The Research of Virtual Multiple-input Multiple-output for the Uplink of LTE System
|School||Nanjing University of Posts and Telecommunications|
|Course||Communication and Information System|
|Keywords||LTE Multiple Input Multiple Output Semi - orthogonal user pairing algorithm System capacity Spectral efficiency Dispatch|
In the field of mobile communications , multiple input multiple output (MIMO) technology by the transceivers at both ends using a plurality of antennas to improve the capacity of the system as well as the spectral efficiency of the system . MIMO transmission scheme can be divided into two categories : spatial multiplexing and transmit diversity . Through spatial multiplexing , MIMO realized independently on each separate antenna to transmit a data stream . Assuming the number of receiving antennas is greater than the number of transmit antennas , the receiving side can be well separated from the signal area of these mixed . The purpose of spatial multiplexing is to improve the system capacity and spectral efficiency . Advantage of space division multiplexing -based MIMO system , the researchers made ??a series of virtual MIMO theory . Been widely applied in recent years in the LTE non-collaborative virtual MIMO technology , that is, via the base station to select a certain number of users to be paired such that the time / frequency resources without the need for direct communication between users having paired user can be shared . Though, through the uplink users share the same time / frequency resources can increase the capacity of the system , but to the individual users , matching affects the fairness and thus it will increase the bit error rate . The same time , if the channel state pairing between users there are significant differences , the channel state poor user performance to be greatly affected . Therefore, the choice of the appropriate user pair is not the key problem of collaborative virtual MIMO pairing algorithm . In this paper, for the LTE uplink virtual MIMO user pairing algorithm research based on the angle and on the the Frobenius norm two semi- orthogonal user pairing algorithm theoretical analysis on the basis of the SC-FDMA and MIMO combination the two algorithms simulation study in the case of fixed power allocation and adaptive power allocation . In turn based on an improved matching algorithm based on the SINR threshold fusion scheduling CA-SUP , the improved algorithm has a very good performance in terms of fairness and to increase system capacity .