Aperture analysis of group delay measurement based on spread spectrum modulation

Modulation method is a series of effective approach for group delay measurement, especially in applications of Frequency-Translating Devices (FTD). The spread spectrum modulation approach has the advantages of precision and robustness by using correlation operation to obtain the relative delay. In this paper, the aperture of this method is discussed based on the measurement principle and an improved measurement approach is proposed. The digital simulations prove the effectiveness of the improved approach.