Mårten Sundberg

Improved Latency Performance with GSM/EDGE Continued Evolution

The worlds largest and most widespread cellular technology today is GSM/EDGE. EDGE is capable of offering an attractive solution for 3rd generation cellular services in existing GSM networks. However, the introduction of new and more delay sensitive services may require improved latency performance. Reducing the delay and increasing the bandwidth efficiency in EDGE systems is important for services with stringent latency requirements, such as conversational VoIP, but will be beneficial also to other services. Proposed is to reduce the transmission time interval from 20 ms to 10 ms, in combination with novel procedures for faster feedback. Simulation results show that LLC delays may be reduced by 20-40% depending on traffic scenario. Furthermore, channel resource requirements for VoIP could be substantially reduced.

Chapter 1 – The Cellular Internet of Things

This chapter introduces the overall content of the book. It contains a brief introduction to the massive Machine-Type Communications (mMTC) category of use cases, spanning a wide range of applications such as smart metering and wearables. When discussing these applications, special attention is given to the service requirements associated with mMTC, for example, in terms of reachability, throughput, and latency. The chapter continues and introduces the concept of the Cellular Internet of Things (CIoT) and the three technologies Extended Coverage Global System for Mobile Communications Internet of Things (EC-GSM-IoT), Narrowband Internet of Things (NB-IoT), and Long-Term Evolution for Machine-Type Communications (LTE-M) that can be said to define this concept. While EC-GSM-IoT and LTE-M are backward compatible solutions based on GSM and LTE, respectively, NB-IoT is a brand new radio access technology. The final part of the chapter looks beyond the set of cellular access technologies and introduces the Low Power Wide Area Network (LPWAN) range of solutions that already have secured a significant footprint in the mMTC market. Unlike the cellular systems, these LPWANs have been designed to operate in licensed exempt spectrum. An initial discussion around the pros and cons of licensed exempt operation is presented to prepare the reader for the final chapters of the book, where a closer look is taken at operation in the unlicensed frequency domain.

Higher Order Modulation and Turbo Coding for GSM/EDGE Continued Evolution

GSM/EDGE is the worlds largest and most widespread cellular technology. EDGE offers an attractive solution for 3rd generation cellular services in existing GSM networks. The introduction of new services into an existing network typically leads to increased capacity demands, since more users of different service types need to coexist in limited spectrum, while the existing speech service is required to function at least as well as before. Higher Order Modulation in combination with Turbo Coding is proposed to substantially enhance spectrum efficiency and average user bit rates in GSM/EDGE through improved interference robustness and increased peak bit rates. Simulation results indicate link level gains of 2.5-5.5 dB. When additionally applying incremental redundancy, similar relative improvements are shown. Bit rates can be increased by more than 30%, at C/I levels above 30dB. System performance gains are indicated by average user bit rate enhancements of up to 30-40%, along with substantial gains in spectrum efficiency, up to 40%. It is also shown that system gains are rather insensitive to frequency reuse and whether frequency hopping is applied or not (in sparse reuse scenarios).

NB-IoT Performance

This chapter presents the Narrowband Internet of Things (NB-IoT) performance in terms of coverage, data rate, latency, battery lifetime, and system capacity. All these performance aspects differ between the three operation modes of NB-IoT. Thus, in most cases the performance of each NB-IoT operation mode is individually presented. It shows that all the three operation modes of NB-IoT meet the Third Generation Partnership Project (3GPP) performance objectives agreed for Cellular IoT.

Chapter 10 – 5G and the Internet of Things

This chapter describes the evolution of mobile networks toward 5G. Beyond an evolution of the mobile broadband experience, 5G will provide optimized connectivity for MTC and IoT services. An overview of the standardization activities toward massive Machine-Type Communications (mMTC), as well as critical Machine-Type Communications (cMTC), with Ultra Reliable and Low Latency Communications (URLLC) is presented.

EC-GSM-IoT

Abstract This chapter presents the design of Extended Coverage Global System for Mobile Communications Internet of Things (EC-GSM-IoT). The initial section describes the background of the GSM radio access technology, highlighting the suitability of an evolved GSM design to support the Cellular IoT (CIoT) core requirements, which includes ubiquitous coverage, ultra-low-device cost, and energy efficient device operation. The following sections builds from the ground up, starting with the physical layer, going through fundamental design choices such as frame structure, modulation, and channel coding. After the physical layer is covered, the basic procedures for support of full system operation are covered, including, for example, system access, paging functionality, and for EC-GSM-IoT-improved security protocols. The reader will not only have a good knowledge of EC-GSM-IoT after reading the chapter but will also have a basic understanding of what characteristics a system developed for CIoT should possess. At the end, a look at the latest enhancements of the EC-GSM-IoT design is presented.

Chapter 6 – LTE-M Performance

Abstract This chapter presents Long-Term Evolution for Machine-Type Communications (LTE-M) performance in terms of coverage, data rate, latency, and system capacity based on the 3GPP Release 13 functionality described in Chapter 5 . The methods and assumptions are to a large extent following those used for Extended Coverage Global System for Mobile Communications Internet of Things (EC-GSM-IoT) and Narrowband-IoT (NB-IoT) performance evaluations as described in Chapters 4 and 8 Chapter 4 Chapter 8 . When there are differences, those are explicitly described in this chapter. The reduction in device complexity achieved by LTE-M compared to earlier 3GPP releases of LTE is also presented. While LTE-M has been specified for both half-duplex frequency-division duplexing (HD-FDD) and full duplex FDD (FD-FDD) operation as well as time-division duplexing (TDD) operation, this chapter focuses on the performance achievable for LTE-M in HD-FDD operation.