97 results about "Rotation factor" patented technology

A single-path delay feedback pipelined fast Fourier transform processor comprising at least one set of triplet FFT stage means: a first FFT stage means comprising a radix-2 butterfly, a feedback memory, and a multiplication by unity; a second FFT stage means comprising a trivial coefficient pre-multiplication, a radix-2 butterfly, a feedback memory, and a multiplication by selectable unity or W_N^N/8; and a third FFT stage means comprising a trivial coefficient pre-multiplication, a butterfly, a feedback memory, and a complex twiddle coefficient multiplication with coefficients determined using a twiddle factor decomposition technique.

The invention discloses a rotation constellation diagram based coding and decoding method for a spatial multiplex multi-aerial system. According to the method, the rotation constellation diagram based coding and decoding method and the spatial multiplex multi-aerial system are combined, a transmission signal is subjected to serial and parallel conversion at a transmitting end and a mapped onto a modulation constellation diagram, all constellation points rotate by using origin points as circle centers at set angles and reversely rotate at the same set angles after signs are detected at a receiving end, a signal sequence is modulated through the constellation diagram and is subjected to parallel and serial conversion, and the signal is output. By the method, the problem of error rate increase caused by constellation point overlap in a related channel is solved, and the error rate of the spatial multiplex multi-aerial system in the related channel is reduced better on the premise of not increasing system bandwidth resources and unnecessarily reducing transmission rate. Compared with the traditional spatial multiplex multi-aerial system, only a rotation factor is multiplied at the transmitting end and the receiving end, and the coding method is low in hardware cost and excellent in error code performance.

The invention relates to a sonar image splicing method. The method comprises the steps of removing noise in order to increase the contrast ratio through image preprocessing; transforming a scaling parameter and a rotation parameter into translation parameters through carrying out log-polar transformation to an image amplitude frequency spectrum, and carrying out algorithm analysis based on phase correlation; filtering scale and rotation factors through image geometric transformation; working out the translation parameters through an algorithm based on the phase correlation; and carry out coordinate mapping through the scaling parameter, the rotation parameter and the translation parameters which are worked out, and carrying out image interpolation through a bilinear interpolation algorithm. The registration of all sonar images is achieved by continuously repeating the above steps, then the splicing of the sonar images is achieved through brightness adjustment and image superposed area fusion. According to the invention, the problem that the detection scope visual angle of sonar is narrow in an underwater monitoring process is solved, through sonar image splicing, a series of sonar images are spliced to a large-scale sonar image, and therefore the sonar can simultaneously monitor a large-scale underwater environment.

The invention discloses a velocity ambiguity resolving method suitable for a linear frequency-modulation continuous wave radar system. The method comprises the steps of firstly obtaining first echo data and second echo data according to an originally received intermediate-frequency signal; secondly, estimating a target distance and an ambiguous velocity and then determining a discrete Fourier transform rotation factor according to the target distance and the ambiguous velocity; thirdly, carrying out fast Fourier transform of a fast time dimension by using a reference signal and obtaining a slow time dimension complex vector of a distance unit at which the target is located according to the distance unit, at which the target is located, obtained in the first step; and finally multiplying the slow time dimension complex vector by the discrete Fourier transform rotation factor to find out a real unambiguous velocity corresponding to the maximum value. By creatively utilizing the concept of the least common multiple, a simple and effective velocity ambiguity resolving scheme is provided; the hardware implementation complexity is reduced; and a supportable guarantee is provided for parameter estimation and further operation of the whole system.

The invention relates to the technical field of mobile communication, and discloses a DFT algorithm for a ZC sequence in a PRACH channel of a LTE system. The DFT algorithm comprises the following process of: inputting a parameter k into an ROM1, and reading an output parameter k' of the ROM1; inputting a parameter u into an ROM2, and reading an output parameter u' of the ROM2; subtracting Nzc-1 from a value A obtained by adding k' with u' to obtain a parameter B; inputting A and B into a first selector, outputting a result according to a control signal, and inputting the result into an ROM3; reading output data of the ROM3, adding the output data with k to obtain a value C, and subtracting Nzc from the value C to obtain a parameter D; inputting C and D into a second selector, and according to a control signal, obtaining an output result of the second selector; adding a value E obtained after dividing the output result of the second selector by 2 and carrying out rounding with (with reference to the specification) to obtain a parameter F, inputting E and F into a third selector, taking a result G obtained by carrying out mod2 processing on the output result of the second selector as a control signal, and outputting a p value of a rotation factor index; and according to the p value, obtaining a DFT algorithm result of the ZC sequence. According to the scheme, the solving process of the p value is low in storage capacity, and the algorithm is simple.

