Helical Antenna Design Calculator and Formula

The Helical Antenna Design Calculator assists designers in computing key parameters of a helical antenna such as pitch angle, circumference, number of turns and resonant frequency. Helical antennas are popular for wideband communication and circular polarization.

EXAMPLE:

• INPUTS:

  • Operating Frequency in GHz (Freq) : 2.4
  • Number of Turns (N) : 10
  • Spacing Factor (S) : 0.25 (Will give spacing = 0.25 * λ)

• OUTPUT:

  • Antenna Gain, dB (output1) : 15.74
  • Diameter, meters (output2) : 0.0397
  • Half Power Beamwidth (HPW), Degrees (output3) : 32.88
  • Beamwidth first Nulls (BFN), Degrees (output4) : 72.73
  • Effective Aperture, Meter^2 (output5) : 0.0466

Helical Antenna Formula

Where,

• S = Spacing between turns
• N = Number of Turns
• C = circumference of coil
• F = Operating frequency of antenna under design
• λ = Wavelength = c/F, Where C = 3 x 10^8 m/s

Note : These formulas are for the normal (axial) radiation mode, common when C=λ (As specified for axial mode)

Benefits/Applications

• Speeds up design iterations: Engineers can quickly validate geometry against target frequency bands.
• Improves performance predictions: Helps anticipate impedance, gain, and bandwidth.
• Ideal for specialized applications: Used in satellite communications, GPS, and UHF/VHF systems.

Summary:

This calculator streamlines the design process for helical antennas by enabling accurate computation of geometric and electromagnetic parameters that correlate with performance.