4 results about "Blind equalization" patented technology

The application provides a multimode blind equalization method based on a swallow line function and a variable fractional order gradient. The algorithm uses statistical characteristics of an equalizer output signal and a transmitting end signal to construct a multimode cost function based on a swallow line function, so that phase errors in a channel equalization process can be compensated without an additional carrier recovery loop. Subsequently, a variable fractional order gradient method is used to replace a traditional fixed order gradient updating mode to adaptively update equalizer weight vectors, so that optimal weight vectors are obtained. Compared with the prior art, the application can not only realize channel equalization and phase recovery, but also effectively reduce residual inter-symbol interference and bit error rate in a strong impulse noise environment, while the convergence speed is accelerated, and higher equalization efficiency and robustness are shown.

This invention relates to the field of telemetry technology, proposing a telemetry system and method suitable for close-range testing of high-speed rotating components. The telemetry system includes a rotating transmitter and a fixed receiver. The rotating transmitter includes a target rotating component, a signal acquisition and processing module, and a transmitting antenna. The signal acquisition and processing module acquires and processes test parameters of the target rotating component and radiates the processed test data outward through the transmitting antenna. The fixed receiver includes a receiving antenna, a signal optimization module, and a data processing module. The receiving antenna receives the test data, the signal optimization module performs adaptive diversity synthesis and blind equalization processing on the test data to obtain processed data, and the data processing module outputs corresponding telemetry data based on the processed data. This invention enables high bit rate and low bit error rate transmission, meeting the high-precision, high-speed rotation testing requirements of aerospace, industrial equipment, and other fields.

This invention discloses an adaptive blind demodulation method, system, terminal, and medium based on a satellite communication system. The method includes: performing parameter estimation, frequency offset compensation, and timing synchronization processing on the original baseband sampled data sequence to obtain a single symbol rate data symbol sequence; performing hierarchical phase-locked loop carrier coarse synchronization iterative processing on the single symbol rate data symbol sequence to obtain a target convergent constellation diagram symbol sequence; extracting high-order cumulant features based on the target convergent constellation diagram symbol sequence and performing modulation scheme identification and confidence judgment, iterating until a preset judgment condition is met to obtain a target modulation identification result; and performing adaptive carrier fine phase-locking and blind equalization joint processing on the target modulation scheme to obtain a demodulated symbol sequence. This invention solves the coupling problem between carrier synchronization and modulation identification by combining hierarchical carrier synchronization, high-order cumulant feature identification, and adaptive fine phase-locking blind equalization, thereby improving demodulation reliability.

The application discloses a variable step-size dual-mode blind equalization method for QAM signals, a storage medium and equipment, and belongs to the technical field of blind receiving and demodulation of wireless communication systems. The application solves the problem that the traditional hard switching mechanism is easy to cause system transient oscillation and lock loss. The application adjusts the iteration step size by constructing an error exponential function with a transient error signal as an independent variable, automatically gives the system a larger step size in the initial stage of the algorithm to accelerate convergence, and adaptively attenuates when the error tends to zero to suppress steady-state fluctuations, effectively overcoming the inherent contradiction between convergence speed and steady-state accuracy of the traditional fixed step-size algorithm; a soft switching mechanism based on a continuous confidence factor is used to replace the traditional hard switching decision, the global convergence ability of the MMA algorithm and the extremely high steady-state accuracy of the DD algorithm are smoothly and non-oscillatingly fused through a nonlinear fusion factor, transient oscillation and error propagation effect caused by mode switching are significantly suppressed, and system lock loss is avoided. The application can be applied to blind equalization of wireless communication systems.