Magic boxes, amazing toolkits and long haul tails empowering small cells backhauling

By Elias Aravantinos

Cost effective solutions and future radios planning in respect to NGMN guidelines and not only were discussed during the 2-days event of Packet Microwave and Backhaul Forum organized in London by Layer 123. Backhaul remains a commercial and technical challenge, where many intelligent solutions could be provided reserving simplicity as Everything Everywhere (EE) highlighted. Operators and vendors had the chance to exchange concerns, identify issues and solutions to push mobile backhaul and small cells further down the road. All technologies were discussed and debated, from Point-to-Point (PtP) and Point-to-multipoint (PmP) to NLOS (Non-Line-of-sight) and high performance V-band and E-band solutions. The products exhibition helped the attendees to get a better idea of form factors, size and feel but also look into some demo data as presented from the big microwave players such as Alcatel-Lucent and NEC. Even North American vendors were actively participating such as Bridgewave and Aviat Networks.

Huawei presented its brand new E-Band solution, expected to be launched even earlier this year, a full outdoor radio performing a throughput of up to 2.5 Gbps, (over 250 MHz channels), which will be further improved to a fiber-like capacity of 10 Gbps or higher. It is ideal to support ‘pipe’ channel or similar capacity demanded situations. It attracted lots of attention and expected to have an impact to the industry till the upcoming WMC in February 2013. 

Other vendors, exhibited also their millimeter wave radios, such as Sub10, SIAE and Siklu. Traditional PMP vendors, Cambridge Broadband Networks and Intracom Telecom presented also small cells solutions, with the latter getting some more attention on the new concept, the ‘WiBAS metro node’ solution for small cells backhauling introducing a single piece of equipment for a single band. Perhaps some joint force is needed to prove the PmP business case, because just the ‘less equipment’ argument might not be enough anymore from an industry’s voice perspective. Big vendors like Alcatel Lucent continue to examine the PmP technology investigating other vendors’ solutions, looking into partnerships as in the past they did with CBNL for a customer’s request. This time though is looking more intensively into Radwin’s radios that seem to have a better fit and a partnership could be possible along pre-defined terms.

Along news concepts was also CommScope, a well-respected antenna producer (300,000 units per year) holding more than 50% of backhaul traffic, thinking beyond class 4 antennas – which allows better use of ACM - to flat antennas, could even called class 5 that could gain more than 84% in efficiency within a cost of a couple of hundreds of dollars. Bluwan as always was there discussing millimeter wave PMP with their brand new CTO but also BlinQ Networks discussing sub 6 GHz NLOS solutions and a comparison TCO case study, expecting to play a key role in the toolkit approach. However although these two companies have completed a series of trials, there is still no proof, case studies or articles on discussing the results in an either technical or business approach.

Thus all these small factors magic boxes, with all this continuous reengineering and strict guidelines and performances are looking for some light in the end of the tunnel, revenues, when today the mall cells volume still remains in a few thousands level . High density areas will expect to form ecosystems hosting a toolklit approach, where several technologies could co-exist (i.e PmP and 60GHz etc) in order to achieve the best performance and cost effective sites. QoS, QoE, capacity and coverage could definitely be the drivers to that. Additionally, the new innovative services, M2M and cloud might also ask for high performance networks.

A few cases studies were presented trying to coin the small cell economics with some cost and ratio analysis between the macro and microcell level.  A 1:11 or 1:5 ratio could be possibly a good guess, in a macro-to-micro ratio, with the small cells in the near future to follow a 10-20% of the macrocells’ cost, as EE mentioned. The small cells locations would need additional planning to capture as much traffic as they can. Definitely, anyone could argue with these numbers but we are still in the early stages of small cells backhauling and deployment, expected to pick up by mid-2014. The big argument is that if the macrocells are 25% utilized, how much will be the small cells? If we take as an example the city of London, tons of people go in and out the city daily for work. In that sense, traffic will appear in bursts, where the small cells radios might remain idle overnight. That’s a good reason to make the operators align only into low cost solutions for small cells, satisfying certain peaks during the day.

Long haul solutions are also of high interest, especially the effort to migrate whole networks first to SDH and later to packet traffic. Ceragon, the microwave specialist, is digging “Terabit on the beach”, in Africa, mentioning that long haul networks could offer reduced TCO and spectral efficiency. However long haul is not the major operators concern these days, but in a recent microwave applications survey, short haul was is the top (90%) and PmP in the bottom (20%) of the list.

Some issues that still need to be clarified are: what is packet microwave for millimeter wave, for small cells and what are the differences and concerns. Small cells definition given, “low power cells (0.5 – 5W) within an urban clutter”, but is that enough? What are the installation economics and engineering of the site, where and how does ‘the man with the ladder’ fit in and the repeatable process of deploying 20 small cells along a street in a couple of hours or even in a few days as MLL, a UK network operator mentioned. On the other hand it’s difficult to forecast IP traffic due to its large fluctuation, thus robust bandwidth provisioning is needed.

Automated solutions seemed to start shaping a new landscape, as ‘zero touch’ provisioning for scalable rollout, mobility management, SON and overall future intelligent backhaul level developments of stand-alone systems.  Advanced LTE could even change and improve any phase synchronization issues. Looking more into the future, even a 3^rd generation millimeter wave platform could address all the current TCO issues, satisfying all the technical requirements of small cells.

ExelixisNet.com, an independent analyst’s firm, covered the media part of the event, joining interesting discussions with vendors, operators and other analysts, identifying the need for ‘toolkit’ case studies for different cities that could be done either internally and more intensively like the one that EE is working on or externally with a three-part collaboration, operator, vendor and analyst.