54 results about "Wavelet processing" patented technology

Carrier Interferometry (CI) provides wideband transmission protocols with frequency-band selectivity to improve interference rejection, reduce multipath fading, and enable operation across non-continuous frequency bands. Direct-sequence protocols, such as DS-CDMA, are provided with CI to greatly improve performance and reduce transceiver complexity. CI introduces families of orthogonal polyphase codes that can be used for channel coding, spreading, and / or multiple access. Unlike conventional DS-CDMA, CI coding is not necessary for energy spreading because a set of CI carriers has an inherently wide aggregate bandwidth. Instead, CI codes are used for channelization, energy smoothing in the frequency domain, and interference suppression. CI-based ultra-wideband protocols are implemented via frequency-domain processing to reduce synchronization problems, transceiver complexity, and poor multipath performance of conventional ultra-wideband systems. CI allows wideband protocols to be implemented with space-frequency processing and other array-processing techniques to provide either or both diversity combining and sub-space processing. CI also enables spatial processing without antenna arrays. Even the bandwidth efficiency of multicarrier protocols is greatly enhanced with CI. CI-based wavelets avoid time and frequency resolution trade-offs associated with conventional wavelet processing. CI-based Fourier transforms eliminate all multiplications, which greatly simplifies multi-frequency processing. The quantum-wave principles of CI improve all types of baseband and radio processing.

The invention relates to a ghost wave compression method based on wavelet processing. The method comprises the steps that (1) offshore seismic data information are input, wherein the seismic data information comprises three kinds of seismic wavelets and seismic data comprising uncompressed ghost waves, and the three kinds of seismic wavelets comprise the seismic wavelet comprising cable ghost waves and seismic source ghost waves, the seismic wavelet comprising the seismic source ghost waves only and the seismic wavelet comprising no ghost waves; (2) ghost wave compression is carried out on seismic data with uncompressed ghost waves through the seismic wavelets; (3) seismic data which compress the cable ghost waves and the seismic source ghost waves at the same time are output. According to the ghost wave compression method, the wavelet matching algorithm is adopted for compressing the ghost waves, and the ghost waves are compressed starting from seismic data processing instead of collection, so that the processing process is easy to implement, and the cost is saved; the ghost wave compression method can compress the seismic source ghost waves and the cable ghost waves in the offshore seismic data, and can be widely applied in the offshore seismic exploration process.

It is an object of the present invention to prevent an image distortion from occurring by using a line memory of small memory capacity. For example, an image is decomposed into strip regions 12, and each strip region 12 is filtered together with certain excess data 14 from a neighboring strip region 12 to prevent an image distortion from occurring at the boundary between the strip regions 12 while executing band decomposition on the strip region 12 which is smaller in size than the entire image with a smaller line memory. In the band decomposition, a line memory which supports band decomposition of, for example, 3 decomposition levels is repeatedly and recursively used, whereby band decomposition of deeper decomposition levels is executed without any problems. In this manner, line-based wavelet transform for deeper decomposition levels is executed with a small line memory. Also reverse wavelet transform is executed in the similar manner.

A laser phase Doppler dust particle monitoring method and apparatus belongs to particle measuring technique. It includes the steps that two beams of coherent incident light has concourse and irradiate normally to flowing direction of dust particle current; two sensors are installed with symmetry, optical signal of particle scattering received by which has the same frequency but different phase, its frequency is proportional to flight velocity of particle and phase difference is proportional to with diameter of particle, by using processor to extract frequency and phase difference of signal, the diameter, velocity and other information of particle are obtained. The apparatus consists of detecting system containing laser source, polarizer, beam splitter, objective lens and APD sensor and processing system containing signal preprocessor, high speed synchronous A / D converter, wavelet processor, parameter processor and data fractional, synchronous controller. The invention has the advantages including high accuracy and reliability of parameter measurement like velocity and diameter of dust particle, wide measuring range and excellent applicability.

