Mobile Broadband Applications Research Articles

A Dual Port Hybrid Super-wideband MIMO Antenna with Diminished CCL and High BDR for IoT Applications

In this work, a simple hybrid dual port skull-shaped super wideband Multiple Input Multiple Output (MIMO) antenna with improved isolation is designed and analyzed. Each antenna element consists of a skull-shaped radiator along with a rectangular notched chamfered Defective Ground Plane structure (DGS). The proposed antenna’s impedance bandwidth and radiation characteristics are improved by the triple elliptical inclined slot and DGS together. To accomplish the proposed MIMO configuration, the antenna elements are further organized in a linear arrangement. Deteriorated isolation characteristics, which are the key bottleneck for such MIMO schemes, are significantly improved in the proposed design by using a corrugated T-shaped strip decoupling plane. This 2-port MIMO antenna is placed on top of a glass epoxy FR4 substrate and has an overall dimension of 45 × 50 × 0.787 mm3 (0.20λ × 0.19λ × 0.003λ). The proposed MIMO antenna is fabricated and the experimental results are verified with the simulation results. The results indicate that the proposed antenna covers an operational bandwidth of 48.75 GHz (1.25–50 GHz) with a fractional bandwidth of 190.24% and offers an isolation of less than −20 dB throughout the frequency range of operation. The proposed MIMO has an extremely high bandwidth dimension ratio (BDR) of 5092 among the reported antennas. An optimal performance has been achieved with a lower value of Envelope Correlation Coefficient (ECC) ≤ 0.02, high multiplexing efficiency, extremely lower Channel Capacity Loss (CCL) of 0.2, and omnidirectional radiation characteristics. These design metrics show the potential of our antenna to operate for eMBB (Enhanced Mobile Broadband) applications which includes 5G, Augmented reality, and etc.

Concurrent Multiband Direct RF Sampling Receivers

Direct radio frequency (RF) sampling receivers are investigated for use in concurrent multiband reception for mobile broadband (MBB) applications. The recent proliferation of different frequency bands and standards in wireless communications has allowed large increases in mobility and throughput, but the number of receivers in a device is limited by physical space and power consumption. Software Defined Radio (SDR) is increasingly being explored to reduce the number of analog RF components required. This paper examines the use of direct RF digitization, allowing tunable and concurrent reception of multiple bands with a single RF front-end. Full mathematical models of both Nyquist and subband sampling receivers are presented and used to investigate a quadband LTE receiver, which is modeled in Simulink and implemented in a hardware-in-the-loop (HWIL) testbed. Individual bands are simulated to have at worst -95dBm sensitivity for 16-QAM with Nyquist sampling and -83dBm with subband sampling. Desensitization of the receivers due to multiband processing is evaluated theoretically and experimentally, showing a maximum of 3dB degradation, which is within the LTE standard for adjacent band interference.

Design of high-gain wideband substrate integrated waveguide dielectric resonator antenna for D-band applications

The emerging mobile broadband applications and services demand high-performance networks operating at high frequencies. There is need for high gain and wideband antennas for mobile equipment to support high-speed communications in the millimeter (mm) wave and terahertz (THz) frequencies. In this paper, we propose a wideband substrate integrated waveguide (SIW) fed dielectric resonator antenna (DRA) for D-band applications. A rectangular dielectric resonator element is designed to operate in higher order modes. Wideband operation is achieved by merging adjacent resonances of the different modes. We present a systematic and sequential application of impedance matching techniques to merge the passbands of a multi-mode dual-band DRA, to achieve a wideband response. The proposed design operates between 123.97 GHz and 152.13 GHz. This represents a -10 dB bandwidth of 20.39% at the center frequency of 138.05 GHz. The proposed antenna design has stable broadside radiation patterns, exhibiting a high gain of 11.67 dBi, directivity of 13.36 dBi and maximum total efficiency of 79% . The proposed design is suitable for future generation wireless communication in the terahertz band.

A New RF Satellite Link Analyzing and Antenna Effect on Satellite Communication

Satellite communications (SatComs) recently, have admitted as a new technological advances that attracted and raised special investment and ventures. Space communication technology has found many application areas from costly, one-of-a-sort structures, to utilize again of technology on sequential tasks, to the progress of canonical protocols accepted by space agencies of lots of countries. Satellite communication has accepted as one of the important technologies for 5G backhauling, particularly on bandwidth request increased in 5G mobile broad band (eMBB) applications. This paper presents the efficiency of the satellite communication system using 16 QAM digital modulation technique for the X band. This digital modulation method presents high data rate in transmission without raising the bandwidth compared with other digital modulation methods. Applications are realized in Matlab environment and obtained conclusions are discussed such as power spectrum diagrams, constellation schemas and BER ratio for several bands such as 4, 8, 12, 16 GHz.

