When a high-end smartphone displays a 4G or 4G+ connection, it is assumed it is connected to an LTE or LTE-Advanced network.
But what does it mean for a network to be LTE-A, and how does a phone decide whether it is on LTE or LTE-A?
Tech-savvy users will know that LTE-A is Category 6 LTE. This means it is LTE that supports technologies such as carrier aggregation and multiple-input and multiple-output antenna designs, allowing greater data speeds.
Carrier aggregation refers to the ability of the network and a device to combine the capacity a network has that may be scattered over the radio frequency spectrum into a single channel.
For example, a mobile operator in South Africa may have spectrum in the 900MHz, 1,800MHz, and 2,100/1,900MHz frequency bands.
When unsupported phones connected to a network, they would connect in one of these frequency bands and only have access to its maximum bandwidth, which was always smaller than 20MHz.
With carrier aggregation, bandwidth across multiple frequencies can be combined to give devices access to chunks of bandwidth larger than 20MHz, translating into faster speeds.
This raises the question: If a network supports Category 6 LTE and carrier aggregation, but still can’t provide bandwidth greater than 20MHz, does it still provide LTE-A?
If this is not the case, then networks in South Africa may not be able to claim they are providing true LTE-A – as the spectrum afforded to them by the government is limited.
Samsung told MyBroadband that under default configurations, its devices will only report a 4G+ connection if:
- The network supports Category 6 LTE.
- If the total combined bandwidth exceeds 20MHz.
Samsung allows networks to customise these parameters, allowing many South African networks to display “4G+” on Samsung devices.
“Samsung’s global policy regarding the display of the LTE/LTE-A/4G/4G+ network icon is that the network icon display is operator configurable upon official request and Samsung approval,” it said.
It added that the display of the 4G+ icon is determined by the capability of the network, not the resource allocation to a device or throughput.
Changing 4G+ for South Africa
Samsung said it has received a request from a local operator to display 4G+ based on a total combined aggregated bandwidth of 15MHz, which the company has approved.
“The changes are in the process of being implemented and rolled out to XFA devices,” said Samsung.
XFA refers to the firmware version used in devices provided to certain operators in South Africa.
In the case of the Samsung Galaxy S7 and Galaxy S8, the XFA firmware is used in all non-Vodacom devices.