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Due to the recent expansion in the generations of the communications systems, it is utmost priority to transmit a large amount of data over a wideband frequency spectrum. For this single ultra-wideband (UWB) antennas are the prime choice as compared to the multiple narrow band antennas. A modified pentagonal fractal patch antenna with a modified ground plane covering ultra-wideband has been proposed. The antenna has a compact size of 25 mm × 25 mm × 1.6 mm with peak gain of 2.2 dB. The UWB coverage of the design is achieved by implementing modified co-planar ground, modified fractal geometry and coplanar feed. The proposed design possesses the significant resonance and radiation performance with very compact size on low-cost substrate while covering the whole UWB. Finally, the simulated resonating and radiation characteristics have been validated with the measured characteristics of the fabricated prototype and the results are quite promising. [ABSTRACT FROM AUTHOR]

In this paper, we investigate a learning-based framework that addresses the point-to-point vehicular navigation problem through a robust output regulation approach and test it through Ultra-Wide Band (UWB) communication noise data. Our focus is on the learning-based control policy design and ensuring the stability of the closed-loop system for vehicle dynamics. It is seen that our proposed solution, which relies on reinforcement learning, is data-driven and does not require accurate knowledge of the vehicle motion model. Specifically, we explore learning-based optimal tracking control through state feedback and output feedback, which we categorize as policy iteration and value iteration, respectively. To validate our approach, we incorporated noise samples from a real-world UWB positioning platform into our simulation. Our findings demonstrate that the learning-based method may be effective in both vehicular point-to-point tracking and interference tolerance, even in the presence of real-world noise interference. [ABSTRACT FROM AUTHOR]

A comprehensive design methodology for the realization of ultra‐wideband and highly miniaturized capacitively loaded Marchand baluns (MBs), suitable for integration into balanced antenna systems is presented. A design technique to maximize the fractional bandwidth (FBW) for a given manufacturing process is demonstrated for the first time. Furthermore, a novel MB integration scheme using broadside‐coupled lines and 3D vertically integrated capacitors in a two‐material inkjet printing process is uniquely proposed. The concept has been experimentally validated within the S and C bands. It exhibits a footprint of 0.128 × 0.098 λg2, centre frequency of 4.4 GHz, and FBW of 121%. Its power loss, phase imbalance and amplitude imbalance were measured between 0.8 and 2.2 dB, 3 ± 2°, and 0.4 ± 0.4 dB, respectively. [ABSTRACT FROM AUTHOR]

An integral step in an ultra-wideband localization network installation is determining the positions of the fixed infrastructure nodes, the anchors. This process is time-consuming and usually requires specialized equipment. Additionally, it is difficult to achieve scalability, as any change or addition in the network requires a redetermination of the affected anchors. One can automate this process by utilizing the distance-measuring capabilities of the network infrastructure and employing a distributed position estimation algorithm, such as the consensus subgradient (CSG) algorithm. Yet, the CSG suffers from scalability issues due to high problem dimensionality and data-sharing bottlenecks in practical applications. Consequently, implementation in embedded devices is difficult. In this article, we propose a modification of this algorithm, the neighborhood CSG, which aims toward embedded implementation by local reduction of the problem dimensions without hindering the precision of the original CSG algorithm or its convergence rate. [ABSTRACT FROM AUTHOR]

To mitigate the challenges posed by the confined spatial environment of greenhouses and various obstacles that frequently cause non-line-of-sight (NLOS) communication issues in ultra-wideband (UWB) localization systems, leading to localization difficulties and low accuracy, we propose a real-time greenhouse localization system that recognizes UWB ranging values prior to correction. First, the initial ranging value is obtained through double-sided two-way ranging (DS-TWR). Subsequently, a communication state identifier is designed based on the residual distribution of ranging values across two UWB communication modes. A correction model is then established by analyzing the causes of ranging value deviations. Finally, the NLOS localization deviation is corrected using an improved unscented Kalman filter (IUKF) algorithm. Experimental results in the greenhouse environment demonstrate that the proposed algorithm enhances positioning accuracy by 68% compared to the uncorrected localization method, offering a valuable reference for localization services in greenhouse settings. [ABSTRACT FROM AUTHOR]