The invention relates to a method for realizing 3780-point fast Fourier transform/inverse fast Fourier transform (FFT/IFFT) and a processor thereof. The processor consists of a top layer, an intermediate layer and a bottom layer, wherein the top layer resolves 3780-point by using a mixed based number algorithm, the intermediate layer resolves 63-point and 60-point FFT by using a prime factor algorithm, and the bottom layer complete 7-point, 9-point, 3-point, 4-point and 5-point FFT calculation by using a winograd fourier transform algorithm (WFTA) algorithm. The method realizes 3780-point FFT by combining the mixed base number algorithm, the prime factor algorithm and the WFTA algorithm, avoids errors caused by calculating 4096-point by using an interpolation method, and reduces rotation factors and a chaotic unit in the mixed base number algorithm. Furthermore, an index structure completed by a multiplex memory in the design has a simple circuit, is easy to realize, and can save chip resources.

Aspects of a system for STBC/SFBC in a communication system using angle feedback may include a receiver, which enables reception of signals via a plurality of receiving antennas. The receiver may enable computation of a rotation factor value based on the received signals and utilization of the computed rotation factor value to receive subsequent signals via the plurality of receiving antennas. The received signals may comprise preamble data. The receiver may enable computation of channel estimate values based on the received preamble data. A rotation angle value may be computed based on the computed channel estimate values. The rotation factor value may be computed based on the computed rotation angle value. The receiver may enable transmission of feedback information comprising the computed rotation factor and/or the computed rotation angle.

The invention discloses a circle quick door-opening device of a pressure container, which comprises an end enclosure, an upper flange and a lower flange which is connected with a tank body. The upper flange is arranged at a port of the end enclosure, the upper flange is evenly distributed with upper flange teeth along the circumferential direction, and the lower flange is evenly distributed with lower flange teeth along the circumferential direction. The device is characterized in that the device also comprises a circle which is arranged at the circumferential outsides of the upper flange and the lower flange, the upper end part of the circle is provided with upper teeth matched with the upper flange teeth to be locked, and the lower end part of the circle is provided with lower teeth matched with the lower flange teeth to be locked. Compared with the prior art, the device has the advantages that the locking and loosing of the circle are adopted for replacing the rotation of a quick opening cover, then relative rotation is not needed between the upper flange and the lower flange, and a sealing ring is abraded little; in addition, only the rising and falling of the quick opening cover are considered, the rotation factor does not need to be considered, so the requirement for the fixed structure of the quick opening cover is relatively less, and the manufacturing cost can be reduced.

The invention relates to a calibration method and a calibration device for touch screen equipment. A coordinate system rotation coefficient is determined according to the maximum pixel values of a first coordinate and a second coordinate of display equipment; according to the coordinate system rotation coefficient, a first preset point and a second preset point located at the display equipment, and a first touch point and a second touch point which are detected by the touch screen equipment when the first and the second preset points are touched, a first coordinate rotation coefficient and a second coordinate rotation coefficient are determined and a transforming relationship which transforms an initial coordinate system of the touch screen equipment into the transformed coordinate system of the touch screen equipment, with a coordinate system direction the same as that of the display equipment; according to the transforming relationship, the touch screen equipment can output the position coordinate of the transformed coordinate system, which has the same coordinate system direction as the display equipment, thus being convenient for transforming the position coordinate into the coordinate located at the display equipment and preventing the circumstance that the real touch position is different from the display position of the display equipment, which is caused by that when the touch screen equipment is installed on the display equipment, the direction is different.

The invention discloses a vehicle gear recognition method and device. The method includes the steps of building a vehicle body reference coordinate system and a gear reference coordinate system, collecting a vehicle body acceleration signal according to a built vehicle body coordinate system, and collecting a gear acceleration signal according to a built gear coordinate system. According to an Euler rotation transformation theory of a right-angle coordinate system, a rotation transformation relationship between the vehicle body coordinate system and the gear coordinate system is built, an equation relationship between a vehicle body acceleration vector and a gear acceleration vector is built according to the rotation transformation relationship between the vehicle body coordinate system and the gear coordinate system, a rotation factor between the gear reference coordinate system and the vehicle body reference coordinate system is solved according to the built equation relationship, and the rotation factor serves as a feature value for gear recognition. The method has the advantages of being simple in structure, easy to arrange and easy to achieve in a project. The state of a gear can be recognized when a vehicle runs under actual road conditions and a gear shifting motion is finished.

