7 results about "Doppler tolerance" patented technology

The invention provides a multifunctional integrated waveform design method based on a multi-sub-pulse structure, and belongs to the field of radar detection communication anti-interference integration. Specifically, an information transmission modulation method based on joint modulation of partial phase modulation in sub-pulses and waveform position arrangement modulation between sub-pulses is proposed, and the communication rate is remarkably improved; intermittent sampling forwarding interference is effectively suppressed by using the orthogonal characteristic of waveforms between sub-pulses. A signal processing method based on monopulse multifunctional integrated echoes is provided, and Doppler tolerance is enhanced; according to the invention, the integration of detection, communication and anti-interference functions is realized, the detection and communication requirements of a high-speed moving target are met, and the engineering application value is high.

This invention discloses a signal Doppler tolerance and sidelobe optimization method based on a weighted ambiguity function template. The method includes determining a discrete ambiguity function based on a two-dimensional ambiguity function of a continuous signal and a radar transmitted signal; obtaining matched filtering results for signals with different Doppler frequency shifts and determining the main lobe and sidelobe positions based on the Doppler frequency shift results; for the Doppler frequency shift case, establishing a cost function for Doppler tolerance optimization and a weighted cost function for joint optimization of Doppler tolerance and sidelobe based on the main lobe and sidelobe positions, respectively; setting the weight coefficients of the weighted cost function according to signal characteristic requirements to obtain the target cost function; and using simulation parameters for iterative updating to obtain the optimization result. This invention can improve signal Doppler tolerance while reducing signal sidelobes, significantly improving the practicality of random noise signals; and it allows for setting weight coefficients according to signal characteristic requirements to adjust the optimization ratio of signal Doppler tolerance and sidelobe, providing strong flexibility.

The application provides an m sequence optimization method for a satellite-ground integrated sensing system test, comprising the following steps: step 1, reference sequence performance evaluation: the reference performance comprises a reference peak-to-average power ratio, a reference peak-to-side lobe ratio, a reference integrated side lobe ratio and a reference Doppler tolerance; step 2, comprehensive multi-dimensional cost function construction and mixed optimization strategy: step 201, constructing a comprehensive multi-dimensional cost function capable of weighted adjustment: step 202, defining a normalization function based on the reference performance: step 203, configuring the performance on demand based on the weight coefficient: step 204, minimizing the cost function by using a mixed optimization algorithm; and step 3, generating a final integrated sensing test sequence. The application realizes the collaborative optimization of multiple key performances of communication and sensing for the first time, and can generate a special sequence with excellent comprehensive performance, which can meet the stringent integrated satellite-ground sensing system test requirements.

The application discloses an OFDM-LFM integrated signal waveform receiving method and equipment based on fractional Fourier transform, which combines and improves LFM and OFDM, adopts OFDM-LFM integrated radar communication signals taking orthogonal LFM signals as subcarriers, and has the advantages that, due to the large Doppler tolerance of the LFM subcarriers, compared with sinusoidal subcarriers, the method can not only improve radar range resolution and spectral efficiency, but also has strong ability to avoid Doppler effect, and can reliably transmit information; when receiving OFDM-LFM signals, in order to solve subcarrier frequency linear transformation and radar parameter extraction and other problems, based on the sensitivity of a fractional Fourier transform (FRFT) to LFM signals, the application uses the FRFT as an integrated signal receiver, realizes separation of an integrated signal communication receiver and a radar receiver, reduces the complexity of the system, and improves the system performance.

The application belongs to the technical field of synchronous signal capture, and discloses a kind of underwater acoustic PN signal time domain coarse capture method and system based on deep learning, adopt receiving end local carrier compression algorithm to convert PN correlation gain amplitude frequency deviation response into the approximate flat of multiple SINC function module non-coherent accumulation, based on the circular convolution of local carrier compression time domain parallel correlation result output is used for TCN-Seq2Seq model provides the correlation waveform feature of large doppler tolerance;Utilize TCN-Seq2Seq model to realize the time domain synchronization of low signal-to-noise ratio condition based on the circular correlation output waveform of carrier compression, identify and analyze the received waveform, output waveform time domain range, obtain the coarse estimation of Doppler frequency deviation, complete time domain frequency domain coarse capture.The application greatly reduces the computing overhead, and has high value for the application of underwater acoustic communication of PN signal in military and biological friendly direction.

The invention relates to an adaptive pulse compression method of a convolutional neural network. The method comprises the following steps: constructing a pulse compression network consisting of a plurality of cascaded sub-networks; wherein each sub-network comprises a Doppler compensation branch and a power estimation branch which are arranged in parallel, feature fusion is realized through cross-level residual connection, and output ends of the Doppler compensation branch and the power estimation branch are respectively connected with a CNN-based pulse compression branch; doppler tolerance and array element error compensation priori knowledge are embedded into network weight through offline training, so that the network has robustness for unmodeled distortion; and receiving a radar transmitting signal and a radar echo signal, performing end-to-end forward propagation by using the pulse compression network, and synchronously outputting an adaptive pulse compression result after sidelobe suppression and Doppler offset compensation. Compared with the prior art, the comprehensive performance bottlenecks of the existing adaptive pulse compression method in the aspects of calculation complexity, Doppler compensation robustness, complex scene adaptability and non-ideal factor fault tolerance are overcome.

The invention provides an m sequence optimization method for satellite-to-ground sensing integrated system testing. The m sequence optimization method comprises the steps that 1, reference sequence performance evaluation is carried out, wherein reference performance comprises a reference peak-to-average power ratio, a reference peak value sidelobe ratio, a reference integral sidelobe ratio and reference Doppler tolerance; step 2, constructing a comprehensive multi-dimensional cost function and a hybrid optimization strategy: step 201, constructing the comprehensive multi-dimensional cost function capable of performing weighted adjustment; step 202, defining a normalization function based on reference performance; step 203, performing performance on-demand configuration based on a weight coefficient; step 204, performing cost function minimization by adopting a hybrid optimization algorithm; and step 3, generating a final sensing integration test sequence. According to the method, collaborative optimization of multiple key performances of communication and perception is realized for the first time, and a special sequence which is excellent in comprehensive performance and can meet the test requirements of a strict satellite-ground communication and sensing integrated system can be generated.