#	Model	Frequency	Bandwidth	Gain	Download		ENQ
1.	QHA-1113	1100-1300 MHz	1.1 - 1.3 GHz	2 dBic
2.	QHA-1117	1100-1700 MHz	1100-1700MHz	2 dBic
3.	QHA-1216	1200-1600MHz	1.2 - 1.6 GHz	2 dBi
4.	QHA-1314	1300-1400 MHz	1.3 - 1.4 GHz	2dBi
5.	QHA-150	135-175MHz	20 MHz	3 dBic
6.	QHA-1417	1400-1700 MHz	1.4 - 1.7 GHz	2 dBic
7.	QHA-1516	1500-1620 MHz	1.50 - 1.62 Ghz	2 dBic
8.	QHA-1720	1700-2000 MHz	1.7 - 2.0 GHz	2 dBic
9.	QHA-1726	1700-2600 MHz	1.7-2.6 GHz.	2 dBic
10.	QHA-2023	2000-2300 MHz	2.0 - 2.3 GHz	2 dBic
11.	QHA-2326	2300-2600 MHz	2.3 - 2.6 GHz	2 dBic
12.	QHA-2630	2600-3000 MHz	2.6 - 3.0 GHz	2 dBic
13.	QHA-3040	3000-4000MHz	3.0 - 4.0 GHz	2 dBic
14.	QHA-350	300-400MHz	40 MHz	3 dBic
15.	QHA-4050	4000-5000MHz	4.0 - 5.0 GHz	2 dBic
16.	QHA-450	400-512MHz	70 MHz	3 dBic
17.	QHA-4854	4800-5400 MHz	4.8 - 5.4 GHz	2 dBic
18.	QHA-5060	5000-6000 MHz	5.0 - 6.0 GHz	2 dBic
19.	QHA-5458	5400-5800 MHz	5.4 - 5.8 GHz	2 dBic
20.	QHA-850	700-1000MHz	700 - 1000 MHz	3 dBic

Antenna Experts offer a complete products portfolio of military grade circular polarized horizontal omni quadrifilar helix antenna. Quadrifilar Helix Antennas are broadband omni-directional RHCP or LHCP quadrifilar helix antennas, rugged all weather model, enclosed in a ABS radome, uses high class copper alloy and does not require any field tuning or adjustments. The compact size of quadrifilar helix antennas RHCP omni or quadrifilar helix antennas LHCP omni-directional antenna allows easy handling, shipping and highly suitable for receiving, transmitting, scanning, monitoring, surveillance and jamming applications.

The quadifilar helix antenna are circular polarized omni antenna comprises two bifilar helical loops oriented in mutual orthogonal relationship on a common axis. The quadrifilar helix antennas terminals of each loop are fed in anti-phase and the currents in the two loops are in phase quadrature of these quadrifilar helix antenna. Quadrifilar helix antennas are high suitable as base station antenna for Ground To Air communication application without having the requirement of multiple antennas.

Quadrifilar Helix Architecture and Circular Polarization

The QHA series represents a sophisticated leap in military-grade antenna design, utilizing a quadrifilar helix (QHA) architecture. This design comprises two bifilar helical loops oriented in a mutually orthogonal relationship on a common axis. By feeding the terminals of each loop in anti-phase and maintaining currents in phase quadrature, the antenna achieves a true circular polarized omni-directional pattern. This technology, available in both Right Hand Circular Polarized (RHCP) and Left Hand Circular Polarized (LHCP) senses, delivers superior penetration through atmospheric obstructions and significantly reduces signal degradation caused by multipath interference.

Versatile Frequency Coverage for Global Navigation QHA

Antenna Experts manufactures an extensive range of QHAs designed to support the entire spectrum of global navigation and satellite communication. This includes dedicated models for all GPS bands (L1 through L6), as well as the GLONASS, IRIDIUM, and INMARSAT constellations. By providing a single, broadband omni-directional solution that covers these critical bands, the QHA eliminates the need for complex, multiple-antenna arrays on a single platform. This makes it an indispensable tool for Earth Observation Missions, Space Science Missions, and high-precision telemetry applications.

Ground-to-Air Communication and Tactical Jamming

The unique radiation characteristics of the quadrifilar helix antenna, featuring a wide elevation beam-width combined with 360-degree horizontal coverage, make it highly suitable for Ground-to-Air communication. These same properties allow the antenna to excel in tactical electronic warfare, specifically for scanning, monitoring, surveillance, and drone jamming. Because the QHA provides hemispherical-omni coverage, it can effectively engage aerial targets or maintain satellite links even when the orientation between the transmitter and receiver is dynamic or unpredictable.

"Teflon Dielectric" High-Power Transmission of QHA

To handle the intense thermal and electrical demands of high-power military applications, the QHA series incorporates a specialized "Teflon Dielectric Transmission Line" technique. This advanced internal matching system ensures a smooth Voltage Standing Wave Ratio (VSWR) and maintains constant gain over the specified bandwidth. This allows the antenna to handle significant power input without sacrificing efficiency, making it a reliable choice for high-wattage jamming systems and robust base station transmitters that require "set-and-forget" reliability without field tuning.

