Millimeter wavelengths (mmWave) for data transfer, at play in radio telescopes and communication satellites, have long been viewed as pie-in-the-sky regarding terrestrial applications such as cell phones and self-driving cars due to the need for unobstructed paths between sender and receiver.
The expansion of frequencies out to 100 gigahertz (GHz) – squarely within the mmWave band of 30Ghz to 300GHz – as part of the pending introduction of 5G communications has been considered unworkable for hand-held devices: the interference and attenuation that can occur when those transmissions encounter commonplace objects, anything from a brick wall to falling rain, have stalled the introduction.
Efforts by California semiconductor giant Qualcomm, whose chipset and modem designs facilitate data transmissions in everything from smartphones to supercomputers, are deploying a variety of techniques – both on-device and on cell towers – to beam mmWave transmissions around corners and around the world.
In the process, the company is liberating the higher end of the frequency spectrum for hand-held device deployment and the flow of richer packets of data ahead of the launch of 5G, which is expected to begin in the US and other developed markets in 2020.
Qualcomm’s recent watershed announcement revealed it had devised a transceiver module for its Snapdragon modem that embraces mmWave frequencies and put it to work in smartphone applications.
Coupled with a sub-6GHz module, Qualcomm has the full range of coverage for 5G, and is committed to expanding the number of connected devices above 20 billion for personal and enterprise use that comprise the Internet of Things (IoT).
The company has built on the Snapdragon X50 modem, launched in October 2016. Work to integrate the Snapdragon X50 within an antennae construction for handheld devices started shortly after its introduction, with prototyping and testing taking place with customers over the ensuing 22 months.
Competitors, namely China’s Huawei, have introduced full-spectrum capability for base stations and small-cell broadcast points. However, the company – a Qualcomm customer – has yet to offer a 5G-ready smartphone.
Rather than limited by line-of-sight paths between last-mile transmission points such as cell towers and nearby buildings, mmWave IoT devices can send and receive the gigabit-per-second transmissions that higher frequencies permit, including high-definition video and richly detailed virtual and augmented-reality environments.
All this can be done without the disruption that occurs when signals encounter fixed and moving objects, get degraded by atmospheric conditions or fall prey to “cross-talk” that occurs when transmissions are made at nearby frequencies.
The trick involves arrays of antennae placed on devices and the forming and triangulating of beams of data aimed at mobile transceivers from multiple base stations (including towers and small-cell routers) to facilitate massive Multi-Input, Multi-Output (MIMO) transmissions.
Personalizing Broadcast Range
Unlike the omnidirectional LTE (Long-term Evolution) broadcast technology on which 4G is based, massive MIMO’s so-called New Radio interface uses algorithms in tandem with tightly clustered base-station transmitters to locate and focus mmWave transmissions. Fundamentally, it is a purpose-built technology that covers the broadcast range between sender and receiver.
As a result, instead of limiting terrestrial mmWave applications to such unobstructed facilities as open-plan offices, sports stadiums and factory floors, the combination of technologies increases throughput and helps to alleviate capacity issues that have arisen as 4G’s 2GHz-8GHz spectrum has become increasingly overburdened.
Using mmWave can increase backhaul capacity, allowing the expansion of point-to-point and point-to-multi-point transmission arrays for greater flows of data over wireless personal and local-area networks.
It also can be applied in tracking and monitoring of fleets of networked vehicles, and in the datacenter, where links can be formed among different geographic locations without the use (and cost) of fiberoptic cabling.
For mobile devices, Qualcomm claims its mmWave and sub-6GHz antenna modules feature integrated power-management circuits and radio-frequency components that can deliver up to 800MHz of bandwidth. That means lower latency in transmissions, opening the technology up to applications in autonomous drones and self-driving vehicles, as well as AR and VR.
Qualcomm reports that the 5G modules are currently being put through their paces in applications with customers, and that the range of use-cases should grow when the modules become available on smartphones and other IoT devices in the coming year.