In this article, a low loss and compact microstrip ultra-wideband bandpass filter (UWB-BPF) with a narrow-notched band is recommended for suitable applications in ultra-wideband wireless communication systems. The design methodology is presented to develop the microstrip structure of the UWB-BPF pursued by a single notched band (NB) in the passband of the UWB filter. An array of I-shaped defected ground structures and L-shaped defected microstrip structures based lowpass filters is cascaded with a shorted stub based highpass filter to achieve a UWB-BPF response. The two identically folded open stubs are loaded to obtain the narrow NB. The center frequency of the UWB-BPF without the NB is 3.5 GHz, and the stopband is suppressed up to 14.5 GHz. The fractional bandwidth achieved is 160%, with a circuit area of 0.11 ${\rm{\lambda }}_{\rm{g}}^{\rm{2}}$ λ g 2 . Furthermore, the single NB is attained at 5.7 GHz to reject interferences of signal from the 5G network with an attenuation level of 59 dB. The electromagnetic simulated and experimental responses of the designed structures demonstrate a well-matched behavior among them. The NB at 5.7 GHz in the UWB-BPF passband region suppresses the signal interference from the 5G network (5500 MHz), WLAN (5900 MHz), and WiMAX (5800 MHz). [ABSTRACT FROM AUTHOR]

To solve the problem of antenna miniaturization and mutual interference between the communication band of the UWB system and other wireless communication system bands, this paper proposes a UWB monopole antenna which has frequency notch characteristics. By applying two pairs of Split Ring Resonator (SRR) structures on a CPW transmission line, a coupling resonance is generated in a specific frequency band, and the antenna has a dual frequency notch and a wide band notch function. The measured results show that the antenna has good band-notch characteristics in the frequency ranges of 3.3 GHz to 4 GHz and 5.1 GHz to 6.2 GHz, suppressing ultra-wideband interference between WiMAX (3.3 GHz ~ 3.8 GHz) and WLAN (5.15 GHz ~ 5.35 GHz and 5.725 GHz ~ 5.825 GHz) in a wireless communication system. The volume of the antenna is 40 mm × 36 mm × 1 mm, and the measured results are compared with the simulated model results. Besides, the measured and simulated results have a good consistency. [ABSTRACT FROM AUTHOR]

This research focuses on optimizing ultra-wideband (UWB) antennas, which are critical in modern communication systems due to their wide frequency range (3.1–10.6 GHz) and high data transmission capabilities. The study addresses the challenge of optimizing key antenna parameters – such as return loss, peak gain, and radiation efficiency – while also ensuring energy efficiency and network longevity. Traditional optimization methods, such as LEACH-C, often fail to balance these factors, leading to suboptimal performance To solve this problem, the researchers developed the Generalized Position-based Optimization Neural Network (GPON) for UWB antenna optimization. They also evaluated the Position-based Hybrid Neural Network (PAN) method, comparing its performance with existing algorithms including LEACH-C, Firefly Algorithm (FA), HFAPSO, FA-ANN, and HWOABCA. The GPON model reduced return loss to 25.5 dB at 3.5 GHz and improved peak gain to 4.2 dB i, while maintaining 92 % radiation efficiency. In contrast, PAN demonstrated a 15–25 % improvement in residual energy and extended network lifetime by 20 % compared to LEACH-C. These improvements were due to the integration of advanced neural network techniques in GPON and the effective use of positional data in PAN, enabling more precise and adaptive optimization. The ability to balance multiple performance metrics simultaneously – a challenge previous models struggled with – is a key feature. This balance is crucial for UWB antennas in communication systems where both performance and energy efficiency are vital. The findings are especially relevant for practical applications in wireless sensor networks, mobile communications, and radar systems, requiring long-term network reliability and optimal antenna performance [ABSTRACT FROM AUTHOR]

