31results about How to "Good spectral efficiency" patented technology

This invention provides a single-carrier blocking transmission method of frequency selective mode including the following steps: After setting up communications, M available sub-channels are found out from N sub-channel based on the channel state information after the receiving end estimates the channel state information available and forbidden sub-channels are labeled separately to form the sub-channel label information to be fed back to the sending end by the back channel. The sending end alters signal spectrums according to said received labeled information and transmits signals with the available sub-channels. The receiving end transforms the signals to frequency domain then to select signals on the available sub-channel then to balance the selected signals to be transformed to the time domain for judgment to get the transmitted date.

The invention provides a frequency spectrum admission control method based on cooperative frequency spectrum sensing. The method comprises the following steps: (1) through a cooperative scheme based on a secondary user group (SUG), self-adapting each secondary user SU to form SUGs; (2) for a cooperative sensing fusion strategy, carrying out calculation on a source node SUsor through a cooperative frequency spectrum sensing scheme so as to obtain an optimal value k under the situation of a given n value; and (3) for an acceptance control threshold of a cognitive radio network, analyzing an optimal acceptance control threshold, which can maximize throughput of the SUGs under the restriction condition of global false alarm probability, through a frequency spectrum acceptance control scheme based on cooperative sensing; and through solving of the optimal acceptance control threshold, finishing the whole optimizing process. According to the invention, the frequency spectrum frequency of the network is very well improved and the throughput of the SUGs can be also effectively increased; and the frequency spectrum acceptance control method based on cooperative frequency spectrum sensing, provided by the invention, is applicable to frequency spectrum access and frequency spectrum switching strategies in the cognitive radio network as well as corresponding performance analysis.

The invention discloses a digital pre-distortion processing method and device. The method and the device are used for effectively correcting a distortion characteristic of a power amplifier and solving the problem that existing DPD (Digital Pre-Distortion) processing performance is insufficient under a broadband signal. The method comprises the steps of determining a digital pre-distortion model according to an input signal and determining an output signal of the power amplifier according to the digital pre-distortion model, wherein the digital pre-distortion model comprises a conjugate cross term and a nonlinear memory term; and calculating a DPD coefficient according to the output signal.

This invention provides a bit loading method in a frequency selection single carrier blocking transmission system including the following steps: 1, The receive end gets balanced noise power according to the selected available sub-channel numbers M and their amplitude gain to get balanced S/N ratio in terms of the received S/N ratio and the balance way, 2,the receive end determines the applied different linear modulation ways, the data describing different linear modulation ways are called information of modulation way and sent to the send end via a feed back channel, 3, which images symbols and sends signals, 4, the receive end demodulates the signals and judges them.

The invention relates to a contract-based dynamic spectrum allocation method in a radio network. The method comprises the steps that: an authorization system counters the number of self idle channels, and defines a self revenue function; a cognition wireless link defines a self revenue function and reports self classification information to the authorization system; the authorization system solves an optimal quality set according to the classification information of the cognition wireless link; the cognition wireless link determines a corresponding optimal price set according to the solved optimal quality set; and the authorization system declares an optimal contract to all the cognition wireless links, and every class of cognition wireless links selects corresponding transmission power specified by the optimal contract. According to the method, channels are firstly considered to be dealt with different qualities, and each price is defined to each quality, thus greatly improving the benefit of the authorization system; and the optimal contract can realize the approximately complete optimal spectrum efficiency, and effectively reduce the interference among the authorization system and the cognition wireless links.

The invention provides a sea area large-scale antenna planar array beam selection and user scheduling method, and relates to the technical field of sea area scheduling. The method comprises the stepsas follows: R1, a shipborne AIS system performs information interaction with a shore-based base station equipped with a large-scale antenna planar array, and acquires position information of each user; and then height information of the shore-based base station and height information of a ship terminal are acquired via a height indicator; R2, a sea area range covered by beams corresponding to thelarge-scale antenna planar array is divided according to the user position information, and the height information of the shore-based base station and the ship terminal acquired in the step R1, and each user is divided into each corresponding beam; R3, the user with the highest priority is selected from each beam, and sequentially put into the set of users to be served; and R4, in each schedulingperiod, the user in the set of users to be served is scheduled according to a system weight and rate maximization criterion for service, and the unused beams are closed. According to the method provided by the invention, the beam selection and user scheduling speed is fast, and the algorithm complexity is low.

This invention puts forward a receiving and test method for a vertical lamination space time system based on adaptive modulation, which first of all tests channels with the modulation system reaching the maximum saturation, then tests the invalid channels with SN ration can't meet the lowest threshold, finally tests the residual sub-channels according to the principle of the priors with the SN ratio approaching to the threshold value after detection, which can make the tested SN ratio to satisfy the SN-ratio threshed value properly, so, channel resources can be used to the utmost.

The invention discloses a hybrid precoding method for a millimeter-wave large-scale MIMO system, and the method comprises the steps: 1, carrying out the channel modeling, determining a channel matrix H, and carrying out the singular value decomposition of the channel matrix to obtain an optimal unconstrained all-digital precoding matrix; 2, constructing an analog precoding vector by adopting an alternate iteration method; 3, updating a residual matrix Fres by adopting a mode similar to matching pursuit; 4, calculating a digital precoding matrix by adopting a least square method and carrying out normalization processing; and 5, obtaining an analog combination matrix and a digital combination matrix at a receiving end by adopting the same steps. According to the invention, the optimal spectral efficiency close to that of the all-digital precoding method can be obtained with relatively low calculation complexity, so that the channel capacity close to that of all-digital precoding can be obtained, and the energy consumption of a radio frequency chain is greatly reduced.

