A Cross-Layer Design Of Combining Raptor Code And RPC

In the traditional communication system,in order to ensure the robustness of the system,it is necessary to decouple the protocol layers,and this idea is not optimal in the wireless communication scene with variable channel conditions.The information interaction between protocol layers allows the communication system to coordinate the transmission parameters of each layer to better adapt to the channel change,thus enhancing the system transmission efficiency.Therefore,this paper uses RPC(Random Projected Coding)to improve the channel adaptability and Raptor code coding indifference,the Raptor code applied to the data link layer,RPC application in the physical layer,the joint data link Layer and physical layer proposed a cross-layer design,the program to ensure smooth transmission of the system at the same time,to enhance the overall system throughput.In view of the advantages of RPC technology with excellent channel adaptability and simplification of system feedback and feedback content design,this paper applies it to the physical layer and establishes the error rate model.Raptor code is a kind of no rate code It is effective to deal with the physical layer packet loss,this paper will be applied to the data link layer and the establishment of codec model.Based on the above model,this paper designs a cross-layer design scheme combining Raptor code and RPC.By combining the decoding capability and decoding of the data link layer and the physical layer,the Raptor code reordering and the coding rate of RPC are unified by the system,To maximize system throughput.Theoretical analysis and practical simulation results show that the scheme has 10%-25% improvement in system throughput performance compared with non-cross-layer design.At the same time,the traditional wireless communication in the physical layer of the wrong packet will be regarded as a direct dropout packet loss caused by a serious waste of transmission resources,in view of Raptor code in the deletion of channel and noise channel two applications have different decoding methods,In this paper,we propose a cross-layer design scheme based on mixed decoding.The core idea is to use the BP decoding algorithm of Raptor code to fully exploit the useful information carried in the error packet after the physical layer RPC decoding,combined with the Raptor code The Gaussian deconvolution algorithm composes a mixed decoder to reduce the waste of resources caused by the direct packet loss of the physical layer,thus improving the system throughput.The actual simulation results show that the proposed scheme achieves up to 12% improvement in system throughput compared to the previous cross-layer design without mixed decoding.