We use time-variance as a circuit-design toolbox to design novel RF circuits ranging from filters to non-reciprocal devices. In this project, we focused on designing high frequency RF filters using baseband load-modulated N-path filters to achieve high-Q, wide tunability, and high out-of-band rejection. In one of our recent work, that was published in ISSCC 2023 and IEEE JSSC 2023, a frequency-translational RF N-path filter is designed exploiting the inherent frequency conversion of an N-path filter to implement the intermediary filter nodes in a higher order filter at baseband for 1GHz- 5GHz applications. N-path elliptical low-pass filter (LPF) is used for filtering the baseband signal, which is implemented mosfet switches and capacitors (without inductor) making it area efficient and highly suitable for CMOS technology implementation.
Recent publications:
- Nagulu, A., Zhuang, Y., Yuan, M., Garikapati, S. and Krishnaswamy, H., 2023. A Third-Order Quasi-Elliptic N-Path Filter With Enhanced Linearity Through Clock Boosting. IEEE Journal of Solid-State Circuits.
- Nagulu, A., Yi, M., Zhuang, Y., Garikapati, S. and Krishnaswamy, H., 2023, February. A 1-to-5GHz All-Passive Frequency-Translational 4 th-Order N-path Filter with Low-Power Clock Boosting for High Linearity and Relaxed Pdc-Frequency Trade-Off. In 2023 IEEE International Solid-State Circuits Conference (ISSCC) (pp. 378-380). IEEE.