Two New Antennas: Lightweight Triple Band for UAVs and More - Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design

Two New Antennas: Lightweight Triple Band for UAVs and More

Tallysman Wireless Inc. has added the low-profile triple-band HC997EXF to its line of embedded helical GNSS antennas.

The triple-band GNSS HC997EXF embedded helical antenna is designed for precise positioning, covering the GPS/QZSS-L1/L2/L5, GLONASS-G1/G2/G3, Galileo-E1/E5a/E5b, BeiDou-B1/B2/B2a, and NavIC-L5 frequency bands, including the satellite-based augmentation system (SBAS) available in the region of operation [WAAS (North America), EGNOS (Europe), MSAS (Japan), or GAGAN(India)], as well as L-band correction services.

The HC997EXF low-profile helical antenna is packaged in a very light (11 g) and compact form factor (60 mm wide and 25 mm tall). Its precision-tuned, high-accuracy helical element provides an excellent axial ratio and operates without a ground plane. These features make the HC997EXF ideal for lightweight unmanned aerial vehicle (UAV) navigation and a wide variety of precision applications.

eXtended Filtering (XF) enables the HC997EXF antenna to mitigate new and existing radio frequency bands that interfere with GNSS signals. For example, in North America, the planned Ligado service, which will broadcast in the frequency range of 1526 to 1536 MHz, could affect GNSS antennas that receive space-based L-band correction service signals (1539 – 1559 MHz). Similarly, LTE signals or their harmonics, such as the new LTE bands in Europe [Band 32 (1452 – 1496 MHz)] and Japan [Bands 11 and 21 (1476 – 1511 MHz)], have affected GNSS antennas and receivers. Lastly, the Inmarsat satellite communication uplink (1626.5 – 1660.5 MHz), commonly used on maritime vessels, can also affect nearby GNSS antennas.

The HC997EXF antenna base has a flying lead and a variety of connectors. To facilitate the installation, Tallysman provides an optional embedded helical mounting ring, which traps the outer edge of the antenna circuit board to the host circuit board or any flat surface. Tallysman provides support for installation, integration, and optimization of embedded helical antennas to ensure optimal antenna performance.

Surface Mount Antenna

Tallysman Wireless Inc. also adds the TW7976 to its surface mount line of antennas. The TW7976 covers GPS/QZSS-L1/L2, QZSS-L6, GLONASS-G1/G2, Galileo-E1/E6, and BeiDou-B1/B3, as well as L-band correction signals. The addition of L6 and E6 coverage supports the Galileo High Accuracy Service (HAS) and the QZSS Centimeter Level Augmentation Service (CLAS) correction signals. Regional augmentation services such as WAAS (North America), EGNOS (Europe), MSAS (Japan), GAGAN (India), and high-precision L-band correction services are also supported.

The TW7976 features a patented Tallysman® Accutenna®, which provides multi-constellation and multi-frequency support. Accutenna® technology offers an excellent axial ratio that mitigates multipath signals and produces clean code and phase measurements. Accutenna® antennas enable high-precision techniques, such as Real-Time Kinematic (RTK) and Precise Point Positioning (PPP), which provide accurate and precise position estimates (< 0.1 m). Another key feature of the TW7976 is a deep pre-filter that attenuates out-of-band signals. This is crucial in challenging urban environments where near-band and inter-modulated signal interference from LTE and other cellular bands is common.


The surface-mounted TW7976 weighs only 180 grams, is IP67-rated, and supports direct screw, magnet, or adhesive tape attachment. The TW7976 is ideal for many applications, including autonomous vehicle navigation (land, rail, sea, and air) and high-precision automotive and agricultural positioning.