A novel compact two-element MIMO antenna with dual band-notched characteristics for ultra-wideband communication systems is presented and discussed. The proposed antenna consists of two identical and symmetrical radiating elements spaced by 19 mm (0.197 λ0). The main radiating element is composed of a circular and trapezoidal segment, fed by a tapered microstrip line with a common ground plane. In addition, L-shaped and C-shaped slots are inserted in the main radiating element to reject the WLAN band (5.15–5.8 GHz) and the INSAT C-band (6.3–7.3 GHz), respectively. The proposed antenna with dimensions of 22 mm × 34 mm × 1.6 mm has a measurement operating frequency band from 3.1 to 23 GHz (152.4%). Inverted L-shaped stubs and a wide slot are introduced into the ground plane to achieve high isolation between the two ports. The proposed antenna has good MIMO diversity performances; the minimum measured isolation is 22 dB for the entire operating band, the envelope correlation coefficient (ECC) is less than 0.001, the diversity gain (DG) is near 10 and the channel capacity loss (CCL) is less than 0.29 bits/s/Hz, whereas a maximum total active reflection coefficient of − 35 dB is achieved for the whole operating band. [ABSTRACT FROM AUTHOR]

A printed monopole super wideband (SWB) antenna is presented in this paper. It consists of a beveled-shaped radiator and a tapered ground plane. It is investigated that tapering of the radiator and ground plane enhances the impedance matching and results in broad impedance bandwidth. The experimental result depicts that the antenna achieved 164.9% impedance bandwidth from 2.6 to 27.27 GHz. Furthermore, to prevent the interference caused by communication systems within the ultra-wideband (UWB) range, dual-band rejection at Wi-MAX (2.7–4 GHz). and X-band (8.5–12 GHz) are introduced by etching an H-shape and two back-to-back C-shaped notches in the radiator and feedline, respectively. The measured result demonstrates that both slots effectively reject the desired frequency bands with a small shift in the lower frequency edge from 2.41 to 2.6 GHz. In addition, the proposed antenna application is shown in the two elements MIMO system where a bowtie decoupling structure is utilized to improve the isolation. It is found that the presence of a decoupling structure improves the isolation by up to 60%. To characterize the diversity performance, parameters such as Diversity Gain (DG), Envelop Correlation Coefficient (ECC), Channel Capacity Loss (CCL), and Mean Effective Gain (MEG) are calculated and all are found in the acceptable limit. [ABSTRACT FROM AUTHOR]

This paper details the development of an innovative Ultra-Wideband (UWB) Circularly Polarized (CP) Multi-Input Multi-Output (MIMO) antenna. Drawing inspiration from an Electromagnetic Band-Gap Structure, the antenna incorporates Two Via Compact Electromagnetic Band Gap (TVCEBG) cells strategically positioned close to the feedline. The result is a sophisticated triple-band notched planar antenna configuration. To enhance its performance, a slot and a stub are strategically added to the bottom plane, effectively broadening the Axial Ratio Bandwidth (ARBW). This carefully designed setup achieves a wide ARBW while simultaneously rejecting interference at 3.5, 5.5, and 8.2 GHz. Notably, the MIMO antenna demonstrates an axial ratio spanning from 3 to 10.4 GHz, coupled with an impedance bandwidth ranging from 3.1 to 10.6 GHz. Diversity features of the proposed structure are quantified through three key parameters: ECC (Envelope Correlation Coefficient) greater than 0, TARC (Total Active Reflection Coefficient) surpassing 10, and DG (Diversity Gain) exceeding 9.7. These parameters collectively indicate robust diversity characteristics, underscoring the antenna's efficacy in challenging communication scenarios. Practical implementation involves the use of FR4 dielectric substrates, with precise measurements of 42.7 × 55 × 1.6 mm³. This meticulous construction ensures the realization of the proposed structure's theoretical framework, highlighting the antenna's potential applicability in advanced UWB communication systems. [ABSTRACT FROM AUTHOR]

