TECHNICAL MECHANICS
|
![]() |
|||||
|
||||||
![]() |
Home
>
Journal Issues
>
¹ 4 (2014) Technical mechanics
>
8
___________________________________________________ UDC 621.002.56 Technical mechanics, 2014, 4, 85- 93 MOTION SENSING BY A TWO-PROBE IMPLEMENTATION OF MICROWAVE INTERFEROMETRY Pylypenko O. V.,. Gorev N. B, Doronin A. V., Kodzhespirova I. F.
This paper addresses the possibility of displacement measurement by microwave interferometry
at an unknown reflection coefficient with the use of two probes mounted in a waveguide
section. The aim of this paper is to show that the displacement measurement accuracy
can be improved by using an interprobe distance other than its conventional value.
The case of an arbitrary interpobe distance is considered. The measurement error
as a function of the interprobe distance and the reflection coefficient is analyzed
with the inclusion of variations of the currents of the semiconductor detectors connected
to the probes from their theoretical values. The analysis has shown that as the interprobe
distance decreases, the measurement error passes through a minimum for reflection coefficients
close to unity and increases monotonically for smaller reflection coefficients. This behavior
of the error is due to the fact that with decreasing interprobe distance and/or reflection
coefficient the inherent error of two-probe measurements decreases, while the error caused
by variations of the detector currents from their theoretical values increases. The interprobe
distance is suggested to be one tenth of the guided operating wavelength ?g. In comparison
with the conventional interprobe distance of ?g/8, the suggested value offers a marked
reduction in the measurement error for reflection coefficients close to unity, while
for smaller ones this error increases only negligibly. This is verified by experiment using
both free-space and waveguide measurements. The results reported in this paper may be used
in the development of microwave displacement sensors for various classes of vibration
protection and workflow control systems.
vibration, displacement, interferometry, probe, incident wave, reflected wave, semiconductor detector, detector current
1. Viktorov V. A. Radiowave Measurements of Process Parameters (in Russian) / V. A. Viktorov, B. V. Lunkin, A. S.Sovlukov – Moscow: Energoatomizdat, 1989. – 208 p.
Copyright (©) 2014 Pylypenko O. V.,. Gorev N. B, Doronin A. V., Kodzhespirova I. F. Copyright © 2014-2018 Technical mechanics ____________________________________________________________________________________________________________________________ |
GUIDE FOR AUTHORS ![]() |