{"title":"An Index-Modulated FSCM Systems with Low Complexity Algorithm and Enhanced Data Rate","authors":"Li Li;Zujun Liu;Yurong Guo","doi":"10.23919/comex.2024XBL0011","DOIUrl":null,"url":null,"abstract":"Frequency-Shift Chirp Modulation (FSCM) also known as LoRa modulation, enables long-distance transmission with low power consumption for Internet of Things (IOT), but has a limited transmission rate. Frequency-shift chirp spread spectrum system with index modulation (FSCSS_IM) introduces index modulation to improve the transmission rate of FSCM at the cost of high demodulation complexity. This letter propose an improved FSCSS_IM scheme to further improve the transmission rate of FSCM by adding indexes with equal values to the codebook. And then we design a low complexity demodulation algorithm which employs index matching to replace the index search matching algorithm in FSCSS_IM. Finally, we derive the approximate BER expression of the proposed scheme. The analysis and simulation results show that the transmission rate of the proposed scheme is up to 91.7% higher than that of the FSCM and 8.3% higher than that of the existing FSCSS_IM scheme, and the demodulation algorithm has the almost the same computational complexity as the FSCM and much lower than that of FSCSS_IM.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 4","pages":"138-141"},"PeriodicalIF":0.3000,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10439041","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"IEICE Communications Express","FirstCategoryId":"1085","ListUrlMain":"https://ieeexplore.ieee.org/document/10439041/","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ENGINEERING, ELECTRICAL & ELECTRONIC","Score":null,"Total":0}
引用次数: 0
Abstract
Frequency-Shift Chirp Modulation (FSCM) also known as LoRa modulation, enables long-distance transmission with low power consumption for Internet of Things (IOT), but has a limited transmission rate. Frequency-shift chirp spread spectrum system with index modulation (FSCSS_IM) introduces index modulation to improve the transmission rate of FSCM at the cost of high demodulation complexity. This letter propose an improved FSCSS_IM scheme to further improve the transmission rate of FSCM by adding indexes with equal values to the codebook. And then we design a low complexity demodulation algorithm which employs index matching to replace the index search matching algorithm in FSCSS_IM. Finally, we derive the approximate BER expression of the proposed scheme. The analysis and simulation results show that the transmission rate of the proposed scheme is up to 91.7% higher than that of the FSCM and 8.3% higher than that of the existing FSCSS_IM scheme, and the demodulation algorithm has the almost the same computational complexity as the FSCM and much lower than that of FSCSS_IM.