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Many emerging applications, such as factory automation, electric power distribution, and intelligent transportation systems, require multicast Ultra-Reliable Low-Latency Communications (mURLLC). Since 3GPP Release 17, 5G systems natively support multicast functionality, including multicast Hybrid Automatic Repeat Request and various feedback schemes. Although these features can be promising for mURLLC, the specifications and existing studies fall short in offering guidance on their efficient usage. This paper presents the first comprehensive system-level evaluation of mURLLC, leveraging insights from 3GPP specifications. It points out (i) how mURLLC differs from traditional multicast broadband wireless communications, and (ii) which approaches to provide mURLLC require changing the paradigm compared with the existing solutions. Finally, the paper provides recommendations on how to satisfy strict mURLLC requirements efficiently, i.e., with low channel resource consumption, which increases the capacity of 5G systems for mURLLC. Simulation results show that proper configuration of multicast mechanisms and the corresponding algorithms for mURLLC traffic can reduce resource consumption up to three times compared to the baseline solutions proposed for broadband multicast traffic, which significantly increases the system capacity. [ABSTRACT FROM AUTHOR]

Future 6G networks are envisioned to support very heterogeneous and extreme applications (known as verticals). Some examples are further-enhanced mobile broadband communications, where bitrates could go above one terabit per second, or extremely reliable and low-latency communications, whose end-to-end delay must be below one hundred microseconds. To achieve that ultra-high Quality-of-Service, 6G networks are commonly provided with redundant resources and intelligent management mechanisms to ensure that all devices get the expected performance. But this approach is not feasible or scalable for all verticals. Specifically, in 6G scenarios, mobile devices are expected to have speeds greater than 500 kilometers per hour, and device density will exceed ten million devices per square kilometer. In those verticals, resources cannot be redundant as, because of such a huge number of devices, Quality-of-Service requirements are pushing the effective performance of technologies at physical level. And, on the other hand, high-speed mobility prevents intelligent mechanisms to be useful, as devices move around and evolve faster than the usual convergence time of those intelligent solutions. New technologies are needed to fill this unexplored gap. Therefore, in this paper we propose a choreographed Quality-of-Service management solution, where 6G base stations predict the evolution of verticals at real-time, and run a lightweight distributed optimization algorithm in advance, so they can manage the resource consumption and ensure all devices get the required Quality-of-Service. Prediction mechanism includes mobility models (Markov, Bayesian, etc.) and models for time-variant communication channels. Besides, a traffic prediction solution is also considered to explore the achieved Quality-of-Service in advance. The optimization algorithm calculates an efficient resource distribution according to the predicted future vertical situation, so devices achieve the expected Quality-of-Service according to the proposed traffic models. An experimental validation based on simulation tools is also provided. Results show that the proposed approach reduces up to 12% of the network resource consumption for a given Quality-of-Service. [ABSTRACT FROM AUTHOR]

Summary: This work presents a new miniaturized and broadband metamaterial‐inspired U‐slotted patch antenna (MUPA), aiming to cover the full N78 band in the 5G mobile communications. Two techniques as the mushroom metamaterials and U‐slotted patch are synthetically used in the MUPA. A particular MUPA is designed with low‐cost low‐index substrates with εr = 2.2 and further demonstrated in experiments. It is found that the new antenna has an operating bandwidth of 3.30 to 3.82 GHz (14.6%). The patch length is only 18 mm (0.21λ, λ is the wavelength at the center frequency 3.56 GHz). The radiation characteristics of the MUPA are also studied in experiments. The measured antenna gain is 5.54 dBi whereas the cross‐polarizations are successfully suppressed lower than −16 dB, making the MUPA promising to meet the demands of 5G mobile communications. [ABSTRACT FROM AUTHOR]

In power systems, disturbances between 2 kHz and 150 kHz are called "Supraharmonics" (SH). Although supraharmonics are not a new concept; It has only attracted the attention of researchers, engineers and manufacturers of end-user devices in recent years. Electromagnetic compatibility (EMC) tests, which are required for placing electrical/electronic devices on the market, require the measurement of harmonic currents (50 Hz-2000 Hz) and the measurement of conducted emission values. However, studies and research in the supraharmonic range are quite limited. As systems using semi-conductor technologies with high power and switching in the kHz range such as photovoltaic energy systems, electric vehicle fast charging stations, high speed digital communication systems become widespread, supraharmonics have also begun to be effective in power distribution systems and cause problems. Today, the struggle against high-frequency disturbances caused by the increased use of electrical and electronic devices, switched power electronic devices and power line communication (PLC) devices is even more prominent. Research conducted in recent years have revealed that disturbances between 2 kHz and 150 kHz cause measurement errors in smart meters, audible noise, malfunctions and performance reductions in electrical devices. In this study, sources of supraharmonics, the problems they cause in devices and networks, measurement methods of supraharmonics and related standards, supraharmonic simulation of sample devices and analysis by measurement are given. Measurements and simulation results show that focusing only on EMC requirements in device designs can cause supraharmonics to be neglected, thus negatively affecting the network and other devices. [ABSTRACT FROM AUTHOR]

