Fiber planning for 5G networks

How fiber-optic planning for 5G networks should look like?

From backhaul…

Perhaps the most obvious place where more fiber is needed is in the backhaul – and not just for macro sites. There’ll be a proliferation of small cells as 5G players turn to higher frequencies (which have comparatively short signal ranges). Network densification of this sort is unavoidable if operators are to boost 5G capacity and improve indoor coverage. And those small cells, particularly in urban and congested areas, will demand backhaul capable of supporting huge amounts of traffic.  

 

True, wireless backhaul technologies might help in the near-term. But even here fiber points‑of‑presence will invariably be needed to go deep into the RAN. Without them, more wireless hops — links between antennas — become necessary to backhaul traffic to the network core. And since each hop adds latency, that’s not ideal if 5G operators want to support real-time video gaming, factory floor automation, augmented and virtual reality, and autonomous cars. Each of these applications demand sprightly latency times.

 

Performance-wise, then, it’s far better to rely on fiber’s near unlimited bandwidth for backhaul than microwave links or traditional copper T1/E1 connections. It’s the long-term solution. 5G networks will be around for at least a decade.

…to fronthaul

Aside from network densification, fiber planning will play a key role in migration to centralized RAN (C-RAN) architectures and Cloud RAN. In both instances, getting the fronthaul part right – the link between the Baseband Unit (BBU), which processes user and control data, and Remote Radio Heads (RRHs), the antennas – is crucial.

 

C-RAN is not unique to 5G. Some operators have started deploying C‑RAN architectures for 4G, but they’re also a key 5G component as operators strive to lower operations and maintenance (O&M) costs. Cloud RAN, another stage in access network evolution, similarly disrupts traditional ways of doing things. Network planners have got their work cut out if they don’t have the right fiber planning tools.   

 

Let’s look at C-RAN. Instead of BBU and RRH co-location at the same cell site – the traditional RAN architecture – BBUs from the same local area are relocated from their cell sites to a common aggregation point. One BBU can then serve multiple RRHs using fronthaul links.  

 

With Cloud RAN, however, BBUs are no longer hardware units but virtual ones running on generic servers. Hardware resources can be allocated dynamically to a virtual BBU in a local area to meet fluctuating RRH demands. Better load balancing of mobile traffic, and tighter coordination of interference for more efficient use of the frequency spectrum, then becomes possible. Energy savings (better utilisation of hardware) and lower O&M costs (fewer BBUs and reduced equipment complexity on cell sites) can also be achieved.

 

In both cases – C-RAN and Cloud RAN – fiber is the ideal fronthaul medium in 5G environments. Not only for handling large volumes of traffic, but also for latency and reliability.  

Clever RAN planning…

There’s no getting away from it. 5G, if it’s to have mass appeal to consumers and attract businesses, will need a radical RAN overhaul. Operators may bristle at the thought, but expert and cost-efficient network planning can take much of the pain out of RAN re-building and fiber rollout.

 

Moreover, if the proper operational procedures are in place – different network planning teams collaborating rather than working in silos – there’s potential scope for cost-saving synergies for operators offering both mobile and broadband services. 5G and bandwidth-hungry 4G cell sites, for example, may well be integrated into the design of fiber-to-the-home (FTTH) architectures.

 

Conversely, a push on 5G coverage and edge computing might prompt operators to roll out FTTH in the same area, since infrastructure segments can be shared. Shifting computing processing and storage capabilities to the network edge, and so closer to users, is necessary if 5G operators are tap into new revenue-generating services that require ultra-low latency times. Again, edge computing will likely require additional RAN fiber.

 

For network planning of this sort to happen – whether it’s for a standalone 5G network or a converged fixed and wireless play – an up-to-date and complete picture of existing network assets is the first step. Planners need to know, with a fine degree of accuracy, the capacity of the current network. Knowledge of which existing network elements might be optimised to increase capacity is also required. Only then can planners start to think about optimal fiber rollouts to meet projected increases in bandwidth demand.

