Design Of Time Domain Mimo Channel Sounder And Implementation Of Data Transmission Module

Multiple-Input Multiple-Output (MIMO) technology is a kind of wirelesscommunication technology that both transmitter and receiver use a plurality ofantennas respectively. The core idea of MIMO is using spatial degree of freedombetween multiple transmit antennas and multiple receive antennas to effectivelyimprove the spectrum utilization, the transmission rate of wirelesscommunication system, and finally to improve the communication quality.Channel characteristics have important effect on the performance ofcommunication system. These excellent properties of MIMO technology areproposed on the assumption that the channel is ideal. Channel characteristicsunder different environments or frequency band differ even vary greatly, soobtaining characteristics of the channel by measuring is needed. Existing channelmeasurement platform includes time domain measurement platform andfrequency domain measurement platform. Channel measurement platform basedon frequency domain usually can not be used in high-speed time-varying channelmeasurement. Larger signal bandwidth will be used in the future communicationsystem and most of the measurement platform based on the time-domain can notmeet the future requirement for the communication channel measurement. In thispaper, MIMO channel sounder based on sliding correlation theory in time domainis designed, which can measure high-speed time-varying channel and quicklyextract channel parameters. Besides due to it integrates transfer and receivertogether, it is smaller than other exiting MIMO channel sounders.In order to meet the future requirement of the communication channelmeasurement, measurement platform based on time-domain will use a largersignal bandwidth, which will produce a large number of base-band data.Therefore, the platform needs to design a high-speed data transmission module totransfer data to the PC memory for storing and further processing. PXI Expressinstrumentation bus is an extension of PCI Express bus in the field of theinstrument, and is the fastest bus interface form on data transfering rate currentlyused in the field of instrument. In this paper, time domain measurement platformdata transmission module is designed using PXI Express instrumentation bus,which has functionality of transmitting a large number of baseband data to PCmemory.In this paper, relevant outcomes on MIMO radio channel characteristicmeasurement abroad is studied firstly. Then according to the theoretical modeland the project requirement, related technical indicators of time domain MIMO channel measurement platform are designed. Secondly the simulation of usingsliding correlation method in time domain to extract channel impulse response isachieved, and the result shows that the method is suitable for the platform design.Thirdly the PXI Express instrument bus architecture and hardware structure isanalyzed and the entire system hardware circuit is also designed. Finally, designscheme and processes using PXI Express instrumentation bus to design themeasurement platform are analyzed and proved, and ultimately hard-coresingle-chip hardware architecture and embedded design method are used toachieve a platform for data transmission module design and implementation.