Choosing a frequency band is a foundational decision that shapes the performance, safety and compliance of a wireless medical device. Whether you’re designing a wearable patient monitor, a portable diagnostic tool or a connected implant, the RF band you select will determine everything from signal reliability to regulatory approval.
Whilst medical devices are restricted to operating in regulated frequency bands, those bands vary in characteristics, usage rights and real-world behaviour. Selecting the right one means navigating a series of trade-offs between interference, range, data rate and compatibility with global standards. This article walks you through that process and helps you take the next step toward choosing the right antenna to match.
Start with spectrum - survey before you select
The best RF band for your device is shaped by where and how the device will be used. Performing a spectrum survey of your target environment is a crucial early step. Hospitals, for example, tend to be saturated with Wi-Fi, Bluetooth and other 2.4GHz devices. Meanwhile, in-home or remote care settings may experience less congestion but have different coverage requirements.
A spectrum survey helps identify which bands are heavily used, where interference might be problematic, and which frequencies are likely to provide the most reliable operation in your deployment context. This insight should inform your band selection.
ISM bands - globally available but crowded
The ISM (Industrial, Scientific, and Medical) bands, particularly 2.4 GHz and 5 GHz, are attractive because they’re license-free and globally accessible. Technologies like Wi-Fi, Bluetooth, Zigbee, and LoRa often operate in these bands, making integration with existing systems easier.
However, these advantages come with trade-offs. ISM bands are heavily congested, especially in hospital environments, which increases the risk of interference. Devices using these bands must be designed with robust coexistence strategies and highly efficient antennas to maintain performance under pressure.
Sub-GHz ISM bands - low power, longer range
Sub-GHz ISM frequencies, such as 433 MHz, 868 MHz (Europe), and 915 MHz (North America), are often used in low-power medical applications requiring longer range. These bands offer better signal propagation through walls and the human body, and are less congested than 2.4 GHz.
However, these benefits come at the cost of lower bandwidth, making them unsuitable for high-data-rate applications. They're ideal for wearable monitors, asset trackers, and devices that send small, infrequent data packets. Compliance also becomes more region-specific in sub-GHz, so devices may need variants for different markets.
Dedicated medical bands - clean but constrained
In some regions, frequency bands are reserved specifically for medical telemetry. For example, the Medical Implant Communication Service (MICS) band at 402–405 MHz in the U.S. is dedicated to ultra-low-power communication with implantable devices. These bands are tightly regulated, with strict limits on power and usage profiles to ensure safe operation in and around the human body.
The key advantage here is low interference: fewer competing devices make for cleaner signals. But designers are constrained by limited data rates and tight regulatory compliance. These bands are highly application-specific and often require careful antenna tuning to operate within extremely narrow spectral limits.
Cellular and LPWAN - wide area, connected care
Cellular bands, used in LTE-M, NB-IoT and legacy 2G/3G/4G systems enable medical devices to connect directly to cloud services without relying on local infrastructure. This is a major advantage for remote monitoring, emergency alerts and field diagnostics. LPWAN technologies like NB-IoT offer extended range, deep indoor penetration and exceptional power efficiency.
However, cellular adds complexity. Device certification becomes more rigorous, power management must be tightly controlled and antennas must support multi-band operation. Still, for devices that need wide-area coverage or autonomous connectivity, cellular is a strong option.
Matching the RF band to the right antenna
Once you’ve selected the most suitable frequency band (or combination of bands) the next decision is antenna selection. This is where trade-offs in form factor, performance and integration complexity come into play.
For example, if you’re designing for 2.4 GHz in a compact wearable, you’ll need a high-efficiency, miniature antenna that performs reliably in close proximity to the body. For sub-GHz applications, you may need a larger antenna footprint or use an FPC antenna that can be shaped to fit your enclosure. Multi-band cellular applications require antennas that operate across multiple frequency bands without excessive size or compromise in performance.
Choosing an antenna that is specifically tuned for your selected RF band and one that accounts for your enclosure, materials, body proximity and layout is the final step in delivering robust, reliable wireless performance.
Have confidence with your medical device connectivity
At Antenova, we specialise in antennas that support a wide range of frequency bands used in medical devices, from 2.4 GHz and sub-GHz ISM to LTE, NB-IoT and GNSS. Our antennas are engineered for performance in compact spaces and medically sensitive environments, and are available in surface-mount, flexible, and embedded formats to suit your design.
We also support device manufacturers with design integration, matching, and tuning to help you achieve compliance, pass certification, and bring your product to market faster.
If you’re ready to match your medical device to the right frequency band and antenna, download our guide below.