This paper presents a reconfigurable single-filtenna system with three different modes for cognitive radio applications. The filtenna has three independent ports for Ultra Wideband (UWB), WiMAX narrowband mode, and WLAN narrowband mode, respectively. Three PIN diodes (D1, D2, and D3) are attached within the filtenna system and are used to switch between the three different modes in order to achieve frequency reconfiguration. UWB mode for sensing purposes is produced by a monopole antenna and is excited by port P1, which is controlled by D1. The desired frequencies of the narrowband communication modes are achieved by using two narrowband bandpass filters. The 5.2 GHz WLAN narrowband mode is produced by a U-shaped filter. This mode is excited by port P2 and controlled by D2. The second-order rectangular open loop resonator creates the 3.5 GHz WiMAX narrowband mode, which is excited by port P3 and controlled by D3. The simulated (measured) impedance bandwidth covers the range 2.54-12 GHz (2.54-11 GHz) for the UWB mode, with a gain value of 4.89 dB (4.5 dB). The WLAN mode covers the simulated (measured) range 5-5.36 GHz (5-5.26 GHz) with a gain value of 2.24 dB (1.92 dB), and the simulated (measured) bandwidth coverage of the WiMAX mode is 3.33-3.84 GHz (3.15-3.72 GHz) with a gain value of 3 dB (2.65 dB). The mutual coupling values are less than -22 dB for all three modes. [ABSTRACT FROM AUTHOR]

The design and development of a microstrip-based planar ultra-wideband (UWB) bandpass filter (BPF) with single/multiple interference rejection capability is presented. The proposed BPF structure is developed based on the broadside coupled mechanism of microstrip/coplanar waveguide (CPW). The BPF has microstrips and short-circuited CPW capacitively coupled through the substrate. The basic frequency response generated from this geometry covers the necessary UWB spectrum (3.1–10.6 GHz) and possesses appreciable characteristics due to dual transmission zeros at either passband boundary. Multiple resonators are embedded in the basic BPF structure to develop passband notches to circumvent unnecessary interferences. A low-pass filter is later integrated into geometry to extend the upper stopband. The proposed structure is compact and covers an area of only 14 × 11.4 mm2. [ABSTRACT FROM AUTHOR]

This paper presents a method that enables a small car to reach its destination in an indoor environment using ultrawideband technology. For this purpose, we used four anchors and one tag. The tag can move because it is fixed on the car. The anchors and the tag are DWM1001 modules. The configuration of the five DW1001 modules is performed through a smartphone application provided by the manufacturer. The car has been built by us. The controller of the car is a Raspberry Pi microcomputer which controls the driver of the car DC motors by generating PWM signals. In addition, Raspberry Pi communicates with the tag by the UART interface. Thus, our goal was to control the car to reach a certain destination (xd, yd) requested by the user via Wi-Fi. Because the car hosts the tag, it continuously updates its position according to the information received from the four anchors. We implemented two scenarios, considering the initial (x, y) position of the car. In the first scenario, which is simpler, the car moved to its destination either along the x-axis or along the y-axis. In the second scenario, the car moves along one of the axes and then turns 90 degrees to reach its destination. Experimental results that show the precision of the positioning system are presented. [ABSTRACT FROM AUTHOR]

We have studied the interference caused by amplitude and phase distortions induced by rain in ultra-wideband communication systems designed for using amplitude modulation in GeoSurf future satellite constellations. The results concern radio links simulated with the synthetic storm technique at Spino d'Adda (Italy), Madrid (Spain) and Tampa (Florida), which are sites located in different climatic regions. The conclusions are (a) the three sites, although in different climatic zones, are practically indistinguishable; (b) the channel signal-to-noise ratio can be increased or decreased by interference with equal probability. Channel theoretical capacity loss, even in the worst case, is very limited and rain, therefore, does not cause significant linear distortions in ultra-wideband channels at millimeter waves; therefore, these channels could be used at millimeter waves. [ABSTRACT FROM AUTHOR]