Hungarian Mechanism based Sectored FFR for Irregular Geometry Multicellular Networks

The growing demands for mobile broadband application services along with the scarcity of the spectrum have triggered the dense utilization of frequency resources in cellular networks. The capacity demands are coped accordingly, however at the detriment of added inter-cell interference (ICI). Fractional Frequency Reuse (FFR) is an effective ICI mitigation approach when adopted in realistic irregular geometry cellular networks. However, in the literature optimized spectrum resources for the individual users are not considered. In this paper Hungarian Mechanism based Sectored Fractional Frequency Reuse (HMS-FFR) scheme is proposed, where the sub-carriers present in the dynamically partitioned spectrum are optimally allocated to each user. Simulation results revealed that the proposed HMS-FFR scheme enhances the system performance in terms of achievable throughput, average sum rate, and achievable throughput with respect to load while considering full traffic.

Effects of Transport Network Slicing on 5G Applications

Network slicing is considered a key technology in enabling the underlying 5G mobile network infrastructure to meet diverse service requirements. In this article, we demonstrate how transport network slicing accommodates the various network service requirements of Massive IoT (MIoT), Critical IoT (CIoT), and Mobile Broadband (MBB) applications. Given that most of the research conducted previously to measure 5G network slicing is done through simulations, we utilized SimTalk, an IoT application traffic emulator, to emulate large amounts of realistic traffic patterns in order to study the effects of transport network slicing on IoT and MBB applications. Furthermore, we developed several MIoT, CIoT, and MBB applications that operate sustainably on several campuses and directed both real and emulated traffic into a Programming Protocol-Independent Packet Processors (P4)-based 5G testbed. We then examined the performance in terms of throughput, packet loss, and latency. Our study indicates that applications with different traffic characteristics need different corresponding Committed Information Rate (CIR) ratios. The CIR ratio is the CIR setting for a P4 meter in physical switch hardware over the aggregated data rate of applications of the same type. A low CIR ratio adversely affects the application’s performance because P4 switches will dispatch application packets to the low-priority queue if the packet arrival rate exceeds the CIR setting for the same type of applications. In our testbed, both exemplar MBB applications required a CIR ratio of 140% to achieve, respectively, a near 100% throughput percentage with a 0.0035% loss rate and an approximate 100% throughput percentage with a 0.0017% loss rate. However, the exemplar CIoT and MIoT applications required a CIR ratio of 120% and 100%, respectively, to reach a 100% throughput percentage without any packet loss. With the proper CIR settings for the P4 meters, the proposed transport network slicing mechanism can enforce the committed rates and fulfill the latency and reliability requirements for 5G MIoT, CIoT, and MBB applications in both TCP and UDP.

Deterministic Channel Aggregation for LTE in Unlicensed Spectrum

We propose Deterministic Channel Aggregation (DCA) for LTE-Unlicensed, where the LTE eNodeB aggregates a predetermined number of channels in the unlicensed spectrum to achieve high data-rate communications. We introduce the MAC layer design, and analyze the collision probability and channel occupation ratio for DCA. Simulation results validate the effectiveness of DCA and our analytical results, when the eNB coexists with multiple WiFi systems under a range of traffic load conditions. DCA is particularly useful for applications that require high bandwidth and enables efficient access control of mobile broadband applications in the LTE-Unlicensed.

Implementation of hybrid fractal metamaterial inspired frequency band reconfigurable multiband antenna for wireless applications

In the present paper authors propose the design and analysis of a hepta band metamaterial inspired octagonal shape antenna using hybrid fractals for wireless applications. Multiband characteristics in the designed antenna is accomplished by introducing of slotted octagonal shape radiating part with hybrid fractal form of Moore curve and Koch curve and two SRR cells. The frequency band reconfigurability is obtained with aid of PIN diodes placed inside the strips connected between Moore curve (fused with centered Koch curve) and feedline. During ON mode of PIN diode antenna operates at seven microwave frequency S-band WiMAX (3.4~3.69 GHz—IEEE 802.16e)/Lower C-band terrestrial fixed and mobile broadband application (4.25~4.76 GHz)/C-band WLAN (5.15~5.35/5.75~5.825 GHz—IEEE 802.11a] (5.4~5.9 GHz)/Lower X-band Earth exploration-satellite service ITU region 2 (7.9~8.4 GHz)/Upper X-band Amateur satellite operating band (10.45~10.50 GHz)/Lower Ku-band Radar communication application (13.25~13.75 GHz)/Middle Ku-band Geostationary satellite service (14.2~14.5 GHz) covering various wireless applications. Proposed design exhibit hexa/hepta band features during OFF/ON mode of PIN diode. An acceptable gain, stable radiation characteristics, and good impedance matching are observed at all the resonant frequencies of the proposed structure.

