Case study

Developing a 5G NTN handset antenna for the Sat Companion

Terrestar Solutions

Terrestar Solutions partnered with TTP and Bittium to develop the Sat Companion, a device that unlocks direct-to-mobile 5G NTN services, compatible with all smartphones. As part of this project, TTP had to develop a new high-gain antenna system that met strict regulatory requirements for Specific Absorption Rate (SAR), ensuring safe levels of power absorption by the human body.

Context

Terrestar Solutions Inc., a Canadian satellite operator, partnered with TTP and Bittium to develop the “Sat Companion”, a snap-on device that enables 5G NTN GEO satellite connectivity for standard mobile phones. A key challenge to GEO connections from handsets is providing enough radio frequency (RF) power to achieve a reliable link, whilst also maintaining a SAR level within regulatory limits.

Solution

TTP designed a novel antenna system to meet Terrestar’s link requirements by leveraging rigorous electromagnetic simulations and testing to achieve high gain and high power with minimal SAR. These performance gains were partly enabled by cutting-edge meta material structures that lower SAR exposure at the user’s head.

Result

A patent-pending, high-gain NTN antenna solution for the Sat Companion, enabling uninterrupted SMS, chat, voice, and email services for users on their own mobile phones, even in the most remote locations.

Bringing direct-to-device satcoms to everyone, everywhere

Terrestar Solutions Inc. are engaged in the race to bring direct-to-mobile satellite services to smartphones and IoT devices and make anywhere-in-Canada communication a reality. To accelerate the availability of direct-to-mobile phone satellite communications, Terrestar partnered with Bittium and TTP plc to develop a next-generation device – the Sat Companion. Initially, Terrestar are focused on demonstrating 5G NTN services across Canada via the Echostar T1 GEO satellite. By integrating messaging and voice over NB-IoT through Terrestar’s mobile sat app , the Sat Companion will ensure seamless on-the-go connectivity.

"Developing the Sat Companion required groundbreaking innovation in antenna design. TTP engineered a high-gain antenna system that not only enables direct-to-mobile 5G NTN connectivity but also meets the most stringent SAR regulations, ensuring both performance and user safety. This achievement marks a significant step forward in making seamless global communication a reality."

Serge Legris, Eng., CTO, Terrestar Solutions Inc.
No items found.

Our approach

‍01

High gain and low-SAR

Due to their distance from Earth and position in the sky relative to a handset user, reliable GEO satellite links demand higher handset RF power towards the satellite. However, increasing power typically raises SAR, which is a measure of the rate at which energy is absorbed per unit mass by a human body when exposed to a radio frequency (RF) electromagnetic field. TTP was tasked with developing an antenna that could achieve both high power and high skyward antenna gain while keeping SAR levels within strict North American regulatory limits, which are more stringent than those in Europe.

02

Understanding surface waves

Surface waves play a crucial role in how electromagnetic fields interact with the human body, influencing both signal efficiency and user safety. In satellite communications, managing these waves is essential to balancing antenna performance with SAR limits. Higher frequencies tend to create surface currents that stay mostly on the skin, while lower frequencies penetrate deeper into tissue. For the Sat Companion’s 5G NTN antenna, optimizing surface wave behaviour was key to achieving strong connectivity without exceeding regulatory SAR thresholds.

03

Verified and validated through real-world testing

To find a solution for the antenna which could offer a small enough form factor, high enough gain and lower SAR, TTP examined a variety of antenna types and geometries, all of which had to fit within a typical mobile device. To aid in this, high impedance surfaces (HIS) were also placed near the antenna structures to reduce SAR.

This process involved intensive electromagnetic simulations in CST software suite. The process started with the optimisation and tuning of the various designs, followed by modelling that incorporated the user’s full head and hand and phone, providing true gain and maximum SAR level.

The models were then verified and validated through real-world testing in TTP’s anechoic chamber, which included the use of a phantom head and hand to fine-tune the solution for this demanding application.

In the end, an antenna that utilises novel meta-material structures to help reduce surface waves, leading to lower SAR whilst also increasing gain from the antenna was chosen.

To conclude, TTP’s simulations and real-world testing demonstrate that the chosen antenna design is pragmatic and capable of meeting stringent criteria such as link budget, SAR, and form-factor considerations.

Sat CompanionTM is a trademark of Terrestar Solutions Inc.

Learn more about Sat Companion here or read our press release.

‍

Sat Companion prototype will be showcased at:
MWC 2025 – Hall 5, Stand 5J45
Satellite 2025 – booth #2437‍

‍‍

Meet some of the team

Talk to us about your next project

We help clients with all stages of their most complex and challenging technology and product development projects.

If you're considering the next steps along your innovation journey, why not get in touch?

Get in touch

Talk to us about your next project

Whether you would like to discuss a project or would like to learn more about our work, get in touch through the form below.

Meet some of the team

You might also like

Case Studies
TTP’s low-cost electronically steerable antenna for Satcom user terminals
Satellite terminals
Aviation satcoms
5G non-terrestrial networks
Case Studies
Working with Ofcom to understand resilience of wireless receivers to interference
5G non-terrestrial networks
Case Studies
Omnispace teams with TTP to expand 5G development partner ecosystem
5G non-terrestrial networks

Get the latest from TTP

Join our community to get the latest news and updates on our work at TTP.

You will occasionally receive expert insights from across our areas of focus and hear directly from our engineers and scientists on the newest developments in the field.

Subscribe

Get the latest from TTP

Join our community to get the latest news and updates on our work at TTP.

No items found.