Method for traceable calibration of 5G NR measuring receivers

This paper presents a pipelined layered quasi-cyclic low-density parity-check (QC-LDPC) decoder architecture targeting low-complexity, high-throughput, and efficient use of hardware resources compliant with the specifications of 5G new radio (NR) wireless communication standard. First, a combined min-sum (CMS) decoding algorithm, which is a combination of the offset min-sum and the original min-sum algorithm, is proposed. Then, a low-complexity and high-throughput pipelined layered QC-LDPC decoder architecture for enhanced mobile broadband specifications in 5G NR wireless standards based on CMS algorithm with pipeline layered scheduling is presented. Enhanced versions of check node-based processor architectures are proposed to improve the complexity of the LDPC decoders. An efficient minimum-finder for the check node unit architecture that reduces the hardware required for the computation of the first two minima is introduced. Moreover, a low complexity a posteriori information update unit architecture, which only requires one adder array for their operations, is presented. The proposed architecture shows significant improvements in terms of area and throughput compared to other QC-LDPC decoder architectures available in the literature.

Modern cellular wireless communication systems of the fourth (4G) and fifth generation (5G) face a problem of various types of interference or intentional jamming. Consequently, a degradation of the services provided and an incorrect network operation may occur. In this paper, configuration of the networks' physical layer is investigated, with the said investigation preceded by the measurement of parameters of commercial networks operating in two different environments, to assess their vulnerabilities to interference or intentional jamming. Finally, a method for analyzing the radio signal received with the use of 5G New Radio (NR), Long Term Evolution (LTE), and Narrowband Internet of Things (NB-IoT) radio interfaces is proposed, to detect and mitigate the negative impact of unwanted signals. Software-based implementation of the proposed method allows one to detect and mitigate co-channel interference, intentional jamming and maintain compatibility of user equipment (UE) with the 3rd Generation Partnership Project (3GPP) standard, as it does not affect operations performed, for instance, at the time and frequency synchronization or channel parameter estimation phases.

In 5G New Radio (NR) system, beamforming with large antenna array is utilized to compensate the high pathloss. However, the directionality of beam has a significant influence on the performance of co-existence. In this paper, the co-existence of downlink 5G NR homogeneous networks is investigated and analyzed in Urban Macro (UMA). Adjacent channel interference ratio (ACIR), as an important parameter of co-existence analysis, is explored to guarantee the performance of users, especially for the cell-edge users. Capacity loss is used to describe impact of co-existence. The results show the performance of co-existence and give the advice of the appropriate ACIR design. Besides, beam sensitivity and co-existence analysis in alternative array configurations are simulated as a comparison. The co-existence impact of different site deployment for NR systems is studied in the end.

Release-16 of the 5G New Radio (NR), developed by the 3rd Generation Partnership Project (3GPP), includes technology enablers for advanced vehicle-to-everything (V2X) communication services that go far beyond those offered by Long Term Evolution (LTE) systems. In particular, the Release-16 NR cellular interface and the NR sidelink interface are designed to enable platooning, advanced driving such as collision avoidance and cooperative lane change, extended sensors, and remote driving use cases. Compared to the LTE sidelink, the NR sidelink is equipped with a host of new capabilities including physical layer unicast and groupcast, reliable communication using feedback-based retransmissions, operation in millimeter-wave frequencies, advanced resource allocation, and quality of service management. In this article, we summarize the outcome of the related work carried out in 3GPP and discuss how the Release-16 NR capabilities can be used to provide advanced V2X services. We conclude by discussing next steps of the V2X service evolution and the NR sidelink capabilities.

Recent pandemic has affected the telecom industries with the need for connectivity more than before. It has accelerated the research and innovation activities towards 5G and beyond networks. The purpose of the presented work is to provide the urgency of the situation and state the development with the 5G NR (New Radio). 3GPP launched the standardization activity for 5G system in Release 15, 5G New Radio (NR). This paper presents a comprehensive overview of the development of NR, including deployment scenarios, numerologies, frame structure, new waveform and enhanced carrier aggregation (CA). Since coverage and capacity are the key elements of an optimal 5G user experience. Carrier aggregation is visualized as critical for 5G and upcoming networks. It enhances data capacity by aggregating carriers from same/different spectrum bands. Release 10 introduced carrier aggregation and in LTE-Advance, up to five component carriers can be aggregated but commercial solutions use up to three component carriers providing a maximum downlink speed of up to 450Mbps. This paper provides an overview of carrier aggregation, its needs and set of potential solutions and research scope to mitigate the foreseen challenges with CA.

