Polarization is a critical factor in GNSS antenna design, as it determines how effectively the antenna can receive signals from satellites. This four-arm helical antenna employs right-hand circular polarization (RHCP), a standard for GNSS applications due to its ability to match the polarization of signals transmitted by satellites. RHCP offers significant advantages over linear polarization, particularly in dynamic environments where the antenna’s orientation may change. Unlike linear polarization, which is sensitive to the angle between the antenna and the satellite, RHCP ensures consistent signal reception regardless of the antenna’s tilt or rotation. This is especially valuable in applications such as drones, where the antenna may be in constant motion, or in surveying, where the antenna’s position relative to the sky can vary. Additionally, RHCP minimizes the impact of multipath interference—signal reflections from surfaces like buildings or water—by reducing the strength of reflected signals, which tend to be left-hand circularly polarized (LHCP). This results in cleaner, more reliable data, a key requirement for precision positioning.

The antenna operates across a broad frequency range of 1154-1300 MHz and 1525-1621 MHz, covering a comprehensive set of GNSS bands: GPS L1 (1575.42 MHz)/L2 (1227.60 MHz), GLONASS L1 (1602 MHz)/L2 (1246 MHz), BDS (BeiDou) B1 (1561.098 MHz)/B2 (1207.14 MHz)/B3 (1268.52 MHz), and GALILEO E1 (1575.42 MHz)/E2 (1278.75 MHz)/E5a (1176.45 MHz)/E5b (1207.14 MHz). This extensive frequency coverage is a hallmark of the four-arm helical design, which is inherently capable of supporting multiple bands without sacrificing performance. By tapping into signals from multiple constellations and bands, the antenna ensures redundancy, reducing the risk of signal loss due to atmospheric interference, satellite outages, or geographical limitations. For example, GPS L2 and GLONASS L2 bands provide enhanced accuracy through carrier phase measurements, while BeiDou B3 offers improved performance in Asia-Pacific regions. Galileo’s E5a and E5b bands, designed for high-precision applications, add another layer of reliability, particularly in urban or challenging environments. This multi-band capability makes the antenna a versatile tool for global applications, from mapping in remote areas to supporting autonomous vehicles in dense cities.

LNA gain—a measure of the antenna’s low-noise amplifier’s ability to boost weak signals—is specified as 32 ± 3 dB (typical at 25°C). The LNA is a critical component in GNSS antennas, as it amplifies faint satellite signals (which can be as weak as -160 dBm when they reach Earth’s surface) while introducing minimal additional noise. A high LNA gain ensures that even the weakest signals are amplified to a level that the receiver can process, improving the antenna’s ability to track satellites in challenging conditions such as dense foliage, urban canyons, or deep valleys. The tight tolerance of ±3 dB indicates consistent performance across units, ensuring that users can rely on predictable results regardless of the specific antenna they deploy. This consistency is particularly important in applications where multiple antennas are used in a network, such as in precision agriculture or infrastructure monitoring, where data from different stations must be seamlessly integrated.

The antenna’s peak gain of ≥1.5 dBi is deliberately optimized for the four-arm helical design, balancing signal amplification with radiation pattern width. While higher gain antennas may offer stronger signal amplification in specific directions, they often have narrow radiation patterns that require precise alignment—a challenge in dynamic environments. The 1.5 dBi gain, by contrast, ensures a broad radiation pattern, allowing the antenna to receive signals from satellites across a wide range of elevations and azimuths. This is critical for maintaining connectivity with multiple satellites simultaneously, a requirement for accurate positioning. In applications such as drones or moving vehicles, where the antenna’s orientation is constantly changing, a broad radiation pattern prevents signal dropouts and ensures continuous tracking of satellites.

VSWR (Voltage Standing Wave Ratio) is a key indicator of how efficiently the antenna transfers power from the receiver to the electromagnetic field. This antenna boasts impressive VSWR specifications: ≤1.5 (typical), ≤1.8:1 (typical), and 2.0:1 (maximum). A VSWR of 1:1 represents perfect impedance matching, with all power transferred to the field, while higher values indicate that some power is reflected back to the source. The low VSWR of this antenna ensures efficient power transfer, minimizing signal loss and maximizing the strength of received signals. This efficiency is particularly important in low-signal environments, where every decibel of power counts. For surveyors and engineers relying on precise positioning data, low VSWR translates to more reliable satellite tracking and reduced errors in their measurements.

With an impedance of 50 ohms, the antenna aligns with the standard impedance of most GNSS receivers and coaxial cables. Impedance matching is critical for maximizing power transfer and minimizing signal reflections, which can degrade performance. By adhering to the 50-ohm standard, the antenna ensures seamless integration with existing equipment, eliminating the need for additional matching components that would add complexity and cost. This compatibility is a key advantage for users looking to upgrade their systems without overhauling their entire setup.