With the rapid development of 5G networks, the Internet of Things, and new‐generation of AI, there are considerable demands on expanding the capacity of contemporary optical fiber communication systems. One of the most effective avenues involves the extension of the bandwidth of Er‐doped fiber amplifiers, but with limited success. Herein, an Er‐activated hybridized glass fiber are reported, which can help realize broadband telecommunication. The effect of element hybridization on the bandwidth of Er‐activated fiber is clarified and the structure‐optical response relationship is established. A two‐step deposition approach is proposed to overcome the immiscibility barrier of different hybridized elements, and Er‐activated fiber with uniform doping is constructed. The activated fiber presents excellent compatibility with commercial telecommunication systems, providing a small signal gain of >13 dB in the whole L‐band range and a maximum gain of 28 dB. Furthermore, the Er‐activated fiber amplifier device is successfully developed. It exhibits outstanding optical amplification performance with gain >24 dB in the range of 1580–1624 nm, gain fluctuation less than ±0.9 dB, and noise figure <6.5 dB. The results not only provide a new strategy for developing novel active broadband optical fibers, but a valuable solution for new‐generation large‐capacity optical fiber communication systems. [ABSTRACT FROM AUTHOR]

In this work, a microstrip diplexer with 0.004 λg2 (10.1 × 23 mm) overall size is designed, analyzed and fabricated. The proposed diplexer has the smallest size compared to the previously reported microstrip diplexers. The proposed diplexer has a simple and novel structure, wide flat channels and very low S 11 dB . An innovative microstrip structure based on thin coupled lines is used to design of the proposed diplexer. Since in a simple structure the possibility of manufacturing errors reduces, having a simple structure is one of its advantages. Another advantage of this diplexer is two low S 11 dB of 0.17 and 0.14 dB at the lower and upper channels. The operational frequencies of our diplexer are tuned to work at 0.9 GHz and 1.8 GHz for GSM application. It has the privileges of very compact size, simple structure, small S 11 dB , two wide fractional bandwidths (FBWs) of 21 and 24.3% and acceptable S 11 dB and isolation. Due to its two wide FBWs, the presented diplexer is suitable for broadband communication systems. We have fabricated and measured the introduced diplexer to verify the design methodology and simulation results. The obtained results of the diplexer measurement confirm the simulation. [ABSTRACT FROM AUTHOR]

Digital disparities have been a concern among different communities across the U.S. The lack of an integrated approach to evaluate digital connectivity limits our understanding of where and what the differences are to address digital equity. This research utilized broadband internet open data and other government datasets to evaluate the status of digital connectivity across the U.S. where K-12 schools and public libraries are located. This work is funded by the University of North Texas Libraries' Dean's Innovation Grant (DIG) 2021–2022 award. The research data and products are open for others to use and replicate. [ABSTRACT FROM AUTHOR]

We have developed, manufactured, and tested a new feed design for interferometric radio telescopes with "large-N, small-D" designs. Such arrays require low-cost and low-complexity feeds for mass production on reasonable timescales and budgets, and also require those feeds to be compact to minimize obstruction of the dishes, along with having ultra-wide frequency bands of operation for most current and future science goals. The feed presented in this paper modifies the exponentially tapered slot antenna (Vivaldi) and quad-ridged flared horn antenna designs by having an oversized backshort, a novel method of maintaining a small size that is well-suited for deeper dishes (f ∕ D ≤ 0. 2 5). It is made of laser cut aluminum and printed circuit boards, such that it is inexpensive (≲ 7 5 USD per feed in large-scale production) and quick to build; it has a 5:1 frequency ratio, and its size is approximately a third of its longest operating wavelength. We present the science and engineering constraints that went into design decisions, the development and optimization process, and the simulated performance. A version of this feed design was optimized and fabricated for the Canadian Hydrogen Observatory and Radio-transient Detector (CHORD) prototypes. When simulated on CHORD's very deep dishes (f ∕ D = 0. 2 1) and with CHORD's custom first-stage amplifiers, the on-sky system temperature T sys of the complete receiving system from dish to digitizer remains below 30 K over most of the 0.3–1.5 GHz band, and maintains an aperture efficiency η A between 0.4 and 0.6. The entire receiving chain operates at ambient temperature. The feed is designed to slightly under-illuminate the CHORD dishes, in order to minimize coupling between array elements and spillover. [ABSTRACT FROM AUTHOR]