This paper presents a complete design methodology, from behavioral modelling to lab prototyping and validation, of a Distributed Unit (DU) lower physical layer transmission chain, for Fifth Generation (5G) New Radio (NR) wireless communication technology. The case study presented follows a model-driven engineering and prototyping approach, starting with a high-level behavioral model, which is refined and validated in a iterative way, until an hardware implementation is obtained and validated. Fast prototyping is achieved through the adequate combination of languages (Matlab, Simulink and VHDL), simulation and FPGA-based synthesis and debug tools. Simulation-based validation is performed at different stages of the design flow, from behavioral descriptions using floating-point precision, to cycle-accurate models using fixed-point representations. The DU transmission chain supports currently the Frequency Range 1 (FR1) of 5G-NR with a configurable channel bandwidth up to 100 MHz. However, the implemented solution is flexible and modular supporting the configuration of different communication parameters and interfaces for next generation networks. This is achieved through the parametrization of the models and implementation into MPSoC devices to be connected to Software Defined Radio RF frontends, using an automated design flow. Since the complete design occupies less than 5% of the MPSoC resources, the integration of the uplink reception chain and the creation of multiple instances for communication diversity can be done.

Real-time detection and mitigation of jamming attacks in 5G new radio (NR) is an urgent need. Over the past decade, jamming detection has been studied by many researchers using different methods including machine learning. However, nearly all the previous detection methods do not support real-time, which can result in delaying the mitigation and thereby degradation of the overall network performance. Therefore, in this paper, we propose a real-time jamming detection approach based on Hoeffding decision trees in 5G NR. First, we investigate the efficiency of decision trees in detecting jamming and use it as a baseline to validate the performance of the proposed approach. These models have been trained on a dataset built from 5G NR simulation, and the communication link is targeted by a malicious jammer. These models are then evaluated using metrics such as the probability of detection, probability of false alarm, accuracy, and training time. The preliminary results showed that HT can achieve an overall accuracy as high as 82% while traditional decision trees can achieve an accuracy as high as 100%. However, Hoeffding decision trees have the advantages of being trained online while traditional decision trees based models require the complete labeled dataset readily before training which delays the detection process.

The 5G New Radio (NR) standard allows for the utilization of mmWave band to achieve multi-Gbps throughput and low latency. However, radio transceivers are much more sensitive to hardware imperfections such as phase noise and IQ imbalance (IQI) at higher frequencies. Particularly, IQI can severely deteriorate the thorughput of radio links by increasing symbol error rates. This letter proposes a receiver IQI compensation procedure using exclusively the 5G NR reference signals. It is shown that the new method has the capability of outperforming existing procedures while requiring no previous information about the IQI parameters or the channel.

Aiming at the control channel structure and transmission mechanism of 5G New Radio (NR), the preliminary conclusions of corresponding transmission modes and the consideration of pilot density optimization with scene and aggregation level are given through performance simulation under various scenarios. The pilot used to demodulate the control channel and the control channel adopt the same precoding, and the control channel adopt the diversity transmission mode; and then, the control channel disperses on the frequency domain resources, and the dispersion granularity changes with the different degree of aggregation, the dispersion granularity of high aggregation level is large, and the dispersion granularity of low aggregation level is small; lastly, the pilot distribution is adjusted with the change of degree of aggregation, and the dispersion granularity of low aggregation level is low. The pilot density of aggregation grade is dense, and the pilot density of high aggregation grade is sparse. This method can solve the problem that the accurate beam cannot be used for reliable data transmission when the channel information is unknown.

The International Telecommunication Union (ITU) has recently announced the detailed 5G specifications for International Mobile Telecommunications (IMT-2020). A number of candidate Radio Interface Technologies (RITs) were being evaluated by the independent evaluation groups of the ITU. Meanwhile, the roll out of fifth generation (5G) is now going on, and 5G services are offered by more than 160 mobile network operators (MNO). This paper presents the evaluation of the proponent technologies, including the ones specified as <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3^{\text {rd}}$ </tex-math></inline-formula> generation partnership project (3GPP) 5G new radio (NR). The entire 3GPP specifications were examined and evaluated through simulation using Matlab and a custom simulator based on the Go-language. The simulator facilitated the comprehensive evaluation of the 5G NR performance by using the IMT-2020 evaluation framework. Some of the submitted technologies displayed certain discrepancies which were reported to ITU as well as discussed with proponents to improvise the shortcomings. The detailed results and observations are presented in this paper.

Prospective 5G New Radio (NR) systems offer unprecedented capacity boost by the ultradense deployments of small cells operating at mmWave frequencies, with massive available bandwidths. They will facilitate the provisioning of exceptionally demanding mission-critical and resource-hungry applications that are envisaged to utilize the 5G communications infrastructure. In this work, we provide an analytical framework for 5G NR system analysis in terms of queuing theory. We consider a multiservice queuing system with a limited resource with customers that demand varying amount of resource within their service time. Such an approach provides more accurate performance evaluation compared to conventional multiservice models. For the considered model, we propose a method that allows to calculate the stationary probability distribution to the specified accuracy. Our findings are illustrated with a numerical example.

