摘要：低功耗广域网（LPWAN）当下是物联网领域中最受关注的技术之一，它具备功耗低、覆盖范围广、支持大量连接的特点，能够满足众多物联网应用的需求。本文以LPWAN技术为切入点，分别讨论了采用非授权频谱的Sigfox、LoRa的技术概况、关键技术并进行总结，对LoRa的Chirp扩频技术进行仿真，并讨论其抗噪声性能。接着讨论采用授权频谱的NB-IoT的技术概况、传输方案、部署方式、物理层设计、HARQ操作，并通过与LTE作对比来对NB-IoT进行性能分析。本文的研究重点为NB-IoT，而NB-IoT的第一步，也是最重要的一步便是NPSS信号的检测。因此本文接下来对NPSS信号的设计与检测进行仿真，讨论频偏和噪声对检测的影响并给出解决方案。

关键词低功耗广域网SigfoxLoRaNB-IoTNPSSChirp扩频

Title Power-efficient waveform for low power IoT             

Abstract：Low Power Wide Area Network (LPWAN) is one of the most popular technologies in the field of Internet of Things (IoT). It has the characteristics of low power, wide coverage and support massive connections to meet the needs of various IoT applications. In this thesis, staring with LPWAN, we first discuss the key technologies of Sigfox and LoRa that operate on the unlicensed spectrum and make a conclusion. Next, the simulation of LoRa's Chirp spread spectrum technology and its anti-noise performance are discussed. Then we discuss the background, transmission scheme, deployment scenarios, physical layer design, HARQ operation of the NB-IoT that operates on the licensed spectrum, and analyze the performance by comparing with LTE. The focus of this paper is NB-IoT, and the first and foremost part of the NB-IoT is the detection of NPSS signal. Therefore, this thesis then simulates the design and detection of NPSS signal, and discusses the influence of frequency offset and noise on the detection and gives the solutions.

Keywords  LPWAN  Sigfox  LoRa  NB-IoT  NPSS  Chirp spread spectrum

目 次

1 绪论 1

1.1 低功耗物联网简介 1

1.2 论文结构 2

2 采用非授权频谱的LPWAN接入技术 3

2.1 Sigfox 3

2.2 LoRa 4

3 Chirp扩频技术 7

3.1 Chirp扩频原理 7

3.2 LoRa中的Chirp扩频 8

3.3 抗噪声性能分析 10

4 采用授权频谱的LPWAN接入技术——NB-IoT 12

4.1 技术概况 12

4.2 传输方案 12

4.3 部署方式 13

4.4 物理层设计 14

4.5 HARQ操作 19

4.6 LPWAN的LoRa的Chirp扩频技术仿真:http://www.chuibin.com/tongxin/lunwen_205623.html