The first release of 5G NR (Rel-15) supports Internet of Things (IoT) use cases including ultra-reliable low-latency as well as massive machine type communications. In Rel-17, reduced capability devices are being introduced to support mid-range IoT use cases such as industrial wireless sensors, wearables, and video surveillance. These use cases require low-cost devices to support high reliability, low latency, medium data rate, and long battery life despite being low complexity in design. In this paper, we provide an overview of these devices and describe important features being standardized in 3GPP for complexity reduction, coverage compensation, and power saving.

The support for Internet of Things (IoT) has evolved over several successive releases of standard specifications in 3GPP. As a result, eMTC and NB-IoT are mature 4G wireless technologies that are seeing largescale deployment. Thus, even as 4G systems migrate to 5G New Radio (NR) technology, there is a strong motivation to continue to support eMTC devices through efficient deployment of eMTC within a 5G NR carrier. In 3GPP, studies are underway to identify and rectify issues related to coexistence between eMTC and NR systems. This paper presents an analysis of such coexistence considering various aspects. The analysis demonstrates that the issues affecting coexistence can generally be handled through implementation. The paper also discusses several mechanisms for achieving improved performance with coexistence.

Ultra-Reliable and Low Latency Communications (URLLC) is an important emerging area for the fifth generation (5G) cellular network. The requirements for URLLC are as stringent as 1-10-5reliability for a 32-byte packet with user plane latency of 1 ms. To achieve these requirements, grant-free transmission with repetitions of data packet has been recently proposed for uplink transmissions. However, the resource overhead and collisions among URLLC user equipments (UEs) become limiting factors to achieving optimal system performance. In this work, a hybrid resource allocation scheme is proposed to optimally allocate dedicated resource units and/or a shared resource pool to a group of UEs. Numerical results based on theoretical analysis show that the target requirements of URLLC can be achieved with up to 70% reduction in resource utilization compared to the conservative transmission scheme.

This paper provides an updated analysis of link-budget and coverage performance for LTE IoT technologies: enhancements for machine type communications (eMTC) and narrowband Internet of Things (NB-IoT). Previous studies have used the 3GPP evaluations assumptions and have demonstrated the coverage capabilities of these technologies when they are independently deployed. Some operators are, however, likely to deploy dual-mode networks - eMTC and NB-IoT - with the intent of supporting different applications in the two systems. With all conditions being equal for the two systems in such a scenario, comparison of the eMTC and NB-IoT technologies then requires that all assumptions are aligned. This paper extends the previous studies with the assumptions aligned for eMTC and NB-IoT systems to provide a fair coverage performance comparison. The study shows that compared to the 3GPP assumption, under the aligned assumptions, both eMTC and NB-IoT can support up to 5dB and 3dB higher uplink coverage, respectively. We further show these link budget improvements yield significantly reduced LTE IoT coverage outage in two simulated scenarios based on real network deployments: a wide area rural case and an urban deep indoor case. The results further demonstrate the potential of these LTE IoT technologies in realistic network deployment conditions.

The Internet of Things (IoT) is expected to reach a massive scale in the next few years and LTE has introduced a feature in Rel-13 called eMTC to support wide-area connectivity for IoT devices. One important trend for IoT is the integration of voice capability into the devices. However, low-cost, low-complexity IoT User Equipment (UE) typically supports only half-duplex communication and low data rates. In this paper, we compare the performance and coverage of low-complexity eMTC UE with legacy non-eMTC UE for delay-sensitive Voice over LTE (VoLTE) service. It is shown that eMTC UE can provide similar coverage to non-eMTC UE using the same delay and block error rate requirements. If the delay budget or quality of service can be relaxed for eMTC, then eMTC can provide slightly better VoLTE coverage. This allows service operators to support voice capability for IoT devices using existing infrastructure footprint.