A new adjustable multilevel hybrid (AMH) converter architecture is proposed for the radio frequency (RF) amplifier supply modulators using symbol power tracking. The converter comprises a 4-level switched-capacitor stage and an inductive partial-power-processing stage that allows four output levels to dynamically change depending on symbol power and communication traffic patterns in 5G New Radio (NR). The converter prototype provides a wide range of output voltages from 12V to 50V from a 50V input while delivering the output current up to 1A. It achieves efficiency higher than 85% for a wide range of RF loads and can deliver a maximum RF power of 50W with 98.4% efficiency. When tested with a commercial class-AB PA, a power-added efficiency improvement of 3X is achieved at 11 dB backoff power. The converter prototype supports symbol power tracking for 5G NR with a fast level transition below 50ns that is well within the cyclic prefix time allocated to avoid intersymbol interference.

5G New Radio (NR) is the 3rd Generation Partnership Project (3GPP) radio access technology for the next generation mobile communications network. A major evolution of 5G constitutes the integration of non-terrestrial networks including geostationary and low Earth orbit satellites. The seamless integration of satellites in the terrestrial mobile network requires significant adaptations within the radio access network and the development of new features in the core network to cope with the specific satellite channel characteristics. To date, the 5G control and data plane has been standardized to handle only continuous backhaul communication between the network components. However, a mobile satellite enabled next generation Node B (gNB) located in a vehicle or in a moving aerial platform needs to be able to handle frequent backhaul outages of various duration as well as longer signal delays as opposed to short terrestrial connections via fiber. In this paper, we report the results of an over-the-air (OTA) field trial comprising a mobile edge node connected to the 5G standalone core network components over a geostationary satellite. We analyze Transmission Control Protocol (TCP) acceleration and GPRS Tunneling Protocol (GTP)/TCP/Internet Protocol (IP) header compression features through the GTP. Moreover, the influence of short and long interruptions in the communication between the edge node and the central components on the entire system performance is investigated. The header compression and TCP acceleration modules were implemented on the satellite modems and are now part of the protocol stack of these devices. The results show up to 12% higher data rates for the 5G user equipment (UE), on a 1.5 MHz single carrier return link compared to deactivated TCP acceleration and header compression. We increased the data rate by 20% on the 4.5 MHz DVB-S2X forward link between the UE and 5G core. Moreover, our measurements reveal that even satellite-enabled gNB mobility is possible with the current Release 15 standard. After a short outage of the satellite connection due to shadowing, the UE can successfully re-establish the user plane connection to the core network. Our results will facilitate the full integration of satellite components in 5G through open and standard solutions.

As the need for limitless connectivity surges, non-terrestrial networks (NTN) will play a central role in fifth generation (5G) and beyond communications. The 3rd Gener-ation Partnership Project (3GPP) defines NTN as networks, or segments of networks, using an airborne or space-borne vehicle as a relay node or base station. An NTN-enhanced cellular network supplements a conventional terrestrial cellular network. This article provides an overview of NTN-enhanced cellular networks with a particular focus on satellite-mobile direct communications. First, we review satellite system classifications such as Geostation-ary Orbit (GEO), Medium Earth Orbit (MEO), and Low Earth Orbit (LEO), spectrum usage, and key challenges of satellite communications. We then summarize recent 3GPP activities in NTN. In addition, we describe our recent proof-of-concept system involving a satellite channel emulator and modification of the 5G New Radio (NR) protocol stack to handle the challenge of long round-trip time - demonstrating the feasibility of NTN and the adoption of NTN-enhanced cellular networks in 5G and beyond communications. Finally, we highlight the main open issues and future research challenges of NTN-enhanced cellular networks.

Indonesia is currently constructing the infrastructure and policies necessary for the 5G New Radio (NR) network implementation. Spectrum availability is a necessary condition for the deployment of wireless-based services. Increased allocation of the radio frequency spectrum is one of the techniques to boost network capacity. The most intriguing aspect of Indonesia's low-frequency spectrum situation is that the 700 MHz channel is now reserved for analog television. After the Analog Switch-Off (ASO), there will be a digital dividend in the 700 MHz band, of which 700 MHz can be used for the 5G NR spectrum. Hence, it is necessary to determine the optimal number of gNodeB to support 5G using the 700 MHz frequency. This study aims to determine the required number of gNodeB needed based on coverage planning for implementing 5G NR technology in an urban area in Indonesia, that is, Bandung city, using the 700 MHz frequency band and 30 MHz of bandwidth. In the uplink scenario, the demanded gNodeB is 27, while the downlink is 9. Additionally, a simulation method is done with a network simulator, Forsk Atoll. The simulation results show that the average value of SS-RSRP was −94.15 dB, while the average value of SS-SINR was 13.32 dB, both indicating good performance.