Estimation of the Losses of 1:N Dividers by the Measurement of the Reflection When the Outputs Are Shorted

Starting from the input reflection coefficient of a 1:N divider/corporate-feed antenna, measured when the outputs are short-circuited, a method is proposed to estimate its losses. When the outputs are in phase, as typically occurs in beam forming network applications, the relationship between such an input reflection coefficient and losses is straightforward and variation of reflection with frequency is smooth. When the phases are different from one another, the input reflection coefficient is always smaller than above and oscillates with frequency. The oscillation amplitudes strongly depend on the phase imbalance and, in some cases, reflection can tend to zero. Nonetheless, it will be shown that a preliminary estimation of the losses is still possible.