Estimate of embedded element efficiency using S-parameter measurements

S-parameter measurements are used to obtain impedance mismatch and coupling loss of radiating elements embedded in an array configuration. This paper shows how the measurements can be used independently of element pattern measurements to estimate the array element efficiency. The method is extended to the array antenna efficiency by synthesizing the active S-parameter coefficients assuming uniform excitation. Utilizing S-parameter measurements as a first estimate of the array antenna efficiency offers an efficient and cost-effective method which only requires a network analyzer.