Products> Antenna Products > Wide Angle Scalar Feed Horns
Mi-Wave’s 263 Series Wide-Angle Scalar Feed Horn Antennas, also known as choke horns, are designed for RF, microwave, and millimeter-wave applications requiring broad beamwidth coverage, stable radiation performance, and reliable feed illumination.
With beamwidths of approximately 55 degrees, these antennas are well suited for low F/D parabolic reflector systems, including F/D ratios of 0.5 and 0.4, as well as offset feed antenna configurations. Their wide-angle radiation characteristics help provide uniform reflector illumination while reducing sensitivity to alignment and improving overall antenna system performance.
The scalar feed geometry helps control the electromagnetic field distribution at the antenna aperture, supporting low VSWR, predictable gain, stable beam symmetry, and polarization-insensitive operation. This makes the 263 Series a strong choice for reflector feed systems, surveillance equipment, radar platforms, communication systems, and high-frequency test environments.
Features
• Low VSWR
• Wide Beamwidths
• Polarization Insensitive
• Partial Waveguide Bandwidths
Applications
• Low F/D Antennas
• Surveillance Systems
• Offset Feed Antenna
The standard models shown represent only part of Mi-Wave’s broader product capabilities. Custom configurations are available to support specific frequency bands, interfaces, and application requirements, enabling optimized solutions for specialized RF, microwave, and millimeter-wave systems.
*Actual product may be different from the image shown per customers specifcations
*All data presented is collected from a sample lot.
* Actual data may vary unit to unit, slightly.
*All testing was performed under +25 °C case temperature.
*Consult factory to confirm if material, plating, size, shape, orientation and any electrical parameter is critical for the application as website information is for reference only.
*Millimeter Wave Products, Inc. reserves the right to change the information presented on website without notice as we continue to enhance the performance and design of our products.
Key Features & Performance Benefits
Wide Beamwidth Coverage (~55° Typical)
Engineered to provide broad angular radiation, enabling effective illumination of low F/D ratio reflector antennas (F/D = 0.4–0.5). This wide beam ensures proper edge illumination without excessive spillover, improving overall system efficiency.
Scalar Feed Geometry for Controlled Field Distribution
The integrated scalar feed structure shapes the electromagnetic field at the aperture, enabling uniform amplitude and phase distribution. This results in improved reflector illumination, reduced sidelobes, and better system-level performance.
Broadband Frequency Coverage (12.4 – 110 GHz)
Supports operation across microwave and millimeter-wave bands, reducing the need for multiple feed antennas in wideband systems and simplifying system design.
Low VSWR and Broadband Impedance Matching
Maintains excellent impedance match across the operating band, minimizing reflections and ensuring efficient RF power transfer from the waveguide to free space.
Stable Gain and Repeatable Performance
Provides consistent gain and radiation characteristics across frequency, enabling repeatable system performance in both laboratory and field environments.
Consistent Polarization Performance
Maintains stable polarization characteristics, which is critical for systems requiring precise signal integrity, polarization alignment, and cross-polarization suppression.
Optimized for Reflector Feed Applications
Specifically designed for use with prime focus and offset reflector antennas, ensuring proper illumination, minimized spillover, and enhanced aperture efficiency.
Reduced Spillover and Improved System Efficiency
Controlled beam shaping reduces energy loss outside the reflector, improving link efficiency, noise performance, and system gain.
Low Insertion Loss and Efficient Energy Transition
Efficient waveguide-to-free-space transition minimizes loss, supporting high-performance RF and mmWave systems.
Standard Waveguide Interface Compatibility
Available with standard waveguide flanges for seamless integration into RF, microwave, and millimeter-wave systems.
Custom Design Flexibility
Supports custom configurations including frequency bands, waveguide sizes, polarization types, beamwidth optimization, and mechanical packaging.
How Wide-Angle Scalar Feed Horn Antennas Work
Wide-angle scalar feed horn antennas are designed to provide broad beamwidth coverage, stable radiation patterns, and efficient reflector illumination across RF, microwave, and millimeter-wave frequency ranges.
