Design of Multi-Scale Negative Group Delay Circuit for Sensors Signal Time-Delay Cancellation

This paper develops an innovative method of sensors' time-delay suppression. The proposed delay cancellation technique is highlighted with a theoretical concept and time-domain experimental demonstrations by using the negative group delay (NGD) function. The analytical investigation is elaborated with an NGD topology constituted by a simple active RC network. It is established theoretically that this active cell behaves like a low-pass NGD topology. The synthesis equations enabling to calculate the NGD cell parameters as a function of the desired NGD and gain are formulated. Frequency- and time-domain analyses showing the NGD function in multi-time scale are discussed. The NGD function verification is fulfilled with the design and fabrication of a proof-of-concept prototype. Nano-, micro-, and milli-second NGD effects are numerically and experimentally proved. As expected, time-domain experimental demonstrations showing arbitrary waveform signal in outstanding time-advance are realized. Moreover, the feasibility of the signal delay cancellation with 1- and 8-m length cables is experimented. The developed NGD time-delay cancellation demonstrations open the potential applications for the sensor performance improvement.