OneFiltr delivers YIG-sphere-level performance in a compact, power-efficient form—ideal for size-, weight-, and power-limited platforms. Designed for defense, satellite communications, test equipment, and more, it offers low insertion loss, sharp selectivity, and broad tuning range in a compact, agile, and power-efficient form.

Wideband Receiver

Satellite

Communication

Test Instrumentation

Defense

Wideband Receiver

Example: Tunable filter in Direct Sampling Receiver

Direct sampling receivers simplify RF systems by reducing cost, size, and complexity—especially in wideband, high-channel-density applications. Eliminating analog downconversion improves power efficiency, eases synchronization, and enables more compact designs. However, wideband ADCs have limited input voltage swing and lower dynamic range than narrowband ADCs. This significantly increases the demand for high-performance, compact filters.

OneFiltr meets these challenges head-on:

• High Selectivity with Low Loss: With >50 dB out-of-band rejection and low insertion loss, OneFiltr protects wideband ADCs from overload and noise, preserving dynamic range and signal integrity.

• Wideband Tunability: It continuously tunes from below 1 GHz up to 18 GHz and beyond, matching the frequency coverage of YIG sphere filters while avoiding the limitations of switched filter banks with limited freqencis channels selections.

• Compact & Efficient: Unlike bulky YIG sphere filters, OneFiltr delivers YIG sphere-like performance in a smaller, lighter, and more power-efficient form—ideal for systems with strict SWaP and cost constraints.

• Optimized Bandwidth: Tunable bandwidths from 50 MHz to 300 MHz offer strong adjacent channel rejection and better selectivity than ASIC-based filters, which often exceed 1 GHz in bandwidth.

For compact, wideband direct sampling systems, OneFiltr is the filtering solution that traditional technologies can’t match.

Reference:

National Instruments Corps, Advantages of Direct RF Sampling Architectures, Updated Nov 22, 2024

Peter Matthews, Filters in Radar Receivers, Posted on Mar 27, 2024

Satellite Communications

OneFiltr delivers agile, high-performance RF filtering tailored for next-generation satellite communication (SatCom) systems. Its compact, zero static power design suits size- and weight-constrained platforms like LEO satellites and mobile terminals. With reconfigurable filtering, satellite operators can dynamically switch frequency bands and operating modes during missions.

Beyond filtering, OneFiltr can be reconfigured into tunable phase shifters. This capability supports beam-steering and beam-forming antennas, which are crucial for applications such as establishing uplink connections from Low Earth Orbit (LEO) satellites to Geostationary Orbit (GEO) relay satellites.

OneFiltr's reconfigurable nature not only allows for adaptation to various communication scenarios but also significantly reduces system complexity and size. This results in lightweight and energy-efficient components, which are highly sought after by satellite operators.

Reference:

Maune, Holger, et al. "Tunable microwave component technologies for SatCom-platforms." Frequenz 71.3-4 (2017): 129-142.

Test Instrumentation

Example #1: Preselector in Spectrum Analyzer

Microwave spectrum analyzers often use a tunable YIG sphere-based preselector at the front end. Mixing the input with a local oscillator converts it to an intermediate frequency, but also risks letting in spurious signals like mixer images and LO harmonics. Preselectors only allow a narrow band of frequencies centered around the desired signal to reach the mixer, effectively rejecting out-of-band signals. Typical preselector bandwidths range from 35 MHz to 80 MHz—narrow enough to isolate desired signals while blocking adjacent interference.

The preselector offers several key benefits:

Improved Dynamic Range: By rejecting strong out-of-band signals, the preselector reduces distortion and prevents mixer overload.
Suppression of Spurious Responses: The preselector eliminates image responses and multiple mixing modes, which would otherwise result in misleading or duplicated signals on the display.
Simplified Operation: With reduced spurious responses, users can interpret results more easily without post-processing or second-guessing signal origins.
Better Performance Across Wide Frequency Spans: As it tracks the LO across a wide tuning range, the preselector helps maintain consistent performance.

Despite its advantages, current preselectors have some limitations:

Insertion Loss: Typically between 6–8 dB, this loss occurs before the first amplifier stage, directly degrading the system’s noise performance.
Passband Ripple and Mismatch: The preselector’s passband is not perfectly flat and can exhibit ripple. Impedance mismatches between the preselector and mixer may further degrade frequency response.
Slow Switching Time: Tuning and stabilizing the commericial YIG sphere tunable filter can take several milliseconds (typical 2 miliseconds per 1 GHz step to within +/- 10 MHz), which can slow down sweep speeds and affect measurement throughput.

