This paper presents a novel technique for suppression of in-band artifacts from out-of-band (OOB) interference in widely tunable RF receivers. The technique employs a multi-tap inductor-capacitor network (LCN) to generate diversity in gain and phase between taps across the targeted frequency range. Using this network to feed a bank of identical receivers sharing a single local oscillator (LO) allows multiple kinds of interferer artifact to be suppressed. Here we considered spur-induced and phase noise-induced artifacts. In each case, the resulting artifacts are linearly separable from signal when the outputs of the sub-receivers are recombined. AC and transient simulations were first performed to show feasibility of the proposed approach. A prototype was implemented in 45nm CMOS which confirmed the validity of the synthetic diversity (SD) approach for suppressing interferer artifacts, showing a maximum lowering in EVM and BER of 38% and 60% respectively.
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Synthetic Diversity To Mitigate Out-of-Band Interference in Widely Tunable Wireless Receivers
Here we present a combined RF hardware/DSP technique to synthesize effective channel diversity in single-antenna wireless systems. This allows digital suppression of out-of-band interference artifacts in widely tunable wireless receivers with one or more antennas, including artifacts from LO phase noise. A passive inductor-capacitor (LC) network provides gain and phase diversity between channels and across frequency. Since amplitude and phase of in-band artifacts are set by the amplitude and phase of the out-of-band interference that generates them, they can be suppressed in DSP without knowledge about the interferer itself. The feasibility of this approach is demonstrated mathematically, with numerical system simulations, and full circuit simulation.
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- Award ID(s):
- 1641100
- NSF-PAR ID:
- 10206914
- Date Published:
- Journal Name:
- Synthetic Diversity To Mitigate Out-of-Band Interference in Widely Tunable Wireless Receivers
- Volume:
- 53
- Page Range / eLocation ID:
- 774 to 778
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/IEEECONF44664.2019.9048662
