Spectrum propels 4G download speeds in SA

Admire Moyo
By Admire Moyo, ITWeb's news editor.
Johannesburg, 12 Oct 2023
Both 4G download and upload speeds benefit from more spectrum being used, says Opensignal.
Both 4G download and upload speeds benefit from more spectrum being used, says Opensignal.

Greater spectrum availability in South Africa has resulted in the country enjoying the fastest 4G download speeds on the African continent.

This is according to an analysis by Opensignal, which looks at the impact of greater spectrum bandwidth on the mobile network experience of African smartphone users on 4G mobile networks.

Opensignal analysed users’ experience across three different amounts of spectrum capacity used for 4G connectivity – 0-20MHz, 20-40MHz and above 40MHz.

It explains the size of the two latter buckets implies the use of carrier aggregation, which means connecting to multiple spectrum bands (carriers) at once.

“We observe relatively small numbers of readings with more than 60MHz of spectrum in our data across our African markets. This is why we included them in the ‘above 40MHz’ bucket,” says Robert Wyrzykowski, Opensignal analyst.

“As 5G services have only been deployed at a greater scale in South Africa, we do not focus in this analysis on the 5G spectrum, unlike in our previous articles on global trends or on the Asia-Pacific region.”

The analytics firm notes both 4G download and upload speeds benefit from more spectrum being used.

Doubling up

“Our users in Africa connected to larger spectrum bandwidths enjoy 4G download speeds around twice as fast as those connected to lower spectrum bandwidths – 4G upload speeds also increase, by 25%,” Wyrzykowski states.

“South Africa is a market where Opensignal sees both the fastest average 4G download speeds and the highest average amounts of spectrum used for 4G connections across Africa.”

After years of waiting, last year, the Independent Communications Authority of South Africa finally concluded the high-demand radio frequency spectrum auction.

The auction held by the telecoms regulator involved six qualified bidders: Cell C, Liquid Intelligent Technologies, MTN, Rain Networks, Telkom and Vodacom.

Cell C and Liquid acquired spectrum in the 3.5GHz and 2.6GHz bands, respectively. MTN, Rain, Telkom and Vodacom acquired 700MHz and 800MHz spectrum.

Opensignal also analysed the proportions of 4G readings per amount of spectrum used for South African operators.

The firm notes MTN has the highest proportion of 4G readings, with more than 40MHz of spectrum bandwidth used out of all South African operators – over 50%.

Meanwhile, Telkom users observe this spectrum capacity in only 5.5% of Opensignal readings – and in 57.1% of readings, the firm sees 20MHz or less spectrum used for 4G connectivity.

“The vast differences in the amount of spectrum bandwidth between MTN and Telkom impacts their average overall download speed scores – MTN won download speed experience in the last South Africa Mobile Network Experience report and Telkom came in last place,” says Wyrzykowski.

Opensignal adds that mobile users in many African markets still struggle with unrestrained access to mobile spectrum – even for 4G connectivity.

It notes the digital switchover is still ongoing and incomplete in some African markets, which is limiting the amount of spectrum available for 4G services.

In South Africa, communications minister Mondli Gungubele recently announced government had adopted a two-step approach to digital migration.

The first step, which was completed in July, focused on the immediate switch-off of analogue services above the 694MHz band to release spectrum for other telecommunications use.

Government will also temporarily accommodate some of the high population areas below 694MHz and switch-off within a given period. The set date for this step is 31 December 2024.

Opensignal notes 5G has only been commercially deployed in several markets, such as South Africa, Nigeria and Kenya, with the vast majority of African countries yet to assign 5G-capable spectrum in the 3.5GHz band.

“Spectrum is essential to foster the development of mobile connectivity in Africa, especially given the high numbers of mobile-only users – and the use of 4G spectrum will be key for many initial 5G deployments across African markets, like it was in Europe, Asia-Pacific or Americas,” says Wyrzykowski.

Mobile network experience

Looking across Africa’s regions, the report says more spectrum used commonly results in faster average 4G download speeds.

“We observe the highest relative uplift in Central Africa, of 89.6% – followed by Western Africa (72.3%) and Eastern Africa (64.3%) – while it is slightly lower in Northern Africa (46.3%) and Southern Africa (44.2%),” Wyrzykowski says.

“However, we recorded insignificant amounts of data for more than 40MHz of mobile spectrum being used in both Central and Eastern Africa, which means it’s rare for mobile users in these areas to connect to 4G services with wider spectrum bandwidths.”

Download and upload speeds are not the only metrics to consider when it comes to the impact of increased spectrum bandwidth on users’ mobile network experience.

Opensignal also analysed how this varied when streaming video services or playing multiplayer games on devices, with different amounts of spectrum used.

It says 4G video experience scores in Africa go from 53.4 points for spectrum bandwidth of 20MHz or smaller, up to 67.6 points for spectrum bandwidth exceeding 40MHz.

“These scores mean that when our users connect to 4G mobile services with 20MHz or less spectrum, their video streaming experience rates as ‘fair’ (48-58) – our users are, on average, able to stream video at 720p or better with satisfactory loading times and substantial stalling.

“However, when using 20-40MHz of mobile spectrum, they enjoy video experience rated as ‘good’ (58-68) – still able to stream video at 720p or better, but now with little stalling. With over 40MHz used, their experience stays in the same category, but only 0.4 points shy of the next category up – very good (68-78),” Wyrzykowski says.