In 3GPP Rel-13, a narrowband wide-area cellular system, named Narrowband Internet of Things (NB-IoT), has been introduced to provide low-cost, low-power connectivity for the Internet of Things. This system, based on Long Term Evolution (LTE) technology, can be deployed in three operation modes - in-band within LTE carrier, in the guard-band of LTE carrier, and stand-alone. Guard-band deployment allows the operator to support NB-IoT without requiring new spectrum and with minimal impact to LTE. This paper provides an overview and presents a study of NB-IoT deployment in LTE guard band. An analysis of coexistence of NB-IoT with LTE is presented and demonstrates that while there is mutual interference between NB-IoT and LTE on the uplink, the impact on either system is small. A performance analysis of NB-IoT is also presented. The link budget analysis demonstrates how the coverage target can be achieved for the uplink and downlink data channels. Illustrative uplink and downlink link-level simulation results are provided. The analysis in the paper shows that guard-band operation of NB-IoT is feasible and can provide support for massive number of low-throughput IoT devices.

In 3GPP, a narrowband system based on Long Term Evolution (LTE) has been introduced to support the Internet of Things. This system, named Narrowband Internet of Things (NB-IoT), provides low-cost devices, high coverage (20 dB improvement over LTE/GPRS), long device battery life (more than 10 years), and massive capacity. Latency is relaxed although a delay budget of 10 seconds is the target for exception reports. NB-IoT can be deployed in three different operation modes - (1) stand-alone as a dedicated carrier, (2) in-band within the occupied bandwidth of a wideband LTE carrier, and (3) within the guard-band of an existing LTE carrier. In this paper, we undertake a deployment study of NB-IoT using existing LTE infrastructure. We consider the case when only a fraction of the existing LTE cell sites support NB-IoT (so called partial deployment of NB-IoT). In this case, NB-IoT devices cannot attach to the best cell if that cell does not support NB-IoT. As a result, the path loss can be very high. In addition, they also suffer from high interference from non-NB-IoT cells. We examine potential techniques to compensate for the high path-loss and high interference and provide analysis to indicate when partial deployment of NB-IoT is feasible. We also examine interference issues in asynchronous deployments and study performance.

In 3GPP Rel-13, a narrowband system based on Long Term Evolution (LTE) is being introduced to provide wide-area cellular connectivity for the Internet of Things. This system, named Narrowband Internet of Things (NB-IoT), can be deployed in three different operation modes - (1) stand-alone as a dedicated carrier, (2) in-band within the occupied bandwidth of a wideband LTE carrier, and (3) within the guard-band of an existing LTE carrier. The design targets of NB-IoT include low-cost devices, high coverage (20-dB improvement over GPRS), long device battery life (more than 10 years), and massive capacity. Latency is relaxed although a delay budget of 10 seconds is the target for exception reports. This paper discusses the design and performance of the downlink and uplink data channels. Although the design of these channels is based on LTE, there are some differences, particularly in the uplink, with the introduction of subcarrier-level transmission. The similarities have enabled rapid specification, while the enhancements in the design enable the achievement of the stated targets for NB-IoT.

In 3GPP, a narrowband system based on Long Term Evolution (LTE) is being introduced to support the Internet of Things. This system, named Narrowband Internet of Things (NB-IoT), can be deployed in three different operation modes - (1) stand-alone as a dedicated carrier, (2) in-band within the occupied bandwidth of a wideband LTE carrier, and (3) within the guard-band of an existing LTE carrier. In stand-alone operation mode, NB-IoT can occupy one GSM channel (200 kHz) while for in-band and guard-band operation modes, it will use one physical resource block of LTE (180 kHz). The design targets of NB-IoT include low-cost devices, high coverage (20-dB improvement over GPRS), long device battery life (more than 10 years), and massive capacity. Latency is relaxed although a delay budget of 10 seconds is the target for exception reports. The specifications for NB-IoT are expected to be finalized in 2016. In this paper, we describe the targets for NB-IoT and present a preliminary system design. In addition, coverage, capacity, latency, and battery life analysis are also presented.

