6 results about "Polyphase filter bank" patented technology

This application relates to the field of radar signal processing technology, and in particular to a radar interference identification method based on multi-domain feature association and fingerprint tracing. The method includes: digitally channelizing the received radar signal using a polyphase filter bank, decomposing it into multiple narrowband sub-channels, and selecting effective sub-channels; extracting macroscopic features from the outputs of the effective sub-channels to construct high-dimensional feature vectors; inputting the high-dimensional feature vectors into a pre-trained random forest classification model for initial interference pattern judgment to obtain preliminary judgment results; if the preliminary judgment result is deceptive interference and the signal-to-noise ratio of the effective sub-channels is higher than a preset fingerprint extraction threshold, then extracting microscopic features from the outputs of the effective sub-channels to construct microscopic fingerprint vectors; performing fine analysis of the pulse leading edge fingerprint based on the microscopic fingerprint vectors to obtain secondary fingerprint analysis results; and combining the preliminary judgment results and the secondary fingerprint analysis results to obtain the final identification result used to characterize the interference pattern and the identity of the interference source.

The application discloses a target channel selection output method and system for frequency division multiplexing superconducting detectors, and belongs to the technical field of digital signal processing and superconducting detector readout electronics. The method aims at the problems of high resolution channelization resource occupation, high full spectrum output bandwidth pressure, and obvious spectrum leakage and crosstalk under high multiplexing ratio. On the basis of high resolution channelization processing, the mapping relationship between target frequency points and channels and the target channel selection output mechanism are introduced. After the wideband digital input signal is processed by the polyphase filter bank channelization, only the complex data corresponding to the target frequency points containing effective signals are selected and output, and are further separated into I / Q data stream output. The scheme combines high resolution channelization processing with the mapping driven selection output mechanism, reduces resource occupation and data transmission bandwidth while ensuring frequency resolution, and improves real-time performance and signal fidelity in the readout scene of high multiplexing ratio detectors.

The application relates to the field of wireless communication anti-interference technology and discloses a wideband spectrum interference sensing and intelligent parameter estimation method and system.The method comprises the following steps: extracting a training sequence part from a mixed receiving signal, performing channel estimation to obtain a channel response estimation value, and utilizing the channel response estimation value to cancel the mixed receiving signal to obtain a mixed signal of interference and noise; dividing the mixed signal of interference and noise into multiple uniform subchannels through a polyphase filter bank with frequency overlap; performing spectrum sensing on each subchannel through a fast covariance matrix eigenvalue (FCME) algorithm, and identifying and splicing the same interference across adjacent subchannels through a multi-subband joint detection algorithm; extracting a time-frequency diagram and IQ data according to the interference detection result, and pre-processing the time-frequency diagram; and inputting the time-frequency diagram into a YOLOv7 deep neural network to output parameter information of each interference through a target detection method, so that accurate intelligent estimation is realized through the above method.

The application discloses a signal processing method and system of an S-band narrowband digital processor of a phased array, and the method comprises the following steps: receiving and pre-processing service signals from a comprehensive processor, and converting the service signals into zero intermediate frequency signals; channelizing and decomposing the signals into a plurality of sub-channels with different center frequencies and bandwidths through a multi-phase filter group; performing deep-level feature extraction on the signals of the sub-channels by using a deep belief network which is stacked by a plurality of restricted Boltzmann machines; searching for optimal beam forming weights in a feature space by using a particle swarm optimization algorithm; finally, performing beam synthesis by weighting and summing the signals of the sub-channels according to the obtained optimal weights, and converting the result back into an analog intermediate frequency signal for subsequent transmission processing. The application can improve the processing performance and the accuracy of beam forming of a phased array system in S-band narrowband digital processing.

The application provides a digital channelization implementation method based on a fractional multiple oversampling polyphase filter bank, which works in a parallel pipeline mode, the input parallel channel number is A in , the output parallel channel number is A, the channel number is M, the length of each phase sub-filter is L, the total filter length is L*M, wherein M=M1*A, A in <A, M1, A in , A, L are all positive integers. The method comprises the following steps: shaping A in parallel input data into A parallel data through a data shaping module; rearranging the input data according to M phases through an input data rearrangement module, and outputting A*L data under each clock; calling filter coefficients according to the parallel degree A through a sub-filter and a scheduling module to perform filtering; performing channel frequency shift through a parallel hierarchical FFT module; and finally correcting the phase deflection caused by oversampling through a phase rotation module to obtain the channelized result. The application realizes real-time digital channelization with large bandwidth and multiple channels based on a polyphase filter bank in limited resources, and solves the problem of traditional polyphase filter channel spectrum attenuation with flexible channel division.

A communications waveform schema integrates security at the physical layer and has many desirable features of traditional LPI / LPD waveforms. To provide additional covert aspects in communications a single-carrier base waveform is divided up in frequency and / or time and redistributed pseudo-randomly among subcarriers and channel assignment. Multiple matched polyphase filterbank channelizers are used so that each individual channel has a bandwidth well below a Nyquist rate for information carried by the base waveform, thereby making full data extraction from any individual channels a theoretic impossibility. The individual channels do not carry enough information from the base waveform to be useful and only in the aggregate can the entire base waveform be reconstructed. Individual channels are up-converted onto pseudo-randomly chosen carrier frequencies within the bandwidth of the high rate hardware IF in such a way as to obfuscate the order in which they occur in the base waveform.