DME-960-1240-9

The DME-960-1240-9 is a high-performance Fiberglass Omnidirectional Collinear Antenna specifically engineered for Distance Measuring Equipment (DME) applications within the 960–1240 MHz frequency band. This rugged, all-weather phased array delivers a consistent 9 dBi gain across the entire bandwidth without the need for a ground plane or field tuning. Built with 6063T6 architectural aluminum and high-grade brass, it is designed to serve as a critical navigation hub in the most demanding aeronautical and tactical environments.

Design: Precision Phased Array for Aviation Navigation

The DME-960-1240-9 features an advanced center-fed collinear dipole phased array design. This architecture is vital for aeronautical applications as it eliminates radiation pattern distortion and ensures a true, symmetrical 360-degree horizontal pattern. By vertically stacking large-diameter brass elements fed in phase, the antenna achieves an 18-degree vertical beamwidth. This focuses RF energy effectively toward the horizon, providing a constant 9 dBi gain that ensures reliable signal interception for aircraft across the entire broadband frequency range.

Construction: Engineered for Extreme Survivability

Built for ultimate mechanical integrity, the DME-960-1240-9 utilizes fully welded internal junctions to prevent RF inter-modulation and maintain signal purity. The radiating structure is completely housed within a high-tech ruggedized fiberglass radome, specifically designed to control friction-induced static caused by wind-blown dust and sand. All exposed metallic components are finished with an epoxy-based powder coating, providing total protection against salt spray, acid rain, and ultraviolet radiation in coastal or desert environments.

Reliability: Advanced Monitoring & Environmental Shielding

This antenna is an all-weather powerhouse engineered to meet rigorous MIL-STD-810G standards for shock, vibration, and extreme temperatures. For mission-critical navigation hubs, the antenna offers an optional coupler and dual monitoring probes. These probes allow real-time monitoring of the radiated signal at a level of -25 dB ± 1 dB below the input power. With marine-grade 316 stainless steel hardware and a wind rating of 200 Km/Hr, the DME-960-1240-9 provides a "set-and-forget" solution for essential distance measuring infrastructure.

Technical Features

• Broadband 960–1240 MHz Coverage: Optimized for the full DME frequency spectrum without the need for field adjustments.
• High-Intensity 9 dBi Gain: Focused 18-degree vertical aperture delivers superior signal reach for aeronautical navigation.
• No Ground Plane Required: Simplifies installation on various masts and structures while maintaining peak performance.
• Friction Static Control: Specialized design mitigates static buildup from wind and dust, protecting sensitive receiver electronics.
• MIL-STD-810G Compliant: Certified for high/low temperature, humidity, shock, vibration, rain, fungus, and salt fog.
• Fully Welded Internal Junctions: Prevents PIM (Passive Inter-Modulation) for a cleaner, high-fidelity radio signal.
• Optional Signal Monitoring: Available coupler and probes provide precise -25 dB signal feedback for system health checks.
• Marine Grade 316 Stainless Steel: Includes high-quality mounting hardware for maximum corrosion resistance in coastal zones.
• Rugged Fiberglass Radome: 45mm diameter enclosure provides excellent RF transparency and physical protection.
• High-Power 150W Capacity: Robust electrical design handles the demanding power requirements of distance measuring equipment.

DME Site Optimization Guide: Enhancing Navigation Reliability with the DME-960-1240-9

In the critical 960–1240 MHz aeronautical band, Distance Measuring Equipment (DME) must provide 24/7 precision, often in isolated or harsh environments. The DME-960-1240-9 is engineered to address the specific physical and electrical challenges of ground-to-air navigation, specifically focusing on signal purity and environmental hardening.

1. Mitigating Friction-Induced Static (E-Field Management)

In desert environments or high-wind coastal areas, airborne particles (sand, dust, or salt) rubbing against a standard fiberglass radome can create a massive buildup of static electricity.

• The "Quiet" Radome: The DME-960-1240-9 features a specialized radome design that allows for the controlled dissipation of friction-induced static.
• Receiver Protection: Without this feature, static discharges can create "RF noise bursts" that interfere with the delicate pulse-pair timing of DME signals. By draining this charge safely, the antenna maintains a low noise floor, ensuring the ground station can accurately "hear" distant aircraft interrogators even during sandstorms.

2. Center-Fed Phased Array: Ensuring Pulse Integrity

DME relies on precise timing between transmitted and received pulse pairs. Any distortion in the radiation pattern can lead to "distance errors" or loss of lock.

• True Omni-Directional Symmetry: The Center-Fed design ensures that the 9 dBi gain is perfectly symmetrical. Unlike end-fed antennas that may have a signal "tilt" at different frequencies, this phased array maintains a rock-solid 18-degree vertical beam across the entire 280 MHz bandwidth.
• Constant Timing: This stability ensures that the signal phase and amplitude remain constant for an aircraft regardless of its bearing to the station, which is essential for the high-precision requirements of modern aviation.

3. Integrated Signal Monitoring (Coupler & Probes)

For high-reliability sites (Category I/II/III ILS/DME), the ability to monitor the "near-field" radiated signal is a safety requirement.

• Real-Time Health Checks: The optional -25 dB monitoring probes provide a direct sample of the actual radiated energy. If the antenna’s performance degrades due to physical damage or internal failure, the ground station monitor can detect the shift immediately via the probe output.
• Redundancy: By using dual probes, site technicians can cross-reference signal health, ensuring that the navigation data being broadcast to aircraft is always within the strict tolerances required by aviation authorities.

4. Environmental Hardening: Salt, Sand, and Ice

DME stations are frequently located in exposed areas, from salt-heavy shorelines to freezing mountain peaks.

• Welded Reliability: All internal brass elements are fully welded. This prevents "mechanical noise" (PIM) caused by vibrations in 200 Km/Hr winds, which could otherwise corrupt the digital pulse data.
• Corrosion Resistance: The combination of 6063T6 aluminum, marine-grade 316 stainless steel, and epoxy powder coating ensures that the antenna will not degrade electrically due to oxidation, even after years of exposure to acid rain or salt spray.

DME Deployment Checklist

• Clearance and Siting: The DME-960-1240-9 does not require a ground plane, but it should be mounted at the highest possible point on the mast to ensure a clear "Radio Horizon."
• Probe Calibration: If using the optional monitoring probes, ensure the cables connecting the probes to the monitor are phase-stable and high-quality to maintain the ± 1 dB accuracy of the feedback signal.
• Lightning Protection: While the antenna is rugged, ensure the 51mm aluminum support pipe is bonded to a dedicated lightning ground. The fiberglass radome protects the elements, but a direct strike to the mast requires a low-resistance path to earth.

• Connector Weatherproofing: The N-Female termination is housed at the bottom of the antenna. Always use a professional weatherproofing kit (butyl rubber and UV-resistant tape) to prevent moisture wicking, which is the most common cause of DME system failure.