Efficient acoustic communication across the water–air interface has always been expected in the field of ocean exploration. However, the existing research works are mainly concentrated on the narrow-band transmission based on resonance, which greatly limits the transmission capacity and efficiency. Here, we combined air-based and water-based metafluids to realize an exponential gradient impedance matching layer for broadband water–air sound transmission. By cooperatively adjusting the sound velocity and thickness in the matching layers, we modulated the required acoustic parameters of each layer into a reasonable range, which can be conveniently achieved by the proposed metafluids. A matching layer sample was constructed and validated in a water tank. Experimental results show that the proposed matching layer can achieve an average sound energy transmission enhancement above 16.7 dB from 880 to 1760 Hz across the water–air interface. A water–air acoustic communication scene was further experimentally demonstrated through transmitting a multicolor picture from air to water, which shows extremely high communication capacity and accuracy. Our work is promising for more applications based on water-air transmission and opens an avenue to the design and implementation of the extreme impedance matching case. [ABSTRACT FROM AUTHOR]

A compact WLAN band-notched reconfigurable wideband antenna using two mushroom-like electromagnetic band-gap (EBG) structures is proposed in this paper. It is designed based on a dual wideband microstrip feed patch antenna with operating frequency bands of 2.2-3.7 GHz and 4.8-6 GHz. One of the EBG cells is positioned alongside the feed line, while the other EBG cell is laid on the back of the substrate. The patch or ground of the two EBG units are fed with a stronger current through a ground slot and a parasitic stub respectively, and the connections between the EBG structures and the antenna are controlled by loading a PIN diode with two 56 pF DC blocking capacitors. The advantage of this proposed design is that the antenna and the EBG unit can be designed independently. The proposed antenna has an overall size of 35×46×1.6 mm3. When testing the S11 of the antenna, the influence of the bias circuit on the antenna is also considered. The measured results show that the proposed antenna can generate two notched bands of 2.3-2.49 GHz and 5.11-5.51 GHz of WLAN, and the realized gain in the notch bands can be reduced to -2.65 dBi and -4.55 dBi, respectively, demonstrating its anti-interference characteristics, and can be applied in band notch broadband communication systems or anti-interference communication equipments such as unmanned aerial vehicles and radars. [ABSTRACT FROM AUTHOR]

A space-time coding metasurface (STCM) operating in the sub-terahertz band to construct new-architecture wireless communication systems is proposed. Specifically, a programmable STCM is designed with varactor-diode-tuned metasurface elements, enabling precise regulation of harmonic amplitudes and phases by adjusting the time delay and duty cycle of square-wave modulation signal loaded on the varactor diodes. Independent electromagnetic (EM) regulations in the space and time domains are achieved by STCM to realize flexible beam manipulations and information modulations. Based on these features, a sub-terahertz wireless communication link is constructed by employing STCM as a transmitter. Experimental results demonstrate that the STCM supports multiple modulation schemes including frequency-shift keying, phase-shift keying, and quadrature amplitude modulations in a wide frequency band. It is also shown that the STCM is capable of realizing wide-angle beam scanning in the range of ±45°, which offers an opportunity for user tracking during the communication. Thus, the STCM transmitter with high device density and low power consumption can provide low-complexity, low-cost, low-power, and low-heat solutions for building the next-generation wireless communication systems in the sub-terahertz frequency and even terahertz band. [ABSTRACT FROM AUTHOR]

The Non Line of Sight (NLOS) broadband wireless access provided by Worldwide Interoperability for Microwave Access (WiMAX) operating in 2-11 GHz frequency is susceptible to the effects of multipath propagation, diffraction fading, vegetation attenuation, shadowing loss etc. In order to overcome these effects effective fade mitigation techniques, have to be implemented. The Orthogonal Frequency Division Multiplexing-Multiple Input Multiple Output (OFDM-MIMO) is an efficient method that helps in combatting the fading and providing higher SNR to the WiMAX system. According to the IEEE 802.16 specification, for QPSK modulation, a threshold SNR of 6 dB is required for the link to operate. In the present work the use of OFDM-MIMO achieves a SNR above this operating threshold. [ABSTRACT FROM AUTHOR]

In this paper, a comprehensive analysis of traveling wave solutions of two nonlinear Schrödinger type equations are carried out with help of three different integration techniques namely the tanh–coth, Kudryashov and sine–cosine methods. These equations include the (2 + 1)-dimensional perturbed nonlinear Schrödinger's equation and cubic–quintic nonlinear Schrödinger's equation. The obtained travelling wave solutions are in the form of rational function solutions, trigonometric function solutions, exponential function solutions and hyperbolic function solutions. Our proposed results showed that these techniques are reliable to study the nonlinear PDEs in fiber optics. The higher order cubic–quintic nonlinear Schrödinger equation (NLSE) explains the transmission of incredibly low signals and broadband communications that stretch into the spectral region, as well as the doping of optical fiber and the encryption of data in optical fibers. [ABSTRACT FROM AUTHOR]

