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Recent advancements in low power and low noise front-end amplifiers have made it possible to support high-speed data transmission within the deep roll-off regions of conventional wireline channels. Despite being primarily limited by inter-symbol-interference (ISI), these legacy channels also require power-consuming front-end amplifiers due to increased insertion-loss at high frequencies. Wireline-like broadband channels, such as proximity communication and human-body-communication (HBC), as well as multi-lane, densely-packed channels, are further constrained by their high loss and unique channel responses which cause the received signal to be noise-limited. To address these challenges, this paper proposes the use of a discrete-time integrating amplifier as a low power <1 pJ/b using 65nm CMOS up to 5-6 Gb/s) alternative to traditional continuous-time front-end amplifiers. Integrating amplifiers also reduce the effects of noise due to its inherent current integrating process. The paper provides a detailed mathematical analysis of gain of two conventional and three novel and improved integrating amplifiers, accurate input referred noise estimations, signal-to-noise ratio, and a comparison of the integrating amplifier’s performance with that of a low-noise amplifier. The analysis identifies the most optimum integrator architecture and provides comparison with simulated results. This paper also develops theoretical expressions and provides in-depth understanding of input referred noise, while supporting them by simulations using 65nm CMOS technology node. Finally, a comparative analysis between low-noise amplifier and discrete-time integrating amplifier is presented to demonstrate power and noise benefits for both legacy and wireline-like channels, while providing an easier design space as integrator provides two-dimensional controllability for gain.
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A Parametric MEMS Oscillator-Based Super-Regenerative Receiver Front-End
The use of parametric oscillator start-up principles applied to a MEMS-based super-regenerative receiver front-end obviates the need for a positive feedback sustaining amplifier and permits OOK input detection with sensitivity better than −67 dBm using only 15 µW of pump power, which is 33 times smaller than the previous published mark of 490 μW using MEMS [1]. Here, removal of the sustaining amplifier (and its 489 μW) and instigation of oscillator start-up via parametric means permit use of a much lower power oscillator, e.g., a ring oscillator, to pump the RF front-end detecting resonator at double its resonance frequency while retaining acceptable receiver sensitivity. The substantial reduction in power consumption afforded by this method is compelling for IoT applications, where power is paramount, especially for wireless communications.
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- Award ID(s):
- 1809319
- PAR ID:
- 10145359
- Date Published:
- Journal Name:
- 2019 IEEE International Frequency Control Symposium
- Page Range / eLocation ID:
- 1 to 5
- 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/FCS.2019.8856028
