Wireless Connectivity & IoT / UWB

UWB: Technology and Filter Requirements

UWB (Ultra-Wideband) is a short-range radio technology that, unlike narrowband systems, utilizes an extremely wide frequency spectrum, typically in the ranges from 6.0 GHz to 8.5 GHz (Channels 5 to 9). The technological foundation is the transmission of ultrashort pulses in the nanosecond range, enabling high-precision distance measurement (centimeter-level accuracy) and robust data transmission. Since UWB operates with a very low spectral power density below the noise floor of other radio services, protection against strong out-of-band signals such as 5G n78 (3.5 GHz) or Wi-Fi 6E (6 GHz) is the greatest challenge for RF hardware.

Wainwright Instruments provides specialized high-performance filters for these broadband applications, designed to stably support the wide passband of 500 MHz to over 1 GHz per channel while ensuring extremely steep rejection of neighboring cellular and Wi-Fi signals. To maintain the integrity of time-critical pulses and thus the accuracy of Time-of-Flight (ToF) measurements, these filters must exhibit excellent group delay stability. Our solutions prevent overloading of high-sensitivity UWB front-ends and ensure coexistence in complex multi-radio environments, which are standard in modern industrial and infrastructure applications.

Typical Deployment Scenarios:

UWB filters from Wainwright are crucial components in systems requiring absolute precision in localization and highest immunity to interference in a densely populated GHz spectrum.

• Automotive Keyless Entry: Within digital vehicle keys and anchor points in the car, our filters secure communication against relay attacks by eliminating disruptive RF signals that could falsify the ToF measurement.
• Industrial Real-Time Localization (RTLS): In smart factories, our filters ensure precise tracking of tools and AGVs to within a few centimeters, even in environments with massive metallic reflections and strong Wi-Fi networks.
• Consumer Electronics & Wearables: For near-field data transmission and finding objects (Find My Service), our filters protect UWB modules from saturation by strong external Wi-Fi 7 signals.
• Medical Technology (Patient Tracking): Within clinics, our RF solutions secure the localization of mobile medical devices in the 8 GHz range to guarantee rapid availability in emergency situations.
• Smart Home & Presence Detection: UWB sensors are used for fine-grained detection of people in a room; our filters prevent false triggering caused by neighboring 5G routers or microwave leaks.
• Logistics & Warehouse Management: In automated high-bay warehouses, our components effectively suppress signal interference in the 6.5 GHz range to ensure smooth coordination of autonomous picking robots.
• Secure Payment & Ticketing: For contactless payment with integrated distance measurement, our filters secure the transaction against manipulation by external RF jammers.
• Research & Development: For characterizing the impulse response of new UWB chipsets, we supply reference filters with minimal group delay distortion to validate the theoretical accuracy of the hardware under real-world conditions.

Suitable Filter Categories for Wireless Connectivity & IoT / UWB

The enormous bandwidth and high frequencies of UWB demand filter solutions that combine extraordinary broadband capability with extremely steep stopbands.

Band Pass Filters

Our UWB Band Pass filters enable precise selection of channels in the 6.0 GHz to 9.0 GHz range. They are specifically optimized for use in professional localization systems, combining wide passband bandwidth with extremely steep rejection skirts to neighboring Wi-Fi and cellular bands. By optimizing group delay, we ensure that the nanosecond pulses are not distorted, which is the basic requirement for centimeter-accurate localization. The mechanical precision of our resonators also guarantees minimal insertion loss across the entire utilized spectrum to conserve the tight link budget of UWB systems. Manufacturers of infrastructure components benefit from the high power handling and precision of our filters.

Manually Tunable Band Pass Filters

For the development of UWB antenna systems and the validation of localization algorithms, we offer manually tunable Band Pass filters covering the range from 5 GHz to 10 GHz. Via high-precision mechanical tuning elements, the passband can be adjusted exactly to specific UWB channels or experimental frequency ranges. This flexibility allows engineers to investigate the robustness of their systems against targeted broadband interference in the lab. The robust construction of our manually tunable filters guarantees permanent reproducibility of measurement results, which is essential for calibrating high-end localization systems.

Digitally Tunable Band Pass Filters

Electronically controllable filters support modern test environments and SDR systems that must react agilely to different UWB channels. Via digital interfaces such as SPI, filter parameters can be adjusted in real-time, which is particularly advantageous for automated test sequences checking channel selectivity. Our digitally tunable filters combine digital control precision with the necessary RF quality and are optimized for use in test environments and development systems. They enable rapid reconfiguration of test scenarios without manual intervention, supporting efficient quality assurance processes in the manufacturing of UWB modules.

Band Reject Filters / Notch Filters

Our UWB notch filters serve to eliminate specific strong interfering signals located within or immediately adjacent to the wide UWB spectrum, such as strong Wi-Fi 6E signals at 6.2 GHz. They feature extremely deep stopband attenuation while the rest of the wide UWB passband remains nearly unaffected. This protection is fundamental to prevent saturation of the high-sensitivity correlators in the UWB receiver. By using our notch filters, the robustness of the infrastructure against narrowband interferers is massively increased, significantly increasing the reliability of distance measurement in RF-burdened environments.

Manually Tunable Band Reject Filters / Notch Filters

Frequency-tunable notch filters provide a flexible solution for interference suppression directly in the field or during the commissioning of complex RTLS systems. By manually adjusting the stopband frequency, interfering signals caused, for example, by other industrial radio systems in the 6 GHz range can be masked immediately. This ensures localization accuracy without waiting for new filter hardware. The mechanical precision of our filters guarantees that once a stopband frequency is found, it remains stable over long periods, which is particularly decisive for permanently installed anchor points in factory halls.

Digitally Tunable Band Reject Filters / Notch Filters

In intelligent localization networks, digitally tunable notch filters enable an automated response to dynamic interference scenarios. Controlled by monitoring algorithms, these filters can dynamically mask interfering signals in real-time to maintain precision for critical applications such as human-machine collaboration. Their integration into automation concepts for radio optimization allows for autonomous radio optimization of entire production areas. Thanks to remote controllability, operators can adjust filter characteristics centrally, reducing operating costs and massively increasing the resilience of UWB anchors against new interference sources at shared mounting locations.

Monoplexer / Diplexer / Duplexer / Triplexer

Combining UWB with other radio standards like Wi-Fi 6E/7 or 5G on a shared antenna structure requires high-performance multiplexers with extremely high isolation. Our diplexers for 6 GHz separation enable simultaneous use of Wi-Fi and UWB with minimal mutual interference. Wainwright Instruments manufactures these components with a focus on minimal group delay distortion in the UWB branch so as not to impair localization accuracy. Precise tuning prevents signal crosstalk and protects sensitive UWB receiver paths in industrial anchors and gateways from overloading. Our multiplexers are optimized for use in professional localization systems and industrial infrastructure applications.

Absorptive Filters

Absorptive filters play a crucial role in the transmission infrastructure of UWB anchors and test transmitters to preserve the signal purity of ultrashort pulses. Rather than conducting unwanted harmonics or reflections back to the pulse generator, these filters safely convert them into heat, preventing pulse distortion (ringing). This is particularly important for complying with strict regulatory masks for spectral power density. Our absorptive filters are designed for continuous operation and increase the precision of time measurement by consistently minimizing thermal stress and signal reflections.