Design And Performance Evaluation Of New LPWAN Interleaver

With the continuous development of the Internet of Things,the terminal volume of the Internet of Things has entered a stage of rapid growth.As an emerging technology,LPWAN has great prospects.However,the current LPWAN system still has the problems that the system capacity cannot meet mass access requirements in future,and at the same time,the equipment cost is high and the user access success rate is low.To address these issues,our group have proposed a new LPWAN system based on Massive MIMO technology.This article focuses on the design and performance evaluation of the interleaver to be used in the system:1)According to the analysis of application scenarios of LPWAN system,this paper points out five major design requirements of the interleaver performance: good frame error rate performance,high degree of interleaving dispersion,support for interleaving before puncturing,support for high-order modulation,and low complexity.Among them,the frame error rate performance cannot be weaker than the interleaver of WLAN,4G and 5G system.2)This paper proposes the design and performance evaluation scheme of the new LPWAN interleaver.The interleaver in this paper is a segmented block interleaver with a fixed number of columns.The design of the address generator enables the interleaver in this paper to meet the requirements of performance requirement.3)In this paper,the six performances of the four interleavers are compared and evaluated through simulation.The simulation results show that the interleaver in this paper meets the design requirements in six major performances: it has a frame error rate performance that is not weaker than that of the other three interleavers,and it performs better among them;The degree of interleaving dispersion is the highest without segmentation;by increasing the number of segments,the degree of interleaving dispersion can be further improved;the only interleaver that supports interleaving before puncturing;supports high-order modulation,which has better performance under high-order modulation;the algorithm complexity is lower,and the four interleavers have no complexity obvious gap.