Study Of MIMO Transmission System For Multimode-waveguide Based Interconnect

With the rapid development of information technology and communication industry,people gradually turn their attention to the optical transmission system,because the optical transmission system has a high transmission capacity,anti-interference ability and so on.Optical interconnection,including free space optical interconnection,inter-board optical interconnection and waveguide interconnection.Among them,waveguide interconnection is of great significance to the development of future on-chip multi-core system.In order to improve the transmission capacity of optical transmission system,people researched and applied wavelength division multiplexing(WDM),multi-order modulation,polarization multiplexing,mode-division multiplexing(MDM)and other technology,and also introduced multi-input multi-output(MIMO)technology.These technology have made significant progress in long-haul fiber transmission systems,but other optical transmission systems,such as multimode waveguide interconnect,develops relatively slowly.This paper studies the MIMO transmission system based on technology combined with waveguide coupling devices,,which can improve the transmission system performance.Besides,it is also significant to study the on-chip optical interconnection system to analyze the performance of the transmission system.First of all,the test platform of the MIMO transmission system for multimode waveguide interconnection is built.The test platform is mainly composed of software defined radio(SDR)module,electro-optical modulation module,multi-port waveguide coupling module and photoelectric detection module.SDR module can generate electrical signals for two channels,sending them through the electro-optical modulation module to the multi-port waveguide module.The coupling module can control the crosstalk of the two optical signals by voltage,to realize different channels with different crosstalk.Finally the optical signals are converted into the electrical signals through the photoelectric detection module,and the received data are processed and analyzed.Based on the test platform,this paper analyzes the performance of the MIMO transmission system,mainly analyzes the effect of the channel estimation algorithm,the effect of different MIMO algorithms,the relationship between channel crosstalk and bit error rate,the effect of different signal to noise ratio(SNR)and so on,which are compared with the simulation results.Through the analysis,it can be concluded that the effect of the channel estimation algorithm is acceptable.Different MIMO algorithms improve the performance of the system to different extent.At the same SNR,the bit error rate(BER)is higher with excessive channel crosstalk.At the same crosstalk level,the system performs better at higher SNR.