Unlike standard horn antennas that prioritize narrow beam formation and maximum directivity, wide-angle scalar feed horns are engineered to intentionally spread RF energy over a larger angular region while maintaining controlled field distribution and predictable beam behavior.
Mi-Wave’s Series 263 Wide-Angle Scalar Feed Horn Antennas combine a scalar feed structure with a wide-flare horn geometry to generate beamwidths of approximately 55 degrees, making them ideal for low F/D reflector systems and offset feed antenna configurations.
The scalar ring geometry helps shape the electromagnetic field at the antenna aperture, supporting smooth reflector illumination, reduced spillover, stable polarization performance, and improved aperture efficiency. These characteristics are especially important in reflector-fed systems where feed illumination directly affects gain, sidelobe performance, and overall antenna efficiency.
RF Energy Enters the Waveguide
RF energy enters the antenna through a waveguide interface that guides electromagnetic energy into the scalar feed horn structure with low loss and controlled mode propagation.
Scalar Rings Shape the RF Field
The scalar ring geometry helps control electromagnetic field distribution at the aperture, improving beam symmetry while reducing edge diffraction and spillover.
Wide-Flare Horn Expands the Beam
The horn flare geometry spreads RF energy across a broader angular region to create wide beamwidth coverage optimized for reflector illumination.
Reflector Illumination Improves
Wide-angle beam coverage helps illuminate low F/D and offset reflectors more evenly, improving aperture efficiency and overall antenna system performance.
Stable Radiation Performance
Controlled field distribution supports predictable beam patterns, low VSWR, stable polarization behavior, and repeatable RF performance across the operating band.
Optimized for Reflector Systems
Wide-angle scalar feed horns are commonly integrated into low F/D reflector systems, offset feed antennas, radar systems, communication platforms, and RF measurement environments.
How to Choose the Right Wide-Angle Scalar Feed Horn
Selecting the correct wide-angle scalar feed horn depends on reflector geometry, operating frequency, beamwidth requirements, polarization performance, and overall RF system architecture.
Reflector F/D Ratio
Wide-angle scalar feed horns are commonly selected for low F/D reflector systems such as 0.5 and 0.4 F/D parabolic reflectors where broader illumination angles are required.
Beamwidth Requirements
Engineers select beamwidth based on reflector geometry and illumination requirements. Wider beamwidths improve reflector coverage while helping reduce feed blockage and spillover.
Operating Frequency
Frequency range directly affects waveguide size, horn dimensions, and aperture behavior. Higher frequencies generally require tighter dimensional tolerances and more precise feed alignment.
Polarization Requirements
Systems may require linear, circular, or dual-polarized operation depending on communication or radar requirements. OMT integration may also be required for dual-channel systems.
Waveguide Interface Compatibility
Proper waveguide sizing and interface selection are important for minimizing mismatch, reducing loss, and simplifying RF system integration.
Environmental Conditions
Outdoor systems may require consideration for thermal expansion, moisture exposure, vibration, corrosion resistance, and long-term environmental durability.
Gain & Illumination Efficiency
Feed horn selection impacts reflector illumination efficiency, sidelobe levels, aperture utilization, and overall antenna gain performance.
System Integration
Wide-angle scalar feed horns are often integrated with reflector antennas, OMTs, LNAs, HPAs, frequency converters, and other RF subsystem components.
Applications
Wide-Angle Scalar Feed Horn Applications
Mi-Wave Wide-Angle Scalar Feed Horn Antennas are used in systems that require broad beamwidth, controlled illumination, and predictable radiation performance across RF, microwave, and millimeter-wave frequencies.
Satellite Communications (SatCom)
These antennas are commonly used as feed horns for reflector-based satellite systems, where proper illumination and efficiency are critical.
Typical applications include:
- Satellite ground terminals and gateway systems
- Reflector-fed antenna systems
- Ka-band, Q-band, and V-band SatCom links
- Feeder link and high-throughput satellite systems
- Satellite payload testing and validation
Their wide beamwidth ensures proper reflector illumination, improving link margin, gain, and system reliability.