The energy efficiency of a communication system using pulse position modulation (PPM) can be increased by reducing the duration of the pulses transmitted over the communication channel to several tens of picoseconds. The employment of an event timer device as a time-to-digital converter (TDC) for demodulation allows the use of PPM with many pulse positions and achieves competitive data transfer speeds. However, along with several-picosecond accuracy of modern event timers, they require a pulse duration of several hundred picoseconds for precise detection. This research is devoted to developing passive techniques for precise pulse expansion from tens of picoseconds to hundreds of picoseconds. We propose two methods: the electrical method, which employs a microstrip low-pass filter (LPF), and the optical method, which uses fiber Bragg grating (FBG). This research offers a detailed analysis of distortion-free pulse expansion requirements, the design of prototypes meeting these requirements, and experimental design verification. Theoretical background, mathematical models, and results of experimental validation of the proposed pulse expansion methods within the laboratory transmitted reference pulse-position modulation (TR-PPM) communication system are provided. [ABSTRACT FROM AUTHOR]

In this work, a quad-port fractal MIMO antenna is configured, simulated, and experimented for ultra-wideband performance with the elimination of three interfering narrow bands. The antenna is assembled on dual 80 × 99.4mm2 FR-4 dielectric substrates wherein the top substrate comprises four 2nd iterative Sierpinski gasket fractal patches and the bottom substrate incorporates a feeding arrangement. The aperture-coupled feeding approach is employed to activate the fractal radiators. The multi-frequency response produced by fractal antenna elements is transformed into a wide working range by modifying apertures (clipped from the ground surface) into spiral-shaped structures and offsetting the feedlines toward the right. The designed array effectively radiates in the 3.07–11 GHz range with 112.7% fractional bandwidth while maintaining minimal inter-element isolation of 16.19 dB. Additionally, each feedline is amalgamated with circular split-ring resonators, U-slots, and rectangular split-ring resonators to eradicate the interference emerging from the C-band (downlink satellite), WLAN, and radio-location band, respectively. Several diversity operation attributes are analyzed and are found to inhere to their admissible standards. The measured performance of the fabricated antenna design (with and without band-stop structures) depicts an agreeable similitude with the simulation results, thus validating the real-world operability of the proposed MIMO antenna in ultra-wideband communication devices. [ABSTRACT FROM AUTHOR]

Electro-optic modulator (EOM) is one of the key devices of high-speed optical fiber communication systems and ultra-wideband microwave photonic systems. Silicon–organic hybrid (SOH) integration platform combines the advantages of silicon photonics and organic materials, providing a high electro-optic effect and compact structure for photonic integrated devices. In this paper, we present an SOH-integrated EOM with comprehensive investigation of EOM structure design, silicon waveguide fabrication with Slot structure, on-chip poling of organic electro-optic material, and characterization of EO modulation response. The SOH-integrated EOM is measured with 3 dB bandwidth of over 50 GHz and half-wave voltage length product of 0.26 V·cm. Furthermore, we demonstrate a microwave photonics phase shifter by using the fabricated SOH-integrated dual parallel Mach–Zehnder modulator. The phase shift range of 410° is completed from 8 GHz to 26 GHz with a power consumption of less than 38 mW. [ABSTRACT FROM AUTHOR]

To study the propagation of an indoor ultrawideband wave, a model with paired reflections from surfaces located opposite each other is proposed. It is shown that, in contrast to open areas, the multipath environment of premises is close to free space in terms of the character of wave attenuation with distance. Due to this, the energy reserve of an ultra-wideband communication line in a room should be higher than outdoors. [ABSTRACT FROM AUTHOR]

This paper presents a novel, simple, and efficient pulse generation technique using BJTs in avalanche mode with mixer effect. The presented design is an improved version of the basic single transistor avalanche pulse generator, and it composes of two identical pulse generators that drive a common 50-Ω load resistor at the output. The output signal exhibits wider bandwidth and narrower pulsewidth, compared to the basic single transistor circuit. The presented pulse generator also provides increased power output without using any power amplifier, and can be used in ground-penetrating radar and ultra-wideband communication systems. [ABSTRACT FROM AUTHOR]

