41results about How to "Increased signal energy" patented technology

The invention relates to a wide band impulse signal detect radar induction reform. It comprises transmitting aerial, receiving aerial, wherein medium plate which is inductivity graded multilayer is posited on the top of soil area, the layered medium which formed wide band impulse signal detect radar is loading induction reform.

The invention discloses a torsional mode magnetostriction sensor array, and belongs to the field of ultrasonic non-destructive testing. According to the phenomenon that an SH wave vibration mode in a plate is similar to a torsional mode in a pipeline, an MPSA (modified planar solenoid array) coil suitable for pipeline configuration and array is provided, and the torsional mode magnetostriction sensor array is designed and researched to excite the torsional mode in a pipeline. Tests verify that a T (0, 1) mode can be excited on a pipeline by the researched torsional mode magnetostriction sensor array, and in the tests, the frequency response characteristic of the sensor array is tested. The sensor array is used for rapidly and effectively detecting the position of a defect in an alloy steel pipe, the positioning precision is relatively high, and a basis is established for implementing two-dimensional defect imaging in the pipeline by the sensor array combined with a phased array principle.

The invention relates to a multi-path slow frequency hopping signal anti-interference processing system which comprises a shunt demodulation unit, a unique code capturing unit, a power deciding unit, a data processing unit and a decoding unit. According to the characteristics of the slow frequency hopping system, the system captures all service hops, judges the power magnitudes of the service hops, detects whether interference exists in received signals or not according to the capture result and the power judging result of each hop, sets data of the service hops with interference to be zero, and decodes phase-adjusted base band demodulation signals through the LDPC decoding method so that it can be ensured that decoding can still be correctly conducted under the condition that interference exists and the anti-interference capacity of the system can be improved; the system accumulates correlation values of multiple service hops within a time slot in the service hop related capturing process and calculates phase errors of the time slot according to the accumulated correlation values, and therefore the time slot phase capturing probability is greatly increased.

The present invention provides a double-layer sector array folded coil structure integrated in a flexible circuit board, and designs and develops an arrayed omnidirectional type horizontal shear modal magnetostrictive transducer. Based on the magnetostrictive effect of ferromagnetic material nickel, the transducer realizes excitation of omnidirectional horizontal shear modal SH wave in the plate structure. Test verifies that the developed arrayed omnidirectional type horizontal shear modal magnetostrictive transducer can excite single SH0 modal waveguide inaluminum plate, and verifies that the developed omnidirectional type horizontal shear modal magnetostrictive transducer has better frequency response characteristics. The developed omnidirectional type horizontal shear modal magnetostrictive transducer and an array combined imaging algorithm can achieve efficient defect imaging on plate structure in wide range and board structure, and has very great value and potential in health monitoring and non-destructive evaluation of the plate structure.

A method and apparatus for detecting previous packet loss in non-packetized speech by applying one or more filters to a segment of said non-packetized speech, each of said one or more filters determining an energy parameter value for a given frequency band of said segment of said non-packetized speech; comparing one or more of said determined energy parameter values to one or more corresponding thresholds; and detecting previous packet loss based on said comparison of said one or more of said determined energy parameter values to said one or more of said corresponding thresholds.

The invention discloses a multi-antenna OFDMA signal decoding method based on rapid and independent component analysis. The method comprises the following steps: step 1, establishing a signal model for meeting the requirement of a rapid and independent component analysis algorithm on an input signal; step 2, conducting PCA whitening on an observation vector under Gaussian noise; step 3, separating a plurality of user information modulated on OFDMA subcarriers without knowing any information about the subcarriers; and step 4, performing subcarrier sequence estimation and OFDMA user identification. According to the method, mathematical statistical modeling is conducted on multi-antenna OFDMA signals based on Fast-ICA, and blind channel estimation and decoding are also performed, so that the signal energy is increased without removing a cyclic prefix, and the decoding performance is improved. Through adoption of the method, timing is not needed at a receiving end, blind separation and decoding are conducted on the OFDMA signals, and the decoding performance is good.

The invention discloses a multichannel laser induced breakdown spectrometer and a multichannel spectral detection method. The spectrometer comprises a circular ring flange and a laser, wherein a plurality of detection lens groups are uniformly mounted on the circular ring flange; the laser is arranged at the center of the circular ring flange; the transmitting end of the laser and the light incidence end of each of the detection lens groups face to a detected object; connecting optical fibers are arranged at the light emergence end of the of each of the detection lens groups, the tail ends ofthe connecting optical fibers are combined into an optical fiber bundle, and the optical fiber bundle is connected with a spectral detector; after the laser emits laser light, a plasma substance is induced from the detected object, and light radiated during the energy level transition is received by the plurality of detection lens groups on the circular ring flange and transmitted to a spectrum detector by the connecting optical fibers and the optical fiber bundle. The multichannel laser induced breakdown spectrometer and the multichannel spectral detection method disclosed by the invention not only can solve the selection problem of a receiving angle, but also can enhance the signal energy finally entering the spectrum detector through a multichannel mode, thereby improving the signal-to-noise ratio.

The invention provides a multi-beam switching cylindrical array antenna structure and a radar system. The multi-beam switching cylindrical array antenna structure comprises a transmitting module and a receiving module which are oppositely arranged in the pitching direction, wherein a metal gap is formed between the transmitting module and the receiving module; the transmitting module comprises a plurality of transmitting array elements which are circumferentially distributed in the azimuth direction, and the receiving module comprises a plurality of receiving array elements which are circumferentially distributed in the azimuth direction; the transmitting array elements and the receiving array elements are the same in number and are arranged in the pitching direction in a one-to-one correspondence mode. On the basis of the multi-beam switching cylindrical array antenna structure, arbitrary switching and combination of various beams can be realized at the transmitting module part by controlling the phase of each channel, full coverage of 360-degree space is realized, a specific transmitting waveform is formed, and the detection distance is increased under the condition of limited transmitting power; in the receiving module part, signals are independently received through the plurality of receiving array elements so that the signal energy in a main wave beam range can be increased.

The invention provides a message demodulation method and device, and the method comprises the steps: obtaining a differential phase value corresponding to the phase value of a to-be-demodulated message and a corresponding maximum likelihood ratio, and storing the differential phase value and the maximum likelihood ratio in a buffer Buffer; obtaining a first message of the first M bits in the buffer Buffer; and when the first message does not pass the preset verification, accumulating the M-bit message after a preset time interval with the first message to obtain a second message, and outputting the message words of the second message. With application of the scheme, the tracking output signal energy is increased through accumulation and the signal-to-noise ratio is increased; besides, thereliability of accumulated message judgment is improved through a probability statistics method of the maximum likelihood ratio, the sensitivity of message decoding is further improved and the problemof inaccurate positioning caused by errors due to frequent message demodulation in related technologies is solved.