Frequency-Domain Analysis of Super-Regenerative Amplifiers

• Main Authors: Dawson, Joel L. (Contributor), Bohorquez, Jose L. (Contributor), Chandrakasan, Anantha P. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science (Contributor), Massachusetts Institute of Technology. Microsystems Technology Laboratories (Contributor)
• Format: Article
• Language: English
• Published: Institute of Electrical and Electronics Engineers, 2010-10-07T14:53:32Z.
• Subjects: Article
• Online Access: Get fulltext

 Since its invention in 1922, the super-regenerative amplifier (SRA) has been used in a variety of short-range, low-power, and/or low-cost wireless systems due to its simple implementation and excellent performance for a given power budget. Growing demand for ultralow-power receivers for short-range radios has recently reawakened an interest in the theory and design of SRAs. Building on recent work and using reasonable assumptions and approximations, we present a frequency-domain model for analyzing SRAs. We then use these models to predict the response of an SRA to arbitrary deterministic and stochastic signals including sinusoids, pulsed-sinusoids, and additive white Gaussian noise. Using the results, we present formulas for calculating the sensitivity and selectivity of SRAs. We also introduce the concept of a trigger-time that is particularly useful for accurately determining the optimal threshold in on-off keying (OOK) receivers and helps avoid the problems introduced by nonlinearity in SRAs. Finally, we present a prototype OOK SRA that achieves a sensitivity of -90 dBm at a bit rate of 300 kbps (BER of 10[superscript -3]) while consuming 500 muW, and show that its measured sensitivity matches theory within 1 dB.