A 5G rotated frame radiator for multiple applications is presented in the following paper. The presented geometry is capable of radiating the large frequency band from 2.91 to 12.17 GHz, which covers the 5G-(I) sub-6 GHz band, X-band communication with high efficiency. The impedance bandwidth of the radiator is 128%, with an electrical size of 0.24 λ × 0.24 λ × 0.15 λ in lambda. The antenna is simulated with an FR4 substrate using CST Simulator. 06-stages evolution process is also investigated by simulations, and corresponding S -parameter results are presented. Antenna's design comprises a patch in a rotated square fractal-like frame fed by a microstrip line. The proposed structure also demonstrates stable radiation patterns across the operating bandwidth. The proposed radiator has a high gain of 3.8 dBi, and an efficiency of 85%, which claimed that UWB range of the designed antenna. Therefore, it is useful for 5G-(I) sub-6 GHz band, X-band applications, including mobile, radar, and satellite microwave communication. [ABSTRACT FROM AUTHOR]

In this communication, a compact flower shaped printed antenna for ultra-wideband communication is proposed. The "flower-shaped" structure is capable of transmitting UWB-band signals. The designed antenna exhibits a return loss ranging from 2.3 to 11 GHz with an 8.7 GHz central frequency and has 130% relative bandwidth. The suggested design includes a patch in the shape of a flower with several slots fed by a microstrip line. Multiple slots have been designed for better resonances at lower modes. The antenna is constructed with an FR4 substrate, and a 50 Ω A-type connector feeds it. The optimum dimensions of the designed antenna are 12 × 16 × 1.6 cubic-millimeters and 0. 092λ ×.12λ × 0.012λ in lambda. The proposed structure also demonstrates stable radiation patterns across the operating bandwidth. The proposed radiator has a high gain of 2.67 dBi, and an efficiency of 85%. It is compact, lightweight, and easy to make. Therefore, it can be used for UWB applications. [ABSTRACT FROM AUTHOR]

This paper proposes a novel 8–18 GHz 90° switched T-type phase shifter (TPS). In contrast to the conventional TPS, the proposed TPS adds a compensation capacitance to greatly enhance the phase shifting capacity. Moreover, the designed structure also integrates a filtering compensation network, which can effectively achieve a flat relative phase shift in a wide band. The proposed 90° TPS is fabricated using 0.15 μm GaAs pHEMT technology. The TPS achieves homogeneous phase shift at 8–18 GHz, with the measured phase error of less than ±1.5°. The insertion loss of the proposed phase shifter is 1.3–2.6 dB, and the chip size is merely 0.53 × 0.86 mm2. Thanks to these excellent performance characteristics, the designed phase shifter is well-suited for ultra-wideband wireless communication and radar systems. [ABSTRACT FROM AUTHOR]

Time-Sensitive Networking (TSN) requires clock synchronization superior to the well-known Network Time Protocol (NTP). The IEEE 802.1AS-2020 used for synchronization in TSN networks is based on the IEEE 1588-2019 standard (also known as Precision Time Protocol, PTP) defines methods and tools to perform sub-microsecond time synchronization over vari- ous communication channels. However, the IEEE 1588 implementation is commonly used with wired communication protocols, although there are use cases that could gain an advantage from a wireless solution. This paper investigates the possibility of PTP clock synchronization through wireless Ultra Wideband (UWB) communication. UWB excels where other wireless technologies are lacking: it provides high accuracy timestamping even if multipath propagation is present. The method is evaluated using commercial, well-accessible cheap hardware, resulting in the order of 10-nanosecond accuracy. The paper also highlights the main error components and requirements for improving wireless PTP synchronization. [ABSTRACT FROM AUTHOR]

This paper produces A simple compact band-notched dielectric resonator antenna used for ultra-wideband (UWB) applications. A rectangular dielectric resonator with rectangular air gab in the middle is used to achieve the optimum bandwidth and optimum gain for the proposed design. To eliminate any possible interference and overlapping, a new technique is presented to make a notch-band for the frequencies that are already used in the UWB such as the WLAN band (5.2-5.6GHz) by etching slots in the feedline. By varying the length of the slots, we can obtain many notch bands at various frequencies. The proposed antenna has a -10 dB impedance bandwidth of 87% from 3.2 GHz to 10.6 GHz. The proposed antenna is simulated by two simulation programs which are basically different to confirm the results; CST Studio suiteTM 2020 simulator based on the Finite-Difference Time-Domain (FDTD) method and HFSS 15 from Ansoft based on the Finite-Element Method (FEM). [ABSTRACT FROM AUTHOR]

