C-RAN is a centralised, cloud based new cellular network architecture that can be adopted by telecom operators to improve their quality of service with reduced capital expenditures (CAPEX), operating expenditure (OPEX), and energy consumption. ASTRI is developing a flexible and high system performance C-RAN solution to fulfil demanding industrial requirements.


Flexible C-RAN architecture

ASTRI’s C-RAN architecture is based on standard FAPI PS-PHY interface, which can easily integrate with commercial PS software. FAPI is a standard interface proposed by Small Cell Forum, which was adopted by most of the commercially available PS and PHY solutions for LTE/LTE-A base stations. Tasks partitioning for the server and remote units in C-RAN determines the trade-off between enhancing centralised coordination and reducing front haul throughput. ASTRI modular PHY processing architecture provides the flexibility to adopt different partitioning requirements depending on the deployment scenarios.


Multi-cell coordination

Our C-RAN provides new centralised baseband processing capability that realises advanced multi-cell coordinated algorithm. The algorithms, such as Coordinated Multipoint (CoMP), Inter-Cell-Interference (ICI) mitigation, and Active Antenna System (AAS) beam-selection, reduce inter-cell-interference and enhance spectral reuse with small cell size and heterogeneous networks deployment topologies. This has significantly increased the average system spectral efficiency.


Server side load balancing

Centralised processing units in C-RAN enables dynamic computational resources allocation. The processing entities for each cell are dynamically grouped and allocated to server side processors. During low traffic period, the system can shut down the redundant processors or switch the processing power to support other applications. This reduces energy consumptions and increases hardware utilisation of the computation units.


ASTRI C-RAN specifications

FeaturesC-RAN PHY
Standard3GPP release 10
Bandwidth5 , 10, 15, 20 MHz
DuplexingFDD, TDD (All UL-DL configuration and special sub-frame configuration)
# of users256 users per sector
16 UEs/TTI
Cell SizeUp to 10 km
MobilityUp to 160 km/h
Throughput DL: 300Mbps per sector
UL: 150Mbps per sector
UE support Category 1 to 6
SynchronizationGPS, 1588v2
Advanced featuresCA
4x4 MIMO
Beam-forming (TM7 and TM8)