Radiation properties of quadrifilar-helix antenna - An analytical approach

An L-band four-element fractional-turn resonant helix antenna has been analyzed and designed for GPS receiver. Presented antenna is an electrically small (0.3λ in axial length and 0,18 in diameter), provided circular polarization over a broad angular region, and hemispherical radiation pattern. Integral formulas for the radiated E-field have been derived and computed, shoving good agreement with the measured data.