AD-100 V2.0 Half-Wave Tuned Dipole Antenna Kit
The Gold Standard Reference Antenna for EMI/EMC Testing | 30 MHz - 1 GHz
What is a Dipole Antenna?
A dipole antenna is the most fundamental and widely recognized antenna design in radio frequency engineering. It consists of two conductive elements (typically metal rods or wires) of equal length, positioned in a straight line with a small gap between them where the feedline connects. The name "dipole" comes from the Greek words "di" (two) and "pole," referring to its two-pole structure.
The Physics Behind Dipole Antennas
When an alternating current flows through a dipole antenna, it creates oscillating electric and magnetic fields that radiate outward as electromagnetic waves. A half-wave dipole, like the AD-100 V2.0, has a total length approximately equal to half the wavelength of the frequency it's designed to receive or transmit. This resonant length creates maximum efficiency in converting electrical energy to electromagnetic radiation (and vice versa).
Half-Wavelength Calculation:
Length (meters) = 150 / Frequency (MHz)
Each element length = λ/4 (quarter wavelength)
Why Dipoles are Reference Antennas
Dipole antennas hold a unique position in electromagnetic compatibility (EMC) and electromagnetic interference (EMI) testing as reference antennas. This designation means they serve as the standard against which all other antennas are calibrated and measured. Here's why:
Key Characteristics of Reference Antennas:
- Predictable Radiation Pattern: Half-wave dipoles have a well-defined, figure-eight radiation pattern that is theoretically calculable and reproducible
- Known Impedance: At resonance, a dipole presents a predictable impedance (approximately 73Ω in free space, 50Ω when properly matched)
- Calculable Antenna Factor: The antenna factor can be mathematically derived rather than requiring extensive measurement
- Standardized Design: International standards (ANSI C63.5, CISPR 16-1-4) specify exact dipole designs for consistency
- No Complex Components: Unlike log-periodic or broadband antennas, dipoles have minimal complexity, reducing measurement uncertainty
The Role in EMC Testing Standards
According to ANSI C63.4 and CISPR 16-1-4, half-wave dipole antennas are:
- The Only Acceptable Antenna for calibrating broadband antennas using the reference antenna method
- Mandatory for Normalized Site Attenuation (NSA) measurements of Open Area Test Sites (OATS) and Semi-Anechoic Chambers (SAC)
- Required for discrete frequency field strength measurements in compliance testing
- The Standard for Effective Radiated Power (ERP) and Effective Isotropic Radiated Power (EIRP) measurements of RF transmitters
Key Features & Advantages
🎯 Wide Frequency Coverage
30 MHz to 1 GHz continuous coverage with four precision-tuned baluns for optimal performance across the entire range
|
📐 Adjustable Elements
Telescoping elements allow precise tuning to ANSI C63.5 specified lengths for any frequency within the operating range
|
✅ Standards Compliant
Designed per ANSI C63.5 Appendix E reference antenna drawings, ensuring full compliance with international EMC standards
|
🔧 Durable Construction
High-quality materials with air-core inductors in baluns to prevent saturation and permeability variation
|
💼 Complete Kit
Includes all four baluns, complete element sets, tripod clamp, and rugged carrying case for transport and storage
|
📊 Known Antenna Factors
Antenna factors calculated per ANSI C63.5 specifications with verified balun loss for accurate measurements
|
Technical Specifications
General Specifications
| Parameter |
Specification |
| Model |
AD-100 V2.0 |
| Type |
Half-Wave Tuned Dipole Antenna Kit |
| Frequency Range |
30 MHz to 1 GHz |
| Maximum Input Power |
25 Watts (continuous) |
| Polarization |
Linear (Horizontal or Vertical) |
| Input/Output Impedance |
50Ω (nominal) |
| Antenna Factors |
-1.3 to 29.1 dB/m (nominal) |
| Isotropic Gain |
≈ 1 dBi (nominal) |
| VSWR |
<2.0:1 (average 1.5:1) |
| RF Connectors |
N-type (female) |
| Standards Compliance |
ANSI C63.4, ANSI C63.5, CISPR 16-1-4 |
Balun Frequency Ranges
| Balun Model |
Designation |
Frequency Range |
Typical Application |
| ABAL-AD100-DB1 V2.0 |
DB1 |
30 MHz to 65 MHz |
VHF Low Band, FM Radio |
| ABAL-AD100-DB2 V2.0 |
DB2 |
65 MHz to 180 MHz |
VHF High Band, TV Channels 2-6 |
| ABAL-AD100-DB3 V2.0 |
DB3 |
180 MHz to 400 MHz |
UHF Band, TV/Mobile Communications |
| ABAL-AD100-DB4 V2.0 |
DB4 |
400 MHz to 1 GHz |
UHF High Band, Cellular, ISM Bands |
Physical Specifications
| Parameter |
Specification |
| Overall Weight |
19.5 lbs (8.8 kg) |
| Minimum Element Length |
2.5 inches (63 mm) |
| Maximum Element Length |
109 inches (2777 mm) |
| Carrying Case Dimensions |
38.5" × 18" × 7.25" (978 × 457 × 184 mm) [W×D×H] |
Understanding Antenna Factors
The antenna factor (AF) is a critical parameter that relates the electric field strength at the antenna to the voltage at the antenna's output terminal. For the AD-100 V2.0 dipole antennas, antenna factors are calculated according to ANSI C63.5 specifications.
