Microsemi Corporation has announced a new mobile front-haul solution, built on its DIGI-G4 family of Optical Transport Network (OTN) processors that will enable high capacity front-haul connectivity for 4G and 5G centralized radio access networks (C-RANs). The solution, which was highlighted at The Optical Networking and Communication Conference & Exhibition (OFC) 2017, breaks new ground by extending 100G OTN into the RAN to simultaneously aggregate high density Common Public Radio Interface (CPRI), 10GE and 25GE radio links. It also enables a 10 times increase in capacity, while introducing innovations to address the need for low latency with automatic link equalization, and network security.
Mobile operators worldwide are evolving their RANs from a distributed to a centralized base station (C-RAN) model as a means to cost-effectively grow mobile capacity and prepare for 5G. According to market research firm IHS, C-RAN deployments will grow at 23 percent annually through 2020, representing greater than 60 percent of all 4G RAN deployments in that timeframe.
As mobile operators continue to add new LTE-Advanced (LTE-A) features such as carrier aggregation and higher order MIMO, and densify with small cells over their existing 4G networks, the CPRI interconnect between distributed radios and centralized baseband needs to scale by a factor of four times to a 10G rate. With the transition to 5G, front-haul connections will need to scale up to 200 Gbps, driven by dense 25GE Ethernet links from 5G radio heads.
C-RAN is now becoming the go-to network architecture as mobile operators address the need for increased capacity, but until now the lack of a cost-effective and fiber-efficient approach to building front-haul networks impeded the industry's transition to C-RAN. With the ecosystem continuing to cost-optimize 100G optics, in addition to the unique innovations integrated in DIGI-G4, Microsemi has put forward a compelling answer to the front-haul networking challenge that not only delivers on the significant increase in optical capacity needed, but allows operators to drive C-RAN deployments anchored on a unified architecture that allows for a seamless transition from 4G to 5G.
Unlike conventional wavelength-division multiplexing (WDM) solutions that allow for one-radio per WDM link, Microsemi's DIGI-G4 OTN front-haul architecture allows for the aggregation of multiple 4G or 5G radios links into 100G OTN connections which deliver up to 10 times the capacity scaling over existing optical infrastructure. Differentiated with an embedded optical link security engine, integrated patent-pending real-time link latency equalization and simultaneous support for 4G CPRI and 5G Ethernet protocols, Microsemi is helping redefine the capital expenditures (CAPEX) and operating expenses (OPEX) cost of ownership paradigm in building front-haul networks for mobile operators.
Microsemi's DIGI-based mobile front-haul solution delivers a number of unique innovations, including:
Extending 100G OTN and enabling link security into front-haul
- Simultaneous aggregation of 4G and 5G radios into 100G links eliminates need for WDM optics
- Embedded optical security engine to secure links connecting radios to baseband
Future-proof radio protocol support
- 4G protocols: CPRI option 5, 6, and 7
- 5G protocols: 10GE, 25GE, 40GE and 100GE
High performance front-haul networking
- Latency: as low as 8µs microseconds with forward error correction (FEC)
- Up to 75 percent margin to CPRI jitter spec
- Latency equalization to within nanoseconds
Patent-pending automatic per link latency management and equalization
- Per CPRI latency measurement and reporting
- Automatic uplink and downlink latency equalization
- Latency compensation for working and protect paths
The DIGI-G4 family is now in production and will be available in the summer of 2017.
