This week we have launched our network densification page and we thought what better way to commemorate this than to share some more of our insights into the technology. As we touch upon the subject of small cell challenges on the page we wanted to take the opportunity to now take a more in-depth look.
The popularity of small cells has grown rapidly in recent years as demand for data increases. This is due to the invention and proliferation of smart phones, highly personal devices which are often more important to users than their wallet. Crucially smart phone apps consume large amounts of data, and users expect their apps to work everywhere. Cellular coverage footprint per site will inevitably become smaller and smaller as mobile traffic continues to grow exponentially. Mobile operators are looking at ever more creative methods of providing ubiquitous coverage and capacity using small cells, especially in urban areas where the demand is greatest. However, small cells have their own set of challenges which need to be taken into consideration when being deployed, including the availability of space, power and connectivity to the mobile operator’s core network.
One of the biggest challenges for small cells is mounting small cells on street assets which can be complex because of the variety of considerations they represent. Firstly you need to understand what street assets are available to be used by small cells. To establish this, you need to find out the rights and concessions by contacting the relevant agency or owner in control of them, such as local authorities. This may result in the need to obtaining planning permission before works can commence.
Once ownership that has been determined, you need to know the types of assets available. Street assets come in a variety of forms, such as lampposts, telephone boxes, telegraph poles, bus shelters and billboards. Each type of asset represents its own set of restrictions and opportunities, which are include asset height, structure and power. These factors will have a major impact on the coverage footprint of the small cell. Additionally, the availability of a suitable power source is an essential consideration as a certain level of power and space is needed for the small cells to operate. The cost of installing power to an asset is high and quickly outweighing the benefits of the small cells so power needs to be readily available for an asset to be viable.
A further challenge is the transmit power level. This should be set to ensure that nearby users connect to the small cell rather than a macrocell, whilst not causing interference to neighbouring small cells. This is a delicate balancing act that needs careful consideration. Small cells are often deployed in areas where a marcocell provides coverage but not the capacity needed. This particular challenge can be mitigated by the mobile operator introducing a new frequency to operate the small cells.
Off-loading of mobile data to Wi-Fi or licensed small cells requires access to a high speed reliable backhaul connection to route the data to the mobile operator’s core. One of the challenges here is that the backhaul network is often not under the direct control of the mobile operator. Fibre is often used to provide backhaul to outdoor Small Cell networks, with each fibre connection typically providing access to several wireless meshed Wi-Fi or Small Cell devices.
Currently street assets are used on a first come first served basis by MNOs. Not all street assets are available or appropriate for the use of mounting antennas so as one MNO selects a site, the choice of remaining assets become limited for other MNOs. Traditionally small cells are single operator and with limits to the number of devices per street asset means the choice of street assets becomes very limited once an MNO has deployed a solution. This highlights the advantage of being the first MNO to densify an area. Careful and clever design work can help over the issue but the big game changer will be multi operator small cells. Although MNOs will need to collaborate on small cell deployments it will overcome the real issue of the shrinking pool of available street assets.
Regular optimisation of the cellular network is needed as demand evolves, driven by changes in footfall, dwell times and device usage. Small cells may need to be reconfigured or additional small cells added.
iWireless Solutions has carried out numerous small cell projects so if you wish to find out more have a read through our case studies and news to find posts such as Rapid Microcell Deployment. In fact, we are currently involved in a major outdoor small cells project in part of central London where users are currently experiencing a poor mobile service, as announced in “iWireless Solutions wins major telco contract”. Alternatively, get in touch to speak to one of our technical specialists by email on email@example.com or phone us on 01342 305038.