Fujitsu unveils small cell mmWave 5G tech

Fujitsu Laboratories has announced developing a millimetre-wave (mmWave) phase shifter for small cells, which it said delivers the 10Gbps connections required by 5G while maintaining low power usage.

Fujitsu has been working on combining small cells and beam forming for over a year; however, the company had previously been stuck on developing phase shifter circuits with half the power consumption of circuits.

The new tech has reduced power consumption down to just 3W.

According to Fujitsu, its new phase shifters have reduced the number of amps needed by combining switching circuits with differential amps; and using a new mmWave circuit has limited the electrical loss of circuits.

“Phase shifters are circuits that determine the direction of the beam output from an antenna array by adjusting the phase of the input signal to each antenna in a range of 0 to 360 degrees. Up until now, each phase shifter has required four amps,” it explained.

“Now, by developing a new switch circuit that can switch the phase of the output signal to 0 and 180 degrees, or 90 and 270 degrees through encoding a positive or negative sign into the input signal, Fujitsu Laboratories has successfully reduced the number of required amps to two.”

While the company said mmWave spectrum provides the high speeds necessary for 5G, it added that millimetre waves are “very one-directional”. As such, its new small cell technology makes use of beam-forming, with Fujitsu saying it controls 128 antenna elements.

Fujitsu has also added the capability to measure the phase and amplitude set by the phase shifter and adjust to compensate for deviation, further decreasing power consumption and increasing the accuracy of beam directions.

Such 5G small cells — which are effectively miniature base stations — could be deployed in areas with high-density populations, including train stations and stadiums, Fujitsu said.

“In places with a high concentration of people, it is envisaged that the use of a method called small cells, in which base stations are deployed every few tens of metres, will be called for,” it said.

“These base stations will require technology that can handle communications with multiple users simultaneously by dividing and multiplexing beams using a technology called beam-forming, which uses multiple antenna elements to concentrate the signal in a desired direction.”

Fujitsu said it will next look to conduct field trials and develop equipment ahead of offering a 5G small cell product by 2020.

Fujitsu has been working on 5G trials with NTT DoCoMo in Japan since 2014, in addition to being involved in the United Kingdom’s 5G Innovation Centre (5GIC).

Small cell technology has been a major focus for carriers and networking companies globally, with Ericsson in August similarly unveiling three new small cell solutions that it said will help prepare networks for the launch of 5G by extending coverage and capacity using LTE/5G tight interworking.

The networking giant labelled its new small cell solutions, which will be commercially available in 2018, the Multi-Operator Dot and the Multi-Dot Enclosure for indoor deployments, and the Strand-Mount Unit for outdoor micro radios.

Nokia has also been upgrading its small cell technology, in June unveiling a new way of deploying small cells in a bid to support telecommunications providers in building out additional mobile coverage within a shorter timeframe.

The practice provides a predictable, low-cost, “highly repeatable” site solution for rolling out small cells within 16 weeks from planning to completion — significantly reducing the 12- to 18-month timeframe previously experienced by telcos in rolling out macro cells.

Optus and Telstra have been deploying small cells to increase the density of their metro networks, provide data and voice coverage for regional areas, and as part of their obligations under the Australian government’s mobile blackspot program.

Under round one of the blackspots program, Telstra will deploy 135 small cells using its own funding, while Optus will be providing 49 small cells under round two.

Singaporean telecommunications provider M1 last year also commercially launched a nationwide heterogeneous network using small cells with Nokia, while Ericsson worked with Singtel on a live trial of indoor small cells in July 2016.

Use of the mmWave band for 5G services is also currently being examined across the globe, with the Australian Communications and Media Authority (ACMA) last month announcing a proposal to accelerate the decision-making process after hearing of “urgency” around setting aside 5G spectrum.

The ACMA said international standards and harmonisation are “progressing rapidly”, with the mmWave band possibly to be in use prior to 2020. It is now looking to “streamline” the early consideration of the 26GHz band, which includes 24.25-27.5GHz spectrum, as well as “potentially other mmWave bands”.

Telcos are already looking to use mmWave spectrum for 5G, with Telstra in February announcing a series of 5G new radio (NR) trials across Australia with Ericsson and Qualcomm.

The trials will use mmWave spectrum technologies to increase network capacity and allow for multi-gigabit speeds, as well as Multiple-Input Multiple-Output (MIMO) antenna technology along with beam forming and beam tracking.

Ericsson and IBM earlier this year also announced a “research breakthrough” in 5G, saying a new silicon-based mmWave phased array integrated circuit could accelerate 5G uptake.

According to Ericsson and IBM, mmWave bands allow for speeds that are more than 10 times faster than the frequencies used currently for mobile devices.

Also working on 5G mmWave products and solutions under the assumption that they will be deployed globally are Intel, Samsung, Huawei, Qualcomm, ZTE, and Nokia.