From Space to Anywhere: New Ka-Band Transceiver Promises to Connect Remote Areas

August 06, 2020 by Antonio Anzaldua Jr.

Socionext and Tokyo Tech have developed what they claim is the first Ka-band SATCOM transceiver that uses CMOS technology.

In many remote regions of the world, people can't simply jump on a Zoom meeting or browse social media because they don't have the internet coverage to do so. Now, however, there may be a way to connect to the internet via satellites transmitting signals from Earth's orbit. 


Ka-band satellite communications

Ka-band satellite communications (SATCOM) frequencies provide new opportunities to meet high bandwidth demands, especially for small aerial and mobile land platforms. Image used courtesy of Socionext


Socionext and researchers at the Tokyo Institute of Technology (Tokyo Tech) have developed a Ka-band transceiver for enabling seamless communication between earth ground platforms and satellites in the low, middle, and geostationary Earth orbits.

This advancement holds the promise of bringing the internet to remote locations, like rural areas or the open sea, that may otherwise be a dark zone for connectivity.


A Brief History of SATCOM

While many of us can easily access the internet because of nearby cell towers, we also frequently tap into technology that already relies on satellite communications, like global positioning systems (GPS). GPS beams information down from orbiting satellites using a special kind of transmitter (TX) and receiver (RX) to locate your device and generate a map for your travels.

Satellite communication (SATCOM) is used for television, telephone, radio, internet, and military applications. This method is an attractive option for providing data links to both well-connected and remote locations. But for SATCOM to be effective, the right equipment must exist both in space and here on Earth. 


The Appeal of the Ka-Band

For years, scientists at the Tokyo Institute of Technology have been developing various types of state-of-the-art transceivers for next-generation technology, including 5G applications, Internet of Things-enabled devices, and low-power Bluetooth communications. 

The SATCOM transceiver device that was developed in this study utilizes Ka-band frequency, a microwave part of the electromagnetic spectrum with the range of 27–31 GHz. The Ka-band is a desirable location in the spectrum since it is less congested compared to areas with thousands of satellites transmitting and receiving signals in other frequency ranges. 

NASA has gravitated toward the Ka-band in such designs for years, providing an overview of its Ka-band transceiver architecture in 2016: 


Ka-band transceiver design

Ka-band transceiver design, which includes an RF front end and a digital back end. Image used courtesy of NASA

In an article on three new ASICS for 5G, we discuss how one company, Ensilica, is also developing a Ka-band transceiver. Ensilica's specific design is geared to combine the SATCOM technology with 5G to connect vehicles on the road as well as marine and aerospace vehicles.


Tokyo Tech and Socionext Release a Ka-Band Transceiver

The Ka-band transceiver from Socionext and Tokyo Tech is unique in that it is implemented using standard CMOS technology.

It has a high-quality factor transformer to achieve efficient power use and high linearity in transmission, which results in lower distortion during transmission. On the receiver side, the device features a dual-channel architecture.


The goal is to have seamless communication with satellites that are close to 2,000 km away from a 3 mm by 3 mm chip

The goal is to have seamless communication with satellites that are close to 2,000 km away from a 3 mm by 3 mm chip. Image used courtesy of Socionext


These signals are received in parallel using either two independent polarization modes or two different frequencies. In addition, the proposed design can perform adjacent-channel interference cancellation. Any unwarranted signals received in one channel by another signal on an adjacent frequency band is eliminated using information received at the other channel.

This strategy increases the dynamic range of the system, thus allowing it to operate correctly even in less-than-ideal scenarios with stronger noise and interference. 


From Space to Anywhere in the World

This latest transceiver is a potential solution for widespread connectedness.

Professor Kenichi Okada at the Tokyo Institute of Technology expressed how his research team is making a statement with this new development: “Our paper presents the first Ka-band SATCOM transceiver implemented using standard CMOS technology and designed for an earth ground platform communication with geostationary and low Earth orbit satellites.” 

SATCOM can be found orbiting Earth around 200–2,000 km, which will make communication a challenge when sending Ka-band signals. Further developments in Ka-band transceiver technology may very well launch us closer to the geostationary region.