Antenna Factor Calculation
Per ANSI C63.5, the antenna factor for a theoretical "lossless" half-wave dipole is:
Lossless Dipole Factor (dB/m):
AF = 20 × log₁₀(freq. in MHz) - 31.4
However, real-world dipoles include balun losses. The ANSI standard specifies an averaged balun loss of 0.5 dB:
Actual Dipole Factor (dB/m):
AF = 20 × log₁₀(freq. in MHz) - 31.4 + 0.5
AF = 20 × log₁₀(freq. in MHz) - 30.9
How to Use Antenna Factors
For Receiving Applications (Field Strength Measurements):
Field Strength (dBμV/m) = Measured Voltage (dBμV) + Antenna Factor (dB/m)
For Transmitting Applications (EIRP Testing):
Isotropic Gain (dBi) = 20 × log₁₀(freq. in MHz) - 29.79 - Antenna Factor (dB/m)
Representative Antenna Factors by Frequency
| Frequency (MHz) |
Element Length (mm) |
Antenna Factor (dB/m) |
Isotropic Gain (dBi) |
Balun |
| 30 |
2413 |
-1.3 |
1.1 |
DB1 |
| 50 |
1438 |
3.1 |
1.1 |
DB1 |
| 100 |
714 |
9.1 |
1.1 |
DB2 |
| 200 |
352 |
15.1 |
1.1 |
DB3 |
| 400 |
175 |
21.1 |
1.2 |
DB3/DB4 |
| 600 |
117 |
24.7 |
1.1 |
DB4 |
| 900 |
79 |
28.2 |
1.1 |
DB4 |
| 1000 |
76 |
29.1 |
1.1 |
DB4 |
Real-World Applications & Use Cases
1. EMC Compliance Testing Laboratories
Scenario: FCC/CE Certification Testing
Challenge: A consumer electronics manufacturer needs to certify their new wireless router for FCC (United States) and CE (Europe) compliance before market release.
Application: The testing laboratory uses the AD-100 V2.0 dipole set to measure radiated emissions from the router across its operating frequencies.
Process:
- Device is placed in a semi-anechoic chamber or OATS
- Appropriate balun (DB1-DB4) is selected based on frequency being tested
- Elements are adjusted to exact ANSI C63.5 specified lengths
- Field strength measurements are made using calculated antenna factors
- Results are compared against regulatory limits
Why Dipole? ANSI C63.4 and CISPR standards specifically require dipole antennas for discrete frequency measurements during EMI compliance testing. No other antenna type is acceptable for official certification.
2. Test Site Validation and Calibration
Scenario: NSA Calibration of Anechoic Chamber
Challenge: A newly constructed semi-anechoic chamber must be validated to ensure it meets Normalized Site Attenuation (NSA) requirements before it can be used for official compliance testing.
Application: The AD-100 V2.0 serves as both the transmitting and receiving antenna for NSA measurements.
Process:
- Transmit dipole is positioned at one end of the chamber
- Receive dipole is positioned at the measurement distance (typically 3m or 10m)
- Measurements are performed at discrete frequencies across 30 MHz - 1 GHz
- Site attenuation is calculated and compared to theoretical values
- Chamber performance is validated against ANSI C63.4 requirements
Why Dipole? Dipoles are the only antennas with sufficiently predictable and calculable characteristics to serve as the reference for validating test site performance.
3. Broadband Antenna Calibration
Scenario: Calibrating a Log-Periodic Antenna
Challenge: An EMC laboratory has acquired a new log-periodic dipole array (LPDA) antenna and needs to determine its antenna factors.
Application: The AD-100 V2.0 is used as the reference antenna to calibrate the LPDA using the substitution method described in ANSI C63.5.
Process:
- A signal generator feeds a known signal to a transmit antenna
- The AD-100 dipole is used as the receive antenna and signal level is recorded
- The dipole is replaced with the LPDA at the same position
- Signal level is measured again with the LPDA
- LPDA antenna factor is calculated using the known dipole antenna factor
- Process is repeated at multiple frequencies across the operating range
Why Dipole? ANSI C63.5 specifically mandates that dipole antennas are the ONLY acceptable reference for calibrating broadband antennas.
4. Wireless Device Development
Scenario: RF Transmitter Power Verification
Challenge: An IoT device manufacturer is developing a new 915 MHz ISM band sensor and needs to verify transmit power doesn't exceed FCC limits.
