36 results about "Channel complex" patented technology

A method of extracting data from a received signal including multi-path interference in a rake receiver. The method includes sampling and filtering the received signal; estimating a time delay τl between paths for the filtered samples ψ(τ); and estimating channel complex coefficient cl for the filtered samples ψ(τ). Transmitted data x(τl) is extracted from the filtered samples ψ(τ) for each path l by solutions of simultaneous equations of the following filtered samples ψ(τ) equationψ⁡(τ)⁢Rff-1⁡(τk-τ^0)⁢ΛssH⁡(τ^k)=∑l=0Np+1⁢⁢ci⁡(τl)×(τl)⁢Λss⁡(τl)⁢Rff⁡(τl-τ^0)⁢Rff-1⁡(τk-τ^0)⁢ΛssH⁡(τ^k)+⁢(τ)wherein k is a particular path, Np is the number of visible paths, Rƒƒ(τl–τo) is a double convolution matrix of the filtering process and Rƒƒ−1(τk−–o) is the pseudo inverse, Λss(τl) is the product of spreading and scrambling matrices and ΛssH(τk) is the inverse, and (τ) is noise.

Embodiments of the invention provide a narrowband internet of thing (NB-IoT) physical downlink channel complex transmission method, and a corresponding base station and user equipment performing the method. According to the embodiments of the invention, the base station comprises a mapping unit and a transmitting unit, wherein the mapping unit is used for multiplexing more than one NB-IoT physical downlink channel in a same sub frame, the NB-IoT physical downlink channel comprises an NB-IoT physical downlink control channel (NB-PDCCH) and / or an NB-IoT physical downlink shared channel (NB-PDSCH), the maximum particle size of resource allocation of the NB-IoT physical downlink channel takes an enhanced resource element group (EREG) as a unit, the EREG consists of time-frequency two-dimensional limited multiple resource elements in the same sub frame, and the rransmitting unit is used for transmitting downlink sub frames.

The invention provides a phased array radar angle measurement system based on positive and negative frequency modulation slope linear frequency modulation, wherein, the radar reflection echo signals are sequentially received according to the time sequence of the signals transmitted by the pulse radar system; the echo signal weighting coefficient generation module calculates and obtains an echo signal weighting coefficient of each subarray or array element of the phased array antenna according to the guide angle of the phased array antenna; the sum-difference channel echo generation module obtains a sum-difference channel echo by using each subarray or array element echo signal and a corresponding weighting coefficient; the echo signal processing module performs pulse compression on the sum-difference channel echo and detects a sum-difference channel complex signal at the distance of the target; the angular error calculation module calculates an angular error value corresponding to thepositive and negative frequency modulation slopes according to the amplitude comparison single pulse angle measurement method; and the target angle calculation module calculates the angle of the target.

The invention discloses a binaural speech enhancement method based on deep learning, comprising the following steps: respectively processing a left / right channel noisy speech signal containing a target speech signal to be enhanced so as to obtain a left / right frequency domain signal, and combining amplitudes thereof to obtain single-channel complex features; using the frequency domain signal of the left / right channel and corresponding target frequency domain signal theoretical value to calculate corresponding target speech ideal complex masking respectively; combining to form a target speech single-channel complex masking theoretical value, combining the single-channel complex features to train a complex feedforward neural network so as to obtain a binaural speech enhancement model; usingthe target speech single-channel complex masking estimated value outputted by the model to respectively process the left / right channel noisy speech signal so as to obtain a left / right channel frequency domain signal; and finally obtaining a corresponding target speech time-domain signal. By the method, noise interference can be suppressed and spatial information of a target sound source can be maintained. By making full use of the generalization ability of deep neural networks, the enhancement of binaural speech is achieved.

The invention discloses a channel estimation method based on a complex exponential-basis expansion model. The method comprises the following steps of: (1) estimating gradient of channel impulse response in intervals according to the data processed by a wireless receiver; (2) based on the CE-BEM (Complex Exponential-Basis Expansion Model), calculating baseline compensation quantity of an observed value, and a new signal model; (3) estimating the channel impulse response after compensation; and (4) calculating the channel impulse response before compensation. The invention further discloses a channel estimator. With the method and the estimator provided by the invention, the error of the CE-BEM is reduced, the accuracy of channel estimation is improved, and the implementation complexity is low.