Implementation of a multiband 5G NR fiber-wireless system using analog radio over fiber technology

This work reports the implementation of a multiband 5G new radio (NR) fiber-wireless (FiWi) system, using analog radio over fiber (A-RoF) technology. Our approach employs a 12.5-km optical fronthaul (FH) for transporting fifth-generation of mobile network (5G) signals up to a remote antenna unit, from which 10-m reach wireless transmissions are performed aiming indoor and outdoor enhanced mobile broadband (eMBB) applications. The aforementioned 5G signals refer to a 5G NR standard at 26 GHz with 400-MHz bandwidth and DSP-based flexible-waveform signal at 3.5 GHz from our transceiver, which can be set as orthogonal frequency division multiplexing (OFDM), filtered-OFDM (F-OFDM) or generalized frequency division multiplexing (GFDM). Additionally, an investigation on the coexistence between 5G NR and Long Term Evolution-Advanced (LTE-A) standards in FiWi systems using the 700 MHz band, aimed for long-range applications, is reported. Experimental results demonstrate 1.65 Gbit/s total wireless throughput in accordance with the 3GPP Release 15 root mean square error vector magnitude (EVMRMS) digital performance requirements.

Compact tri-band T-shaped frequency reconfigurable antenna for cognitive radio applications

This paper presents, new compact tri-band and broadband frequency reconfigurable antenna for cognitive radio applications. The proposed antenna consists of an Ultrawideband sensing antenna and reconfigurable communicating antenna at the same substrate. The sensing antenna is a UWB printed elliptical monopole antenna operates at frequency band from 2.72 to 23.8 GHz which can cover the entire UWB frequency band from 3.1 to 10.6 GHz and cover the broadband up to 20 GHz. The communicating antenna is a T-shaped frequency reconfigurable antenna operates on three bands of 7.925 GHz, 13.16 GHz, and 14.48 GHz under (S11≤-10 dB) with a fractional bandwidth of 14.55%, 6.2%, and 3.3% respectively. The proposed antenna used to operate in two modes one for cognitive radio applications to cover WiMAX, land, Fixed and Mobile satellite, Radar, and broadband applications. The frequency reconfigurability is obtained by using only one RF switch (PIN diode) for changing the operating frequency. The antenna overall dimensions are 42x30x1.6 mm3 printed on an FR-4 epoxy substrate with relative dielectric constant εr=4.3, loss tangent tan (δ)=0.002 and 50Ω microstrip line feed. The maximum obtained simulated gain is 8.5 dB at 13.16 GHz. The S11 is under -20 dB and coupling between the two antennas is less than -15 dB at the resonant frequencies.

DSP-Based Flexible-Waveform and Multi-Application 5G Fiber-Wireless System

This article reports the implementation and experimental performance investigation of a DSP-based flexible-waveform fiber-wireless (FiWi) system for 5G enhanced mobile broadband (eMBB) and new vertical applications. Our radio over fiber-based fronthaul solution uses a wavelength-division-multiplexing passive optical network (WDM-PON) infrastructure, from a commercial Internet service provider, to enable 5G operation over multiple frequency bands, including: a DSP and flexible waveform-based signal at 788 MHz, which can be set as generalized frequency division multiplexing (GFDM) or filtered orthogonal frequency division multiplexing (F-OFDM); 5G new radio (NR) signals at 3.5 or 26 GHz in accordance to 3GPP Release 15; an additional vector 26 GHz signal with bandwidth of up to 800 MHz. The DSP-based functionality provides digital pre-distortion (DPD), besides the real-time waveform generation. Experimental results demonstrate 4.41 Gbit/s total throughput in the air in accordance to the 3GPP requirements, as well as an innovative low-latency M2M application based on PROFINET standard.

