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December 2008

‘VectaPower’ the greener option for backhaul

Lance Hiley, VP Market Strategy, Cambridge Broadband Networks, discusses why PMP is the greener option for backhaul

Lance Hiley

The arrival of the recent Unstrung Insider report “Mobile’s Green Challenge” got me thinking about what the microwave backhaul community can do about reducing the amount of electrical power it takes to run a backhaul network.

We like to think that we are pretty good at pointing out the benefits of microwave point-to-multipoint architecture here at Cambridge Broadband Networks, but it became clear reading the Unstrung report that the benefits of using PMP to reduce power consumption are considerable as well! The way I see it, PMP and especially the way we implement it in VectaStar, is capable of making significant impact into reducing the power consumed in the backhaul network.

The first benefit should be obvious: PMP backhaul networks have nearly half the number of radios compared to point-to-point solutions and as such, consume nearly half as much electrical power. This varies, of course, depending on which PTP microwave solution you may choose to make a comparison with, but the reduction is still significant. As we move into 2009, in the face of the mobile backhaul explosion, operators planning how to densify their networks would be well advised to add ‘power consumption reduction’ to the list of criteria as they consider microwave backhaul systems.

The second benefit is not so obvious: VectaStar is, and always has been, a remote radio head technology. The baseband and radio is integrated into a single, mast-mounted unit that does not require specialised air-conditioning in the hut to maintain the radio at operating temperature. Long RF cable runs from the hut to the antenna require high levels of power. VectaStar, with its integrated terminal and slip-fit antenna-mount technology, eliminates long cable runs and speeds up installation time. Furthermore, VectaStar has been installed in locations as cold as Finland and Siberia as well as the heat of the Middle East so operating temperature range is not an issue either!

The third benefit is more obscure still. If you took-up the offer from my colleague Deyan Boyich in the last edition of Infocast to learn more about the 2009 VectaStar roadmap, you will know that we have considerably more capacity and bandwidth coming to VectaStar very soon. This additional performance – tripling the capacity – comes with little increase in power consumption, thanks to the proprietary ASIC technology developed by and exclusive to Cambridge Broadband Networks’ VectaStar.

So, there you have it: half the power conception, remote radio head and significantly more capacity. It certainly seems like VectaStar should be high on the list of any transmission planner trying to reduce power consumption!

Lance Hiley – VP Market Strategy

Lessons the world can learn from Africa

Neeren Ramharakh, VP Sales – Sub-Saharan Africa, Cambridge Broadband Networks, explores why Africa is better prepared for 4G

African operators are arguably better prepared for 4G than many of their counterparts in developed markets. Crucial to this is the fact that they are solving the key issue of backhauling the high volumes of data associated with technologies such as HSPA, WiMAX and LTE – and doing so cost effectively.

Panel showing the areas of Africa that have deployed VectaStar

The adoption of point-to-multipoint in Africa has given operators full control of their backhaul networks and control of the costs associated. It is a proven technology that has already demonstrated that it’s ‘4G ready’ – it currently powers the backhaul networks of several WiMAX operators in the region. Contrast that with the launch of Sprint’s Xohm WiMAX network in the US, which was delayed for several months principally because the backhaul network was not felt to be robust enough.

Through a liberal dose of innovation driven by necessity, African operators have successfully overcome the fundamental backhaul issues being faced by their counterparts in the developed markets. It may now be time for the developed markets to learn from the African experience.

An African Success Story

Mobile is truly an African success story. Now out-stripping landline connections by a factor of eight, the mobile subscriber base has grown to 282 million, an increase of 30 percent in the 12 months to May 2008. Furthermore, mobile broadband services in the region are on target to outstrip the fixed line alternatives. According to AfricaNext Investment Research, mobile broadband will account for more than half of the continent’s broadband subscriber base by 2012, more than a four-fold increase. Perhaps most telling of all is analyst firm Informa Telecoms and Media’s prediction that African mobile data traffic will grow from 33.11 Petabytes (PB) in 2008 to 94.21 PB in 2012 – an astonishing compound annual growth rate of 23.3 percent.

