Small Cell Wireless Backhaul for Metrocells has attracted a lot of attention in recent months, with vendors launching new products, introducing new technologies and agreeing new sales channels.
We've assembled a fairly comprehensive list of potential suppliers across all wireless technologies, and discuss each briefly in turn. The properties and trade-offs for each type of technology lead to a toolkit approach, using different techniques depending on the deployment scenario as summarised in this article.
NLoS frees metrocell installations to be almost anywhere, working through or around obstructions including large buildings and street furniture. Some in this category might better be termed nLOS (near Line of Sight), where signals can go around but not through obstacles in their path., Although inherently point to multipoint (P-MP), directional antenna may be used at both end-points to improve performance and increase capacity by sectorising the central site. Spectrum may be limited and/or costly, which constrains the maximum data capacity of such solutions.
- Airspan have integrated wireless backhaul into their Metrocell, evolved from their earlier WiMAX TDD radios. It makes for a compact solution. They also market the backhaul unit standalone, named as their iBridge product.
- BLiNQ Networks specialise in this field, claiming performance of 82 Mbps in only 10MHz bandwidth with their latest X-100 product.
- Cambium Networks, formerly part of Motorola, has a wide product range with over 3.5 million access points installed to date. The Canopy range of Point-to-Multipoint are probably the most relevant, with data rates up to 90Mbps per sector, 540Mbps per tower.
- Ceragon, who also offer a wide range of backhaul equipment, specifically target their NLoS (and E-Band) products for small cell backhaul.
- DragonWave launched the Avenue Link Light product in February 2013. Compact and light (<2Kg), it is scalable up to 40MHz TDD bandwidth.
- Fastback Networks are a startup who have just announced their ServiceEdge solution, which achieves 500Mbps and uses Qualcomm's latest chip. They raised a further $15 million round of funding in May 2013.
- Max4G, a Minessota startup from 2008 focussed entirely on 4G metrocell backhaul. Their product claims 520Mbps with sub 1 millisecond latency.
- NEC include NLoS in their overall small cell backhaul portfolio, but the press release is a bit vague about whether this is in-house or resold and exactly which products/capabilities are available.
- RADWIN has years of experience in this field and offers equipment that operates in a wide range of different frequency bands, with selected products suitable for this application.
- Taqua, a US based firm also known for their low cost core network kit, offers their W-Series kit which supports up to four sectors to increase capacity. [Update: Taqua was acquired by Sonus and these products discontinued]
Microwave links have been the mainstay of macrocell wireless backhaul worldwide, leading to a large variety of different microwave equipment suppliers and significant volume and cost advantages. Some, such as Cergaon, actively recommend alternative technologies for small cell backhaul such as NLoS or 60/70/80GHz. Therefore, this section lists those companies who explicitly promote products in this frequency range with a suitable form factor and performance for the "last mile" of Metrocell backhaul.
- Aviat. Global provider of mobile backhaul microwave products, although little marketing specifically for small cells to date. See also their 70/80GHz E-band products.
- Cambridge Broadband Networks: Their VectaStar compact, high performance point-to-multipoint systems have been widely used in Metrocell trials to date. Sector capacity of 300Mbps and low latency, their systems use FDD rather than TDD mode.
- CCS: A new startup based in Cambridge UK, with product announced, capital raised and shortly starting commercial pilot trials. Uses innovative self-organising mesh technology to connect multipoint-to-multipoint nodes, minimising the installation and ongoing maintenance cost.
- DragonWave announced their new AvenueLink product family in February 2013, specifically designed for urban street canyon scenarios. Up to 400Mbps per hop and 1Gbps per aggregation node. NSN also resell this solution.
- Ericsson: The Swedish telecom multi-national, has many years of microwave product heritage. There is little specific small cell/Metrocell marketing material available to determine the suitability of this part of their portfolio.
- Huawei: The Chinese telecom giant includes their own RTN 310 product in this space, which is described with Gigabit throughput with zero footprint.
- Intracom: This Greek system integrator has also developed their own in-house microwave backhaul portfolio, with both P-P and P-MP options.
- NEC: Offer their iPASOLINK AX all-outdoor radio and iPASOLINK split-mount series for remote small cell connectivity and urban aggregation.
- ZTE. Believed to have their own in-house product, but little information available on their website.
This high frequency spectrum has the combined advantages of low (or zero) spectrum cost and high capacity. The relatively short range of up to 1km and the use of narrow point-to-point beams limits interference and enables high frequency reuse. Point-to-point links can achieve data rates in excess of 1Gbps. Read more about 60GHz technology in a separate article.
