Taoglas introduces configurable anti-jam GNSS reference design

Taoglas has introduced a controlled reception pattern antenna reference design intended to support development of GNSS receivers capable of maintaining positioning and timing performance in environments affected by radio-frequency interference.

The design combines four multiband antenna elements with RF front-end modules and supporting circuitry, providing a configurable hardware platform for evaluating interference suppression techniques. Taoglas is making the PCB layouts, component information, and mechanical design resources available to equipment developers building application-specific systems.

Introduced on 10 November 2026, the reference design supports satellite navigation applications involving aerospace, maritime equipment, autonomous platforms, precision agriculture, industrial infrastructure, and other systems dependent on reliable positioning or timing information.

Satellite navigation signals arrive at receiving antennas with extremely low power levels. Although receivers use sophisticated signal processing to recover the information transmitted by satellites, nearby radio-frequency emissions can interfere with that process when their received power becomes sufficiently strong.

Interference may originate from electrical equipment, communication transmitters, or deliberate jamming devices. It becomes particularly difficult to address when the unwanted transmission occupies the same frequency range as legitimate navigation signals.

Conventional filtering can attenuate signals outside the required frequency bands, but it cannot necessarily distinguish between a satellite transmission and an interfering signal arriving at a similar frequency. A controlled reception pattern antenna, or CRPA, uses spatial information to provide another means of separating wanted and unwanted signals.

The arrangement combines several antenna elements positioned at different locations within an array. Because a radio signal reaches each element with a different phase relationship according to its direction of arrival, the receiver can use those differences to alter its effective sensitivity across the surrounding environment.

Adjusting the amplitude and phase weighting applied to individual elements allows the complete antenna system to form directional nulls towards sources of interference. The same processing can maintain sensitivity towards satellite signals arriving from other directions, although the effectiveness of this approach depends on the available array elements and processing capabilities.

Taoglas's reference architecture uses four antenna elements. In principle, this configuration can support up to three independent spatial nulls, allowing the system to reduce sensitivity towards several interference directions simultaneously.

The figure represents a theoretical capability rather than guaranteed suppression of three interferers under every operating condition. Actual results depend on the relative directions of the signals, antenna geometry, calibration accuracy, element isolation, and the signal processing system connected to the array.

Taoglas provides configurations covering L1/L5, L1/L2, and L1/L2/L5 GNSS reception. The L1/L5 arrangement uses the company's GVLB258.A antenna, the L1/L2 design uses its HP2258.A, and the three-band version incorporates the HP25258.A.

The selected antenna elements are combined with TFM.110A multiband GNSS RF front-end modules and supporting electronics. The configurations address satellite systems including GPS, Galileo, GLONASS, and BeiDou, according to the frequency coverage of the chosen design.

The RF front end forms part of the signal acquisition chain, preparing the received signals for the subsequent processing needed to implement adaptive interference suppression. The reference board alone does not constitute a complete GNSS receiver or provide all the processing functions required for a finished anti-jamming system.

Antenna spacing creates an important design trade-off. Elements placed closer together reduce the overall size of the array, but can experience stronger mutual coupling, with energy from one antenna influencing the behaviour of its neighbours.

Such coupling changes the phase and amplitude relationships on which spatial processing depends. It can therefore reduce the accuracy with which the receiver estimates signal arrival directions unless the effects are appropriately characterised and included in the system calibration.

Increasing the size of the array can improve spatial separation under some conditions, but introduces a larger mechanical footprint. The required dimensions will depend on the intended frequency bands, available installation space, and the interference conditions the system must withstand.

Taoglas offers three PCB sizes of 110 mm, 150 mm, and 170 mm. The company identifies the 150 mm, two-by-two layout as its recommended baseline, while the larger 170 mm arrangement provides an alternative where physical space permits additional antenna separation.

Each supported frequency configuration is accompanied by downloadable Altium PCB design files, three-dimensional mechanical models, and two-dimensional drawings. These resources provide a defined starting point for adapting the antenna arrangement to the mechanical and electronic requirements of individual equipment designs.

The PCB layout must also manage RF isolation. Ground-plane geometry, feed routing, via arrangements, and the placement of surrounding components can affect the antenna characteristics, making it necessary to evaluate any modifications to the reference layout.

Phase-centre stability presents another consideration. The effective reception point of an antenna may change with signal arrival direction and frequency, introducing errors into measurements that rely on precise satellite ranging.

Changes to antenna geometry or nearby mechanical structures can affect this behaviour, particularly when the installation includes a conductive enclosure, mounting surface, or other materials capable of altering the RF environment. The reference design therefore requires evaluation within the intended final assembly.

Multipath interference creates a related measurement problem. Satellite signals reflected by buildings, vehicles, and other surfaces can arrive from different directions with altered timing and phase relationships, reducing positioning accuracy even where no deliberate jammer is present.

Spatial filtering can reduce sensitivity towards some reflected signal directions, providing another potential benefit beyond suppressing high-power interference. The achievable improvement will depend on the geometry of the environment and the receiver's ability to distinguish the relevant signal paths.

Jamming and spoofing must nevertheless be treated as different threats. Directional suppression can attenuate an unwanted signal arriving from an identifiable direction, but it does not establish that a receiver can authenticate satellite information or detect every deliberately manipulated navigation signal.

Receiver-level integrity functions, signal processing, and appropriate validation may therefore remain necessary where equipment must operate in a hostile electromagnetic environment. The effectiveness of the complete system cannot be inferred solely from the number of antenna elements.

Taoglas is presenting the design at electronica 2026 in Munich, with the reference hardware and associated files available for evaluation. The manufacturer has not published a universal interference rejection figure, a validated positioning accuracy improvement, or a completed receiver qualification result applicable to every configuration.

The platform supplies the antenna and RF hardware foundation for subsequent development. Final anti-jamming performance will depend on integration with suitable receiving electronics, adaptive processing algorithms, calibration procedures, and testing under the interference conditions relevant to the intended application.