Thrust 1: Broadband Delay-based RF Signal Processing
Unlike existing LPTV switched-capacitor broadband delays, the introduction of inductors in our proposed commutated-LC delay circuit provides a new degree of freedom, allowing it to operate at a much higher RF with a wider instantaneous bandwidth [JSSC2020]. In [RFIC2022], we introduce negative resistance to compensate inductor loss in our commutated-LC broadband delay circuit, and unveils a new capability of time-varying RF circuits that we call harmonic power recycling.
- [JSSC2022] S. Ming, J. Yang, and J. Zhou, "A Commutated-LC RF Broadband Delay Circuit," accepted to IEEE Journal of Solid-State Circuits (JSSC), early access, published in April 2022.
- [RFIC2022] S. Ming, R. Islam, and J. Zhou, "A C-Band Commutated-LC-Negative-R Delay Circuit with Harmonic Power Recycling Achieving 1.5-ns Delay, 1.4-GHz BW, and 6-dB IL," in Proc. 2022 IEEE Radio Frequency Integrated Circuits (RFIC) Symposium, Denver, CO, USA, 2022.
Thrust 2: Mixer-First Acoustic-Filtering Architecture
In an existing multi-band RF front end, a bank of acoustic filters with different center frequencies connects to an antenna via a static RF switch and matching networks (MN). This approach requires numerous different filters and lacks flexibility to incorporate future frequency bands after field deployment. Our design effectively makes the RF switch periodically rotate among a bank of identical filters, making the input frequency programmable and defined by the commutation frequency.
- [TMTT2022] H. Seo, M. Sha, and J. Zhou, "A Passive-Mixer-First Acoustic-Filtering Chipset Using Mixed-Domain Recombination," accepted to IEEE Transactions on Microwave Theory and Techniques (TMTT), early access, published in March 2022. (RFIC 2021 special issue)
- [JSSC2021] H. Seo and J. Zhou, "A Passive-Mixer-First Acoustic-Filtering Superheterodyne RF Front-End," in IEEE Journal of Solid-State Circuits (JSSC), vol. 56, no. 5, pp. 1438-1453, May 2021. (Invited Paper)
- [RFIC2021] H. Seo, M. Sha, and J. Zhou, , "A 3.5-to-6.2-GHz Mixer-First Acoustic-Filtering Chipset with Mixed-Domain Asymmetric IF and Complex BB Recombination Achieving 170 MHz BW and +27 dBm IIP3 at 1xBW offset," in Proc. 2021 IEEE Radio Frequency Integrated Circuits (RFIC) Symposium, Atlanta, GA, USA, 2021.
- [RFIC2020] H. Seo and J. Zhou, “A 2.5-to-4.5-GHz Switched-LC-Mixer-First Acoustic-Filtering RF Front-End Achieving <6dB NF, +30dBm IIP3 at 1×Bandwidth Offset”, in Proc. 2020 IEEE Radio Frequency Integrated Circuits (RFIC) Symposium, Jun. 2020.
Thrust 3: Adaptive Self-Interference Cancellation for Full-Duplex MIMO
We co-design commutated-capacitor-based self-interference canceller and its adaptation circuitry, demonstrating self-adaptive broadband self-interference cancellation in [IMS2020,RFIC2019]. Leveraging our proposed self-adaptive interference cancellation technology, we have extended integrated full-duplex radio operation towards power-scalable multi-in-multi-out (MIMO) wireless in [JSSC2020].
- [JSSC2020] Y. Cao and J. Zhou, "Integrated Self-Adaptive and Power-Scalable Wideband Interference Cancellation for Full-Duplex MIMO Wireless," in IEEE Journal of Solid-State Circuits (JSSC), vol. 55, no. 11, pp. 2984-2996, Nov. 2020.
- [IMS2020] Y. Cao, X. Cao, H. Seo, and J. Zhou, “An Integrated Full-Duplex/FDD Duplexer and Receiver Achieving 100MHz Bandwidth 58dB/48dB Self-Interference Suppression Using Hybrid-Analog-Digital Autonomous Adaptation Loops”, in Proc. 2020 IEEE International Microwave Symposium (IMS), Jun. 2020.
- [RFIC2019] Y. Cao and J. Zhou, "A CMOS 0.5-2.5GHz Full-Duplex MIMO Receiver with Self-Adaptive and Power-Scalable RF/Analog Wideband Interference Cancellation," in Proc. 2019 IEEE Radio Frequency Integrated Circuits (RFIC) Symposium, Boston, MA, USA, 2019, pp. 147-150.