Single CFOA-based active Negative Group Delay circuits for signal anticipation

Abstract

The group delay of a signal prior to data monitoring is a crucial consideration in today’s real-time applications, especially for those that involve long sensor arrays or high-order filters. In this article, nine new second-order Negative Group Delay (NGD) circuits based on Current Feedback Operation Amplifier (CFOA) are proposed, and their transfer functions are demonstrated. These circuits have a wide range of applications, from audio to mechanical signals and sensor signal anticipation. An example design procedure is provided for one of the introduced circuits. A time-domain analysis is performed using both a single-tone sinusoidal and a band-limited audio recording in the frequency range of 1 Hz to 500 Hz. The article assesses the change in the signal using Root Mean Square Error (RMSE) and cross-correlation. Furthermore, the relationship between the NGD value and the operation range of the circuit is investigated and verified experimentally. The results show that an NGD value of approximately 100μs can be achieved with an amplitude error of 0.86% for a single-tone input and 1.54% for an audio recording, and an operation range of about 650 Hz.

Keywords

• Audio signal processing
• Current feedback operation amplifier
• Design method
• Negative Group Delay
• NGD
• Time-domain validation