A multi-resonating coplanar waveguide (CPW) fed flexible antenna using metamaterial unit cell is designed for various UWB wireless communication systems. The designed unit cell has the total dimension of 14.8mm × 14.8mm × 0.25 mm. The top layer of the cell has a circular ring slot combined with four modified T shaped radiators giving metamaterial characteristics. The unit cell uses perfect boundary conditions along with y axis wave propagation, and it gives wide NRI region covering 2 to 16 GHz of frequency range. The overall gain of proposed CPW fed antenna is increased by using a 3×3 metamaterial array as reflector at the back of antenna. The metamaterial antenna has 2 to 16 GHz of total bandwidth and peak gain of 13.1 dB. Further the measured outcomes are in accordance with the simulated ones. [ABSTRACT FROM AUTHOR]

In this paper, a novel ultra-wideband UWB antenna element with triple-band notches is proposed. The proposed UWB radiator element operates from 2.03 GHz up to 15.04 GHz with triple rejected bands at the WiMAX band (3.28–3.8 GHz), WLAN band (5.05–5.9 GHz), and X-band (7.78–8.51 GHz). In addition, the radiator supports the Bluetooth band (2.4–2.483 GHz). Three different techniques were utilized to obtain the triple-band notches. An alpha-shaped coupled line with a stub-loaded resonator (SLR) band stop filter was inserted along the main feeding line before the radiator to obtain a WiMAX band notch characteristic. Two identical U-shaped slots were etched on the proposed UWB radiator to achieve WLAN band notch characteristics with a very high degree of selectivity. Two identical metallic frames of an octagon-shaped electromagnetic band gap structure (EBG) were placed along the main feeding line to achieve the notch characteristic with X-band satellite communication with high sharpness edges. A novel UWB multiple-input multiple-output (MIMO) radiator is proposed. The proposed UWB-MIMO radiator was fabricated on FR-4 substrate material and measured. The isolation between every two adjacent ports was below −20 dB over the FCC-UWB spectrum and the Bluetooth band for the four MIMO antennas. The envelope correlation coefficient (ECC) between the proposed antennas in MIMO does not exceed 0.05. The diversity gains (DG) for all the radiators are greater than 9.98 dB. [ABSTRACT FROM AUTHOR]

A compact, four-element planar MIMO (Multiple Input, Multiple Output) antenna that operates in an ultra-wideband is presented for diversity application. The orthogonal position of the unit cells replicates the single antenna thrice, thereby decreasing mutual coupling. A UWB MIMO antenna measuring 35 × 35 × 1.6 mm3 is built using a microstrip line (50 Ω impedance) on an FR4 substrate having a thickness of 1.6 mm. The ground plane and radiator of this antenna are adjusted in several ways to bring it within its operating constraints between the frequencies of 3.1 GHz and 10.6 GHz. This technique makes the antenna small and covers the entire ultra-wideband (UWB) frequency range. The NI USRP was used to test the proposed MIMO antenna to determine its real-time performance. Based on the computed results, we conclude that this proposed antenna has outstanding characteristics in terms of performance and is suitable for wireless ultra-wideband indoor communication and diversity utilization with a small size. [ABSTRACT FROM AUTHOR]

With the rapid development of avionics system,a large number of devices and sensors are connected to the in-plane network,which makes the architecture of the in-plane communication network complex and heavy.Wireless communication network can effectively solve many problems,such as complicated wiring,heavy weight and difficult line fault detection.However,wireless network still has certain limitations in real-time and reliability,which is precisely the most concerned problem of airborne interconnection system.In this paper,the existing wired communication network architecture is analyzed,a hybrid communication network architecture of wireless access network and wired backbone network is designed according to its communication characteristics.The candidate wireless communication schemes are evaluated and selected.The fixed time slot of wireless network access is improved to dynamic allocation according to traffic,the mathematical model of dynamic time slot allocation is established,and the TDMA period and the optimal time slot allocation strategy are designed.Finally,a typical airborne network task shows that the strategy can improve the network utilization rate from 36.5% to 41.8% on the premise of ensuring that the system is schedulable,which verifies the effectiveness of the method.