This paper develops the concept of "lived policy" for the methodological toolkits of critical, qualitative communication policy scholars. Lived policy seeks to understand how public policies are lived by those impacted by them. It is inspired by research in "lived religion" and "lived theology" which connect theological studies with the lived realities of those who practice religion. Lived policy aims to humanize the policymaking process and the critique of public policy by grounding it in the lives of those most impacted by policy decisions. Examples from a larger study on US rural broadband policy are used to illustrate this approach. [ABSTRACT FROM AUTHOR]

The article investigates the lack of broadband accessibility and its impact on employer hiring practices and remote work policies in the U.S. Topics discussed include the U.S. Federal Communications Commission's (FCC) definition of broadband, the digital divide, and employment challenges facing Americans without broadband. Federal and state funding programs designed to improve access to broadband are summarized.

The article explores the intersection between broadband Internet access and its impact on telehealth services and the social determinants of health in the U.S. Topics discussed include legal approaches taken to increase access to broadband Internet and telehealth, barriers to telehealth services, and case studies in access to broadband Internet and its impact on individuals.

The article outlines the work of two law clinics at West Virginia University and their work supporting broadband infrastructure development in West Virginia. Topics discussed include the need for broadband in the state, limitations of the legal landscape for broadband, and the collaboration between the Land Use and Sustainable Development Law Clinic and the Entrepreneurship & Innovation Law Clinic at West Virginia University.

The article examines the inequality of broadband access and use in education in the U.S. Topics discussed include broadband availability for public school students, lack of home broadband for educational purposes including issues of user cost and affordability of home broadband, and the problem of acquiring broadband-related digital literacy skills.

A low profile four‐element multiple‐input multiple‐output (MIMO) array of printed dipole antenna (PDA) backed by second iteration of Giuseppe Peano fractal artificial magnetic conductor (AMC) is introduced for broadband wireless communications. First, a suggested PDA with a pair of microstrip E‐shaped dipoles excited by an E‐shaped microstrip feedline is used to expand the bandwidth in the range of 5.47–6.92 GHz (S11 ≤ −10 dB). Then, the suggested 4 × 4 Giuseppe Peano fractal AMC reflector is loaded into the PDA to exhibit −10 dB measured impedance bandwidth from 4.21 to 7.06 GHz (50.61%) for wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications. The proposed four‐element MIMO array loaded by 6 × 6 AMC reflector with diverse polarizations of elements introduces a low profile wideband structure. The measured results of four elements include the broad bandwidths from 4.3 to 7.05 GHz with enhanced gains (more than 8 dBi) and high efficiencies. The high isolations between the four elements with diverse polarizations are obtained larger than 26.5 dB and they reach 66 dB over the operating bandwidth for MIMO systems. The suggested PDA with AMC compared to the PDA without AMC exhibits a size reduction of 51.33%, enhanced radiation efficiency up to 94%, and excellent impedance matching with uni‐directional radiation patterns. [ABSTRACT FROM AUTHOR]

The LU factorization of very large sparse matrices requires a significant amount of computing resources, including memory and broadband communication. A hybrid MPI + OpenMP + CUDA algorithm named SuperLU3D can efficiently compute the LU factorization with GPU acceleration. However, this algorithm faces difficulties when dealing with very large sparse matrices with limited GPU resources. Factorizing very large matrices involves a vast amount of nonblocking communication between processes, often leading to a break in SuperLU3D calculation due to the overflow of cluster communication buffers. In this paper, we present an improved GPU-accelerated algorithm named SuperLU3D_Alternate for the LU factorization of very large sparse matrices with fewer GPU resources. The basic idea is "divide and conquer", which means dividing a very large matrix into multiple submatrices, performing LU factorization on each submatrix, and then assembling the factorized results of all submatrices into two complete matrices L and U. In detail, according to the number of available GPUs, a very large matrix is first divided into multiple submatrices using the elimination tree. Then, the LU factorization of each submatrix is alternately computed with limited GPU resources, and its intermediate LU factors from GPUs are saved to the host memory or hard disk. Finally, after finishing the LU factorization of all submatrices, these factorized submatrices are assembled into a complete lower triangular matrix L and a complete upper triangular matrix U, respectively. The SuperLU3D_Alternate algorithm is suitable for hybrid CPU/GPU cluster systems, especially for a subset of nodes without GPUs. To accommodate different hardware resources in various clusters, we designed the algorithm to run in the following three cases: sufficient memory for GPU nodes, insufficient memory for GPU nodes, and insufficient memory for the entire cluster. The results from LU factorization test on different matrices in various cases show that the larger the matrix is, the more efficient this algorithm is under the same GPU memory consumption. In our numerical experiments, SuperLU3D_Alternate achieves speeds of up to 8× that of SuperLU3D (CPU only) and 2.5× that of SuperLU3D (CPU + GPU) on the hybrid cluster with six Tesla V100S GPUs. Furthermore, when the matrix is too big to be handled by SuperLU3D, SuperLU3D_Alternate can still utilize the cluster's host memory or hard disk to solve it. By reducing the amount of data exchange to prevent exceeding the buffer's limit of the cluster MPI nonblocking communication, our algorithm enhances the stability of the program. [ABSTRACT FROM AUTHOR]