The present invention proposes a phased array radar angle measurement system based on positive and negative frequency modulation slope linear frequency modulation, wherein, the radar reflection echo signals are received sequentially according to the time sequence of the pulse radar system transmission signals; the echo signal weighting coefficients are generated The module calculates the weighting coefficients of the echo signals of each subarray or array element of the phased array antenna according to the steering angle of the phased array antenna; the sum and difference channel echo generation module uses each subarray or array element echo signal and the corresponding weighted coefficient coefficient to obtain the sum and difference channel echo; the echo signal processing module performs pulse compression on the sum and difference channel echo and detects the complex signal of the sum and difference channel at the distance of the target; the angle error calculation module measures the angle according to the ratio amplitude single pulse The method calculates and obtains the angular error value corresponding to the positive and negative frequency modulation slope; the target angle calculation module calculates the target angle.

A WCDMA receiver in which the dependencies of different functional modules are arranged to allow proper tailoring of the Channel Estimation (CE) module bandwidth. A PreCE provides rough estimation results of the channel complex gain. The rough estimation results are passed to the Automatic Frequency Control (AFC). The AFC outputs a signal transmitted to two mixers. The first mixer mixes the output of the PreCe with the output of the AFC and outputs the result to a Velocity estimator (VE) and a PostCE to generate the compensating signals. The output of the VE is also transmitted to the PostCE. The output of the PostCE is sent to a Maximum Ratio Combining module, whose output is mixed by the second mixer with the output of the AFC to generate a final signal.

The invention provides a method for discovering dirty data propagation paths based on complex networks, which can translate binary programs without source codes, process the obtained results, and mine and generate useful information. Step 1: Decompile the binary file and get the intermediate code of C language. After testing a simple C language program, get the intermediate language code; Step 2: Capture the function call path and resolve the function address into a function Name, process and simplify, and generate a matrix format; finally generate a function call relationship graph; the third step: analyze the function call relationship graph, obtain node, edge, weight information, calculate node degree, and establish a complex network with key nodes Figure; the fourth step: According to the non-uniform characteristics of the power law distribution of the complex network graph, find out the points related to the construction of dirty data and the points with high calling frequency.

The invention discloses a preparation method of a magnetic carbonaceous solid acid catalyst. The method uses waste banana peels as raw materials. First, the banana peel fragments are soaked in a certain concentration of ferric chloride aqueous solution, and after the coordination modification of metal iron ions The iron-based composites that can form porous channels, and then use this composite as a carrier to construct magnetic porous carbon materials, and use the hydrothermal sulfonation method to functionalize the surface of magnetic porous carbon, and finally prepare magnetic carbonaceous solid acid catalyst. The method of the invention is simple and the conditions are mild, and the specific surface area of ​​the obtained magnetic carbonaceous solid acid catalyst is 160-1100m 2 / g, the pore volume is 0.17~0.74cm 3 / g, the average mesopore size is 6.1-11.4nm, and the highest acidity is 2.68mmol H + / g, and has high water resistance, stability, repeatability, and good external magnetic field separation ability, and exhibits extraordinary catalytic activity in the reaction of esterified oleic acid and methanol, and is expected to be used as a high-efficiency catalyst for Preparation of biodiesel by esterification.

The invention provides a modeling generation method for a non-stable fading channel. The method is suitable for non-stable fading channel modeling and simulation generation in a mobile propagation scene, can be used for accurately reproducing a statistical characteristic of the non-stable fading channel, and can be applied to the field of testing and verification of mobile communication system performance in a time varying scene. According to the method, a channel state is supposed to change continuously and slowly, approximately considered to keep constant within a certain time interval, and modeled as a sum of channel complex gains of a line-of-sight part and a non-line-of-sight part. Channel non-line-of-sight fading of each cluster is obtained by overlapping of a plurality of paths of complex exponential functions, and discrete Doppler frequency parameters of different paths of complex exponentials change linearly in a serrate form. Moreover, a frequency parameter real-time updating calculation method is provided, so that value continuity and the continuity of an output channel fading phase are ensured.

The present invention provides a scrambling code cancellation method aimed at combining channel codes and scrambling codes, comprising the following steps: performing frame division processing on demodulated data; counting the number of frames under each frame length; Two frames are extracted from the set with the number of frames greater than 1, and the bearer data of the two frames are extracted and put into the sequence S1 and the sequence S2 respectively; XOR the sequence S1 and the sequence S2 to obtain the sequence with the scrambling code removed; based on removing The sequence of the scrambling code is identified by the channel code identification method. The invention utilizes the properties of the same frame scrambling position and the same scrambling sequence to cancel the scrambling code, and proposes a scrambling code canceling method in which the channel code and the scrambling code are combined. Then, according to the property that the codewords obtained by XOR between codewords of the channel codes still belong to the codewords in the original codeword space, the existing channel code recognition method can be used to identify the channel code parameters.