Reflector Antenna Feed Systems
Wide-angle scalar feed horns are specifically optimized for low F/D reflector configurations, including both prime focus and offset designs.
Typical applications include:
- Prime focus reflector antennas
- Offset reflector antennas
- Compact reflector systems with low F/D ratios
- High-efficiency antenna systems
- Custom reflector feed designs
These antennas help achieve uniform aperture illumination and reduced edge taper loss, improving overall antenna performance.
Radar Systems
Used in radar applications where controlled illumination and wide coverage are required.
Common applications include:
- Reflector-fed radar systems
- FMCW and pulse radar platforms
- Radar calibration and system verification
- Millimeter-wave radar research
- Wide-area sensing systems
Their stable radiation pattern supports accurate signal transmission and reception.
Antenna Measurement Ranges
Widely used in RF measurement environments where repeatability and pattern control are essential.
Typical applications include:
- Antenna gain and pattern measurements
- Near-field and far-field testing
- Calibration of reflector systems
- Beamwidth and sidelobe analysis
- RF system validation
RF Test & Measurement Systems
Used in laboratory and production environments for RF component and system evaluation.
Typical applications include:
- RF subsystem characterization
- System-level testing
- Signal propagation experiments
- Measurement system calibration
Millimeter-Wave Systems
Supports high-frequency applications where broadband performance and controlled beam coverage are required.
Typical applications include:
- 5G and advanced wireless research
- mmWave communication systems
- High-frequency sensing applications
- Experimental RF platforms
Research and Development (R&D)
Used in advanced research environments requiring flexibility, repeatability, and wideband performance.
Typical applications include:
- Academic research programs
- Government and defense research
- Advanced antenna development
- Prototype system validation
- Electromagnetic studies
EMC and RF Test Facilities
Used in environments requiring controlled radiation and predictable field distribution.
Typical applications include:
- Radiated emissions testing
- RF susceptibility testing
- Controlled illumination setups
- EMC compliance verification
Frequently Asked Questions
What is a wide-angle scalar feed horn antenna?
A wide-angle scalar feed horn is a specialized antenna designed to produce a broad beamwidth with controlled field distribution, making it ideal for illuminating reflector antennas.
How is a scalar feed horn different from a standard horn antenna?
Scalar feed horns incorporate structures that control amplitude and phase distribution, improving reflector illumination, reducing sidelobes, and increasing efficiency.
Why is beamwidth important for reflector antennas?
Beamwidth determines how evenly the reflector is illuminated. Proper beamwidth improves gain, efficiency, and sidelobe performance, while reducing spillover losses.
What is the typical beamwidth of these antennas?
Series 263 antennas typically provide beamwidths of approximately 55 degrees, optimized for low F/D reflectors.
What does F/D ratio mean?
F/D is the ratio of the reflector’s focal length to its diameter. Lower F/D ratios require wider beamwidth feeds to properly illuminate the reflector surface.
What frequency range is supported?
These antennas operate from 12.4 GHz to 110 GHz, covering microwave and millimeter-wave frequency bands.
Are these antennas suitable for millimeter-wave applications?
Yes. They are designed to perform consistently across both microwave and mmWave frequencies.
What are the advantages of wide-angle feed horns?
They provide broad coverage, improved reflector illumination, reduced spillover, and stable radiation patterns, leading to better system performance.
Can these antennas be used in radar systems?
Yes. They are used in reflector-fed radar systems, calibration setups, and experimental radar platforms.
Are these antennas customizable?
Yes. Mi-Wave offers custom options for frequency ranges, waveguide interfaces, polarization, and mechanical configurations.
Wide-Angle Scalar Feed Horn Engineering Calculators
These RF engineering calculators help estimate antenna performance for wide-angle scalar feed horn antennas, including reflector feed systems, satellite communications platforms, radar systems, antenna measurement ranges, and microwave and millimeter-wave test environments. Use them to calculate antenna gain, beamwidth, aperture size required for target gain, effective aperture, free-space path loss, and wavelength across RF, microwave, and millimeter-wave frequencies.
