Bandwidth saving in Xhaul network architecture with CPRI line bit rate reconfiguration

Cloud Radio Access Network (C-RAN) or centralized RAN could be seen as a promising solution to deal the 5G requirements. Traditional C-RANs are organized as a three-element network, that contains Base Band Unit (BBU) pool, Radio Radio Remote Unit (RRU) and the network interconnecting BBUs and RRUs called fronthaul. The BBU provides baseband signal processing functions and the RRU provides Radio Frequency signal transmission and reception functions. In this paper we propose procedures for the dimensioning of the transport network resources in the following scenario: i) all of the physical layer functions are implemented in the BBU and the signal samples are transported on Common Public Radio Interface (CPRI) flows; ii) Ethernet traffic is also transported for the use of traditional Radio Base Stations (RBS); iii) bandwidth saving techniques are applied by means of a reconfiguration of CPRI line bit rate so as to reduce the number of circuits of the transport network in the low traffic scenario. We show how the application of the introduced techniques allows for a saving of bandwidth in the order of 80%.