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This work presents a single-antenna self-injection-locked (SIL) radar to reduce the hardware complexity of continuous-wave (CW) Doppler systems. The theory provides a basis for determining the signal-to-noise spectral density ratio (SNDR) with the effects of clutter. Experimental results agree closely with the theoretical predictions, showing that the(More)
A novel RF sensing circuit for a cognitive radio to sense spectral environment is proposed using injection locking and frequency demodulation techniques. The research starts with deriving a generalized locking equation for oscillators as a theoretical basis, and then develops the sensing principle and circuit architecture to a practical and useful level. To(More)
Elucidating how local oscillator (LO) pulling affects a wireless direct-conversion transmitter that uses constant envelope modulation is of concern for global system for mobile communication (GSM). Therefore, this paper presents a phase dynamic model for a phase-locked loop (PLL) under directly modulated self-injection to evaluate the degraded phase noise(More)
This paper presents a self-injection-locked (SIL) radar with ranging and tracking capabilities to see through walls for discovering hidden people. Characterized by low complexity and high sensitivity, the proposed SIL radar merges the frequency-modulated continuous-wave and sum-difference pattern detection approaches to determine the distance and azimuth(More)
A novel vital-sign sensor with a self-injection-locked oscillator and a frequency demodulator to reduce system complexity and improve sensitivity is proposed. The theory provides a delta-sigma model to account for the excellent signal-to-noise spectral density ratio in a parametric study of the sensitivity performance. Then, the experiments verify the(More)
This work designs and implements a wideband common-gate (CG) low-noise amplifier (LNA) with dual-feedback using 0.18 &#x00B5;m CMOS technology. The design is based on a mechanism of dual-feedback, which is composed of a transformer and a g<inf>m</inf>-boosting feedback, to overcome the trade-off between noise and input matching in common-gate topology(More)
This paper presents design and linearization techniques for a highly efficient, but nonlinear Class-E power amplifier (PA) applied to linear RF transmitters. To achieve maximum efficiency for Class-E PA operating above gigahertz frequencies, the proposed design theory modifies the classic Class-E condition and considers switch-on and switch-off resistances(More)
This paper presents two CMOS common-gate (CG) low-noise amplifiers (LNAs) using different dual-feedback techniques, significantly reducing noise figure (NF) to around 2 dB over a wide frequency range. The proposed first CG LNA uses gm-boosted feedback and shunt-series transformer feedback to relieve the tradeoff between input and noise matching. The(More)
This study presents injection-pulling effects on a local oscillator (LO) for wireless applications. A discrete-time analysis is provided to predict output spectra of the LO pulled by a sinusoidal and angle-modulated injection signal. A phase-locked loop synthesizer with an injection signal is analyzed in frequency domain to account for the inherent bandpass(More)