Fixed wireless access and Wi-Fi on the move

11 May 2021

Wherever you live, the average broadband speed requirement continues to rise and fibre access is arguably still the go-to option. It makes complete sense, when one considers its high bandwidth performance, low latency and maintenance, as well as durability.

Of course, copper and fibre deployment for better broadband service is not always an upgrade option. Reasons include the fact that municipal regulations can make fibre trenching prohibitive, lower population densities in rural markets often harm the fibre business case return on investment (ROI), while buildings or things of natural beauty may prevent the installation of fibre regardless of how much money has been made available.

That said, fibre is not always available, either, which means other technologies and methods of communication have to fill the void. Enter fixed wireless access (FWA), which is known to offer high-capacity solutions for parts of southern Asia, indeed the world, in need of enhanced quality and speeds. Now, in early 2021, as the dust begins to settle following the worst pandemic any of us will (hopefully) ever have to endure, the demands for speedy internet access on the move is becoming more important than ever before. Does FWA really offer the best way to meet the last mile challenge that wired networks have been unable to solve? If so, how?

“FWA has several major benefits when compared to fixed line/fibre deployments,” says David Sumi, VP of marketing at wireless gigabit solution provider Siklu. “Especially in a large area such as southern Asia where many communities are spread out.  Fixed line deployments are almost always more expensive than FWA and take months to install versus FWA which can be up and running in weeks. It used to be that FWA was at a speed disadvantage to wireline, but with mmWave systems delivering up to 10Gbps full duplex, this is no longer the case. For regions that lack existing wireline infrastructure FWA is cheaper and faster.”

Large swathes of southern Asia certainly lack the infrastructure Sumi mentions, which is unsurprising when one considers the topography across the bottom half of the world’s largest continent by land mass.

The good news is “FWA is generally lower cost to deploy than wired networks such as fibre optic cable”, especially outside of rural areas where the distances between buildings increase, making the cost of laying fibre higher, says William Webb, chief technology officer (CTO) at Cambridge Broadband Networks Group (CBNG). “Where broadband is not available due to cost then FWA can provide an excellent solution,” he continues. “However, even with FWA there will be some regions so remote that only with government funding will it be economically viable to connect them.”

For Simon Fletcher, CTO at independent advisory Real Wireless, FWA  “has  to be a part of the solution” along with options such as satellite that must also be considered. “However if tower infrastructure along with power and backhaul (which could be shared) are well placed, then FWA would give a good, scalable and robust capability for delivering the high per-user data rates that will inevitably be required and demanded by consumers and enterprises alike,” he adds.

Eugina Jordan, VP, marketing at OpenRAN software firm Parallel Wireless, also explains how the cost of legacy high-speed broadband service through cable or fibre-to-the-x (FTTx) deployment, is a significant part of initial network deployment. “The average cost of laying fibre is US$15,000 per mile,” she says. “Also, in many areas the permits for related construction work will take months. This will be a huge burden for service providers because of initial costs that will not necessarily convert into revenue.” However, Jordan says, a fixed wireless solution deployment “is simply based on a base station deployment” and no last mile delivery investment. “In this scenario, service providers will cover specific geographical areas and target customers without any specific investment for last mile delivery for that specific customer. “For rural area deployment; with lower population density, a cable or fibre solution will be even more costly and their ROI will not justify the initial investment or on-going investment due to low ARPU.”

Of course, the availability, indeed quality of connectivity depends heavily on where one is located. When it comes to the last point of contact within a shopping centre, on a campus, on a train or bus, or even workers risking their lives in a mine, different technological options are needed, according to Kamal Mokrani, global vice president at broadband wireless development business Infinet Wireless. ”There is, unfortunately, no single blanket solution that will meet the exact requirements in all scenarios,” he says. Our experience has shown that the challenges we would need to overcome in a shopping centre, as an example, are totally different from those we encounter in a mining environment where signal propagation can be affected by many geological structures and man-made obstacles.”

