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Optimizing downlink coordinated multipoint (CoMP) performance through advanced scheduling algorithms enhances V2X communication technology, enabling efficient resource allocation, minimizing interference, and maximizing data rates for reliable and synchronized communication between vehicles and infrastructure. In this paper, several scheduling algorithms were compared, including support vector machine (SVM) linear, SVM Radial Basis Function (RBF), SVM Sigmoid, Deep Neural Networks (DNN), Convolutional Neural Networks (CNN), and Graph Convolutional Networks (GCN). The performance metrics used in this comparison included CoMP decision, throughput, and cell edge throughput. The results showed that the out-rated GCN algorithm had the best-triggering composition for 5G radio networks, outperforming the other algorithms in terms of CoMP decision accuracy and overall throughput. In particular, the GCN algorithm demonstrated significant improvements in cell edge throughput, which is critical for ensuring reliable communication in areas with weaker signal strength. The reported results proves that the integration of advanced scheduling algorithms in the downlink CoMP framework enhances the efficiency of V2X communication, enabling optimized resource allocation, interference mitigation, and maximized throughput, thereby improving system efficiency, reducing latency, and ensuring reliable and seamless information exchange for connected vehicles, smart cities, and industrial automation. [ABSTRACT FROM AUTHOR]

The Narrowband Internet of Things (NB-IoT) has been introduced in the 3rd Generation Partnership Project (3GPP) Rel-13 with the aim to provide low-cost, low-power, wide-area cellular connectivity for the Internet of Things. With the exponentially increasing number of connected wireless devices in the order of 100 billion, it has become crucial that researchers develop efficient resource management techniques to meet the 5th Generation (5G) quality of service (QoS) requirements. Recently, several research challenges including the low modulation data rates, energy-expensive channel coding techniques, and the fast-growing number of connected devices have been identified as some of the main issues encountered in the design and deployment of NB-IoT systems. In addition, several techniques have emerged in the literature to resolve some of these challenges of NB-IoT systems. However, the research activities towards the enhancement of the NB-IoT resource management are yet to continue in the next half-decade before, high data rates, energy-efficient, and scalable NB-IoT specifications can be released for the standardisation and commercialisation. Considering the limited number of existing surveys of such technical enhancement approaches in a broader perspective (i.e. energy efficiency, data rate performance and scalability) and also the non-existence, to the best of our knowledge, of a comparative survey, this paper seeks to elaborate, describe and compare the performances of such resources management approaches. Of the multiple NB-IoT resources, the focus of this paper is on the data rate, energy efficiency, and scalability enhancement schemes that have been proposed for the last three years. The contribution of the paper lies in the analysis, synthesis, comparison and summarised alignments of some of the major existing schemes towards identifying challenges faced by the NB-IoT development. Finally, this work seeks to identify research challenges, open questions, and opportunities that could arise from the existing techniques analysed.

In this work, it is proposed that the use of statistical percentage of errors correlated to the Received Signal Strength (RSS) and to both the output power and noise bandwidth, together with the data rate ratio, can give a clear indication of the communication channel quality in the presence of a noise floor. Simulation of a WSN network with variable Data Rate to Noise Band Width ratio (R), different output power (Ptran), and variable Noise Floor Power (Pnoise), showed that each one of these parameters affects error probability distribution and values, which in turn affect channel utilization. The work also proved that these are critical parameters that, if correlated and optimized, can achieve a high utilization of WSN channels. The largest effect realized is related to Pnoise and interference, which, if present at high values, would reduce the probability of exchanging data by 25%. The work also showed that as the ratio R increases, the probability and magnitude of errors increases, which in turn contributes to lower utilization, as depicted in the tables and plots. The 10-nodes WSN is simulated in a uniform topology setting. [ABSTRACT FROM AUTHOR]

Visible light communication (VLC) is a promising technique to provide connectivity to users while providing illumination. To further improve the data rates of VLC systems, multiple sources that transmit multiple simultaneous data streams can be used. This Letter proposes a novel mixture model for VLC systems that make use of multiple sources to provide sufficient flexibility to accurately model the received signal levels for enabling better system designs. The validity of the proposed model is empirically verified through a set of real‐life measurements. [ABSTRACT FROM AUTHOR]

This paper focuses on the design optimization of communication satellites for the constellation in low earth orbit (LEO). The optimization starts with defining an objective function, which is the total mass of satellites, as a function of their orbit altitude, antenna transmit diameter, and nominal data rates. The optimization routine was done in order to minimize the total mass of satellites in order to reduce the total launch mass and the total cost. The use of three different design parameters has led to a genetic algorithm (GA) as an optimization method to find the best value for each design parameter. The results show that the optimization process using a genetic algorithm is successfully applied in solving complex multidisciplinary design problems such as the design of a communication satellite system with acceptable error. [ABSTRACT FROM AUTHOR]

