One of the big themes at Mobile World Congress this year will be millimeter wave spectrum – not just the technology, but the realities of deploying cost-effective 5G or WiFi 6 networks in these plentiful, but challenging, bands. A great deal of engineering effort has been made in the unlicensed 60 GHz band, and the 3GPP industry is starting to catch up as operators in the USA, Japan and other countries deploy mmWave networks, or plan to do so soon.
Start-ups and established vendors are vying to address the challenges of short signal range – and resulting high costs of the very dense networks required – as well as getting chips into mass market devices. Among them, RF specialist Movandi stands out with the launch of its BeamXR repeater, which will be available later in the year. The company, which has focused on Bluetooth and WiFi in the past, has now built a 28 GHz box and is developing a 39 GHz one, to cover the two main mmWave bands in use in the USA. Next year, it plans to have a dual-band unit supporting both bands, or other mmWave options which are being adopted elsewhere (26 GHz, for instance, is designated as a 5G candidate band by the ITU and various governments including the European Union).
Repeaters are traditionally a low cost way to extend coverage, especially indoors but are not usually associated with mmWave. But co-founder & CEO Maryam Rofougaran says the repeater is an important way to get around the biggest downside of mmWave spectrum, its short range. The unit can be used indoors or outdoors, placed between the 5G base station and the CPE, hotspot or mobile device.
Rofougaran said: “BeamXR solution is transformative and can accelerate large-scale 5G commercialization by reducing infrastructure costs, simplifying deployment and increase network capacity, without impacting latency.”
The company claims that BeamXR helps mmWave signals to penetrate buildings or bends the signal around a building. It is also more compact, more power-efficient over a wider power range, more spectrally efficient, and cheaper to produce than first generation mmWave antennas, says the company.
As well as the BeamXR, Movandi also announced a new alliance with NXP, which will work with the smaller firm on mmWave products that will combine NXP’s Layerscape family of ARM-based processors and Movandi’s RF transceiver and systems architecture.
Meanwhile, among Nokia’s pre-MWC announcement were two new members of its AirScale small cell portfolio, one an mmWave product for dense outdoor hotzones, the other a mid-band indoor device designed to offer a smooth migration from 4G to 5G.
The 5G AirScale mmWave Radio supports the USA’s preferred bands, 28 GHz and 39 GHz, in a compact, high power format. It allows for 180-degree, 360-degree and multiband deployments to provide flexible ways to address the challenges of mmWave signal attenuation.
In a centralized or virtualized RAN configuration, it supports eCPRI fronthaul to a distributed data center; and it can also support baseband unit functionality using a modular compact component.
The 5G pico Remote Radio Head for the Nokia AirScale Indoor Radio System enables an upgrade to 5G without replacing installed hardware, by attaching the radio heads directly to the AirScale smart hub and then daisy-chaining them with existing legacy pico radio heads. A new dual-port Ethernet extender allows the pico radio heads to be located up to 200m away from the smart hub.
They are also deployable on an existing DAS (Distributed Antenna System). A high level of output power – 4 x 250 mW – enables large coverage areas in sites such as shopping malls.
Another vendor which is positioning itself for mmWave deployment in the USA and elsewhere is Airspan, already a major supplier of indoor small cells to Sprint (the operator’s Magic Box). Airspan announced it was working with Qualcomm on 5G mmWave RAN platforms based on the latter’s FSM100xx 5G Platform.
Airspan says it has deployed almost 500,000 indoor and outdoor small cells worldwide based on the Qualcomm FSM99xx Small Cell Platform, and is now moving towards sub-6 GHz and mmWave 5G products, featuring technologies such as Massive MIMO and distributed virtualized RAN architectures.
Eli Leizerovitz, Airspan’s head of products, said: “Operators are looking for a variety of 5G solutions which will allow them deployment flexibility from ‘All-in-One’ to split 7. Airspan’s 5G solutions are designed in a modular way that allows support for all split architectures, for both outdoor and indoor use cases”.
But while the infrastructure may be maturing for mmWave, it is likely to be serving only limited numbers of users, in fixed wireless environments, for a while yet as engineers grapple with the issues of power consumption in mobile devices. At the recent International Solid State Circuits conference, this was a hot topic but most people agreed there was a long way to go still.
“Millimeter wave front ends will likely burn multiple watts — I don’t even want to buy the first 5G mmWave phased-array handset,” Benjamin Jann, a cellular RF engineer from Intel, told EETimes after presenting a paper on his company’s mmWave transceiver.