Wide-angle scalar feed horns are designed for broad beamwidth, controlled reflector illumination, low VSWR, and stable radiation characteristics. A typical starting efficiency range for many systems is 0.50 to 0.75.
Antenna Gain Calculator
Antenna Gain (dBi):
Antenna Beamwidth Calculator
Aperture Size Required for Target Gain
Antenna Effective Aperture Calculator
Effective Aperture (m²):
Free Space Path Loss Calculator
RF Wavelength Calculator
Wavelength (mm):
Glossary of Wide-Angle Scalar Feed Horn Antenna Terms
This glossary defines key concepts related to wide-angle scalar feed horn antennas, which are used in RF, microwave, and millimeter-wave systems requiring broad beamwidth, controlled reflector illumination, and stable radiation performance.
Antenna Fundamentals
Scalar Feed Horn
A horn antenna designed with features that control electromagnetic field distribution, improving reflector illumination, reducing sidelobes, and enhancing overall system efficiency.
Wide-Angle Feed Horn
An antenna designed to produce a broad beamwidth, typically around 55°, used for illuminating reflector antennas with low F/D ratios.
Horn Antenna
A flared waveguide structure that transitions RF energy into free space with controlled directivity.
Radiation Pattern
The spatial distribution of RF energy radiated by an antenna.
Symmetrical Radiation Pattern
A radiation pattern that is uniform across azimuth, providing consistent coverage.
Main Lobe
The primary direction where the majority of RF energy is radiated.
Sidelobes
Secondary radiation lobes that represent energy outside the main beam.
Back Lobe
Radiation emitted in the opposite direction of the main beam.
Reflector System Terms
F/D Ratio (Focal Length to Diameter)
A critical parameter in reflector antennas that determines feed beamwidth requirements and illumination efficiency.
Reflector Illumination
The distribution of RF energy across the reflector surface, which directly impacts antenna performance.
Edge Taper
The reduction in signal amplitude at the edges of the reflector to control sidelobes and spillover.
Spillover Loss
RF energy that extends beyond the reflector surface, reducing efficiency and increasing noise.
Aperture Efficiency (η)
The effectiveness of converting RF power into a focused beam by the reflector system.
Prime Focus Reflector
A reflector configuration where the feed antenna is located at the focal point.
Offset Reflector
A reflector design that minimizes feed blockage and improves efficiency.
Electrical Performance Terms
Gain (dBi)
A measure of how effectively an antenna directs RF energy compared to an isotropic radiator.
Directivity
The degree to which an antenna concentrates energy in a specific direction.
VSWR (Voltage Standing Wave Ratio)
A measure of impedance matching between the antenna and transmission line.
Return Loss (dB)
The amount of reflected signal due to impedance mismatch.
Insertion Loss
Signal loss as RF energy passes through the antenna.
Polarization
The orientation of the electric field of the RF signal.
Cross-Polarization
Unwanted orthogonal polarization components that degrade signal quality.
Phase Center
The apparent origin point of the radiated wavefront, important in reflector alignment.
RF and Frequency Terms
Radio Frequency (RF)
Electromagnetic waves used for communication, sensing, and signal transmission.
Microwave Frequencies
Typically defined as frequencies from 1 GHz to 30 GHz.
Millimeter-Wave (mmWave)
Frequencies from 30 GHz to 300 GHz.
Frequency Band
A defined range of frequencies used for specific applications.
Bandwidth
The range of frequencies over which an antenna performs effectively.
Wavelength (λ)
The physical length of one cycle of an electromagnetic wave.
Waveguide and Interface Terms
Waveguide
A structure used to guide electromagnetic energy, particularly at microwave and mmWave frequencies.
Waveguide Size (WR Designation)
Standardized waveguide dimensions corresponding to frequency ranges.