This paper presents a Uniform Circular Array (UCA) antenna of crossed-dipole that can excite vortex waves in a wide frequency range from 3.5 GHz to 8.4 GHz. In the design process, the theoretical derivation of the influence on the Orbital Angular Momentum (OAM) when the antenna elements are arrayed in Co-directional Antenna Array (CAA) and Rotational Antenna Array (RAA) is given respectively. The fixed mode of the dipoles CAA is achieved by feeding each element with equal amplitude and 90° phase difference produced by the broadband feeding network. Furthermore, the proposed broadband OAM array antenna has been fabricated and measured to verify the predicted properties. The vortex electromagnetic wave with +1 mode could be excited in the bandwidth of 82.35%. Simulated and measured results are in good agreement. The proposed OAM array antenna is simple in design principle, compact in structure and low in profile, making this array antenna an excellent candidate for broadband OAM communication systems. [ABSTRACT FROM AUTHOR]

A wideband quasi-Yagi antenna with symmetrical rectangular slots in the ground plane is studied. The feeding structure of the antenna is simplified, consisting of a microstrip transmission line and a short strip. The driver and director arms are designed as half on both sides of the substrate to improve pattern stability. The antenna's bandwidth is improved by symmetrically adding rectangular slots to the ground. The antenna works between 3 and 7.7 GHz with a gain that varies between 4.7 to 7.4 dBi, a bandwidth of 87.8 % , and an efficiency of more than 90 %. The antenna has a very compact size of 0.42 λ L × 0.42 λ L ( λ L is the wavelength for the lowest operating frequency). The simulation and measurement results are in good agreement. The antenna has highly stable end-fire radiation within its operating frequency and can be used for wideband wireless communication systems. [ABSTRACT FROM AUTHOR]

In order to improve clock synchronization precision of the power distribution field network, a power distribution field network with high‐speed power line broadband carrier communication is designed, and a step‐by‐step precision clock synchronization strategy is developed based on modified timing‐sync protocol for sensor networks. In the strategy, the clock of the central node is calibrated in real‐time as the master clock of the field network by the communication master station through the long‐distance communication network, the time and frequency deviations of the clocks of each node in the network are accurately monitored using the broadcast mechanism and the network time base of the carrier communication, and the clock frequency is gradually amended by re‐calibrating the clock temperature compensation coefficient of the node so that the clock of the node is synchronized step‐by‐step within a clock synchronization cycle. The clock synchronization performances of the field network are tested in the laboratory and jobsite, and test results show that the clock synchronization accuracy of the field network is within ± 0.23 s/24 h, which is 28% higher than that of the power distribution field network based on narrowband power line carrier, and these phenomena of time gap or time repetition are avoided in the clock synchronization process. © 2023 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Today's tactical communications system increasingly relies on the use of broadband waveforms and data rates in the Mbps range. The main requirements of a broadband tactical communications system are wide coverage, high data rate and low power consumption. This paper presents a web application designed for automated radio link budget analysis. The application takes into account various parameters that are critical for establishing a reliable link, including the desired data rate, transmit power, channel bandwidth, signal-to-noise ratio (SNR), bit error rate (BER), modulation scheme, and more. Using this application, it is possible to determine the feasibility of establishing a radio link with the available equipment and achieving specific performance targets before deploying the equipment in the field. This pre-assessment capability significantly increases the efficiency of the radio link deployment process. [ABSTRACT FROM AUTHOR]

