Instantaneous frequency measurement based on low-cost Six-Port technology

This paper describes a new approach for absolute, high accuracy and fast responding millimeter wave frequency measurement. The shown system is based on the reduction of the frequency detection to a phase measurement with a delay line and a subsequent determination of the phase. By using a Six-Port structure, this phase can be evaluated very precisely, leading to a accurate frequency detection. Another remarkable point is the fast system response, because there is neither time consuming transformation to frequency domain nor long integration time required.