Application: The AD-100 V2.0 with DB4 balun measures Effective Isotropic Radiated Power (EIRP) of the device during development.
Why Dipole? The known, calculable characteristics of the dipole provide accurate reference measurements without complex calibration procedures.
5. RFI Investigation
Scenario: Identifying Emission Source
Challenge: A manufacturing facility is experiencing intermittent interference with wireless communications at approximately 150 MHz.
Application: The AD-100 V2.0 with DB2 balun is used for field strength measurements to locate and quantify the interference source.
Why Dipole? The dipole's linear polarization and predictable pattern make it ideal for systematic field measurements and triangulation of interference sources.
6. Academic Research and Education
Scenario: University EMC Engineering Course
Challenge: Electrical engineering students need hands-on experience with antenna theory and EMC measurement techniques.
Educational Value:
- Students learn the relationship between frequency and wavelength by adjusting element lengths
- Practical experience with antenna factor calculations
- Understanding of standards-based testing procedures
- Hands-on calibration following ANSI C63.5
Why Dipole? The dipole's simplicity and well-understood theoretical basis make it the perfect teaching tool.
7. Military and Aerospace Testing
Scenario: MIL-STD-461 Compliance
Challenge: A defense contractor is developing avionics equipment that must meet stringent MIL-STD-461 radiated emissions requirements.
Application: The AD-100 V2.0 is used for RE102 (radiated emissions, electric field) testing.
Why Dipole? MIL-STD-461 references ANSI/CISPR standards which require dipole antennas for certain frequency ranges.
Why Choose the AD-100 V2.0?
Standards Compliance
The AD-100 V2.0 is designed following the exact Reference Antenna Example Drawings provided in Appendix E of ANSI C63.5. This means:
- Design is traceable to recognized international standards
- Test results are defensible in regulatory submissions
- Measurements are consistent with other accredited laboratories worldwide
- Full compliance with FCC, CE, VCCI, ISED Canada, and AS/NZS requirements
Manufacturing Quality Control
Every AD-100 V2.0 dipole kit undergoes rigorous quality verification:
- Balun Insertion Loss Verification: Each balun's insertion loss is individually measured and verified
- VSWR Testing: Elements tuned to resonance and VSWR measured at multiple frequencies
- Material Quality: High-grade materials ensure durability and long-term stability
- Air-Core Inductors: Prevents saturation and permeability variation
No Calibration Required
Per ANSI C63.4 and CISPR 16-1-4 standards, no calibration of half-wave dipoles is required beyond verification of balun loss and VSWR. Antenna factors are determined by calculation.
This provides significant advantages:
- Lower total cost of ownership (no periodic calibration fees)
- No downtime for calibration
- Immediate traceability through calculation
- Reduced measurement uncertainty
Note: NIST Traceable or ISO 17025 Accredited Calibration is available upon request.
Complete Kit Contents
| Part Number |
Description |
Quantity |
| ABAL-AD100-DB1 V2.0 |
Balun for 30-65 MHz |
1 |
| ABAL-AD100-DB2 V2.0 |
Balun for 65-180 MHz |
1 |
| ABAL-AD100-DB3 V2.0 |
Balun for 180-400 MHz |
1 |
| ABAL-AD100-DB4 V2.0 |
Balun for 400 MHz-1 GHz (with integral elements) |
1 |
| AELE-AD100V2-F3 |
300mm Fixed Extension Elements |
2 pieces |
| AELE-AD100V2-F7 |
700mm Fixed Extension Elements |
4 pieces |
| AELE-AD100V2-CL |
Collapsible Long Elements |
2 pieces |
| AELE-AD100V2-CS |
Collapsible Short Elements |
2 pieces |
| ATC-22M-AD |
Antenna Tripod Clamp - 22mm Rod |
1 |
| CASE-AD100 V2.0 |
Rugged Carrying/Storage Case |
1 |
Related Antenna Products
| Product |
Frequency Range |
Application |
| AB-900 Biconical |
20 MHz - 300 MHz |
Broadband VHF testing |
| AL-100 Log Periodic |
200 MHz - 1 GHz |
Broadband scanning |
| AH-118 Horn |
1 - 18 GHz |
Microwave EMC testing |
| AH-840 Horn |
18 - 40 GHz |
5G, automotive radar |
Ready to Get Started?
The AD-100 V2.0 is the essential reference standard for EMC testing laboratories worldwide.
Questions? Call (949) 459-9600 or email sales@com-power.com
19121 El Toro Rd., Silverado, California 92676
About Com-Power Corporation
Com-Power Corporation is a leading manufacturer of EMC test equipment, specializing in antennas, LISNs, current probes, and complete EMC test systems. With decades of experience serving test laboratories, manufacturers, and research institutions worldwide, Com-Power is committed to providing high-quality, standards-compliant test equipment backed by exceptional technical support.
All specifications subject to change without notice. All values are typical unless specified.