Mokrani says that when hundreds, if not thousands of retail customers, decide to go shopping at the same time, Infinet’s solutions tend to focus more on relieving the well-known bottleneck related to backhauling capacity, thus offering sufficient capacity to ensure both “high quality” voice calls and Internet access.

“High-speed connectivity for passengers on a train, bus or metro present us with completely different challenges, but ones which we have already been resolved in many of our deployments around the world,” he continues. All our wireless solutions are adaptable to the specific environment we are faced with, thanks to our approach in developing Software Defined Radio (SDR) platforms with all the flexibility they offer us and our customers. For example, when roaming between base stations deployed along the tracks for a train or a pre-defined route for other moving vehicles, seamless handover from one access point to another, whilst keeping latency of the data transmitted at its lowest level possible, is the biggest challenge for such high-speed mobility applications.”

These contexts all have subtly different principle drivers of the demand, argues Fletcher. “A shopping centre will be primarily focussed on B2C, while a mine would be more B2B as the driving force,” he says. “The nature of the data being transmitted wirelessly – B2B or B2C – will determine and push the economic principles that  shape the network deployment  principles. While FWA can provide a good group / shared connection on which to bolt a Wi-Fi access solution  and  would work for a shopping centre, mines are a well-understood scenario, often choosing to deploy a mobile micro BTS in lower spectrum bands to maximise coverage over wide expanses of  land, and even into the tunnel system itself. Trains and buses are a different scenario altogether and don’t really lend themselves to FWA solutions.”

Webb says   that the last point of connectivity must use a technology widely available in handsets, tablets, laptops and other devices. However, there are only two options - cellular and Wi-Fi. “Both are used in places like shopping centres where mobile operators are often keen to deploy cellular solutions alongside the shopping centre owner providing Wi-Fi,” he adds. ”In locations where mobile operators are less interested in deployment then only Wi-Fi is used. Many trains and buses now have Wi-Fi deployed within them.”

Historically, there was no ultra-high bandwidth alternative to fibre, but high performance FWA has emerged to fill the gigabit broadband desire when fibre is not an option. What’s more, technically, there are no limitations to bands that can be used to deploy FWA. In the case of LTE network deployments, operators often favour 800MHz, 1.8GHz and 2.1GHz bands for rural and suburban areas while using 2.3 GHz and 2.6 GHz for urban areas. The same strategy could be applied for FWA, however, due to the possibility of mitigating the adverse effects of higher propagation loss, it is feasible to also consider high carrier frequencies such as those in the 3.5GHz range where large bandwidths are more readily available.

Clearly a good solution for connectivity in even the most unforgiving of environments, but will opportunities for FWA  continue to open up as operators and service providers in the  region  realise the benefits of LTE-based  FWA?

“It’s just another, more cost-effective way to deliver coverage,” says Jordan. “The coverage it delivers will enable not only many more opportunities, but also creates services like eLearning, eHealth and eCommerce that will help to move the region forward. However, she says that legacy LTE-based fixed wireless solution deployment relies on a complicated deployment and configuration process during site installation. “This requires a complicated preparation phase and expert technician presence at the time of any new site installation,” Jordan adds.

Webb says opportunities for FWA already exist, citing every home and building without a broadband connection. Nevertheless, he says LTE is not the solution, because it is designed for mobile use and is too expensive and too low capacity for FWA. “To put it into perspective, a mobile user tends to have a monthly data consumption of about 5GByte/month, a home about 350GByte/month - 70 times more,” says Webb. “Using LTE or even 5G mobile to provide home broadband is like trying to use a car to transport 50 people - a coach is far better suited.”

In fact, Webb is rather blunt about LTE and 5G being used for FWA, calling it a waste of more costly infrastructure and due to densification and the transitory nature of mobile users coming in and out of the coverage area, the user’s bandwidth experience is not predictable or guaranteed. “FWA is static and so can be designed to provide predictable service which can be backed by service level agreements,” he argues. “There is a great deal of fibre deployed in places like Singapore, Korea, Japan and Malaysia making FWA more of a niche solution for urban residential/enterprise connectivity. However, FWA will always have a strong foothold in rural and suburban communities where the costs to lay fibre over dispersed dwellings remains largely prohibitive.” 

