Feasibility Study of Multistage Low‐Pass NGD Circuit Design Methodology Using RL‐Network

ABSTRACT The negative group delay (NGD) circuit is uniquely capable of propagating arbitrary waveform signals with time advancement. Achieving significant NGD performance in practical applications, however, requires a multistage design approach. This article develops a design methodology for multistage low‐pass (LP) NGD circuits based on RL‐networks. After recalling the theoretical design equations enabling the determination of the multistage LP‐NGD parameters based on the desired time advance and signal bandwidth, a design flow methodology is introduced. As proof‐of‐concept, a feasibility study of a multistage LP‐NGD circuit, designed for a time advance of −100 ms, is conducted using a three‐stage printed circuit board (PCB) consisting of RL‐cells. Simulations in both the frequency and time domains confirm that the fabricated PCB prototype can propagate different waveform signals as expected, demonstrating the LP‐NGD properties. Time‐advance measurements with the PCB prototype further validate these LP‐NGD effect findings. The proposed multistage design methodology provides a promising solution for addressing signal delay issues and offers new opportunities for innovative signal processing applications in future electronic systems.