The next generation of mobile broadband communication, 5G, is seen as a driver for the industrial Internet of things (IIoT). The expected 5G-increased performance spanning across different indicators, flexibility to tailor the network to the needs of specific use cases, and the inherent security that offers guarantees both in terms of performance and data isolation have triggered the emergence of the concept of public network integrated non-public network (PNI-NPN) 5G networks. These networks might be a flexible alternative for the well-known (albeit mostly proprietary) Ethernet wired connections and protocols commonly used in the industry setting. With that in mind, this paper presents a practical implementation of IIoT over 5G composed of different infrastructure and application components. From the infrastructure perspective, the implementation includes a 5G Internet of things (IoT) end device that collects sensing data from shop floor assets and the surrounding environment and makes these data available over an industrial 5G Network. Application-wise, the implementation includes an intelligent assistant that consumes such data to generate valuable insights that allow for the sustainable operation of assets. These components have been tested and validated in a real shop floor environment at Bosch Termotecnologia (Bosch TT). Results show the potential of 5G as an enhancer of IIoT towards smarter, more sustainable, green, and environmentally friendly factories. [ABSTRACT FROM AUTHOR]

In this paper an ultra-broadband printed antenna is reported for personal communication system applications on a finite ground plane. This proposed miniaturized antenna produces a 10 dB return loss bandwidth of 136.13% with a stable gain of 3.425 dBi. The radiation bandwidth is broadband in nature, while impedance bandwidth is much greater than radiation and gain bandwidth. This antenna supports circular polarization with an axial ratio of less than 3 dB over the measured operating frequency from 3.8 GHz to 20 GHz. An E-U-shaped slot is etched on the elliptical-shaped radiating patch to balance the effect of reactance and to create multiple resonances. Behind the substrate, a rectangular slot with corner truncation is etched on the finite ground plane to enhance the matching profile and the effective resonance. The proposed antenna is suitable for dedicated short-range personal communication system applications while supporting intelligent transport systems, notebooks, smart homes, and wearable devices. [ABSTRACT FROM AUTHOR]

An introduction to articles published in the issue is presented on topics including barriers to extending broadband in the Indigenous North, public participation in Canadian wireless spectrum consultations, and role and methods of merger control in the Canadian telecommunications sector.

Background: Policies for developing broadband in rural and remote regions typically focus on infrastructure funding. This article postulates that funding may be necessary but is often not suffcient to install and operate sustainable broadband services in these areas. Analysis: This article analyzes issues raised in recent Canadian regulatory proceedings concerning broadband deployment and evidence submitted by Indigenous and community broadband providers that serve rural and remote regions in the Canadian North. Conclusions and implications: Several suggestions are provided to improve policies designed to extend reliable and affordable broadband and to facilitate the provision of services by small and Indigenous providers. These include reconsideration of northern jurisdictions to harmonize regulations, a Canadian Radio-television and Telecommunications Commission offce dedicated to Indigenous issues, requirements for Indigenous consultation and training and hiring of residents, and procedures to expedite installation and procurement for Indigenous networks. [ABSTRACT FROM AUTHOR]

In the Chone parish of the province of Manabí, in Ecuador, the National Telecommunications Corporation of Ecuador built a fiber optic network for telecommunications services, replacing the existing copper networks, with very low speed and reliability. This paper presents the planning and execution project of this network, in which a qualitative-quantitative methodology was used, based on current telecommunications project methodologies. The problem was diagnosed through unstructured interviews and field studies. Consequently, the improvement in access to the data networks of entities and households in the area has had a significant impact on the activity of small and medium-sized companies, the management of services for the population and access to distance education offered by the different institutions of the province and the country. [ABSTRACT FROM AUTHOR]

This article describes the design and manufacturing of a dual-band miniaturized printed monopole antenna for WiFi, wireless local area network and worldwide interoperability for microwave access applications. The developed antenna is constituted of a rectangular radiating element with an elliptical slot printed on a FR-4 substrate and powered by CPW feed technique. The overall area of the designed antenna is 20 × 35mm2. The dual-band characteristic is achieved by inserting an elliptical slot in the radiator and rectangular and circular slots in the ground plane. To demonstrate the validity of the simulation outcomes, the proposed antenna was fabricated and tested using E5071C VNA, and the experimental outcomes illustrate that the developed antenna provides dual bands: 2.36–2.45 GHz resonating at 2.4 GHz and 3.2–6.29 GHz resonating at 3.8 and 5.5 GHz. Additionally, the recommended antenna has a high peak gain of 3.38 dB and a peak radiation efficiency of 98% percent. Furthermore, the stated design is a suitable applicant for the broadband communication. [ABSTRACT FROM AUTHOR]