QoE-Assured Live Streaming via Satellite Backhaul in 5G Networks

Satellite communication has recently been included as one of the key enabling technologies for 5G backhauling, especially for the delivery of bandwidth-demanding enhanced mobile broadband (eMBB) applications in 5G. In this paper, we present a 5G-oriented network architecture that is based on satellite communications and multi-access edge computing to support eMBB applications, which is investigated in the EU 5GPPP phase-2 satellite and terrestrial network for 5G project. We specifically focus on using the proposed architecture to assure quality-of-experience (QoE) of HTTP-based live streaming users by leveraging satellite links, where the main strategy is to realize transient holding and localization of HTTP-based (e.g., MPEG-DASH or HTTP live streaming) video segments at 5G mobile edge while taking into account the characteristics of satellite backhaul link. For the very first time in the literature, we carried out experiments and systematically evaluated the performance of live 4K video streaming over a 5G core network supported by a live geostationary satellite backhaul, which validates its capability of assuring live streaming users’ QoE under challenging satellite network scenarios.

Deep-Q-Network-Based Multimedia Multi-Service QoS Optimization for Mobile Edge Computing Systems

By offloading storage and computing resources to the edge of networks, mobile edge computing (MEC) is emerged as a promising architecture to reduce the transmission delay and bandwidth waste for mobile multimedia services. This paper focuses on a multi-service scenario in the MEC systems, where the MEC server can provide three multimedia services including live streaming, buffered streaming and low latency enhanced mobile broadband applications for edge users at the same time. In order to satisfy various quality of service (QoS) requirements for different multimedia applications, the 5G QoS model is applied. Notably, the packets from the multimedia applications with the same or similar requirements are mapped into the same QoS flow, and each QoS flow is processed individually. Therefore, how to effectively schedule the limited radio resource for QoS flows is an intractable problem. To address the problem above, a QoS evaluation model is designed, and a QoS maximization problem is formulated. Furthermore, a deep reinforcement learning method, deep-Q-network, is adopted to make decisions to allocate radio resource dynamically. Compared with round-robin and priority-based scheduling algorithms, the simulation results validate that the proposed algorithm outperforms other resource scheduling algorithms for multi-service scenario.

Ultra-Reliable Low Latency Cellular Networks: Use Cases, Challenges and Approaches

Fifth-generation cellular mobile networks are expected to support mission critical URLLC services in addition to enhanced mobile broadband applications. This article first introduces three emerging mission critical applications of URLLC and identifies their requirements on end-to-end latency and reliability. We then investigate the various sources of end-to-end delay of current wireless networks by taking 4G LTE as an example. Then we propose and evaluate several techniques to reduce the end-to-end latency from the perspectives of error control coding, signal processing, and radio resource management. We also briefly discuss other network design approaches with the potential for further latency reduction.

On Enabling 5G Automotive Systems Using Follow Me Edge-Cloud Concept

One of the key targets of the upcoming 5G system is to build a mobile network architecture that supports not only classical mobile broadband applications (i.e., Internet and IMS), but also vertical industry services, such as those of automotive systems, e-health, public safety, and smart grid. Vertical industry is known to have specific needs that cannot be sustained by the current cellular networks. More notably, automotive systems require strict quality of service in terms of ultrashort latency for vehicle-to-infrastructure/network (V2I/N) communications. In this paper, we introduce the Follow Me edge-Cloud (FMeC) concept, leveraging the mobile edge computing (MEC) architecture to sustain requirements of the 5G automotive systems. Assuming that automotive services are deployed on MEC entities, FMeC ensures low-latency access to these services by guaranteeing that vehicles (i.e., as well as user equipment on board vehicles) always connect to nearest automotive service. Besides the FMeC architecture, our contribution in this paper consists in presenting a projection of the FMeC solution on an automated driving use case that integrates automotive and Telco infrastructures, to realize the vision of future 5G automotive systems. We introduce the envisioned software defined networking/OpenFlow-based architecture and our mobility-aware framework based on a set of building blocks that permit achieving the automated driving requirements within 5G network. The evaluation results, obtained conjointly through theoretical analysis and computer simulation, show that our proposed solution outperforms baseline approaches in meeting the automated driving latency requirement and minimizing the incurred global cost.

