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There’s been a lot of buzz about 5G over the past year – a lot of it, sadly, none too coherent. Today we will provide a detailed, realistic see how we can expect 5G to improve cellular broadband, with a focus on the impact we might expect on gaming. Surprise: the news is actually not bad!
What is 5G?
Before we can talk about what to expect from 5G, we need to talk about what 5G really is – and not. 5G, short for “fifth generation”, is the next cellular communication protocol. 5G is not, specifically, any given frequency as a band. There are two main bands of which 5G can operate – millimeter wave, and sub-6GHz. Exactly what frequencies within those bands your devices will vary from carrier to carrier, and country to country.
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The sub-6GHz band is not new territory; the frequencies in use are the same as carriers already use for 4G / LTE service. Sub-6Ghz can be further divided into low band – below 1GHz – and mid-band, at 2.5GHz-3.5GHz. Low-band offers greater range of the tower, but at lower speeds; the midband offers greater speed but lower range. It is worth noting that “lower range” is not necessarily a curse – the larger the range of the tower, the more users you have the same definite amount of air time, and the lower the speeds and less predictable the latency you have. t you will see.
Although we expect 5G to be significantly better than 4G on sub-6GHz bands, millimeter golf—Round 24GHz-39GHz in the US – is what specifically refers to most of the breathtaking 5G coverage you’ve seen in the past.
The amount of low bandwidth available for millimeter waves – or just “mmWave” for short – is pretty crazy. The spec shows 800MHz individual channel width, allowing us to expect edge data rates (the lower limit of rates you would see from a reliable connection) of 400 Mbps.
But streaming is usually not the killer metric for gaming—latency is. We’ll take a more skeptical eye here later, but mmWave is ultimately expected to deliver OTA (over the air) latency of less than one millisecond.
A closer look at sub-6GHz 5G
At this point, you may be wondering why anyone is obsessed with sub-6GHz bands in any case, if they are not and can not offer comparable bandwidth, throughput and latency to mmWave. Although mmWave can certainly handle low or midband connections, it has some pretty serious drawbacks. In short, the higher the frequency of a given band, the less capable it is of penetrating obstacles.
At less than 1GHz, the sub-6GHz low-bandwidth flavor is barely affected by most obstacles – you typically need something in the order of a mount between your device and the tower to make a significant impact on connection quality. But you also have very little bandwidth to work with, limiting maximum speeds. Nowadays, you can see 100Mbps or even 200Mbps from a 5G low-bandwidth connection – but those numbers will almost certainly drop sharply as 5G adoption takes off.
Mid-band – 2.5GHz to 3.5GHz – is a good compromise for urban areas. It does not penetrate walls and similar obstacles, as the low band does, but that is just as much a blessing as a curse – lower penetration makes it easier for a large number of towers in a device close to a few square miles to operate without interfering as many with each other. Mid-band 5G is slightly higher frequency than modern 4G, whose higher band typically runs just below or just above 2.4 GHz Wi-Fi.
Mid-band channels are wider than low-band channels, with proportionally higher speeds – ranging from 125 Mbps at the low end, to 500 Mbps or higher under more ideal conditions.
A realistic look at mmWave
This brings us back to millimeter wave – the Shangri-La of 800 MHz channel width, sub-millisecond latency and free puppies for everyone. At least, that’s what a lot of the marketing around 5G sounds like.
The problem is, mmWave frequencies are absolutely awful at penetrating obstacles. We finally spoke to Qualcomm engineers, who confirmed what we already knew about 30GHz-40GHz RF – it will not directly affect buildings. With that said, mmWave is a lot more useful than you might think based on that one fact alone.
Jim Salter
Although mmWave frequencies do not penetrate directly to exterior walls, they bounce well off hard surfaces – and the resulting propaganda for multiple paths of radio frequency is absolutely useful. In September 2019, a PC Magazine reporter demonstrated that it was better than 400Mbps on the wrong side of an elevator shaft of a 5G panel, and more than 1Gbps on the other side of an interior wall.
The usability of RF multipath propagation – “echoes” jumping from hard surfaces such as concrete buildings and sidewalks – makes mmWave a reasonably ridiculous proposition for outside users. The range is still fairly low compared to frequencies in the midband, but this is (again) as blessed as it is cursed. Lower range means you need more towers, but it also means relatively fewer users per tower, less interference from fewer other users within “honor shot”, and thus more airtime to get effective per user.
The expected widespread availability of mmWave for outside users will have a major impact on the quality of mid-band available for inside users. (Remember, there is only so much air time to go around.) If you can divide your charge among non-overlapping spectra by serving outside users with mmWave and inside users with mid-band sub-6GHz, the how much air time for each sharp up.
