33results about How to "Method algorithm is simple" patented technology

The invention relates to a three-level active electric filter compensation current calculation method based on non-harmonic detection control. An IGBT start pulse signal, a DC side capacitor voltage and a power source voltage are utilized to calculate an inductor voltage, and a compensation current outputted by a three-level active electric filter is further acquired. A cascade signal delay cancellation (CDSC) module is utilized in a calculation process to acquire a compensation current error signal, and calculation accuracy is improved. The whole calculation process is simple and reliable, advantages of non-harmonic detection control are integrated, and the method is suitable for all NPC type and T type topological three-level active electric filters based on non-harmonic detection control.

The present invention discloses a method for watermarking robust audios with invariable time scale based on zero-crossing rates, which comprises the following steps: firstly, dividing an original audio signal A into a plurality of nonoverlapping audio frames; secondly, calculating the zero-crossing rate of each audio frame, and selecting M1 audio frames with larger zero-crossing rates for embedding watermarks according to a preset threshold value T; thirdly, dividing each one of the M1 audio frames into a plurality of nonoverlapping audio segments of which the number is accordant with the total bit number of the watermarks to be embedded, quantizing the average value of nonoverlapping audio segment samples so as to embed watermark bits, and modifying sample values which correspond to each audio segment of the watermarks to be embedded, quantizing the average value of nonoverlapping audio segment samples so as to embed watermark bits; and finally, interconnecting the audio segments containing the watermarks to obtain audio frames containing the watermarks so as to form the final audios with the watermarks. The method has a simple algorithm, is applicable to all types of audio signals, and not only can effectively resist attacks of conventional signal processing, but also has strong robustness for time scale modifications in a resampling form., but also has strong robustness for time scale modifications in a resampling form.

The invention provides a Capon beamforming-based positioning method and device. According to the Capon beamforming-based positioning method and device, K receiving antennas are set to form a signal receiving array, and M signal transmitting points are set; a covariance matrix Rxx is calculated by using a signal matrix outputted by the signal receiving array; the constraint optimization problem of the linearly constraint minimum variance criterion is solved, so that a spectral function can be constructed; M maximum spectral peaks are searched; and a direction of arrival is calculated. According to the method, beacon points deployed in a monitoring area are adopted to be networked with a wireless gateway so as to communicate with the wireless gateway; data are transmitted to a cloud end through a wireless communication module; cooperative sensing is performed, and the information of signal transmitting points in a network coverage area is acquired and positioned; the monitoring data of the cloud end are matched with a map and the like, so that intelligent parking can be realized. With the method adopted, the number of vehicles does not need to be known in advance or estimated, and therefore sampling data length can be decreased; desired signals are enhanced, interference is suppressed, and therefore, the signal to interference plus noise ratio of the output of a system can be improved; and a robust Capon algorithm is modified to improve the deviation of a direction vector from an actual environment, and therefore, positioning performance can be improved.