…needs sophisticated tools

Network planning should always take account of business case considerations. SunVizion Network Planning, developed by Suntech, is a sophisticated solution focused on return of investment (ROI). By extending SunVizion Network Inventory with a sophisticated planning module, operators are well placed to address the formidable network planning challenges posed by 5G and the pressing need to install more fiber in the RAN.

 

SunVizion Network Inventory is the bedrock of network planning. It provides operations staff with clear and accurate visibility of existing network plant, both outdoors and indoors.  They can easily identify the whereabouts of infrastructure (ducts, manholes, sites, cabinets, etc.), fiber network (cables, splice closures, splitters, etc.) and RAN (BBU, RRH, antennas, etc.) - outside plant, and even have knowledge of room equipment and its location - inside plant.

 

Add SunVizion Network Planning into the mix and network planners can get off to a flying start. Let’s imagine a 5G network operator has identified where it needs cell sites and edge computing in a town. The SunVizion Network Inventory app, working in tandem with SunVizion Network Inventory, can automatically – in a matter of minutes – give details on a plan for fiber rollout. Looking at a digital map of the town in question, network planners can see where it’s possible to reuse existing infrastructure, and where new trenches should be dug. They’re alerted too as to which works should be done before others and how long the buildout should last. Subcontractors can see exactly what is required.

 

The network-planning module is designed specifically to reduce time and cost of implementing new services and architectures. Unique algorithms based on variety data sources optimise the planning process. Not only is existing infrastructure and an area’s topography taken into account, but the possibility and cost of leasing equipment from other operators becomes part of the planning mix. Thus planners can quickly design the most optimise runs of Fiber To The Cell Site (including picocells and femtocells), FTTA (fiber to the antenna), FTTB, FTTH, as well as the most optimised location of planned point resources (active devices, passive devices, manholes etc.). Detection of power-supply conflicts, and calculation of power consumed by each network element, are other features of SunVizion Network Planning & Design.

 

Importantly, the SunVizion Network Planning app gives a detailed lowdown on how much investment is required. Costs associated with devices, cable, pipe and trench digging are individually itemised. Infrastructure leasing fees are also accounted for. If ROI proves attractive, operators have a readymade plan in place. Instead of spending weeks to come up with a ready plan network designers planners can pursue other important tasks, such oversee the whole planning process.

Better ways of working thanks to fiber planning

There are other benefits to the Suntech approach. Traditionally, network inventory and planning are two separate systems. Only when network upgrades are completed is the network inventory database updated. That’s not ideal for network designers. They’ll want to keep constant tabs on resource availability during the network development stage.

 

Moreover, because inventory and planning typically use different data models, there’s a need for manual importing of data from one system to another. This process is time consuming, costly and prone to error. SunVizion network planning and network inventory systems, on the other hand, are entirely compatible because they use the same database. Any network changes can be easily and immediately logged.

 

Operators might think it unnecessary for network maintenance staff to see what network resources are under development, however. That’s not a problem for SunVizion because it allows for a ‘multi-version’ inventory database. It means that maintenance staff can be restricted to seeing only existing resources (main version), while network designers can see both existing assets and resources under development (‘planned’ version). If employees of some departments need to view devices already connected, but not yet active (e.g. to estimate the time of delivery of the service to the customer in a given location) the system also gives such a possibility.

 

When network development is complete, updates are synchronized with the main version accessed by maintenance staff. The whole process is performed in one environment, which eliminates errors in the data and drastically shortens the time of the entire operation. Maintenance staff can see new network status few minutes after completing network extension plan. By capturing data from network management systems SunVizion can automatically detect whether the actual configuration of the devices made by the subcontractors are according to what was planned. Neither is there any reason why 5G and FTTH planning designer teams should work in silos. By using the same network inventory database provided by Suntech, which allows a holistic and up-to-date view of all assets, they can see what each other is doing on the network. SNP has a unique mechanism that allows different network planners to merge projects.

 

Operators can navigate a profitable path to a RAN primed for 5G, but only if they ditch inefficient ways of network planning.