QHA Ruggedized Construction and Environmental Defense

Designed to survive the most extreme weather conditions, the QHA series features radiating elements made from high-class copper alloy, hermetically sealed within a UV-resistant ABS radome. This radome is not only transparent to RF signals but also possesses the structural integrity to withstand high wind loads and mechanical impact. The cylindrical geometry of the shell is engineered for low wind resistance and to mitigate the effects of ice formation. Furthermore, the use of stainless steel mounting hardware ensures that the system remains free from corrosion in saline coastal or humid tropical environments.

QHA-1117: Multiband Navigation and GPS Satellite Link 1100-1700MHz

The QHA-1117 is a specialized broadband hemi-omni-directional antenna designed to cover the critical 1100–1700 MHz range. This single-unit solution is optimized for multi-constellation support, providing seamless performance for GPS L1/L2/L5, Iridium, and GLONASS without requiring field adjustments. Its compact profile and rugged all-weather build make it a primary choice for weather station satellite reception and military-grade navigation. For absolute weather protection, the antenna termination is fitted directly below the mounting flange, shielding the connection point from the elements.

QHA-5060: High-Frequency Broadband Performance 5000-6000 MHz

Designed for higher frequency requirements, the QHA-5060 covers the entire 5000–6000 MHz band. This model maintains the same robust circular polarization and wide elevation beam-width as the rest of the series, making it ideal for advanced telemetry and high-frequency surveillance. Like its lower-frequency counterparts, the QHA-5060 is an "out-of-the-box" solution that requires no field tuning. Its compact size facilitates easy logistics and shipping, providing a high-performance alternative to much larger and more expensive directional or linear omni-directional antennas.

QHA-450: Quadrifilar Helix Broadband Performance 400-512 MHz

Designed for higher frequency requirements, the QHA-450 covers the entire 400–512 MHz band. This model maintains the same robust circular polarization and wide elevation beam-width as the rest of the series, making it ideal for advanced telemetry and high-frequency surveillance. Like its lower-frequency counterparts, the QHA-450 is an "out-of-the-box" solution that requires no field tuning. Its compact size facilitates easy logistics and shipping, providing a high-performance alternative to much larger and more expensive directional or linear omni-directional antennas.

QHA-850: Quadrifilar Helix Broadband Performance 700-1000 MHz

Designed for higher frequency requirements, the QHA-850 covers the entire 700-1000 MHz band. This model maintains the same robust circular polarization and wide elevation beam-width as the rest of the series, making it ideal for advanced telemetry and high-frequency surveillance. Like its lower-frequency counterparts, the QHA-850 is an "out-of-the-box" solution that requires no field tuning. Its compact size facilitates easy logistics and shipping, providing a high-performance alternative to much larger and more expensive directional or linear omni-directional antennas.
Tactical Integration and Diverse Mounting Options.

Logistical Flexibility of QHA Series Antennas

Logistical flexibility is a hallmark of the QHA series, which offers a wide array of mounting configurations to suit any platform. Standard options include mast mounting for fixed base stations, civilian vehicular mounts, and specialized NATO 4-hole flange mounts for armored military vehicles. The series is also available in ultra-lightweight versions for man-pack applications, ensuring that dismounted soldiers have access to reliable satellite communication. With the antenna termination recessed within the mounting hardware for complete environmental sealing, these antennas represent the pinnacle of tactical and commercial-grade circular polarized technology.

All Important Frequency Band Coverage from 150MHz to 6GHz

Antenna Experts also manufactured IRIDIUM band quadrifilar helix antenna, GLONASS band quadrifilar helix antenna, and INMARSAT bands quadrifilar helix antenna 800MHz quadrifilar helix antenna, 850MHz quadrifilar helix antenna, 900MHz quadrifilar helix antenna, 950MHz quadrifilar helix antenna, 450MHz quadrifilar helix antenna, 400MHz quadrifilar helix antenna, 2400MHz quadrifilar helix antenna, 5800MHz quadrifilar helix antenna 4400-6000MHz quadrifilar helix antenna 1100-1700MHz quadrifilar helix antenna 1200-1600MHz quadrifilar helix antenna 370-500MHz quadrifilar helix antenna 400-550MHz quadrifilar helix antenna 4.9-5.9GHz quadrifilar helix antenna

Quadrifilar Helix Antennas Application

Quadrifilar helix antennas are highly suitable for weather satellite communication, telemetry application, Earth Observation Missions, Space Science Missions, Global Navigation Satellite System GLONASS, L band GPS application including GPS L1, GPS L2 & GPS L5 band without having the requirement of multiple antennas. Quadrifilar Helix Antennas RHCP omni or Quadrifilar Helix Antennas LHCP omni antenna termination fitted at bottom of mounting flange for complete weather protection.

UV Resistant ABS Enclosure Radome

The UV resistant ABS enclosure has excellent transparency for RF signals and enough strength to withstand specified wind loads of these quadrifilar helix antennas. The stainless steel mounting hardware is supplied with the quadrifilar helix antenna. Cylindrical shell/enclosure is used for low wind loading and for minimal effect of ice formation on the quadrifilar helix antenna operation as well as providing an aesthetically pleasing appearance.