4results about How to "Improve demodulation efficiency" patented technology

The invention relates to an interference type sensing device for multiplexing and a demodulation system and method, the sensing device is formed by sequentially connecting a plurality of interference type sensing units in series, and each interference type sensing unit is characterized in that two input ends of a circulator are respectively connected with an F-P cavity optical fiber sensor and a linear chirp fiber grating sensor, and an output end of the circulator is connected with a coupler; the reflection bandwidth of the fiber bragg grating of the linear chirped fiber bragg grating sensor just covers one period of the reflection spectrum of the F-P cavity, and the reflection wavelength ranges of the fiber bragg gratings of the plurality of interference type sensing units are not overlapped. The demodulation system comprises a broadband light source, an interference type sensing device and a signal detector. According to the invention, real-time measurement of a plurality of sensors on one optical fiber is realized, the multiplexing capacity is improved, the structure of a detection and demodulation system is simplified, the number of required optical fibers is reduced, and the complexity of the system is reduced.

The present specification relates to the technical field of fiber-optic gyroscopes, and discloses a reciprocal structure 3x3 fiber-optic gyroscope and a use method thereof, to solve the problems of poor anti-interference, complex calculation, and no consideration of the influence of temperature change on test results, poor environmental adaptability, and limited practicality of a typical non-reciprocal structure 3x3 fiber-optic gyroscope; three photoelectric detectors, a 2x2 coupler, a 3x3 coupler, a temperature sensor, and a signal processing module; the 2x2 coupler, the 3x3 coupler, the first photoelectric detector D1, the second photoelectric detector D2, and the third photoelectric detector D3 constitute a reciprocal structure 3x3 fiber-optic gyroscope optical path. The reciprocal structure 3x3 fiber-optic gyroscope extracts a reciprocal end output signal, uses the reciprocal end output signal as a reference quantity for differential demodulation, eliminates the influence of optical path loss variation and light source fluctuation on the gyroscope output signal, and greatly improves the anti-interference of the gyroscope system.

The present invention belongs to the field of airborne sensors, and relates to a temperature-pressure composite sensor and a correction and solution method. The temperature-pressure composite probe includes a pressure sensitive element and a temperature sensitive element. The temperature-pressure composite probe detects the temperature and pressure of the measured medium. The solution unit demodulates, temperature compensates, and performs nonlinear correction on the outputs of the pressure sensitive element and the temperature sensitive element, respectively, to obtain the pressure P and the temperature T, and converts the output in the form of CAN through the output unit. The temperature-pressure composite sensor integrates temperature and pressure signal detection, conversion, conditioning, correction and solution, achieving a higher degree of integration. The correction method of the temperature measurement part of the sensor can be extended to a wider temperature range, thereby improving the temperature measurement accuracy in a wide temperature range. The solution process of the temperature-pressure composite sensor does not require very dense temperature points and pressure points, thereby improving the efficiency of demodulation.

The application discloses a data demodulation method of a transponder, and mainly solves the problem of low demodulation efficiency caused by the need of establishing symbol synchronization and tracking for implementing the demodulation of phase modulation data based on Hilbert transform. The implementation scheme is as follows: dividing the radar signal received by the transponder into two paths, performing Hilbert transform on one path to generate quadrature signals, and performing delay alignment phase on the other path to generate in-phase signals; performing the operation of the sine-cosine double-angle formula and the half-frequency processing on the quadrature signals and the in-phase signals to obtain the sine wave and the cosine wave of the carrier phase; substituting the quadrature signals, the in-phase signals, the sine wave of the carrier phase and the cosine wave of the carrier phase into the cosine two-angle difference formula to perform the operation and eliminate the carrier phase to obtain the demodulation data. The application does not need symbol synchronization for implementing the demodulation of phase modulation data based on Hilbert transform, and the establishment of symbol synchronization and the tracking of symbol synchronization are avoided, thereby saving the circuit, improving the demodulation efficiency and being applicable to the data communication of the transponder.