The Internet of Things will bring about billions of connected devices. In the cellular space, machine type communications using LTE is under consideration by many operators. LTE, however, was designed to provide broadband high-speed data service with very low latency. Machine type communications, on the other hand, have a different set of requirements, namely low-rate, low-overhead, low-power-consumption, and low-cost. To address these requirements and also to minimize impact from machine traffic to human traffic, 3GPP has been working on numerous LTE features such as power saving, overload control, signaling reduction, complexity reduction, and coverage enhancement. This paper will provide an overview of LTE enhancements for machine type communications. The paper will also present LTE capacity analysis for machine traffic as well as the battery life of the devices.

The Internet of Things will bring billions of devices that are inter-connected using cellular networks. LTE cellular systems are being deployed worldwide and will remain in place for the foreseeable future. However, LTE was designed for high data-rate broadband services. Even with M2M features being added in LTE Rel-12, it is not optimized for low data-rate and wide area M2M services such as smart meters, remote sensors, and consumer devices. In this paper, we present a design of a new narrowband M2M system built from existing LTE functionalities for Low Power Wide Area (LPWA) systems. Salient features of this new system include low-cost devices, high coverage, long device battery life, and high capacity. It can be deployed using minimum of one GSM channel and can also share spectrum with existing broadband LTE systems. Cost analysis shows significant reduction compared to LTE UEs. In addition, coverage analysis and capacity results are presented. Finally, coexistence with GSM is analyzed.

In this paper, LTE Rel-10 eICIC, an advanced interference mitigation technique using semi-static coordination and DL CoMP techniques relying on dynamic scheduling are jointly applied in a heterogeneous network comprising of macro and low power nodes. It is shown that these algorithms, when applied jointly and if supported with appropriately designed feedback schemes, can provide complementary benefits and can significantly improve both system capacity and user experience in the network. Using covariance matrix feedback, we observe that the joint application of CoMP and eICIC can provide more than 20% system throughput improvement and more than 40% cell-edge throughput improvement that exceed the gains of either CoMP or eICIC applied individually.

This paper presents the system performance analysis of 3GPP Long-Term Evolution (LTE) and IEEE 802.11 Wireless Local Area Networks (WLAN) in a situation where LTE downlink (DL) has been expanded over to unlicensed frequency band usually used by WLAN. Simple fractional bandwidth sharing mechanism is used to allow both technologies to transmit. The system performance is evaluated by means of fully dynamic network simulations.

The uplink performance of a 4G LTE system, which includes an eNodeB modem and higher layer network elements, is presented in this paper. The physical layer link performance of this pre-commercial prototype, along with comparisons to simulations, is presented. The performance characterization in the lab is done for the shared channel as well as the control channel. Further, we present a demonstration of adaptive modulation and coding capabilities in the LTE uplink.

Soft synchronization of direct sequence spread spectrum (DSSS) signals introduces the capability of despreading the signals with improving estimates of the spreading code. The technique presented here exploits the eigenstructure of a frequency-channelized DSSS signal to estimate the code. The estimate improves steadily with time, resulting in an improving estimate of the message signal. This allows commencement of despreading at an early stage when the code-estimate is still imperfect. This paper presents the development of the algorithm for a single user environment under infinite time-average assumptions. The performance of the technique under finite time-average conditions is demonstrated through computer simulations for single user as well as multi-user environments.

Soft synchronization of direct-sequence spread-spectrum (DS/SS) signals introduces the capability of despreading with a continuously improving estimate of the spreading code. The soft synchronization technique presented and demonstrated in this paper exploits the eigenstructure of a frequency-channelized DS/SS signal to estimate the code. The estimate improves steadily as more data is collected, resulting in an improved estimate of the message signal. This allows commencement of despreading at an early stage when the code-estimate is still imperfect. Under infinite-time average assumptions a perfect code estimate can be obtained when the signal is received in arbitrary levels of white background noise. This paper demonstrates the synchronization performance of the technique through simulations under finite time-average conditions for environments with fading, multipath, and multi-user interference. The soft synchronization capability is demonstrated. Results show that the technique can remove frequency offsets on the received signal that are integer multiples of the code repeat rate, and that its performance is not degraded by multipath.