A phase meter with a switched-capacitor all-pass network as a controlled phase shifter within a feedback loop has been constructed. This phase meter works on the feedback compensation principle. Satisfactory operation of the device is possible, even if the signal is overwhelmed by noise and DC offsets, for the input phase range of - pi /2< Phi < pi /2 radians. The influence of noise and loop parameters on the phase jitter and acquisition time are studied using experimental results and by simulation.

V. S. Subramanian

K. M.Muraleedhara Prabhu

ALL PASS NETWORKS

Feedback loops

Switched capacitors

Capacitors

Computer simulation

performance

Phase shift

Phase Meters

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Performance of a compensating phase meter with a switched-capacitor all-pass network

Measurement Science and Technology

A novel phase meter with a switched capacitor phase shifter (SCPS) is described. This phase meter is a nonlinear feedback device and relies on the phase compensation principle. This works satisfactorily phase range - π/2 < ø < +π/2 under signal to noise ratios as low as -10 dB and DC offsets as high as the input signal-plus-noise peak in the signal channel. The influence of noise on the output phase noise is studied. Its steady state error curve is presented for two representative noise levels. © 1992, The Institution of Electrical Engineers. All rights reserved.

Electronics Letters

Novel phase meter using narrow pulse switched capacitor phase shifter

A feedback technique for phase sensitive detection (PSD) is developed, which is suitable for both synchronous and multiplier modes of implementation. The feedback-compensated PSD straightaway provides a dc output proportional to the amplitude of the measurand. The technique is very useful in a noisy environment where postprocessing of the in-phase and quadrature components would otherwise deteriorate the stability, accuracy, and sensitivity. © 1991 IEEE

IEEE Transactions on Instrumentation and Measurement

Feedback Compensated Synchronous and Multiplier Type Phase Sensitive Detectors

A circuit for constant phase shift using a narrow pulse duty cycle all-pass filter

Review of Scientific Instruments

Analog circuit for the measurement of phase difference between two noisy sine‐wave signals

Noise-proof phase meter with switched lowpass filters

Journal	Measurement Science and Technology
ISSN	09570233
Open Access	No