The embodiment of the invention discloses a method and a device for channelizing a real signal. The method comprises: after receiving a certain multichannel real signal, carrying out shunt delay on the multichannel real signal to obtain 2D channel data; respectively carrying out 2D fold extraction on the 2D channel data, and alternately changing the symbol of each extracted channel data; filtering the 2D channel data processed by symbol change; synthesizing the filtered 2D channel data into D channel complex signal, and carrying out multi-index modulation on each channel complex signal; and carrying out D point FFT on the modulated each channel complex signal, and outputting a D channel baseband signal. The invention carries out extraction treatment 2 folds higher than the prior art on a multiphase treatment front end, thus reducing the complexity of post signal treatment; and the invention carries out optimization on the multi-index modulation part, thus lowering the complexity of the channelized structure of the existing filter set and solving the problem of over high consumption of system resource.

The invention provides a downlink synchronous calibration method and device in a TD-SCDMA system. The method comprises the steps of: receiving a downlink signal; searching for a downlink synchronization code (SYNC_DL) in the received downlink signal to control synchronization timing; using the midamble code of the received signal to calculate a channel impulse response to adjust the synchronization timing; Obtain the channel impulse response or channel complex correlation corresponding to the DwPTS channel; search for the third predetermined path with the strongest energy as the candidate position of the left boundary of the energy window; obtain the energy in the third predetermined path with the strongest energy greater than the specified The path of the predetermined threshold is a survival path, wherein the predetermined threshold is a function of the largest path among the third predetermined number of paths with the strongest energy; obtaining the position of the leftmost path in the survival path is the window Left boundary to obtain an adjustment amount for synchronization timing calibration; further adjust and / or calibrate the synchronization timing. The device includes: a receiving device; a searching device; a control computing device; an adjusting device. By using the invention, the performance of the system is effectively improved.

The invention belongs to the technical field of wireless communication, and particularly relates to a channel estimation method and system based on a multi-dimensional Hankel matrix in a large-scale MIMO system. The method comprises the following steps: S1, a receiving end receives a signal sent by a base station, and obtains preliminary estimation channel information according to the received signal; s2, constructing a plurality of Hankel matrixes according to the preliminarily estimated channel information; s3, sequentially performing singular value decomposition on the plurality of Hankel matrixes to obtain a plurality of groups of azimuth arrival angle estimation values and channel complex gain coefficient estimation values; s4, selecting a group of azimuth arrival angle estimation values and channel complex gain coefficient estimation values with the highest channel utilization rate; and S5, recovering channel state information based on the selected azimuth arrival angle estimated value and the channel complex gain coefficient estimated value. Compared with a traditional channel estimation method, the channel estimation method based on the multi-dimensional Hankel matrix in the large-scale MIMO system has the advantages that the higher channel utilization rate can be achieved, and therefore the communication performance of the MIMO system is more reliable.

The invention discloses a speech enhancement method, device and electronic equipment based on spatial features. The method includes: performing Fourier transform on a dual-channel noisy speech to obtain a dual-channel complex spectrum; obtaining the first dual-channel complex spectrum based on beamforming A single-channel complex spectrum and a second single-channel complex spectrum; calculating the logarithmic power spectrum of the first single-channel complex spectrum; calculating a direction energy ratio based on the energy of the first single-channel complex spectrum and the energy of the second single-channel complex spectrum, and Take the logarithm to obtain the energy ratio in the logarithmic direction; use the logarithmic power spectrum and the energy ratio in the logarithmic direction as feature inputs to the pre-trained speech enhancement neural network to obtain the masking value; add the masking value to the first single-channel complex spectrum, and The first single-channel complex spectrum after the masking process is inversely Fourier-transformed to obtain the enhanced speech. The solution provided by the embodiment of the present invention can effectively reduce noise and better avoid voice distortion.

The invention discloses a synthetic aperture radiometer based on a single radio frequency receiving array, which relates to a microwave imaging system. It consists of an antenna array, a broadband single radio frequency receiving processing module, a digital multi-channel complex correlation processing module and an imaging inversion processing module. It uses a single radio frequency receiving array technology to achieve the effect of multiple parallel radio frequency channels equivalently with one broadband radio frequency channel, which can not only effectively reduce the radio frequency complexity, but also achieve better channel consistency.