High level capacity analysis and the need for site densification

The following section addresses the impact of demand on capacity at a high level by taking our three demand scenarios and mapping the capacity on top of them. This analysis demonstrates how the mix of capacity techniques, spectrum and spectral efficiency are combined to give an overall level of capacity that can meet one or more of the demand growth scenarios.

We start the analysis by establishing the level of demand growth which is discussed in detail in section 3.4 and presented as a set of demand scenarios across each of the study areas. The growth in demand varies widely across this range based on the population differences across the study areas and the low, mid and high growth assumptions. The urban high scenario has the highest demand out of all the scenarios shown and we expect this scenario to require the greatest capacity.

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Scaling of Spectral Efficiency for Geotype, Carrier Frequency and Indoor/outdoor Consumers

Outdoor 800 MHz Indoor 800 MHz Outdoor 1800 MHz Indoor 1800 MHz Outdoor 2600 MHz Indoor 2600 MHz

Figure 4-5 Range of demand scenarios or each of the study areas

The next step is to quantify the components of supply which are spectrum and

technology. These capacity components have been discussed in detail in sections 3.5 and 3.8 respectively to illustrate the varying quantities in terms of MHz and bps/Hz that can serve the growing demand.

The charts in Figure 4-6 and Figure 4-7 show the spread of available capacity in each of the low mid and high scenarios. The quantity of available spectrum, increasing over time, represents a plausible range of the mix of mobile bands likely to be available across the time frame and that could be deployed by operators to serve capacity.

The quantity of site spectral efficiency represents a plausible spread of capacity and technology evolution likely to become available over the project time frame with some technologies such as LTE-Advanced able to meet the low case spectral efficiency in 2030 using today’s solutions.

Figure 4-6 Range of spectrum scenarios for the urban and suburban study areas

Figure 4-7 Range of site spectral efficiency across the low, mid and high scenarios

The combined available capacity is calculated by multiplying the spectrum and spectral efficiency together to give an overall capacity value in Mbps. We can illustrate how capacity maps on to demand by normalising growth from 2012 to give the relative growth for each demand case on to the same chart as shown in Figure 4-8.

Figure 4-8Mapping capacity on to demand for low, mid and high cases of demand

The left-hand plot in Figure 4-8 shows the high demand, low capacity case for the urban study area where demand outstrips supply by a very large margin out to 2030. The red line is the available capacity level which reaches a maximum of 20x growth from 2012 compared to 220x growth from 2012 for demand. This case would require supplementary capacity such as extra sites to meet the demand growth as all other capacity techniques are exhausted.

The middle plot in Figure 4-8 shows the mid case for the urban study area which shows capacity exceeding supply for the first ten years of the time frame after which supply and demand tend to follow the same trend with some overlapping points until 2028 when demand begins to outstrip supply. This case would require a much lower number of extra sites compared to the high case. A steady increment of sites over the first ten years would be required to meet the demand in each year, with spectrum and technology combined providing the balance of capacity supply.

The right-hand plot in Figure 4-8 shows the low demand, high capacity case for the urban study area where the capacity outstrips demand by a large margin out to 2030. The capacity reaches 120x growth from 2012 compared to demand which reaches only 20x growth from 2012. This means spectrum and technology on its own is capable of meeting the demand with no requirement for extra sites.

Based on the analysis given above we can determine the number of sites required using the urban mid case as an exemplar by dividing the demand by the capacity. Figure 4-10

shows the number of sites needed to supply capacity over the project time frame and also how the introduction of 700 MHz in 2020 and 2026 has an impact on it.

It can be seen that the number of sites starts in 2012 with 240 sites to meet demand in the urban study area, by 2013 the number of sites needed is greatly reduced. This is based on a 3x increase in spectrum in 2013 driven mainly by the availability of 800 MHz and 2.6 GHz on to the market. Although the sites are already built they are used to provide the capacity and coverage necessary for the next 11 years (to 2024) by which time more sites will be needed. The chart also shows how introducing 700 MHz in 2020 prolongs the amount of time the capacity can serve demand without needing more sites until around 2028. This can be compared to the 2026 line where sites are needed earlier indicating the advantage introducing new spectrum earlier can offer.

Figure 4-9 Number of sites need to supply capacity in the urban mid case

Figure 4-10 presents the number of sites needed for the urban study area across all of the low, mid and high cases to compare against the cases where sites are needed or not. It can be seen that in the high demand case there is only 3 years elapsed time where sites are not needed. This is because the capacity (spectrum and technology) alone is not sufficient to serve the demand and runs out relatively quickly and by 2015 more sites are needed. It is also noted that over 3000 sites will be needed by 2030 to meet this demand which could be deemed impractical in reality. In contrast, the low demand case shows there is so much capacity, that no additional sites are needed and spectrum and technology alone can serve the rate of demand growth over the time frame.

Figure 4-10 Sites needed to supply capacity for urban study area across all low, mid and high cases A further comparison can be made between the urban study area and the rural study area to capture the capacity limitation differences and total number of sites needed to meet demand. Figure 4-11 shows the number of sites needed to supply capacity for the rural area. The behaviour in between the low, mid and high cases is very similar to that of the urban study area. However, in rural it can be seen that fewer sites are needed in 2012, around 70 compared to 240 in the urban study area this is due to the lower demand density (and capacity limited) in rural areas compared to the urban area and therefore fewer initial sites to meet that level of demand. In the high case for rural by 2030 there are still around 1000 sites needed to meet the demand.

Figure 4-11 Sites needed to supply capacity for rural study area across all low, mid and high cases

In summary, the high level analysis has shown how dividing demand by potential site capacity gives the number of sites needed across each of the low, mid and high cases of demand. It suggests that given the 3x increase in spectrum in 2013 reduces the number of sites needed, and postpones further densification and thus cost of network roll out.

More specifically it shows that:

• High demand, low capacity: Require no new sites until 2015

• Mid case: Requires no new sites until 2024-2028

• Low demand, high capacity: No densification needed

It should be noted that the capacity analysis does not consider coverage or the special qualities of <1GHz spectrum, so only the quantity of the 700MHz spectrum matters which we have assumed as 40MHz bandwidth resulting in 5-9% of total spectrum. The next section addresses the details of the results which incorporated the complexity of site upgrade configurations, spectrum band upgrade configurations and new site builds. In principle we should see the results follow the trend of the high level analysis.