The invention relates to a base 2-. According to the fast Fourier transform hardware design method of the 2 algorithm, a frequency domain extraction mode is adopted, 16-point FFT of a base 22 algorithm of frequency domain extraction is obtained, a 16-point data flow diagram is obtained, and an overall structure of the base 22 FFT of 16 points based on a serial butterfly unit is designed; The structure comprises four processing stages, and each stage comprises a processing unit and an inverted sequence unit; Wherein the processing unit comprises a butterfly unit and a rotation factor multiplierunit. Each butterfly unit only comprises two adders, a serial butterfly unit of a real number adder and a subtracter is adopted, calculation is completed through two clock periods, addition and subtraction of a real part and an imaginary part are completed respectively, and a simple rotation factor multiplier and a complex rotation factor multiplier unit are designed for an odd number processingstage and an even number processing stage respectively.

The invention discloses method and device for processing data to be transmitted by adopting space-time coding by combining with precoding, which are applied to a base station with multiple transmitting antennas. The method comprises the following steps of: carrying out quasi-orthogonal space-time block code space-time coding with rotation factors on the data to be transmitted by the base station to generate multi-path coded data corresponding to the antennas in number; meanwhile, selecting a corresponding precoding mode by the base station according to speed fed back by a terminal and selecting a corresponding precoding codebook from a precoding codebook list stored in the base station by combining with the number of the antennas; precoding the multi-path coded data by the base station according to the selected precoding codebook and then outputting the coded data. The invention overcomes the constellation extension brought during carrying out the quasi-orthogonal space-time block code space-time coding so as to ensure that the data transmitted by the base station from the transmitting antennas can be self-adaptive to the conditions of channels.

The invention relate to the design of a prediction control method for a non-self-balancing system and mainly aims to solve the problems of difficult control on the non-self-balancing system, difficult modeling for the non-self-balancing system, difficult guarantee for the stability of a control system and irregular adjustment on parameters of a controller in the prior art. A single controller is adopted to only perform a step response test on a controlled target to obtain a prediction model of the target, and a prediction control algorithm is built by constructing control input of single freedom degree and introducing the concept of a rotation factor into a performance index by using a special error feedback correction method. The prediction control algorithm comprises the following steps of (1) building control input of single freedom degree: selecting future system control input which consists of one primary function weighing; (2) performing step signal excitation on the controlled target to obtain a process model; (3) building a future system expected performance index, and introducing the concept of the rotation factor into a performance index function; (4) deducing future prediction output; (5) building the special error feedback correction; and (6) ensuring the stability of the control system and tracing set value. Due to the adoption of the technical scheme, the problems are better solved, and the method can be used for operation control of the non-self-balancing system.

The invention belongs to the application field of software radio and digital signal processing thereof, in particular to a low-complexity multiplier-free fixed-point FFT optimization method based on dynamic truncation. The method includes obtaining FFT input data bits N and input data; shifting the decimal fraction of each rotation factor by N bits to the left, and dividing the data into a real part and an imaginary part, wherein N is the number of bits of the input data; rounding up the real part and the imaginary part up and down respectively, so that they are approximated to integers; All integers are factorized to the second power, and the integer with the least number of additions is selected; The circuit is designed by using shift and addition, and the multiplication of the originalrotation factor is replaced by the shift and addition of the data itself. The present invention further reduces the number of adders while replacing conventional complex multipliers with shift and add-subtract. At the same time, the dynamic bit-truncation module is added to restrain the growth of data bits, reduce the consumption of hardware resources, improve the computing speed and improve the performance of the circuit.

The invention relates to a generation method and device for a physical random accessing channel baseband signal. The generation method and device for the physical random accessing channel baseband signal can significantly reduce computation complexity and memory space. The method comprises the steps that a ZC root sequence corresponding to a physical random access channel is generated; the discrete Fourier transform is conducted on the ZC root sequence; subcarrier mapping and zero-filling are conducted on the output sequence of the discrete Fourier transform; the rapid inverse Fourier transform is conducted on the sequence after the mapping and zero-filling; first frequency spectrum shift is conducted on the sequence after the rapid inverse Fourier transform; sampling and filtering are conducted on the data after the conduction of the first frequency spectrum shift; second frequency spectrum shift is conducted on the data after sampling and filtering, wherein the rotation factor of the second frequency spectrum shift is the same as the rotation factor of the rapid Fourier transform with the length being Nsys.

