Thursday, October 8th, 2015 (1:02 pm) - Score 1,961

Chinese firm Huawei and Japanese telecoms giant NTT DOCOMO have conducted the world’s first large-scale field trial of next generation 5G mobile broadband technology using the sub-6GHz band, which has been able to achieve an impressive peak speed of 3.6Gbps (Gigabits per second).

Admittedly the International Telecommunication Union‘s (ITU) related IMT-2020 standard has already defined the top speed that 5G should aim to achieve as 20Gbps, which is still much more than the 3.6Gbps delivered above, but it’s a bit more complicated than that.

Until now most of the early 5G “tests” (not trials like this one) have been conducted under lab conditions and nearly all of them have involved the use of significantly higher frequency spectrum, which can carry more data but struggles to travel very far or to penetrate through solid objects (e.g. walls).

For example, a test conducted by Samsung last year delivered speeds of 7.5Gbps (here), which fell away to 1.2Gbps when the same setup was tested while travelling at just over 60 MPH (Miles per hour) on a 4.35km long racetrack; but that test made use of the 28GHz radio spectrum band. Elsewhere another demo by Nokia Networks achieved 10Gbps, but again that was only possible with the 73GHz band (here).

The obvious problem with such high frequencies is that they would require a new type of network, which could also be more expensive, in order to deliver that kind of performance over a wide area. By comparison Huawei’s trial was conducted in the much more familiar sub-6GHz band.

The field trial itself was conducted at an outdoor test site in Chengdu (China) and made use of several new air interface technologies, such as Multi-User MIMO (concurrent connectivity of 24 user devices in the macro-cell environment), Sparse Code Multiple Access (SCMA) and Filtered OFDM (F-OFDM).

Apparently the average cell downlink throughput of MU-MIMOs was 1.34Gbps, while 3.6Gbps was the peak recorded throughput in a 100MHz ultra-wide band channel. However it’s noted that Huawei also has a 5G SU-MIMO prototype, which can deliver a peak of 10Gbps by using 200MHz of bandwidth in the sub-6GHz band.

Takehiro Nakamura, VP and MD of NTT DOCOMO’s 5G Lab, said: “As the first in the world to succeed with such a large multi-user environment test, this is an important milestone. This is very encouraging as the industry works to commercialize 5G by 2020. Both Huawei and DOCOMO teams have made tremendous efforts. I look forward to even more impressive results when we move to the next phase of field trial in Japan.”

Dr. Wen Tong, Huawei Fellow and CTO of Huawei Wireless, said: “This joint field trial represents a significant advance toward fulfilling Huawei’s commitment to developing 5G technology standards before 2018. Results like these show we are making rapid progress and are on the right path. I am confident that what we have learned here will be reflected in even more innovative technological advances as we continue working on 5G research.”

The news is impressive, although it’s worth noting that we’re not given any information about distance (i.e. how far the signal travelled in order to achieve the above speeds) and that’s a crucial consideration.

At the same time sub-6GHz is good, but it’s still a long way off the more familiar 800MHz to 3.6GHz bands that are so often used by current generation 4G (LTE) technologies in the United Kingdom.

In keeping with that the UK telecoms regulator, Ofcom, is currently only working to identify spectrum between 6GHz and 100GHz for use by 5G services (here). This is a demonstration of why it can be risky to decide any policy or spectrum allocations before a final technology has been agreed, but Ofcom do appear to understand that too.

Huawei now plans to launch the first 5G pilot networks with its partners in 2018, with the aim being to complete interoperability testing during 2019 and just ahead of the generally accepted commercially launch window in 2020.