While much of this growth is due to a lack of fixed line infrastructure, African mobile consumers are also replicating the behavioural trends seen in other parts of the globe. In South Africa for instance, demand for mobile content is expected to grow by an average of 15 per cent per year during 2008–2013 according to Frost and Sullivan. The forecast growth is attributed to rising customer awareness of the wide range of content-based services and applications available, and the added functionality those applications and services provide. Instead of simply downloading, users are now creating content themselves and sharing it amongst their friends and colleagues.

Yet there is another crucial dynamic behind the upward trend. Unlike the developed world, much of the growth in data traffic has been driven by the small medium enterprise (SME) sector for access to essential business services such as email and web browsing. In a continent where fixed line connections are either unavailable, unreliable or expensive, mobile operators have been able to steal a march on their fixed line competitors by offering fast, reliable and cost-effective connectivity to the mass market.

Operator challenges

This success story brings with it significant challenges for operators in the region.

The performance of any cellular network, particularly where data is concerned, is only as good as its ability to backhaul voice and data traffic from its base stations and into the core network. It doesn’t matter how the radio access network performs, if backhaul capacity isn’t available, end users will be presented with a degraded service and disappointing data transfer rates. Providing optimal backhaul capacity comes at a significant cost – estimated at around 30 percent of a typical operators’ annual capital and operational expenditure. And this expense becomes harder to justify when average revenues per user (ARPU) are relatively low.

In Africa this can vary from as much as $11.25 in South Africa to $5.31 in the Democratic Republic of Congo and $2.61 in Mozambique.

This puts African operators at an obvious disadvantage compared to those in developed markets such as Europe and North America where ARPU – to take Verizon in the US as an example – can be as high as $53.9. African operators have limited room for manoeuvre when it comes to costs relative to their counterparts in ‘the west’. Carriers in the region simply cannot afford to over spend on the provision of backhaul. African carriers also have fewer alternatives for backhaul provision. The lack of fixed line infrastructure, as much as it has benefited their business in terms of subscriber growth, has severely restricted their backhaul options. The fibre and E1/T1 leased lines in use in many markets simply aren’t available in many African countries. This means that operators in the region have had to get smart when it comes to backhaul and has largely led them to opt for a microwave solution.

A blessing in disguise?

The lack of fixed line infrastructure may have first been seen as a severe restriction but in many ways it has benefited operators in Africa. By choosing microwave, and in particular point-to-multipoint microwave, operators have been spared the prohibitive cost of digging hundreds of kilometres of tunnelling to lay fibre optic cable. In turn their customers haven’t been inconvenienced by associated road works as a result of the construction.

Even more importantly, carriers have been able to achieve fibre-like connectivity speeds whilst owning and controlling their own backhaul network. This has meant some operators are able to operate their backhaul infrastructure with half of the operating expenditure of their counterparts using more traditional options.

As African markets become more competitive operators have limited room to manoeuvre on voice pricing. The challenge for operators is to build their networks quickly and cost-effectively so they can introduce additional features based on data and improve coverage range and service quality. Point-to-multipoint aids the process by supporting voice and data on a single platform and dramatically reducing the time it takes to build the network – up to 50% less than a comparable point-to-point architecture.

Point-to-point versus point-to-multipoint backhaul

As has been indicated, there are two flavours of microwave backhaul: point-to-point, and point-to-multipoint. Traditionally mobile networks have been designed using the ‘fat pipe’ point-to-point (PTP) approach, where the links operate at a fixed frequency and capacity, and operators have to design the network to provision for peak loads. PTP is best suited to rural areas and longer range or short very high capacity links. Generally a spectrum license for each link is required and that link can only carry one type of traffic over one frequency.

Provisioning for peak loads means that PTP links operate at well below maximum capacity most of the time. Additionally, some frequencies are affected by atmospheric conditions, requiring a step-down in capacity for a short period of time whilst an atmospheric event – like a rain storm – passes. The overall effect is that individual PTP links may be operating at only 10 percent capacity most of the time, a highly inefficient model and a poor use of valuable spectrum resources.