Provided are a scrambling code generation method, apparatus and a scrambling code processing apparatus, the method comprising the steps of converting the inputted phase shift into a binary number, according to the position of the effective bit with the highest weight in the binary number to generate an access address of a rotation factor, according to the access address to select a corresponding rotation factor from a rotation factor table; mapping a K bits original scrambling code sequence to a 2K bits scrambling code sequence, and calculating the mapped scrambling code sequence with the rotation factor to obtain the rotated scrambling code sequence; updating the effective bit with the highest weight to zero; if the updated phase shift is zero, outputting the rotated scrambling code sequence, and if the updated phase shift is not zero, regarding the updated phase shift as the present inputted phase shift and the rotated scrambling code sequence as the original scrambling code sequence, and repeating the above processes. The solution improves the performance and the flexibility, furthermore has a lower cost.

The invention discloses a device and a method for implementing fast Fourier transform (FFT) and inverse fast Fourier transform (IFFT) operation. The device comprises an FFT/IFFT control unit, an arithmetic logical unit (ALU) operation unit, a random access memory (RAM) read/write control unit and a rotation factor reading unit, wherein the FFT/IFFT control unit is used for inputting two paths of data and rotation factors to be operated into the ALU operation unit, storing the ALU output calculation results into corresponding RAMs respectively and controlling the switching of butterfly operation of each stage of FFT/IFFT by using a state machine; the ALU operation unit is used for performing FFT/IFFT butterfly operation on the two paths of data to be operated respectively; the RAM read/write control unit is used for performing read and write control on a plurality of RAMs, wherein the plurality of RAMs store the FFT/IFFT butterfly operation results of each stage; and the rotation factor reading unit is used for calculating the storage address of the rotation factor required for calculating the butterfly operation of each stage in a rotation factor storage unit. The device improves the speed of FFT and IFFT in the prior art.

The invention relates to a linear frequency modulation continuous wave time-width ratio estimation method based on fractional Fourier transform and minimum pulse width detection. The method comprises:fractional Fourier transform is carried out on linear frequency modulation continuous wave signal data at different rotation factors to obtain a transformed sequence corresponding to each rotation factor; and Hilbert transform is carried out on the transformed sequence to obtain an envelope curve, a false alarm decision threshold is set and a minimum pulse width length is calculated, and a time-width ratio parameter estimation value of a target signal is obtained. According to the invention, high-dimensional complex calculation is not needed; the method is simple and is easy to realize; problems of multi-path delay and spectrum expansion caused by mutual interference between a direct wave and an indirect wave are solved effectively; a multi-path delay problem caused by multi-times reflection of the radar signal is solved; the operation load is reduced effectively and the estimation precision is improved; and the method has advantages of great practical application value, stable performance, and high reliability and efficiency.

The invention discloses a codebook generation method, a codebook generation device and a codebook generation system for a multiple-input multiple-output system, which relate to the technical field of wireless communication. The accuracy of a codebook and precoding performance are improved on the basis of not increasing a conventional codebook memory space of a receiver. The same preset codebook set is configured in two ends communicating with each other in the system. The method comprises the following steps of: obtaining an initial codebook; and when the quality of received signals is lower than preset quality, operating the initial codebook by utilizing a rotation factor and a rotation matrix to generate a new codebook, precoding a data stream by using the new codebook, and when the quality, estimated by utilizing the new codebook, of the signals meets the preset quality, transmitting the rotation factor to communication opposite-ends. The embodiment of the invention is mainly applied in the field of precoding codebook designing.

The invention discloses a fast Fourier converter, a reverse fast Fourier converter and a reverse fast method thereof. The fast Fourier converter is applied to Fourier conversion operation at the 3,780 point and comprises a sequence inserting device, a first conversion module, a rearranging module, a multiplying unit and a second conversion module, wherein the sequence inserting device receives aninput serial value and provides a plurality of point values to the first conversion module and the second conversion module, according to the requirements of the fast Fourier conversion operation; the first conversion module carries out the fast Fourier conversion operation at the 63 point and outputs the operation result to the sequence inserting device for temporarily storing the result; the rearranging module rearranges the result temporarily stored by the sequence inserting device; the multiplying unit multiplies each rearranged point value by a proper rotation factor; and the second conversion module performs the fast Fourier conversion operation at the 60 point on the multiplying result and generates an output serial value.