Research And Implementation Of MIMO-OFDM System With The Key Technology Of Physical Layer Using NI USRP-RIO

In recent years,software radio technology has been became one of the hotspots of future wireless communications research.Because of the powerful features and flexibility,using software radio technology can achieve the rapid upgrading of wireless networks.At present,there are many kinds of software radio platforms on the market for research and development.The USRP-RIO software radio platform developed by NI has been widely used in wireless communication because of its good openness and strong interactivity.In order to build a reliable wireless communication system on the USRP-RIO platform and verify the communication algorithm of the large-scale MIMO system on this system,in this paper,the SISO-OFDM and 2×2MIMO-OFDM systems are quickly constructed by NI's USRP-RIO software radio platform and LabVIEW software,and the constructed communication system are tested and analyzed.The main work done is as follows:1.Based on NI's USRP-RIO software radio platform,the transmitter and receiver of SISO-OFDM system physical layer are design.The IFFT modulation/FFT demodulation,synchronization,frequency offset correction,frequency domain LS channel estimation and ZF signal detection are discussed and implemented by the software,and the concrete block diagrams are given.Then the transmitter and receiver of the system were tested in the simulation channel.Finally,analysis the experimental data to verify the feasibility and reliability of the SISO-OFDM system on the software radio platform.From the front panel of the receiver VI can be seen after the balanced receiver constellation can analyze and clearly show the data,the receiver bit error rate of 10-6,which proved based on the USRP-RIO platform to build SISO-OFDM system has strong feasibility and reliability of receiving data.2.Based on the SISO-OFDM system,a 2×2 MIMO-OFDM system is proposed.The transmitter of the system increases the horizontal space-time stratification coding,the signal detection module of the receiver also adds two non-linear detection algorithm: ZF-SIC detection algorithm,ZF-OSIC detection algorithm,and the 2×2MIMO-OFDM system is implemented by the software.Then verifies the correctnessof the designed transmitter and receiver in the simulation channel.Finally,analysis the experimental data to verify the feasibility and reliability of the 2×2MIMO-OFDM system on the software radio platform.3.The performance of ZF algorithm,ZF-SIC algorithm and ZF-OSIC algorithm is analyzed and verified in the real 2 × 2 MIMO-OFDM system.The results show that ZF-OSIC algorithm is superior to ZF-SIC algorithm and ZF algorithm,which is the worst performance of ZF algorithm,whether it is LabVIEW simulation channel or real channel.However,the ZF-OSIC algorithm can improve the performance of the system at the expense of computational complexity.Therefore,in practical application,the appropriate detection algorithm can be selected according to our own requirements.