Cost/Revenue Trade-Off of Small Cell Networks in the Millimetre Wavebands

摘要

In this work, we identify and discuss the potentialities of mobile cellular communications in the millimetre wavebands, showing that very high bit/data rates can be supported in small cells with short-range coverage. We study the behaviour of the carrier-to-noise-plus-interference ratio with the coverage distance (and the actual distance from users to the eNBs) in actual environments and the respective analysis of the impact in cellular planning and optimization process. We assess the equivalent supported throughput within cells with reuse pattern K=2, assuming, in this preliminary phase, the use of LTE. In terms of cell coverage and the computation of interference, LoS propagation models have been considered at the 28, 38, 60 and 73 GHz frequency bands. From these analytical computations, we conclude that, at 28 GHz, although lower system capacity is achieved for very short coverage distances of the order of 25 m, in comparison to the 73 GHz frequency band, there is an enhancement in the supported throughput for longer coverage ranges, and it is clearly more favourable for the lowest frequency band. Owing to the additional attenuation of oxygen, the 60 GHz frequency band is more challenging, as the lowest values of the co-channel interference due to the additional oxygen attenuation originate higher values for the supported throughput, even for lower values of the reuse pattern. Based on these results, costs and revenues are studied. Revenues are proportional to the supported throughput and the profit is generally a declining function with cell radii. The highest profit corresponds to the shortest cell radii, up to 80 m, and the best results occur for the 28 GHz band.