A broadband circularly polarized (CP) printed monopole antenna which fed by coplanar waveguide (CPW) is proposed in the paper. The structure of the novel antenna includes a quarter circular disc radiating monopole, a coupled circular patch, and a bent L-shaped microstrip stub line. The L-shaped microstrip stub line is used to widen the impedance bandwidth and generate a horizontal component of the electromagnetic wave. The adoption of the asymmetric ground coplanar waveguide structure with the single-feed technology and the coupled circular patch, simultaneously achieve wide impedance bandwidth and wide axial ratio (AR) bandwidth. The structure parameters and the surface current of the designed antenna are analysed. The simulation and the measurement are conducted, showing good characterizations of the designed antenna. The 10-dB impedance bandwidth is 7.57 GHz, the fractional bandwidth from 6.05 to 13.62 GHz is 76.9%, the 3-dB axial ratio bandwidth is 3.01 GHz, and the fractional bandwidth from 6.05 to 9.06 GHz is 39.8%. The antenna can generate right/left hand circularly polarized waves in the direction of ± z axis. The designed antenna has wide applications in the fields of Internet of Things (IoT), broadband dual-CP communication systems and polarization diversity systems, wireless personal area network and other advanced communication systems. [ABSTRACT FROM AUTHOR]

In this work, a three-way wide-band in-phase power combiner for ultra-high frequency band (UHF) applications is presented. The proposed power combiner is a modification of the conventional 3-way Wilkinson power combiner. In the proposed power combiner, the floating isolation-resistors are replaced by coaxial baluns and 50-Ω terminations. This configuration is suitable for high-power applications as flange-mount terminations exhibit superior frequency response and heat conduction compared to floating resistors. The coaxial baluns, connected in the star configuration, help for isolation and input-ports matching. The characteristic impedance of coaxial baluns is 50-Ω and is matched to the terminations. This property serves for a broad bandwidth. Even- and odd-mode methods are employed for the analysis and design of the power combiner. To validate the design method and the theoretical results, a three-way power combiner is fabricated, which consists of microstrip, coaxial-cables and some 50-Ω terminations. The combiner provides 20-dB isolation and summing-port return-loss over an octave bandwidth. The operating frequency is between 470 and 860 MHz, which is used for digital video broadcasting–terrestrial (DVB-T). [ABSTRACT FROM AUTHOR]

This article reviews trends in ultra-wideband wavelength-division multiplexing (WDM) transmission techniques for expanding the capacity of optical transmission systems. It also presents NTT's recent research and development results on ultra-wideband WDM transmission for over 100-Tbit/s transmission capacities in a triple-band (S, C, and L bands) WDM configuration. [ABSTRACT FROM AUTHOR]

Private commercialization is making broadband internet accessible through a new frontier: space. Space Exploration Holdings, LLC (SpaceX), is launching a mega-constellation of thousands of small-satellites into low-Earth orbit to provide fixed-satellite service across the globe. In order to do so, SpaceX was required to receive a license from the Federal Communications Commission (FCC). The licensing regime is part of a larger international regulatory framework based on five governing treaties – the Outer Space Treaty, Rescue Agreement, Liability Convention, Registration Convention, and the Moon Treaty. Compliance with these treaties is managed through the International Telecommunications Union (ITU) an agency of the United Nations. In this instance, the FCC's domestic licensing processes ensure compliance by the United States to the ITU's procedures and the treaties. The role of the FCC in maintaining these regulatory operations may, however, introduce risks to consumer privacy. This paper explores the tension between government regulation of information and communication technologies, specifically, small satellite mega-constellations and the right to privacy under the Fourth Amendment of the United States Constitution. [ABSTRACT FROM AUTHOR]

Low‐profile coplanar waveguide antennas are successfully designed considering body‐centric communications requirements. A finite difference in time‐domain‐based programme, which considers dispersion in human tissues and antenna dielectric substrates, is developed for this purpose. Parametric simulations and visualisation helped to acquire a greater understanding of radiation mechanisms. Consequently, two approaches are investigated. In the first approach, the antenna bandwidth is optimised regardless of its size and travelling wave antennas with characteristics suitable for on‐body communications are obtained. In the second approach, restricting the bandwidth to ultrawideband (UWB) frequencies, while minimising the antenna size, leads to low‐profile antennas useful for on‐body as well as for off‐body applications. For each approach, several prototypes are built to validate the proposed designs and check the repeatability of the results. Measured and simulated return loss and radiation patterns are coherent. Based on the consulted bibliography, the smallest low‐cost and low‐profile omnidirectional wearable antenna is made, which covers the entire UWB frequencies with no special coaxial connectors or expensive dielectric substrates. [ABSTRACT FROM AUTHOR]

To disguise man-made communications as natural signals, underwater transceivers have the option to pre-record animal vocalizations, and play them back in a way that carries meaningful information for a trained receiver. This operation, known as biomimicking, has been used to perform covert communications and to emit broadband signals for localization, either by playing pre-recorded animal sounds back into the environment, or by designing artificial waveforms whose spectrum is close to that of bioacoustic sounds.However, organic sound-emitting body structures in animals have very different trans-characteristics with respect to electro-acoustic transducers used in underwater acoustic transceivers. In this paper, we observe the distortion induced by transmitting pre-recorded animal vocalization through a transducer's front-end, and argue that such distortion can be detected via appropriate entropy metrics. We test ten different metrics for this purpose, both via emulated transmission and in two field experiments. Our result indicate which signals and entropy metrics lead to the highest probability of detecting transducer-originated distortions, thus exposing ongoing covert communications. Our research emphasizes the limitations that man-made equipment incurs when reproducing bioacoustic sounds, and prompts for the choice of biomimicking signals that are possibly suboptimal for communications or localization, but help avoid exposing disguised transmissions. [ABSTRACT FROM AUTHOR]

