No abstract

No abstract

A techno--economic analysis of the 5G eMBB (enhanced Mobile BroadBand) scenario in dense urban areas has been accomplished by radio capacity modelling of probable 5G technologies within a 1km 2 grid representing central London.Different density networks were modelled at: 700MHz (macro network), 3.5GHz (micro network) and 24--27.5 GHz(hot spots) -together with 802.11ac access points. Using published data on network costs various deployment options have been evaluated for capacity, headline rate and CAPEX/OPEX. It has been shown that reaching headline rates of 64--100Mbps everywhere is possible with a number of different technology options. Massive increases in capacity (in excess of 100Gbps/km 2 ), however, can only be realistically achieved with millimetre wave (outdoor) and WLAN (internally). The cost of deploying such capacity, however, will be several times that of LTE -we estimate a 4 to 5 times increase in costs for a 100Mbps everywhere network that has x100 capacity increase over existing LTE networks. The cost of rolling out 5G is becoming an important issue and this work provides one of the few published estimates of the economics of ultra--high capacity networks.

Interference alignment (IA) has been demonstrated to achieve the degree-of-freedom (DoF) of an interference channel given perfect global channel state information (CSI). In this letter, we consider the case of imperfect CSI with bounded errors and derive a capacity lower bound of the channel using IA. We show that this lower bound is within 1 bps/Hz of the capacity of the perfect CSI case up to a certain signal-to-noise ratio (SNR) which we refer to it as the saturating SNR. Further, we introduce a new metric called modified DoF (mDoF) in order to characterize the multiplexing performance of IA with imperfect CSI at finite SNR. Simulation results for the 3-user case are provided to illustrate the region within which the actual capacity of IA falls.

No abstract