference systems (TDMA and FDMA), but as the bandwidth improved, only limited number of users could access the network in the presence of increased SNR; (ii) The proposed model showed improved performance for CDMA networks, but further increase in the bandwidth did not benefit the network; (iii) A reliability measure such as the spectral efficiency is therefore useful to redeem the limitation in (ii).
Keywords: Coverage Capacity, CDMA, Mobile Network, Network Throughput