With the development of wireless technology, signals propagating in space are easy to mix, so blind detection of communication signals has become a very practical and challenging problem. In this paper, we propose a blind detection method for broadband signals based on a weighted bi-directional feature pyramid network (BiFPN). The method can quickly perform detection and automatic modulation identification (AMC) on time-domain aliased signals in broadband data. Firstly, the method performs a time-frequency analysis on the received signals and extracts the normalized time-frequency images and the corresponding labels by short-time Fourier transform (STFT). Secondly, we build a target detection model based on YOLOv5 for time-domain mixed signals in broadband data and learn the features of the time-frequency distribution image dataset of broadband signals, which achieves the purpose of training the model. The main improvements of the algorithm are as follows: (1) a weighted bi-directional feature pyramid network is used to achieve a simple and fast multi-scale feature fusion approach to improve the detection probability; (2) the Efficient-Intersection over Union (EIOU) loss function is introduced to achieve high accuracy signal detection in a low Signal-Noise Ratio (SNR) environment. Finally, the time-frequency images are detected by an improved deep network model to complete the blind detection of time-domain mixed signals. The simulation results show that the method can effectively detect the continuous and burst signals in the broadband communication signal data and identify their modulation types. [ABSTRACT FROM AUTHOR]

In this paper, a hybrid continuous inverse class‐F high‐efficiency power amplifier based on phase shift analysis is proposed. A broadband and high‐efficiency microwave power amplifier are designed by adopting load pull, source pull technique, and low‐pass filter matching structure. The measured results show that the drain efficiency ranges from 67.5% to 77.8%, the saturated output power ranges from 40.2 to 42.4 dBm, and the saturated power gain ranges from 10.2 to 12.4 dB in the working frequency band from 2 to 3 GHz. The power amplifier proposed in this paper fits the current broadband microwave communication technology and plays an important role in the transmission of high data flow signals by wireless transmitters. [ABSTRACT FROM AUTHOR]

A new cost-effective mobile fronthaul architecture has been proposed by designing promising analog radio over fiber (ARoF) transmission system compliant with the next generation ultra-dense wavelength division multiplexing passive optical network (UDWDM-PON). It is conceived for standalone 5G/5G+ mobile communication systems driven by broadband multi-input multi-output (MIMO) millimeter wave data signals using two high spectral efficient modulations. The feasibility of the proposed system was firstly proven in terms of spectral tracing supported by theoretical analysis that disclosed good agreement. Furthermore, the obtained simulation results regarding the system performance evaluation after 22 km bidirectional optical fiber links were revealed high reliable characteristics including error-free transmissions at low receiver sensitivities, and measured power penalties less than 1 dB. In addition, the recovered eye diagrams maintained wide openings with high-quality patterns. [ABSTRACT FROM AUTHOR]

In Japan, against the backdrop of the spread of high-definition video-streaming services and network applications such as cloud storage and work applications, the provision of high-speed communication services is gaining pace, and the research and development of optical access networks to support these services is under high expectations. Jun-ichi Kani, a senior distinguished I researcher at NTT Access Network Service Systems Laboratories is playing a leading role in researching and developing new optical access networks for the beyond fifth-generation mobile communication system (5G)/6G era. We interviewed him about the progress of his research activities and his approach to research. [ABSTRACT FROM AUTHOR]

With each passing year, there is a rapid increase in mobile data traffic and also there occurs a demand for bringing a higher data rate to a growing number of users. The next generation networks need to depend on denser infrastructure deployment, reduced inter- and intra-cell interference, [2] simple signal processing, and reduced transmitted power, as well as improved energy and spectral efficiency, to provide seamless connectivity. The mathematical modeling of MIMO systems is discussed, with emphasis on the technology's key features. The latest developments in the MIMO area, such as Multi-user MIMO (MU-MIMO) [1], Massive MIMO, and MIMO OFDM techniques, are then discussed in detail, with an emphasis on their importance in cellular communication systems. Massive MIMO has been regarded as the best approaches to increase spectral and energy efficiency in broadband wireless communication systems. The massive MIMO's channel model must be explored as the first step in evaluating the performance of any communication system. [ABSTRACT FROM AUTHOR]