The invention discloses an aero-engine blade test piece nondestructive testing method based on a terahertz technology, which comprises the following steps: performing nondestructive testing on a sample by utilizing a terahertz signal to obtain a terahertz original detection signal; carrying out fourier transform, frequency domain deconvolution and wavelet processing on the terahertz original detection signal to obtain a characteristic signal with a high signal-to-noise ratio; performing Fourier transform on the characteristic signal with the high signal-to-noise ratio to obtain a frequency domain power spectrum, and expanding the frequency domain power spectrum to obtain a sample image; and carrying out quantitative characterization on the thickness and defects of the ceramic layer in thesample image after the imaging contrast is improved. The invention further provides an aero-engine blade test piece nondestructive testing device based on the terahertz technology. According to the method, the problems of low detection precision, limited detection range and missed detection and false detection of a traditional nondestructive detection mode can be solved, and high-precision quantitative detection of the surface, interface and internal crack defects of the thermal barrier coating and the thickness of the ceramic layer is realized.

The invention discloses a face recognition method under complicated illumination conditions of an underground coal mine. The method mainly comprises an initialization stage, a training stage and a recognition stage, wherein image collection, image storage, image denoising, image enhancement and feature description are included at the initialization stage, feature vector dimension reduction and classifier model establishment are included at the training stage, and classified recognition is performed on to-be-recognized faces according to an established classifier model at the recognition stage;and image denoising and image enhancement are realized by the adoption of a fuzzy enhancement algorithm based on wavelet decomposition, an ALBP operator is adopted to perform feature description on aface image after wavelet processing, and a classifier is adopted to construct a face model and establish a face sample database. Through the method, the problem that the recognition rate is sharply lowered due to image shadows, bright and dark areas, dark light and high light under complicated underground illumination conditions can be overcome, and the face attendance recognition accuracy in theunderground coal mine is improved.

A process for secured distribution of video sequences according to a digital stream format stemming from an encoding based on a processing by wavelets including frames including blocks containing coefficients of wavelets describing the visual elements, including analyzing the stream prior to transmission to client equipment to generate a modified main stream by deletion and replacement of selected information coding the original stream and having the format of the original stream, and complementary information of any format comprising the digital information coding the original stream and suitable for permitting reconstruction of the modified frames; and transmitting the modified main stream and the complementary information separately from a server to addressed equipment.

The present invention relates to a method of coding and / or decoding groups of pictures. According to the invention, during the temporal decomposition of a stream of pictures within the framework of 3D wavelet processing, the number of pictures, the choice of the reference picture and the direction of temporal decomposition for each picture sequence of GOP type are adapted in order to minimize the number of unconnected pixels.

The invention discloses a distribution network failure moment determining method based on multi-order wavelet function transformation. The method is capable of adapting to multiple failure types and multiple failure locations and accurately positioning the failure moment. The method disclosed by the invention comprises the following steps: adopting FFT (Fast Fourier Transform) of a moving time window according to a general format (COMTRADE) waveform file exchanged by transient data of a power system collected by a failure indicator, judging aiming at the calculated distortion factor, and generally locating the failure moment, so as to save time for subsequent wavelet processing; and accurately locating failure points by adopting a method for performing wavelet transform by adopting a multi-order wavelet function. According to the method, characteristics of wavelet functions of different orders are utilized, the stability and accuracy of failure moment determination are taken into account, the effectiveness of the method is validated by analyzing various different actual failure waveforms, and reliable method supports are provided for detection of the failure indicator device.

The invention discloses a wavelet analysis post-processing method and device for a power transient signal. The method is to conduct the following one or more post-processing on the wavelet coefficients after the power transient signal is analyzed by wavelet, and the result is to send power Monitoring center processing: modulus maximum extraction, singularity detection, obtaining modulus maximum points and singularity; statistical processing or cluster analysis of wavelet coefficients; neural network classification, that is, wavelet coefficients or wavelet post-processed data as neural Network input, output neural network classification results; energy analysis, to obtain energy distribution coefficient and energy fluctuation coefficient; wavelet entropy calculation, to obtain wavelet energy spectrum entropy or wavelet time entropy or wavelet singular entropy or wavelet time-frequency entropy or wavelet average entropy or wavelet distance entropy. It can effectively extract the characteristics of power transient signals, which can be applied to power system transmission line traveling wave distance measurement and fault identification, power quality analysis and equipment fault diagnosis.