Interview with Jukka Sjöstedt from Radientum

  • Jukka Sjöstedt - CEO

We recently had a chance to interview Jukka Sjöstedt, the CEO of Radientum – a leading RF antenna design company. Radientum is an antenna design company. They help customers develop superior antenna solutions for wireless products. With the expertise of design, simulation and testing from Nokia & Microsoft, their engineers can develop antennas from the very first concept innovation through Over-The-Air verification to ready-made prototypes.

Mr. Sjöstedt, has 17 years’ of experience in the telecommunication industry and has previously worked in several management positions at Nokia and Microsoft. In the interview, he has shared highlights of the company’s current lineup of various design and test solutions and technologies as well as Radientum’s view of the future.

Q. Can you give us a brief history of Radientum? When was the company founded and what was the objective behind it?

Jukka Sjöstedt: Radientum was founded in 2015 by Nokia/Microsoft engineers with more than 20 years of experience in antennas & RF. We are utilizing our experience and skills in antenna development to help companies of all sizes to develop customized antenna solutions for wireless devices and systems in various industries. Our mission is “Bring optimal wireless performance to your device!”

Q. What services do you provide?

Jukka Sjöstedt: Radientum specializes in antenna & RF development services. We provide:

  • Custom antenna design and implementation
  • Consultation on choosing and implementing off-the-shelf antennas and wireless technologies
  • Antenna integration and performance optimization
  • OTA performance testing, measurement, and verification
  • Dielectric RF material measurement
  • EMC design and problem solving: Signal and Power integrity simulations

Q. Can you tell us more about your antenna design and development process - from start to finish? 

Jukka Sjöstedt: A typical antenna project involves 3 phases: Antenna concepting, Detailed Design and Implementation, and Performance verification in an anechoic chamber.

Antenna concepting at Radientum is primarily based on advanced simulation method with CST Microwave Studio software. Our accumulated expertise in antenna simulation can help companies reduce prototyping rounds and achieve optimal wireless performance in real environments. The project timeline varies depending on the complexity of the device/system and target performance level. It could take a couple of days or may take several months.

Q. At what stage of the product development process should customers come to you?

Jukka Sjöstedt:  Antenna should be considered in early stage of any wireless product development. So, right from the start is the ideal timing to ensure optimal wireless performance of your product. Antenna placement has biggest impact on device wireless performance and that is typically decided in very early of product development process.

Q. What types of products have you designed antennas for? Can you give us a few examples?

Jukka Sjöstedt: Radientum has worked on a wide range of products in various industries. Some examples are: smartphones, smart watches, wearables (rings, bracelets, TWS headsets), asset tracking devices, animal trackers, EV charging, payment terminals, smart home devices, positioning systems, IoT sensors, antenna arrays, and IoT devices for different industrial applications.

Q. Can you tell us about an interesting or challenging antenna design you have done recently?

Jukka Sjöstedt: We recently designed a panel antenna array system covering 70 MHz to 18 GHz, containing multiple antenna arrays. This was challenging because of the extreme bandwidth requirement, due to which we had to combine multiple antenna design and testing approaches in a single device, so as to ensure all antenna arrays worked properly without interfering with each other and with a good beam width.

Another example is wearable devices, where the body has a negative effect on antenna performance, not to mention the space constraints of these types of devices. Radientum has always delivered the best antenna solutions that go beyond customers' expectation.

Q. What are some antenna design challenges for Wearable Devices and 5G?

Jukka Sjöstedt: In wearable designs major challenges are dealing with body effects and extreme compactness. The antenna truly is a whole device and every part is affecting its wireless performance. 5G FR1 brings set of new frequency bands, requiring more antennas and broader bandwidth coverage. 5G FR2 mmWave bands call for controllable antenna patterns with high peak gain, which may be difficult to arrange in complex mechanical environments of consumer devices.

Q. What market/industry segments do you target or which Industry segments drive the most business for you?

Jukka Sjöstedt: Radientum is currently providing antenna & RF engineering services to customers in more than 20 countries worldwide. No matter what your industry is, we are able to help you if your challenges are related to wireless connectivity. Our customers’ industries are for examples: Consumer Electronics, Logistics, Wearables, Medical Devices, Telematics, Utilities, Automotive, and Telecommunications. We have seen increasing demand in many sectors, like IoT sensors, due to change from wired sensors into wireless sensors.

Q. What type of Over the Air (OTA) Measurements can you carry out for customers in your lab?

Jukka Sjöstedt: Currently our laboratory supports the following R&D OTA measurements:

  • Cable (passive) measurement 400 MHz - 6 GHz: 3D radiation pattern, antenna gain, efficiency
  • Constant wave power measurement 400 MHz - 6 GHz, TRP, EIRP-measurement
  • Active measurements: 2.4/5 GHz WIFI TRP & TIS and Cellular 2G, 3G, 4G, 5G TRP & TIS
  • UHF RFID tag performance testing including ARC/TIPP
  • We also have external labs at our disposal which allow testing devices at extended frequency ranges above 6 GHz and below 400 MHz.

Q. What type of Antenna Verification tests do you conduct?

Jukka Sjöstedt: Radientum provide both active and passive antenna verification. For passive measurements with cable, we can measure Return loss, Antenna efficiency, Radiation pattern (2D, 3D). For active measurements, we can measure, Total Radiated Power, TRP, Total Isotropic Sensitivity, TIS.

Q. Where are your customers located? Do you mainly work with customers in Europe or in other continents as well?

Jukka Sjöstedt: Radientum is currently providing antenna & RF engineering services to customers in more than 20 countries worldwide in Europe, North America, Asia, and Australia. 60% of our revenue comes from international markets. No matter where the customer is located, we can provide our customers world-class engineering support and services.

Q. What differentiates you from other antenna design companies?

Jukka Sjöstedt: We have more than 20 years of hands-on experience in antenna simulation, design, and testing based on more than 30 mobile phone models design in the past. In addition to this we have an agile and responsive start-up like way of working. We don’t only integrate antennas. We create device specific designs to get optimal performance or antenna size.

We have extensive experience with integrated PCB antennas in challenging use cases and design for mass production. Also have, extensive experience with antennas highly integrated in mechanics

Q. What is the 5 year roadmap for Radientum?

Jukka Sjöstedt: In the next five years, Radientum is aiming to be a name that is globally recognized when it comes to custom antenna design expertise. Radientum is the name to go to when companies face challenges with their wireless connectivity.  Our current development of 5G mmWave antennas will be ready to implement to particular customers' applications on the handsets and mobile devices.