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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)
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)
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)
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 formulates various quality () factors associated with the applications of on-chip spiral inductors to radio-frequency integrated circuits using-parameters. The formulations start with the factor of a spiral inductor in a generalized two-port configuration based on a new complex-power approach and then extend to the factors of a tank and matching(More)
The envelope elimination and restoration (EER) approach developed by Kahn and its modern derivative, a polar transmitter, are well recognized as highly efficient amplification schemes. This paper presents an EER/polar dual-mode transmitter using injection-locked oscillators (ILOs). For an EER operation, an ILO that is combined with a mixer and a low-pass(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)
This work presents a wireless system that operates in the 2.4 GHz ISM band for concurrently sensing the vital signs and positions of multiple individuals. Characterized by low complexity and high accuracy, the proposed system consists of two main parts. One is a self-injection-locked (SIL) tag carried by a subject, which emits a sinusoidal(More)