Most of the current research work on the Narrowband Internet of Things (NB-IoT) is focused on enhancing its network coverage. Many of the existing NB-IoT channel coding techniques are based on repeating transmission data and control signals as a way of enhancing the network’s reliability and therefore, enabling long-distance transmissions. Although most of these efforts are made at the expense of reducing the energy consumption of the NB-IoT network, they do not always consider the channel conditions. Therefore, this work proposes a novel NB-IoT Energy-Efficient Adaptive Channel Coding (EEACC) scheme. The EEACC approach is a two-dimensional (2D) approach which not only selects an appropriate channel coding scheme based on the estimated channel conditions (dynamically classified as bad, medium or good from initial based on a periodically assessed BLER performance outcome) but also minimizes the transmission repetition number under a pre-assessed probability of successful transmission (based on the ratio of previous successful transmissions over the total number of transmissions). This results in creating a single mixed gradient based on which a higher or lower Modulating Coding Scheme (MCS) is selected on each transmission. It is aimed at enhancing the overall energy efficiency of the network by dynamically selecting the appropriate Modulation Coding Scheme (MCS) number and efficiently minimizing the transmission repetition number. Link-level simulations are performed under different channel conditions (good, medium, or bad) considerations to assess the performance of the proposed up-link adaptation technique for NB-IoT. The obtained results demonstrate that the proposed technique outperforms the existing Narrowband Link Adaptation (NBLA) as well as the traditional repetition schemes in terms of the achieved energy efficiency as well as network reliability, latency, and scalability.

A 4:1 multiplexer (MUX) circuit in SiGe BiCMOS technology intended to directly drive a plasmonic Mach–Zehnder modulator for transmitter applications is presented. To achieve the highest data rates at a high output voltage swing, a power MUX concept is applied that maps the high‐speed performance of the final clock signal onto the output data. In the clock tree a novel wideband 90° clock phase shifter circuit is utilised for timing adjustment and frequency doubling. Electrical measurements of the chip demonstrate open eye diagrams for non‐return‐to‐zero on‐off‐keying (NRZ‐OOK) signals up to 180 Gbit/s, which is record speed for Si‐based technologies. A differential output voltage swing of 300mVpp was measured that corresponds to an output voltage swing of more than 1Vpp without the bandwidth limit of the measurement equipment. [ABSTRACT FROM AUTHOR]

InAlAs/InGaAs avalanche photodiodes (APD) were simulated using physical device models, then designed and fabricated to detect light in the wavelength range from 1.3 to 1.55 µm. DC characterisation under dark and light conditions were performed at room temperature to measure and investigate the performance of the APD. High‐frequency characterisation was carried out on the device to extract the diode intrinsic and extrinsic parameters. The work reported here focuses on the dark and light physical device simulations (both under DC and AC conditions) which were accomplished using Atlas SILVACO tool. The effect of electron velocity overshoot was considered for accurate bandwidth modelling. All measured data are in excellent agreement with the modelled ones. The internal device gain of the APD is 45 at −23.5 V leading to a ∼220 GHz gain–bandwidth product. This successful APD model can be exploited to further improve the diode structure for higher data rate applications beyond 10 Gb/s. [ABSTRACT FROM AUTHOR]

Miniaturised transceivers are essential in multiband wireless communication systems for higher data rates and low power consumption. Microelectromechanical system (MEMS) resonator filters are actively considered for deployment in transceivers for radio frequency and intermediate frequency (IF) signal filter and oscillator applications. In this study, the authors propose dual frequency capacitive transduced MEMS resonator with two‐port electrical configuration. Clamped–clamped beam resonator was selected to serve as a basic resonant tank for the filter concept validation. Five design strategies low loss structural material, array design, mixed electrical and mechanical coupling scheme, sub‐micro meter transduction gap and large transduction area were explored. With these strategies, the device achieves dual band filter characteristics, narrow pass band, desired bandwidth, low insertion loss and better stop band rejection. Dual frequency response of the proposed resonator is demonstrated at centre frequencies 400 kHz and 2.57 MHz with a narrow pass band of 3 and 20 kHz, respectively. Low insertion loss of 19.8 and 25.6 dB for frequencies centred at 400 kHz and 2.57 MHz, respectively and stop band rejection >35 dB was achieved. The proposed MEMS resonator may be incorporated in the implementation of dual band pass filter for IF signal filter and dual frequency oscillator applications. [ABSTRACT FROM AUTHOR]

