The wide range of factors we must consider make planning our network a considerable challenge.
Selecting a new site
Choosing a site and design for each new base station presents a challenge. We must balance technical requirements and community concerns, which often conflict. For example, higher masts can sometimes improve coverage but can also have greater visual impact. We want to roll out our network quickly but community consultation is vital and can take time.
We need to balance community considerations including:
- Public concern relating to schools, hospitals, nature reserves and other sensitive areas
- Visual impact on the landscape
- Compliance with local planning regulations
- Minimal disturbance to the community
- Access to information
- Consultation
with technical considerations such as:
- Compliance with local RF field strength guidelines
- Good coverage, capacity and improved services
- Strong and safe construction
- Efficient rollout
- Appropriate positioning to connect to the network
- Easy access and maintenance
- Access to power supply.
Improving coverage and capacity
The areas covered by base stations are known as cells. A cell can cover up to several kilometres radius in open country and as little as one hundred metres in built-up areas or inside buildings. Each cell – split into up to three sectors – overlaps with the sectors of neighbouring cells to create an uninterrupted mobile phone network, but must use different frequencies to avoid interference. See how mobiles work.
The coverage and capacity of our mobile services are determined by the number of base stations in our network. Improved coverage is achieved by extending our network to new geographical areas or by entering into network sharing agreements with other operators.
Increased data capacity means more calls can be handled in the same location and enables us to introduce new services such as video calling, mobile internet and mobile TV on our 3G networks.
Capacity can be increased in several ways:
- Additional frequencies in the spectrum can be acquired or redeployed, enabling more cell sectors to overlap
- Improving efficiency in use of the spectrum through technological innovation
- Establishing new wide-range cells that operate in all directions, to provide 'umbrella' coverage
- Introducing microsites within buildings
- Improving radio links to enhance system and processing capacity.