Point-to-multipoint (PMP) microwave, by contrast, uses a different and dynamic architecture to address the backhaul issue. Rather than fixed links, PMP brings a number of cell-site links back to a single aggregation point or hub. Immediately, this reduces the number of radios and antennae making the network less expensive to build, as well as energy efficient. In addition, because the spectrum for the system is licensed across a number of radios, the resource is in effect shared – making the utilisation of the spectrum more efficient and more flexible. PMP microwave systems also lend themselves to a more IP-like approach to packet data management.

Working with a base raw data rate of over 150Mbps gross throughput, PMP backhaul architectures then apply data optimisation and statistical multiplexing to provide an ‘efficiency gain factor’ of up to x5. This effectively upgrades the capacity of a comparable PMP solution to backhaul 700Mb/s or more per sector – sufficient for the onset of ‘4G’ technology such as WiMAX and LTE. Not only is PMP easier to deploy than other backhaul technologies, it also offers increased capacity at a much lower ‘cost per bit’. For a typical African operator the cost savings can amount to 50 percent compared with traditional microwave solutions.

As a result of these capabilities, Cambridge Broadband Networks estimates that market for this technology will grow from $115M per annum in 2008 to $442M in 2012.

Point-to-multipoint as an access technology

Operators in Africa are also benefiting from the fact that point-to-multipoint can be used as an enterprise access technology. With the ability to connect multiple sites from one point-to-multipoint hub (as well as simultaneously backhauling macro cellular traffic) this gives operators a valuable additional revenue stream since they can charge for specialist enterprise access. This sector is currently growing very rapidly – it offers businesses an ‘always on’, highly resilient internet and data connection.

Breaking with tradition

Although point-to-multipoint has been deployed for cellular backhaul in western markets, it has not been embraced with the same enthusiasm shown by African operators where, in some cases, it comprises more than 30% of their backhaul network. While the western operators do have to deal with legacy issues, they might be able to learn a trick or two from their African counterparts who have broken with tradition and deployed new architectures and technologies that will support them in the years to come.

Neeren Ramharakh, VP Sales – Sub-Saharan Africa

Download in this article as a PDF.

Previous editions of Infocast

Microwave Applications Workshops 2009

Cambridge Broadband Networks Microwave Applications Workshops 2009

Cambridge Broadband Networks is launching a series of Microwave Applications Workshops to run throughout 2009. These workshops will give our customers the opportunity to learn about VectaStar in an interactive environment, network with key players in the MNO marketplace and discuss the future of backhaul network strategies.

The workshops will cover

  • Strategic positioning of carrier-grade PMP microwave solutions
  • VectaStar product introduction
  • Application-based business case
  • Operator case studies
  • VectaStar roadmap
  • Planning and deployment considerations

And the
winner is …

Nikoly Evtuhov's winning picture of a VectaStar equipement deployment

… Nikoly Evtuhov from ATEMS.

His iPod Touch is on its way!

Thank you to everyone who sent in their photographs of VectaStar in deployment.

We’ll be running more competitions like this in 2009.


Mobile World Congress
16 – 19 February 2009, Fira Montjuïc, Barcelona
Business hospitality suite 4.3HS30
If you’d like to book a meeting with us at the event, please email

Did you know?

Screenshot from the VNMS

Cambridge Broadband Networks launched the VectaStar Network Management System in November 2008

The VNMS provides a graphical environment for operators and service providers to configure, manage and monitor their VectaStar network.

Deyan Boyich, VP Product and Services explains:

VectaStar is now deployed in more than 150 networks in 33 countries worldwide – and growing. This represents an ecosystem worth more than $0.25 billion. With this scale, we recognised the need to take VectaStar network management to the next level. Many of our customers are now deploying VectaStar in increasingly complex networks and need to configure and monitor much larger networks in greater detail and in real time. The VNMS will enable them to do this and provide them with a wide range of customisable reports, statistics and graphs enabling them to identify trends and better plan their backhaul networks.

Read more » in our press release.