There is a growing sense that it is time to update our perception of mmWave and cast old prejudices aside. That is the message emanating from the currently frigid city of Harbin in northeast China, where Huawei has just completed a trial with the country’s third largest MNO, China Unicom, during winter sports competitions taking place there.
Tests took place In the Harbin Ice Hockey Stadium, where the two employed 5G-Advanced (5G Standalone) mmWave technologies, featuring coordination with sub-6 GHz 5G bands to deliver robust aggregate 10 Gbps connectivity. Peak speeds exceeded 10 Gbps, demonstrating download of 10 GB in 10 seconds, but more pertinently perhaps the ability to stream 8K video to multiple users simultaneously in the crowded arena.
The most intriguing aspect of the trial was the affirmation of mmWave’s credentials for what is increasingly being called the “low altitude economy.” This is a phrase we are going to have get used to, or sometimes the slightly restricted “low altitude transportation.” A lot of it is about transportation, from air taxis to delivery drones, but there is also surveillance including pursuit of criminals, monitoring of equipment, and conducting aerial surveys.
It was this aspect that China Unicom and Huawei majored on, telling how the former’s network engineers were given morale-boosting refreshments by delivery drones communicating over the composite mmWave/mid-band links. They anticipated this accelerating rollout of services such as low-altitude logistics, sightseeing, and transportation.
David Li, President of Huawei’s 5G & LTE TDD Product Line, added: “5G-Advanced mmWave breakthroughs in the coordination with low bands and mobile connectivity in low-altitude spaces improve network performance for both major sporting events and the low-altitude economy.”
This example highlights the fluctuating fortunes of mmWave over the 5G era, whose stock began high, sunk, and then rose again, first on the back of FWA (Fixed Wireless Access) and now this low altitude economy. Meanwhile, it is even coming back into favor for urban densification in some areas, including the USA, where Verizon has been pushing this aspect the hardest after getting its fingers slightly burned in the first two years after its 5G launch in 2019.
In fact, around or just ahead of the first launches, 5G was heralded as being all about mmWave, because of the much greater available capacity and higher performance. Verizon embraced this ethos more enthusiastically than many of its peers, promoting the benefits of its mmWave network, which indeed produced some very compelling bit rates.
But these were only obtainable quite close to base stations, such that aggregate performance across a cell was much less remarkable. Many users were underwhelmed, especially those moving around a lot, who were sometimes outside the peak coverage area.
Verizon then de-emphasized mmWave for urban mobility, but then later deployed it increasingly for FWA, as demand for that grew. The US was well-placed, with quite a lot of remote rural areas where it was often uneconomical to bring fiber close to dwellings. FTTH roll out costs in the US tend to be higher than most other countries generally, and especially in more sparsely populated areas, making FWA cost-effective.
At the same time, the fact FWA involves fixed CPE, permanently powered rather than relying on batteries, makes it more conducive for the high gain technologies that extend range, capacity and performance. That power budget is not available in mobile devices.
Samsung has been notably active researching both stronger Power Amplifiers (PAs) and high-resolution beams that take advantage both of the fixed CPE and the direct connection to the grid that enables greater computational intensity. Samsung has been able to demonstrate substantial increases in Reference Signal Received Power (RSRP) over both the downlink and uplink.
It is notable also that those restrictions that hampered Verizon in the early days have become more relaxed with further progress. It has taken some time for perceptions to catch up with some of the new realities, given that until just two years ago, a number of Tier 1 operators were still arguing that mmWave would not be fit for any purpose in the foreseeable future. Few are saying that now.
Firstly, the severe distance limitations have been overcome with more concentrated beam forming and antenna gain technologies, which have allowed Australian operator NBN with Nokia mmWave FWA CPE to extend its FWA footprint to dwellings previously only served by satellite, in some cases reaching multiple gigabit speeds over distances up to 7 km from a base station. Then in January 2025, NBN went further, this time with Samsung equipment over a 26 GHz FWA link, reaching 10 km.
This was with Line of Sight (LOS). Now, even the perception that mmWave can only work over LOS is being challenged, by the latest wide field technologies capable of juggling between multiple signal sources, at least for FWA at this stage.
Nokia showed the way in February 2024 when it launched a 5G outdoor FWA receiver designed to enhance coverage in all settings, urban, suburban, and rural areas. Mounted on a wall, pole, or balcony, the receiver employs 360-degree field-of-view technology combined with algorithms developed at Nokia Bell Labs to create digital fingerprints of available radio signals.
This allows it to track and switch quickly between signal sources to ensure the best possible connection is maintained between base station and receiver. Nokia has in turn integrated high gain antennas to maximize the range of this FWA system that was billed as the first to operate in Non-LOS (NLOS) conditions.
This pivots back to the low altitude applications, where there is potential to circumvent the NLOS issue. That in effect is the objective of Reconfigurable Intelligent Surfaces (RIS), or a variant called Intelligent Reflecting Surfaces (IRS), which are being investigated for airborne deployment of mmWave. Drones would be controlled by mmWave links while also extending them through reflection.
This has potential in urban settings, where low altitude drones could enable chains of LOS connectivity between points which are not themselves directly within line of sight of each other. In this way a combination of UAVs and mmWave technology could enable much higher capacity and bitrates in dense urban settings than would be possible with conventional small cell-based densification on the ground.
Even without this innovation, mmWave is figuring increasingly for urban densification in combination with mid band, effectively for overspill capacity. Devices close to base stations transmit in mmWave bands, leaving more mid-band capacity to serve those further away.