The invention discloses a lower voltage power carrier transmission algorithm. The low voltage power carrier transmission algorithm distributes bits according to power line carrier communication sub channels, and on the premise of keeping a target error bit rate, the spectrum efficiency of a system achieves the best; the algorithm firstly enables the performance of the system to achieve a best threshold, then, determines the modulation mode of each sub carrier, and finally, adjusts the power of the sub carriers.

The invention discloses a hybrid precoding algorithm based on a gradient descent method, and particularly relates to a hybrid precoding algorithm for a partially connected phase shifter network in large-scale MIMO. The invention aims to independently optimize analog domain precoding under the condition that digital domain precoding is fixed so as to reduce the algorithm complexity. The method comprises two parts: 1, solving a baseband precoder and a combiner by using a least square method under the condition of randomly giving a precoder of an analog domain; 2, proposing an algorithm for solving the analog precoder and the combiner by using a gradient descent method; According to the gradient descent method provided by the invention, the algorithm complexity can be effectively reduced under the condition that the spectral efficiency is kept optimal, and the method has the advantage of rapid convergence. Meanwhile, the method is suitable for phase shifter networks with different resolutions, and the algorithm flexibility is higher.

The invention relates to a TDD large-scale MIMO system pilot frequency allocation method based on alliance game. Compared with the prior art, the TDD large-scale MIMO system pilot frequency allocation method has the advantages of solving the defect of relatively large difference between an analysis scene and an actual application scene in the pilot frequency allocation method. The TDD large-scale MIMO system pilot frequency allocation method comprises the following steps: preprocessing user data; establishing a sub-alliance structure; and obtaining a pilot frequency allocation result. The idea of alliance game is imported into the pilot frequency allocation based on user grouping, which is not only suitable for the scenes in which the cell shape is not regular and the number of users in each cell (the users are randomly distributed), but also can effectively relieve the pilot frequency pollution effect, and can relieve the problem that the existing method for solving the pilot frequency pollution effect is hard to be actually used.

The invention discloses a handheld wireless ad hoc network communication device. A baseband processing module of the handheld wireless ad hoc network communication device comprises: a modulator/demodulator which is used for modulating/demodulating a signal frame; the modulator/demodulator adopts an OFDM (Orthogonal Frequency Division Multiplexing)/OQAM (Open Quadrature Amplitude Modulation) modulation/demodulation mode, various problems of handheld ad hoc network communication equipment in the prior art are solved, and real number symbols, real parts and imaginary parts which are subjected tooffset processing are modulated and sent instead of complex symbols; the handheld wireless ad hoc network communication device has excellent performance in the aspects of spectrum efficiency, ICI resistance, out-of-band radiation and the like, and solves the problems in the prior art.

The invention relates to the technical field of large-scale MIMO (Multiple Input Multiple Output) communication, in particular to a hybrid precoding algorithm based on millimeter wave large-scale MIMO multi-user scenarios, which is an algorithm for hybrid precoding in large-scale MIMO by adopting an adaptive connection network and mainly comprises the following steps of: designing an analog precoder and giving the analog precoder; and receiving and solving the baseband precoder through MMSE. By optimizing the analog precoder, the spectral efficiency is maximized. Meanwhile, according to the algorithm provided by the invention, the cost and the complexity of the algorithm can be further reduced on the premise of meeting the performance.

The generalized rate division multiple access (G-RSMA) technology has the potential of remarkably improving the energy efficiency EE and the spectral efficiency SE of the wireless network. In order tomaximize the energy efficiency EE and the spectral efficiency SE of a multi-cell MISO system, the invention provides a joint design of a beam forming vector and rate allocation by applying a G-RSMA technology, and establishes a multi-objective optimization problem of maximizing the energy efficiency EE and the spectral efficiency SE at the same time. According to the method, the proposed multi-objective optimization problem is converted into a single-objective optimization problem to realize EE-SE trade-off, and the maximum energy efficiency EE can be obtained in any reachable spectral efficiency SE area by further researching the pseudo-convex relationship between the energy efficiency EE and the spectral efficiency SE. Simulation results prove that under different system parameter settings, compared with a traditional multiple access technology, the energy efficiency EE of the system is improved under the condition that the ideal spectral efficiency SE is obtained.

The invention discloses a millimeter wave joint beam selection and power distribution optimization method, which utilizes increment and decrement algorithms to carry out matrix reconstruction on non-shared beams appearing under different grouping conditions so as to realize a joint beam selection and power distribution optimization scheme with low complexity and high spectrum efficiency. A non-convex objective function is converted into a convex objective function by using a Sherman-Morrison-Woodbury formula and a minimum mean square error function, a non-linear condition in constraint conditions is converted into a linear condition by converting a feasible region of the objective function, a new convex optimization model is enabled to meet a Karush-Kuhn-Tucker condition by using a dual Lagrange function, the optimal power distribution factor is deduced, and iterative updating of the optimal power distribution factor is carried out, so that the user signal in each beam can be distributed to an optimal power value.