A Quadrature Balanced N-Path Receiver for Frequency Division Duplex With Thermal and Phase Noise Cancellation Under Antenna VSWR

• Published in: IEEE transactions on microwave theory and techniques Vol. 72; no. 6; pp. 3468 - 3475
• Main Authors: Zolkov, Erez, Cohen, Emanuel
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.06.2024; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antennas; Frequency division duplexing; Frequency division duplexing (FDD); Interference cancellation; Microwave filters; Mixers; N-path filter; Noise levels; Noise measurement; Phase noise; Power consumption; quadrature balanced N-path receiver (QBNR); Quadratures; Reflector antennas; self-interference cancellation (SIC); Thermal noise; Voltage standing wave ratios
• ISSN: 0018-9480; 1557-9670
• DOI: 10.1109/TMTT.2023.3328037

In this work, we propose a frequency division duplexing (FDD) transceiver front-end (TFE) capable of canceling both the transmitter (TX) noise and reciprocal mixing (RM), under antenna voltage standing wave ratio (VSWR) variations. The TFE is composed of a quadrature balanced <inline-formula> <tex-math notation="LaTeX">N </tex-math></inline-formula>-path receiver (QBNR) with the addition of a coupled auxiliary path to cancel reflected RM from the antenna. A discrete implementation incorporating two-port <inline-formula> <tex-math notation="LaTeX">N </tex-math></inline-formula>-path (TPNP) filters manufactured in TSMC CMOS 65 nm is shown. Measurements of the proposed TFE show more than 27-dB TX noise cancellation, with NF of 6-7 dB in the presence of a 5-dBm modulated TX blocker, under VSWR of 2:1 and equal thermal and RM noise floors of −147 dBm/Hz, with power consumption of 57 mW at a 1.5-GHz local oscillator (LO) frequency.