How does a three-mode active navigation and positioning module antenna ensure the stability of navigation signals through anti-interference design?
Publish Time: 2025-11-05
With the widespread application of Global Navigation Satellite Systems (GNSS) such as BeiDou, GPS, GLONASS, and Galileo, high-precision positioning has penetrated into autonomous driving, drones, intelligent transportation, surveying and mapping, and military fields. However, the real environment is filled with various electromagnetic radiation sources such as communication base stations, radar, Wi-Fi, Bluetooth, and high-voltage power lines, which can easily interfere with or even suppress weak satellite navigation signals. Against this backdrop, the three-mode active navigation and positioning module antenna, through a series of advanced anti-interference designs, builds a reliable barrier for navigation signals in the complex electromagnetic "battlefield," ensuring the continuity and stability of positioning services.1. Multi-band Cooperative Reception, Enhancing Signal Redundancy and RobustnessThe core advantage of the three-mode active navigation and positioning module antenna lies in its ability to simultaneously receive signals from multiple frequency points of multiple navigation systems. When a certain frequency band fails due to severe interference, the receiver can automatically switch to other unaffected frequency bands to continue operating. This "multi-source redundancy" mechanism significantly improves the system's survivability when local frequency bands are disturbed. For example, in urban canyons or near high-voltage substations, the L1 band may be overwhelmed by strong noise, but high-bit-rate signals such as L5 or B2a, due to their wider bandwidth and stronger noise immunity, can still maintain effective positioning.2. High-selectivity filtering design, precisely "screening" out useful signalsTo suppress out-of-band interference, the three-mode active navigation and positioning module antenna integrates multiple stages of high-Q bandpass filters. These filters are precisely tuned for each navigation frequency band, with steep passbands and large stopband attenuation, effectively filtering out communication signals and broadband noise from adjacent frequency bands. Some high-end antennas also employ SAW or BAW filtering technology, achieving excellent frequency selectivity while miniaturizing, ensuring that only clean satellite signals enter the receiving channel.3. Low-noise amplification and dynamic gain control, optimizing signal-to-noise ratioWeak satellite signals are easily overwhelmed by the noise of the receiving link itself after long-distance transmission. The three-mode active navigation and positioning module antenna incorporates an ultra-low noise amplifier, with the noise figure typically controlled below 0.8 dB, maximizing the signal-to-noise ratio. Meanwhile, to prevent LNA saturation due to strong interference, advanced designs incorporate automatic gain control or anti-saturation circuits. These dynamically reduce gain upon detecting sudden strong signals, protecting downstream circuitry and maintaining a smooth signal path.4. Antenna Structure Optimization to Suppress Multipath and Polarization InterferenceThree-mode active navigation and positioning module antennas often employ right-hand circular polarization, consistent with the satellite's transmitted signal polarization. This effectively suppresses left-hand circular or linear polarization multipath interference caused by ground reflections and building scattering. Their radiating elements are optimized through electromagnetic simulation, possessing excellent low-elevation gain and back-lobe suppression capabilities, reducing spurious signal coupling from the ground or sides. Some anti-interference models also integrate a choke grounding network, further weakening low-elevation multipath interference by constructing electromagnetic "traps," improving positioning accuracy in urban or mountainous environments.5. Intelligent Anti-interference Algorithm Collaboration for Integrated Hardware and Software ProtectionThree-mode active navigation and positioning module antennas often work in deep collaboration with the receiver, supporting interference detection and suppression functions. The antenna can monitor the spectrum environment in real time, feeding back interference characteristics to the receiver and triggering adaptive filtering, beamforming, or signal reconstruction algorithms to achieve end-to-end anti-interference from "hardware filtering" to "intelligent identification."In today's increasingly complex electromagnetic environment, the three-mode active navigation and positioning module antenna is not only a signal receiver but also the "first line of intelligent defense" for navigation systems. Through multiple anti-interference designs, including multi-frequency redundancy, precision filtering, low-noise amplification, polarization matching, and intelligent coordination, it accurately captures weak satellite signals amidst a deluge of noise, ensuring highly reliable positioning.