Flange Interface
A mechanical interface used to connect waveguide components.
Mode (TE/TM Modes)
The electromagnetic field distribution inside a waveguide.
Cutoff Frequency
The minimum frequency at which a waveguide mode can propagate.
Performance and Efficiency
Aperture
The opening of the antenna through which RF energy is radiated.
Field Distribution
The spatial variation of electromagnetic energy across the antenna aperture.
Efficiency (η)
The ratio of radiated power to input power.
Gain Stability
Consistency of antenna gain across frequency.
Alignment Sensitivity
The degree to which antenna performance depends on positioning accuracy.
Thermal Stability
The ability of the antenna to maintain performance across temperature variations.
Materials and Construction
Conductive Materials
Materials such as aluminum or copper used to minimize RF losses.
Surface Finish
The smoothness of the antenna surface, critical at higher frequencies.
Mechanical Tolerance
The allowable dimensional variation in manufacturing.
Precision Machining
High-accuracy fabrication required for millimeter-wave performance.
Applications and Systems
Satellite Communications (SatCom)
Systems used to transmit and receive signals to and from satellites.
Radar Systems
Systems that use RF signals for detection, tracking, and ranging.
Antenna Measurement Range
A controlled environment used to test antenna performance.
Test and Measurement Systems
Equipment used to evaluate RF components and systems.
Research and Development (R&D)
Experimental and engineering development environments.
EMC Testing
Electromagnetic compatibility testing to ensure systems do not interfere with each other.
Frequency Bands (Typical)
- Ku-Band: 12–18 GHz
- K-Band: 18–27 GHz
- Ka-Band: 26–40 GHz
- Q-Band: 33–50 GHz
- V-Band: 50–75 GHz
- W-Band: 75–110 GHz
Note: Our website contains just a few types of Antennas we build. Consult with us for your specific needs.
| Model | Band Type | Minimum Frequency (GHz) | Maximum Frequency (GHz) | Gain (dBi) | 3dB Beamwidth, E-Plane (Degrees) | 3dB Beamwidth, H-Plane (Degrees) | Polarization | RF Ports | LINK |
|---|---|---|---|---|---|---|---|---|---|
| 263A-XX/.XXX/381 | Ka-Band | 26.5 | 40 | 10 | 55 | 56 | Circular | 0.250" Circular waveguide diameter | |
| 263A-XX/.XXX/599 | Ka-Band | 26.5 | 40 | 10 | 55 | 56 | Circular | 0.281" Circular waveguide diameter | |
| 263B-XX/.XXX/384 | Q-Band | 33 | 50 | 10 | 55 | 56 | Linear & Circular | .250" ID Circular Waveguide (33-38.5 GHz) | |
| 263U-XX/.XXX/383 | U-Band | 40 | 60 | 10 | 55 | 56 | Linear & Circular | .219" ID Circular Waveguide (40-43 GHz) | |
| 263V-XX/.XXX/385 | V-Band | 50 | 75 | 10 | 55 | 56 | Linear & Circular | .165" ID Circular Waveguide (50-58 GHz) | |
| 263E-XX/.XXX/387 | E-Band | 60 | 90 | 10 | 55 | 56 | Linear & Circular | .141" ID Circular Waveguide (60-68 GHz) | |
| 263W-XX/.XXX/387 | W-Band | 75 | 110 | 10 | 55 | 56 | Linear & Circular | .125" ID Circular Waveguide (75-77 GHz) |
*All data presented is collected from a sample lot.
* Actual data may vary unit to unit, slightly.
*All testing was performed under +25 °C case temperature.
*Consult factory to confirm if material, plating, size, shape, orientation and any electrical parameter is critical for the application as website information is for reference only.
*Millimeter Wave Products, Inc. reserves the right to change the information presented on website without notice as we continue to enhance the performance and design of our products.
Interested in this product or other Mi-Wave solutions?
Contact our team to discuss your frequency range, interface needs, and application requirements.
Custom configurations are available for specialized RF, microwave, and millimeter-wave systems.
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