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

The invention discloses a distributed Alamouti coding cooperative transmission method based on quasi-orthogonal channel allocation, which mainly solves the problem that the traditional method can not simultaneously take the reliability and effectiveness of a system into consideration. In the implementation process of the method, a relay cooperative communication system is set; in a first time slot and a second time slot, a sender S respectively broadcasts signals x1 and x2, and relays R1 and R2 respectively receive signals yr11k, yr21 and yr12, yr22,; in a third time slot, the relays R1 and R2 respectively transmit signals ayr11 and -ay<*>r22 to a receiver D on the same channel, wherein a is an amplification factor, and ()* is complex conjugate; the sender S transmits a signal -x<*>2 to the receiver D on the orthogonal channel with the R1 and the R2; and in a fourth time slot, the relays R1 and R2 respectively transmit signals ayr12 and ay<*>r21 to the receiver D on the same channel, the sender S transmits a signal x<*>1 to the receiver D on the orthogonal channel with the R1 and the R2, and the receiver D carries out maximal likelihood decoding on the received signals. The invention can ensure that the system achieves performance compromising between false symbol rate and spectral efficiency and simultaneously takes the reliability and the effectiveness of the communication system into consideration.

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 relates to a pilot allocation method for a TDD large-scale MIMO system based on an alliance game, and solves the defect that the analysis scene of the pilot allocation method has a large gap with the actual application scene compared with the prior art. The invention includes the following steps: preprocessing of user data; establishment of sub-alliance structure; acquisition of pilot allocation results. The present invention introduces the idea of ​​alliance game into pilot allocation based on user grouping, which is applicable to scenarios where the cell shape is irregular and the number of users in each cell is not fixed (users are randomly distributed), and can effectively reduce pilot pollution. It alleviates the problem that the existing method for solving the effect of pilot pollution is difficult to be practically applied.

The present application provides a method for beam selection and user scheduling of a large-scale planar antenna array in a sea area, which relates to the technical field of sea area scheduling. Step R1, the shipborne AIS system interacts with the shore-based base station equipped with a large-scale antenna planar array to obtain the location information of each user; then obtain the height information of the shore-based base station and the height information of the ship terminal through the altimeter. Step R2, according to the user position information obtained in step R1, the height information of the shore-based base station and the ship terminal, divide the sea area covered by the beam corresponding to the large-scale antenna planar array, and divide each user into each corresponding beam; step R3. Select the user with the highest priority in each beam, and put it into the user set to be served in turn; Step R4. In each scheduling cycle, schedule the users in the user set to be served for service according to the system weight and the maximum rate criterion, Turn off unused beams. In this application, beam selection and user scheduling are fast, and algorithm complexity is low.