Chip maker Microsemi has announced a new mobile fronthaul product, based on its DIGI-G4 family of Optical Transport Network (OTN) processors, that will enable high-capacity mobile fronthaul connectivity for converged 4G and 5G centralised radio access networks (C-RANs).
The new product, which will be highlighted at OFC 2017, breaks new ground by extending the use of OTN into mobile fronthaul architectures. Unlike conventional WDM approaches that allow for one radio per WDM link, Microsemi’s DIGI-G4 OTN fronthaul processor can aggregate multiple 4G or 5G radios links into 100G OTN connections to deliver up to 10 times the capacity on the same optical infrastructure.
Microsemi’s OTN approach will allow the interconnect between distributed radios and centralised baseband equipment to scale in capacity as mobile technology advances. As mobile operators add new LTE-Advanced features such as carrier aggregation and higher-order MIMO, and densify their networks using small cells, existing 4G fronthaul links will need to scale by a factor of four times to a 10G rate. With the transition to 5G, fronthaul connections will need to scale up to 200Gb/s, driven by dense 25GbE links from 5G radio heads.
“C-RAN is 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 fibre-efficient approach to building fronthaul networks impeded the industry’s transition to C-RAN,” said Babak Samimi, vice president and business unit manager of Microsemi’s communications business unit. “With the ecosystem continuing to cost-optimise 100G optics, in addition to the unique innovations integrated in our DIGI-G4, Microsemi has put forward a compelling answer to the fronthaul 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.”
Microsemi says its DIGI-based mobile fronthaul processor provides future-proof protocol support. It has been designed to provide simultaneous support for CPRI option 5, 6, and 7 for today’s 4G networks, as well as 10GbE, 25GbE, 40GbE and 100GbE protocols required for 5G in the future.
The product is differentiated with an embedded optical link security engine, and integrated patent-pending real-time link latency equalisation. Latency is as low as 8µs microseconds with forward error correction (FEC), with automatic per-link latency management and reporting.
China mobile endorsed the announcement. “Microsemi has been a long-time key enabler for China Mobile to deploy 100G OTN switching in the metro and long haul network,” said Dr. Li Han, deputy director of the network department of China Mobile Research Institute. “We are pleased to see Microsemi extending its OTN leadership to 4G OTN fronthaul and actively prepare for 5G OTN fronthaul by enabling cost-effective, low-latency, high capacity, and future-proof 100G OTN mobile fronthaul in its DIGI family.”
Microsemi’s DIGI-G4 family is in production and can be ordered now for delivery in the summer of 2017.
Additionally, at OFC 2017, experts from Microsemi will present a tutorial titled, “Beyond 100G OTN Interface Standardization” on March 23 at 8am PDT.