A Cost-Effective Geodetic Strainmeter Based on Dual Coaxial Cable Bragg Gratings
نویسندگان
چکیده
Observations of surface deformation are essential for understanding a wide range of geophysical problems, including earthquakes, volcanoes, landslides, and glaciers. Current geodetic technologies, such as global positioning system (GPS), interferometric synthetic aperture radar (InSAR), borehole and laser strainmeters, are costly and limited in their temporal or spatial resolutions. Here we present a new type of strainmeters based on the coaxial cable Bragg grating (CCBG) sensing technology that provides cost-effective strain measurements. Two CCBGs are introduced into the geodetic strainmeter: one serves as a sensor to measure the strain applied on it, and the other acts as a reference to detect environmental noises. By integrating the sensor and reference signals in a mixer, the environmental noises are minimized and a lower mixed frequency is obtained. The lower mixed frequency allows for measurements to be taken with a portable spectrum analyzer, rather than an expensive spectrum analyzer or a vector network analyzer (VNA). Analysis of laboratory experiments shows that the strain can be measured by the CCBG sensor, and the portable spectrum analyzer can make measurements with the accuracy similar to the expensive spectrum analyzer, whose relative error to the spectrum analyzer R3272 is less than ±0.4%. The outputs of the geodetic strainmeter show a linear relationship with the strains that the CCBG sensor experienced. The measured sensitivity of the geodetic strainmeter is about -0.082 kHz/με; it can cover a large dynamic measuring range up to 2%, and its nonlinear errors can be less than 5.3%.
منابع مشابه
Optical pulse compression based on nonlinear silicon waveguides and chirped Bragg gratings
Due to the growing demand for higher bandwidth, employing optical devices instead of electronic devices in data transmission systems has attracted much attention in recent years. Optical switches, modulators and wavelength converters are a few examples of the required optical devices. CMOS compatible fabrication of these devices, leads to much more growing of this technology. Optical pulse comp...
متن کاملTunable all-optical negative multitap microwave filters based on uniform fiber Bragg gratings.
We present a novel and simple technique for obtaining transversal filters with negative coefficients by using uniform fiber Bragg gratings. We demonstrate a wide tuning range, good performance, low cost, and easy implementation of multitap filters in an all-optical passive configuration in which negative taps are obtained by use of the transmission of a broadband source through uniform Bragg gr...
متن کاملLong-period Surface Waves of Four Western United States Earthquakes Recorded by the Pasadena Strainmeter by Diane I. Doser and Hiroo Kanamori
Long-period surface waves recorded on the north-south Pasadena strainmeter are used to determine the seismic moments and fault parameters of the 19 May 1940 Imperial Valley, California, the 16 December 1954 Dixie Valley and Fairview Peak, Nevada, and the 18 August 1959 Hebgen Lake, Montana, earthquakes. Synthetic strain seismograms are matched with the observed strainmeter seismograms. Source p...
متن کاملDual Space Control of a Deployable Cable Driven Robot: Wave Based Approach
Known for their lower costs and numerous applications, cable robots are an attractive research field in robotic community. However, considering the fact that they require an accurate installation procedure and calibration routine, they have not yet found their true place in real-world applications. This paper aims to propose a new controller strategy that requires no meticulous calibration and ...
متن کاملFiber Bragg Gratings for In-line Dispersion Compensation in Cost-effective 10.7-Gbit/s Long-Haul Transmission
Among the promising new developments towards cost-effective long-haul transmission are chirped multi-channel Fiber Bragg Gratings (FBG). In this paper we discuss the feasibility of long-haul WDM optical transmission using only FBGs for in-line dispersion compensation. We show successful transmission of 32x10.7-Gbit/s NRZ modulated channels over 3,800-km using low group delay ripple slope-matche...
متن کامل