The changes that have occurred in recent years with the introduction of LTE, 5G and more advanced FWA technologies have clearly been monumental across a plethora of industry sectors. Mokrani says “the heightened consumer adoption of mobile devices is due to the lack of adequate fixed infrastructures” in many Asian countries.

“This has leveraged broadband wireless technology providers to play a much bigger role than traditional fixed operators by relieving the pressure for backhauling data and voice traffic from the mobile operators’ base stations to the rest of their network,” Mokrani continues. “Network operators of all types naturally want to spread the cost of installation and maintenance of any new technology across as many services and applications as possible.”

He argues that the largest opportunity Infinet predicts for FWA, whether LTE-based or others, will be in emerging countries where fixed broadband via legacy fibre, cable or DSL is simply not available today. “In developed countries, we are seeing strong signs that FWA technologies are giving service providers a more competitive edge over more expensive and sometimes unreliable wired alternatives,” Mokrani adds. “The biggest opportunity we see for LTE-based FWA specifically will be for the residential market, especially fuelled by the current Covid-19 pandemic where more and more people are having to work from home and demanding broadband speeds so as to stay fully operational and productive.”

Let’s look to the future. While microwave links have long been the cheap and effective solution, some believe there is now a real danger of usurpation by mobile tech such as 5G, whilst others see this in bigger towns and cities only.

Jordan says the approach adopted by fixed wireless service providers to network deployment is based on coverage limited or capacity limited scenarios. “In a coverage limited scenario, service providers main objective is providing acceptable coverage for a specific area considering targeted SLA for subscribers,” she explains. “In a capacity limited scenario, service provider addresses limited capacity in a geographical area by adding extra base stations in the specific geographical area already has coverage.”

Jordan says that although “the classical deployment will start with a ‘search ring’ identification”, following site acquisition and deployment; in many rural deployments, ease of deployment is the main objective for providers.

Mokrani argues that “there is no doubt that all types of wireless technologies have a significant role to play in improving broadband access in all parts of Asia. “Some of these technologies may still have a long way to go before they become universally accepted, with political and regulatory policies being the biggest obstacles to ubiquitous connectivity, but their acceptance and deployment are certainly crucial for bridging the digital divide between urban and rural areas,” he continues. “There is noticeably more demand for broadband connectivity in cities and bigger towns than rural areas simply because that’s where most companies and businesses are physically located. Mobile technologies such as 4G or 5G are not necessarily the most trusted platforms for a bank, as just one example, to establish connectivity between its branches and its headquarters as their managers value data security much more than anything else. They would most certainly deploy their own private networks, such as one based on FWA, and not want to share best-efforts network capacity from mobile networks with other users, ultimately exposing themselves to potential cyber threats and attacks. The same principle is also applicable to mission critical applications such as the fire brigade, the ambulance service and law enforcement agencies, all favouring a dedicated and private network for their own use only.”

As far as Webb is concerned, mobile technology is great....for mobiles. The problem, he says, is that “it is not designed” for providing broadband connection to buildings. “It is both very expensive as a solution to fixed broadband and lacks sufficient capacity, especially after providing service to mobile users,” Webb adds. “There are few examples of widespread FWA solutions using mobile technology and those that exist tend to require massive investment in a denser network of base stations. Better to use FWA - a technology designed for the purpose, with much more capacity and reliability.”

Lest we take it for granted, remember that incredible things happen when people connect to the internet or with each other. Whether the location is rural or urban, domestic, international, telco or cable, enterprise or residential, it sounds like optimised gigabit broadband solutions deliver the vision of global networking. FWA is addressing last mile deployment challenges timely, cost effectively and with increased speed and resilience. That can only be a good thing.