| As the popularity of global informatization,the demand in precision of signals becomes higher.A new kind of Matrix pencil method,MPM,and developing neural network offers a new idea and method to multipath suppression.This paper focuses on discussing the estimation of multipath suppression based on a new Matrix pencil method and developing neural network.The data comes from simulation by using microwave software.At first,the paper puts forward a new matrix method based on measurement with single-frequency point in order to prevent the instability of the number of multipath bringing by different frequencies.And then,it introduces the fast-developing neural network,and bringing neural network into measurement.At last,according to the actual requirement of Ku-band radio communications and mobile satellite communication,raising the idea of bringing new algorithm based on MPM and NN into communication system,and analyzing the feasibility.Research mainly divides into three aspect:1.Putting forward a new matrix method based on single frequency point measurement.In this research,a dipole is experiment antenna.The rectangular plane perpendicular to the direction of wave propagation is the sample surface.Put the origin of coordinates as the starting point and sampling eight points according to forward direction of x-axis and y-axis.The sampling unit is 0.03 m.Calculating the basic parameters of multipath and the interference factor Bp with MPM,Fourier transform and Convolution Algorithm,and outputting signals without multipath.In order to generate multipath,put a baffle-board as the source of reflected signals.The board is made of PEC here.It is easy to demonstrate the efficiency of the algorithm by describing the result of suppression.Cause the material of reflector bring little affect into reflect signal,the capacity of recognizing signal with small difference can be explored by adding Aluminum plane reflector and Copper plane reflector and comparing the result with the one of PEC plane reflector.The result shows the algorithm is not sensitive to signal with small difference.And then in order to explore the capacity of recognizing signal with large difference,comparing the signal resulted from system of PEC concave reflector,PEC Convex reflector and PEC plane reflector.Results show that the algorithm is similar to a quantitative calculation.The bigger multipath interference is,the better of the suppression effect.2.Putting forward an measurement based on NN.Just like the one before,a dipole is experiment antenna.The x-axis in the rectangular plane perpendicular to the direction of wave propagation is the sample line.Put the origin of coordinates as the starting point and sampling ten points according to forward direction of x-axis.The sampling unit here is 0.1 m.This method need to measure two time in one point that one is with baffle-board and the other one is without baffle-board.And in NN system,the data of signal with multipath is input signal and the signal without multipath is the output one.By using these two kind of data,the NN system can be trained.And then,choosing a point arbitrarily in the rectangle plane,and put into the NN system to prove the practicability.As the same,adding two system consist of reflect made of Aluminum and Copper,and comparing the result with the one come from system equipped with PEC,the result show that the algorithm based on NN can recognize signal with small difference and suppress effectively.Meanwhile,by comparing the figure from system with PEC concave reflector,PEC Convex reflector and PEC plane reflector,it can be seen that the performance of algorithm is always excellent.3.Putting forward an idea of bringing MPM system and NN system in Ku-band radio communications and mobile satellite communication.After introducing the structure of these two system,and analyzing possible source of multipath mainly reflected signals in the systems,creating an effective model of receiving signals.At last,proving the feasibility of using these two method in the systems. |
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