OneFiltr aims to improve preselector performance by addressing these challenges. It also offers enhanced RF performance, including lower insertion loss, reduced passband ripple, and ultra-fast switching time under 1 ms (maximum of 100 microseconds from 3 GHz to 18 GHz). In addition, OneFiltr delivers these improvements in a smaller, lighter, and more cost-effective package—all while consuming no static power.

Block diagram of a high frequency superheterodyne spectrum analyzer

Reference:

[1] Keysight Technologies, X-series Signal Analyzers Preselector Tuning for Amplitude Accuracy in Microwave Spectrum Analysis.

[2] Keysight Technologies, Spectrum Analysis Basics, AN150.

Example #2: Oscillator in Signal Generators

YIG sphere oscillators have long been valued in frequency synthesizer design for their wide tuning range, low phase noise (typically –120 to –130 dBc/Hz at 100 kHz offset over 2–10 GHz), and highly linear, repeatable tuning characteristics. These advantages made them ideal for multi-loop synthesizer architectures and ensured their dominance in microwave systems for decades. However, YIG spheres are large, power-hungry, expensive, and slow—often taking milliseconds to tune.

OneFiltr has adopted a planar YIG structure that leverages magnetostatic wave (MSW) propagation in an epitaxial YIG film. Unlike the precision alignment required for YIG spheres within a magnetic bias field, planar YIG structures known for offering several compelling advantages:

Higher Q factor: Planar resonators have demonstrated loaded Q values up to five times higher than traditional YIG spheres (>1000 vs. ~200), improving frequency selectivity and phase noise.
Lower magnetic field requirements: For a given frequency, planar structures require less magnetic field strength to achieve resonance.
Compatibility with large scale manufacturing processes: These structures are compatible with standard microwave integrated circuit fabrication, enabling scalable and potentially lower-cost production. The planar YIG structure also does not require the complicated alignment of the YIG sphere.

Challenges of traditional planar YIG structures:

Larger footprint: Planar devices (e.g., ~3×25 mm) are physically larger than the 0.5–1 mm YIG spheres, complicating magnet design and limiting miniaturization.
Temperature sensitivity: Planar YIG structures are more susceptible to temperature variation. While stabilization methods like ovenization are well-established for YIG spheres, they are still being optimized for planar implementations.

OneFiltr’s innovation addresses these challenges while maximizing the benefits. By utilizing a planar YIG structure, OneFiltr achieves high quality factor superior phase noise performance potential. Its proprietary zero-static-power magnetic biasing circuit significantly reduces system bulk, cost, and power consumption traditionally associated with YIG-based designs. Furthermore, the use of small inductors in the magnetic coil greatly improves tuning speed. OneFiltr is also actively developing solutions to enhance temperature stability, ensuring robust, high-performance operation across diverse environments.

Reference:

[1] Chenakin, Alexander. "Frequency synthesis: current solutions and new trends." Microwave journal 50.5 (2007): 256.

[2] Carter, R. L., J. M. Owens, and D. K. De. "Yig oscillators: Is a planar geometry better?(short papers)." IEEE transactions on microwave theory and techniques 32.12 (2003): 1671-1674.

Defense

Example: Tunable Notch Filter for Radar Systems

The RF spectrum is becoming increasingly congested as more users. This rising interference can lead to saturation of the radar's low-noise amplifier (LNA), causing nonlinear distortions, signal corruption, and reduced signal-to-interference-plus-noise ratio (SINR), ultimately degrading radar performance.

A tunable notch filter (TNF) offers a dynamic and targeted approach. It can adapt in real time to block only high-power interferers, preserving the radar’s passband and protecting the LNA from overload. Positioned between the receive antenna and the LNA, a TNF helps maintain radar sensitivity and dynamic range, even in rapidly changing spectral environments.

OneFiltr functions as a tunable notch filter by using destructive interference to dissipate interfering signals at the notch frequency into a YIG resonator. Compared to commercial YIG sphere-based tunable notch filters, it offers several key advantages:

Ultra-fast tuning: Switches in under 1 ms—typically within 100 μs across 3–18 GHz—whereas commercial YIG spheres can take several milliseconds (about 2 ms per GHz) to stabilize within ±10 MHz.
Wider frequency coverage: Operates beyond the Ka-band, up to 40 GHz and higher.
Lower insertion loss: Achieves better RF performance while reducing insertion loss below that of YIG sphere filters, which typically reach up to 3 dB due to metal-rod transmission line limitations.

For OneFiltr’s application in direct sampling radar receiver, please refer to section wideband receiver, where a similar direct sampling technique is discussed.

Block diagram of a radar receive chain with a tunable notch filter (TNF).

Reference:

Roessler, Justin, et al. "Overview of tunable notch filters for radar systems." 2024 IEEE Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS). IEEE, 2024.

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