TY - GEN
T1 - 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
AU - Seo, Hyungjoo
AU - Zhou, Jin
N1 - Funding Information:
ACKNOWLEDGMENT This work was partially supported by NSF under the SpecEES program. The authors would like to thank Integrand EMX for electromagnetic simulation.
Publisher Copyright:
© 2020 IEEE.
PY - 2020/8
Y1 - 2020/8
N2 - This paper describes an agile RF front-end that consists of an N-path switched-LC mixer in silicon followed by an acoustic filter-essentially a mixer-first acoustic-filtering RF front-end. The mixer frequency-translates a sharp but fixed acoustic filtering profile to a much higher and LO-defined tunable frequency while preserves input matching, high-linearity, and introduces minimal loss. In contrast to the existing N-path passive-mixer-first receivers which use active baseband filters after N-path switches, using a single acoustic filter as the N-path load is fraught with fundamental challenges. We introduce on-chip LC-tanks to suppress the acoustic filter out-of-band impedance and an all-passive recombination network to share one acoustic filtering among N paths. A front-end prototype using a CMOS switched-LC passive mixer followed by an off-the-shelf 1.6-GHz surface-acoustic-wave (SAW) filter is designed and optimized. In measurement, the RF front-end operates across 2.5-to-4.5 GHz achieving 5.5-dB NF and +29.4-dBm IIP3 at 1×bandwidth offset.
AB - This paper describes an agile RF front-end that consists of an N-path switched-LC mixer in silicon followed by an acoustic filter-essentially a mixer-first acoustic-filtering RF front-end. The mixer frequency-translates a sharp but fixed acoustic filtering profile to a much higher and LO-defined tunable frequency while preserves input matching, high-linearity, and introduces minimal loss. In contrast to the existing N-path passive-mixer-first receivers which use active baseband filters after N-path switches, using a single acoustic filter as the N-path load is fraught with fundamental challenges. We introduce on-chip LC-tanks to suppress the acoustic filter out-of-band impedance and an all-passive recombination network to share one acoustic filtering among N paths. A front-end prototype using a CMOS switched-LC passive mixer followed by an off-the-shelf 1.6-GHz surface-acoustic-wave (SAW) filter is designed and optimized. In measurement, the RF front-end operates across 2.5-to-4.5 GHz achieving 5.5-dB NF and +29.4-dBm IIP3 at 1×bandwidth offset.
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U2 - 10.1109/RFIC49505.2020.9218392
DO - 10.1109/RFIC49505.2020.9218392
M3 - Conference contribution
AN - SCOPUS:85093924919
T3 - Digest of Papers - IEEE Radio Frequency Integrated Circuits Symposium
SP - 283
EP - 286
BT - RFIC 2020 - 2020 IEEE Radio Frequency Integrated Circuits Symposium
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2020 IEEE Radio Frequency Integrated Circuits Symposium, RFIC 2020
Y2 - 4 August 2020 through 6 August 2020
ER -