Applying Big Data, Machine Learning, and SDN/NFV for 5G Early-Stage Traffic Classification and Network QoS Control

Due to the rapid growth of mobile broadband and IoT applications, the early-stage mobile traffic classification becomes more important for traffic engineering to guarantee Quality of Service (QoS), implement resource management, and network security. Therefore, identifying traffic flows based on a few packets during the early state has attracted attention in both academic and industrial fields. However, a powerful and flexible platform to handle millions of traffic flows is still challenging. This study aims to demonstrate how to integrate various state-of-the-art machine learning (ML) algorithms, big data analytics platforms, software-defined networking (SDN), and network functions virtualization (NFV) to build a comprehensive framework for developing future 5G SON applications. This platform successfully collected, stored, analyzed, and identified a huge number of real-time traffic flows at broadband Mobile Lab (BML), National Chiao Tung University (NCTU). Moreover, we also implemented network QoS control to configure priorities per-flow traffic to enable bandwidth guarantees for each application by using SDN. Finally, the performance of the proposed models was evaluated by applying them to a real testbed environment. The powerful computing capacity of the platform was also analyzed.

Optimized WiMAX Profile Configuration for Smart Grid Communications

Worldwide interoperability for microwave access (WiMAX) is one of the wireless communication technologies adopted for communication in smart grids. Due to the inherent differences between smart grid and mobile broadband applications, it is important to adjust planning and deployment of wireless technologies, including WiMAX. To this end, WiMAX is being amended to feature a smart grid system profile known as WiGrid. In this paper, we investigate the optimized configuration of this WiGrid profile, i.e., the choice of frame duration, type-of-service to traffic mapping, scheduling strategies, as well as the system architecture, such that smart grid communication requirements are met. The simulation-based evaluation of WiGrid networks with optimized configurations is facilitated through a newly developed WiGrid module for the network simulator-3 environment. Our results indicate that a priority-based scheduler is an appropriate solution for scheduling time-critical smart grid applications. Furthermore, schedulers should be implemented in such a way that grant sizes smaller than the packet size are avoided, and adjusting the uplink/downlink bandwidth ratio to favor uplink traffic is important to achieve the required latency defined for smart grid applications.

5G Terminals with Multi-Streaming Features for Real-Time Mobile Broadband Applications

5G Terminals with Multi-Streaming Features for Real-Time Mobile Broadband Applications

A Joint Network Coding and Device Association Design for Optimal Local Data Exchange in Fiber-Wireless Access Network

For many emerging mobile broadband services and applications, the source and destination are located in the same local region. Consequently, it is very important to design access networks to facilitate efficient local data exchange. In the past few years, most existing studies focus on either the wired or wireless domains. In this paper, we aim to exploit both the wired and wireless domains. Specifically, we consider a fiber-wireless access network in which a passive optical network (PON), consisting of one optical line terminal and multiple optical network units (ONUs), connects densely deployed base stations. In such a scenario, we propose two novel access schemes to utilize both network coding and device association in the following two cases: each device can be associated with one ONU for uploading and downloading its data packets; and each device can be associated with two different ONUs for uploading and downloading its data packets, which are referred to as, the network coding design and symmetric device association (NCsDA) problem and the network coding design and asymmetric device association (NCaDA) problem, respectively. To understand the potentials of NCsDA, we first formulate a mixed integer nonlinear programming to minimize the weighted number of packet transmissions (WNT), which is related to both the energy consumption and system capacity. We then theoretically analyze the tight upper bounds of the minimal WNT in the PON, which helps us to approximate the NCsDA problem by mixed integer linear programming . We also give theoretical analysis on the NCaDA problem and formulate it as a mixed integer linear programming. Next, we develop efficient algorithms based on linear programming relaxation and give network coding designs to solve the NCsDA problem and the NCaDA problem. To validate our design, we conduct extensive simulations, which demonstrate the impact of important network parameters and the promising potentials of the proposed NCsDA and NCaDA schemes.

An introduction to millimeter-wave mobile broadband systems

Almost all mobile communication systems today use spectrum in the range of 300 MHz-3 GHz. In this article, we reason why the wireless community should start looking at the 3-300 GHz spectrum for mobile broadband applications. We discuss propagation and device technology challenges associated with this band as well as its unique advantages for mobile communication. We introduce a millimeter-wave mobile broadband (MMB) system as a candidate next generation mobile communication system. We demonstrate the feasibility for MMB to achieve gigabit-per-second data rates at a distance up to 1 km in an urban mobile environment. A few key concepts in MMB network architecture such as the MMB base station grid, MMB interBS backhaul link, and a hybrid MMB + 4G system are described. We also discuss beamforming techniques and the frame structure of the MMB air interface.