Simplifying antenna integration in a healthcare device with Virtual Antenna® Technology

Antenna integration can be complex and challenging, particularly in small form factors and devices requiring multiple frequency bands. However, advancements in Virtual Antenna® technology have greatly simplified this process. In this blog post, we will explore how Virtual Antenna® technology makes antenna integration easier and more efficient. We will also examine the specific challenges encountered in designing a blood pressure monitor for Withings and how these challenges were overcome using Ignion’s Oxion™ platform in conjunction with Virtual Antenna® technology.

When designing a device, one of the key considerations is meeting the performance requirements, particularly in terms of cellular connectivity. In the case of the Withings blood pressure monitor, there were a number of challenges. Withings was taking an existing product design, the BPM Connect which has a small, elegant design, and needed to add cellular to address a new use case for professional health providers and their patients who did not necessarily have access to a smartphone to use the Withings app. The small PCB size posed limitations on antenna performance, especially for cellular while the proximity of the antenna to the body caused signal degradation. These challenges needed to be addressed to ensure optimal antenna efficiency and a fast development schedule.

Virtual Antenna® technology offers a streamlined solution for simplifying antenna integration and optimizing performance. Using Ignion’s online design tool, Oxion™, engineers can input the frequency range and PCB size to receive tailored antenna recommendations, matching network requirements, and performance data. This tool allows engineers to evaluate antenna performance early in the design process, saving time, reducing effort, and minimizing risk.

For the Withings blood pressure monitor, the feasibility phase began with Oxion™ to assess antenna performance. Initial results showed that efficiency was relatively low due to the small PCB size. To address this, increasing the PCB size and implementing an active circuit topology were recommended, allowing the LTE bands to be fine-tuned for peak efficiency.

During the design phase, Withings’ engineers refined their PCB layout and integrated the antenna into the enclosure. Simulating the complete design revealed slight frequency detuning and an efficiency drop due to the enclosure and body interaction effects. The matching network was then adjusted to retune the frequency and optimize performance. Thanks to Virtual Antenna® technology, this process took only a week by simply adjusting the matching network—far faster than alternative antenna solutions that would require several weeks.

Once satisfied with the simulated performance, the engineers built the first prototype hardware. Physical tuning and optimization were conducted using a body phantom hand in Ignion’s Barcelona lab to simulate real-world conditions. Minor detuning was observed, but with the flexibility of the matching network, frequency adjustments were made easily, achieving optimal performance.

After the necessary optimizations, the Withings blood pressure monitor successfully achieved certifications and was market-ready. This design journey highlighted how Virtual Antenna® technology, together with the Oxion™ digital twin platform, simplified the antenna integration process. The Virtual Antenna® component enabled easy integration into the compact form factor while providing broadband and multi-band capabilities. This approach ensured consistent results and saved time throughout the design process. Remarkably, the product moved from concept to final design in under a year.

Virtual Antenna® technology offers a streamlined approach to antenna integration, enabling engineers to optimize performance and meet design requirements. The Oxion™ platform serves as a valuable resource for assessing antenna performance early in the design process. By utilizing Virtual Antenna® technology and following a structured design journey, engineers can simplify the integration process and achieve optimal antenna efficiency.

Leveraging the power of Virtual Antenna® technology with a customer-centric design approach, companies can simplify their antenna integration processes, save time, and bring high-performance IoT products to market efficiently.