- BridgeWave. This Santa Clara USA company has a wide portfolio of wireless link products, including microwave in 18-24GHz and E-band 70/80GHz. Its Flex4G products were launched in February 2013 with models offering speeds from 100Mbit to 1Gbit/s.
- DragonWave: Product literature for their AvenueLink product launched in February 2013 indicates this is also available at 60GHz.
- NEC: In February 2013, NEC launched the iPASOLINK SX for urban street-level connectivity. This 60GHz (V-band) compact high-capacity all-outdoor radio is currently being evaluated by 5 major network operators in Europe, scheduled for commercial availability in the second quarter of 2013. No product details are yet published on their website.
- Siklu: This Israeli company launched their 60GHz product, Etherhaul 600, in February 2012. It offers up to 1Gbit/s throughput and claims to be the smallest physical size in the industry, but the company does not publicly reveal these measurements on their website.
- Sub10: This UK based company offers both 60GHz and 70/80GHz millimetre wave point to point solutions. The Liberator series comes in three models, ranging in speeds from 100Mbit/s to 1Gbit/s. The units include a built-in alignment tool for installation. The wireless links are also SyncE and 1588v2 capable for timing/sync support. There prooducts were resold by Alcatel-Lucent as part of their overall metrocell backhaul portfolio. This company was acquired by Fastback Networks in 2015.
- Vubiq: This Californian company offers their HaulPass product with both 60GHz and 5GHz radios, incorporating a motorised auto-alignment mechanism which removes the need to manually align during installation. It is also claimed this helps alleviate vibration and sway issues. Data throughput rates of up to 1.25Gbps line rate full duplex.
Many of the same companies offer products in both 60GHz and 70/80GHz frequencies. The higher 70/80GHz equipment often has a higher range, enjoys even higher data capacities than 60GHz but may require a larger form factor with dish antenna sizes of 30cm or more.
- Aviat: With 50 years in all aspects of the microwave business, this large US vendor offers E-Band links for high capacity LTE cellsites.
- BridgeWave: This US vendor was one of the pioneers of E-Band, winning substantial business from Clearwire to connect many of their WiMAX sites.
- Ceragon: From their comprehensive mobile backhaul portfolio, Ceragon prioritise their NLoS and E-Band products for small cell backhaul.
- Ericsson: The Mini-Link PT6010 provides 1Gbps data throughput over short hops.
- Huawei: Their RTN 380 product launched late 2012 delivers over 2.5Gbps with only 500MHz channel spacing.
- LightPointe: Their AireBeam products include 70/80GHz links for backhaul, featuring low power consumption and low latency.
- NEC: Announced the iPASOLINK EX for urban small cell traffic aggregation and distributed RAN 'fronthaul' delivering capacities in excess of 10Gbps, commercially released February 2013 and preselected for deployment by two major pan-European network operators.
- Siklu: Their EtherHaul 1200T and 1200F products, operating in TDD and FDD modes respectively, are some of the most widely deployed E-Band products today. Uses their in-house RF silicon-germanium chipset., achieving 1 Gbps data rates.
Free Space Optical and other alternatives
I've seen several companies offering free space optical links with data rates up to 1Gbps or more. Spectrum is free. I've only seen one vendor actively marketing their solution for small cell backhaul, although LightPointe also has product that might be suitable.
- Polewall: This Norwegian startup has pioneered some remarkably low cost product capable of 1Gbps or more.
Another possible option comes from E-Blink. This French company have designed point-to-point links operating in the unlicenced 2.4GHz and 5GHz Wi-Fi spectrum that can achieve multi-Gigabit data rates. These are primarily designed to support remote radio units, rather than just small cells, using the CPRI or OBSAI standard interfaces and is marketed as a "fronthaul" solution.
And last but not least, Wi-Fi has a place for small cell backhaul, although some might limit its use for tactical or fallback scenarios because it operates in unlicenced and uncontrolled spectrum. Ruckus Wireless is a leader in public Wi-Fi solutions and their products have already been used for backhaul, for example between street light-poles.
While we have tried to include all those vendors actively promoting a small cell wireless baclhaul solution, we offer no recommendation or analysis as to the relative fitness for purpose, commercial availability or cost of these solutions. Nor should readers expect this list to be complete.
What is clear however, is that the market for small cell wireless backhaul – predicted to exceed $1.5 Billion annually by 2016 – is attracting a wide range of competitive vendors.
If you feel that any company has been omitted or mis-represented above, please comment below or Contact Us so that any discrepancies can be rectified.