Study On Wave Spectra Inversion Technology Based On Mother-Son Buoys

Improve the capability of waves' observation and forecasting, and minimize the devastating loss caused by the ocean wave, is one of the important goals of high-tech development of marine monitoring in our country. The more accurate grasp of ocean wave is a universal problem. Based on the known characteristic study of irregular ocean waves, this paper put new technical ideas to solve the technical problems by combining random process analysis, nonlinear system analysis and the latest results of wavelet theory.This paper proposed wave-measuring method by using mother-son buoy arrays. The buoy array is made of the mother and four buoys which are symmetric distribution. The mother buoy is fixed in the seabed by chain, and son buoys do not link to the seabed, and only through the hinge connecting rod to the mother buoy. In the role of the waves, the son buoys move along the center axis around the mother buoy, and there is no motion between the mother buoy and the son ones. And their relative position is fixed. In addition, the son buoys are not linked to the seabed, which has a very good floating performance, and can be able to test some of the high-frequency wave form. It is due to the use of mother-son structure, it greatly reduces the mooring force to the son buoys, so the son buoys can move with waves better. In addition, the son buoys have small size, the quality being relatively small, the flowability and the measurement accuracy of the system can be enhanced.With given algorithm, it has analyzed the force on the buoy and mooring system. Based on real data, put forward a sort of new sea wave inversion spectra, and compare it with the true one, it is found that the spectrum can be a good approximation of the measured spectra, and it. has smooth curves and the error is very small, parameter-confirmation is simple and the computing amount of is small. And further, under the same condition, comparing the new inversion spectra with PM spectra and WEN spectra, then found it was close to them. Simulate ocean wave by the new spectra, construct ocean wave function generator, and found it's fast Fourier results are accord with our ocean, and again this proved the new spectra is valid.Using spectral analysis, it analyzed the statistical properties of the waves. Wave spectrum is the basic method to describe the waves. In oceanography, using spectral analysis as a random process to describe the waves is one of the main study. It is based on the internal composition- wave concept to describe the distribution of the waves average energy in the internal wave number space or frequency, it can not only reveal the internal structure of the waves, but also to provide the appearance of the demographic characteristics of the waves, therefore, the and the wave spectrum research remains the central issue.Based on wavelet theory, the paper put forward the energy-adaptive threshold algorithms, and used it to do time-frequency analysis on the waves, and made full use of the Fourier transform high-resolution in the frequency domain. Combined the wavelet transform with Fourier Transform, it analyzed the inherent non-linear, non-steady-state properties of the ocean wave deep.As the specific realization form of the waves measuring system, the paper designed the mother-son waves measuring system with high flowability, based on MEMS accelerometer. It has the following characteristic: a small size, light weight, high accuracy. The detailed design was carried out from the stabilization, safety, reliableness to ultra-low power, high flowability.