The ATLAS Inner Detector will be replaced with a new all-silicon Inner Tracker (ITk) designed for the challenging environment of the High Luminosity LHC (HL-LHC). The ITk layout of the pixel detector was recently successfully optimized to improve tracking performance and object reconstruction. The data rates of the ITk pixel detector have been evaluated to establish that the detector readout system can read out data at the design L0 trigger frequency of 1 MHz. [ABSTRACT FROM AUTHOR]

In this issue’s “Antenna Applications Corner” column, author Rainee N. Simons from NASA’s Glenn Research Center describes link analysis of high-throughput satellite communication systems and its impact on the antenna design and performance for future low Earth orbit (LEO) satellites being planned by NASA. The article discusses two scenarios: 1) the first one employs a high data rate link between LEO and ground via relay satellites in geostationary orbit, and 2) the second one is a high data rate link from LEO directly to ground. Link analysis and data rates are shown for both cases, taking into account effective isotropic radiated power, waveforms, elevation angle, path losses, and the receiving antenna gain/system temperature. This article is useful for system and antenna engineers working on link analysis and hardware trades. [ABSTRACT FROM AUTHOR]

A silicon–germanium BiCMOS E‐band power amplifier (PA) for millimetre‐waves for Gbit/s data rates in fifth‐generation cellular wireless backhaul networks is presented. A 69–78 GHz transmission‐line PA is demonstrated by integrating an electrostatic discharge (ESD) and a power detector together. To save this area, a transmission‐line‐based power coupler is shared by the ESD and the power detector. The ESD achieves an insertion loss of <1.5 dB in the frequency range of 17–100 GHz. The linear‐in‐dB output characteristic of the power detector is achieved by an exponential voltage convertor. The designed PA measured a maximum gain of 18.6 dB with 3 dB bandwidth of 68.9–78.7 GHz. The input return loss is better than −10 dB from 50 to 81 GHz. It delivers 10 dBm saturated output power at 73.4 GHz. Transmission line pulsing (TLP) measurement result shows that the voltage is clamped below 6 V even under 10 A ESD current. [ABSTRACT FROM AUTHOR]

In this letter, the performance of non-orthogonal multiple access (NOMA) is investigated in a cellular downlink scenario with randomly deployed users. The developed analytical results show that NOMA can achieve superior performance in terms of ergodic sum rates; however, the outage performance of NOMA depends critically on the choices of the users' targeted data rates and allocated power. In particular, a wrong choice of the targeted data rates and allocated power can lead to a situation in which the user's outage probability is always one, i.e. the user's targeted quality of service will never be met. [ABSTRACT FROM AUTHOR]

Canonical logic units (CLUs) are basic building blocks for complex all‐optical logic operations, and multicast of CLUs can improve the computing capacity and operating flexibility. The authors thus propose and experimentally demonstrate all‐optical reconfigurable multicast two‐input CLUs (i.e. minterms) at 40 Gb/s by using four‐wave mixing in a single highly non‐linear fibre. Each type of CLUs with clear temporal waveform and wide eye opening is achieved in five parallel channels simultaneously. The extinction ratios are >10.3 dB, while the optical signal‐to‐noise ratios are >21 dB. Based on the demonstrated scheme, a method of realising simultaneous full set of two‐input logic operations is proposed and discussed. The proposed scheme can be extended to higher data rates and transferred to on‐chip platforms. [ABSTRACT FROM AUTHOR]

Most of the current research work on the Narrowband Internet of Things (NB-IoT) is focused on enhancing its network coverage. Many of the existing NB-IoT channel coding techniques are based on repeating transmission data and control signals as a way of enhancing the network's reliability and therefore, enabling long-distance transmissions. Although most of these efforts are made at the expense of reducing the energy consumption of the NB-IoT network, they do not always consider the channel conditions. Therefore, this work proposes a novel NB-IoT Energy-Efficient Adaptive Channel Coding (EEACC) scheme. The EEACC approach is a two-dimensional (2D) approach which not only selects an appropriate channel coding scheme based on the estimated channel conditions (dynamically classified as bad, medium or good from initial based on a periodically assessed BLER performance outcome) but also minimizes the transmission repetition number under a pre-assessed probability of successful transmission (based on the ratio of previous successful transmissions over the total number of transmissions). This results in creating a single mixed gradient based on which a higher or lower Modulating Coding Scheme (MCS) is selected on each transmission. It is aimed at enhancing the overall energy efficiency of the network by dynamically selecting the appropriate Modulation Coding Scheme (MCS) number and efficiently minimizing the transmission repetition number. Link-level simulations are performed under different channel conditions (good, medium, or bad) considerations to assess the performance of the proposed up-link adaptation technique for NB-IoT. The obtained results demonstrate that the proposed technique outperforms the existing Narrowband Link Adaptation (NBLA) as well as the traditional repetition schemes in terms of the achieved energy efficiency as well as network reliability, latency, and scalability. [ABSTRACT FROM AUTHOR]