An ultra-wideband (UWB) microstrip bandpass filter is designed and developed on a low-cost FR4 substrate with a dimension of 1.15λ g × 0.38λ g × 0.06λ g. The filter has been designed using ANSYS High Frequency Structure Simulator (HFSS) electromagnetic (EM) software. It is based on a modified stepped impedance square ring resonator excited by quarter wavelength interdigital parallel coupled microstrip lines (PCML) on both ends to obtain UWB performance. Two dumbbell-shaped resonators and rectangular defected ground structures (DGS) are introduced to get a sharper transition from passband to stopband and to minimize the insertion loss respectively. Due to the symmetric structure of the filter, it is analyzed using odd–even mode analysis to find the resonant mode. To validate the EM simulated results, a lumped element equivalent circuit has been proposed. Further, the fabricated filter has been tested using Vector Network Analyzer (VNA) and the passband of the filter is found to be from 2.98 GHz to 9.59 GHz with a fractional bandwidth of 105.2 % and a minimum insertion loss of 0.38 dB. High return loss of −20.4 dB is observed with a group delay variation of 0.36 ns throughout the passband. The proposed filter is suitable for UWB applications like high-speed wireless communication and radar applications. [ABSTRACT FROM AUTHOR]

This article presents a broadband circularly polarized four-port multiple-input–multiple-output (MIMO) antenna with high isolation is presented in this article. The proposed MIMO antenna consists of four octal-shaped monopole antennas with common ground is realized and fabricated on FR-4 (εr = 4.3) substrate with a thickness of 1.6 mm and a size of 140 mm × 140 mm. Measurement results of the presented MIMO antenna show  features of a wide impedance bandwidth (IBW) of 139.39% (2–11.2 GHz) and  a 3-dB axial ratio bandwidth (ARBW) of 91.95% (2.25–6.4 GHz) with simple and economical fabrication. Additionally, the investigated MIMO antenna has high isolation (S21 < -21.8 dB) and a peak gain of 7.88 dBi within the ultra-wideband (UWB) spectrum. It is a promising candidate for UWB MIMO communication systems and 5G wireless communications. [ABSTRACT FROM AUTHOR]

In this manuscript, a compact (size only 9.8mm*9.8mm) Ultra Wide Band (UWB) bandpass filter with a new structure is proposed, which can be used in the UWB wireless communication band authorized by the FCC. The top plane is composed of a pair of back-to-back microstrip lines, and the ground plane structure is based on an asymmetric coplanar waveguide-defect ground structure (ACPW-DGS). UWB is formed by the vertical electromagnetic coupling of the top plane and the ground plane. On this basis, split ring resonator (SRR) and C type resonator (CTR) are utilized to place double notch bands. A novel third order nested C-type resonator (TONCTR) is obtained by performing CTR, which can further optimize the upper stopband while ensuring double notch bands. The filter can be used for filtering within the UWB system, and it can also avoid the amateur radio band (9.2 -10.3GHz) and the X-band satellite link band (9.6-12.3GHz) on UWB communication systems. Finally, the measured results from the fabricated prototype are basically consistent with the simulation results. [ABSTRACT FROM AUTHOR]

For the ultra-wideband chaotic radio pulses an analytical model of an energy detector is designed and closed-form expressions for the optimal threshold and the detection probabilities are derived. The analytical solution is compared with the results of the numerical simulation. The model proves to be well-suited for the chaotic radio pulses with large base B (or processing gain, or the number of freedom degrees), namely, B ≥ 100. Potential applications areas of the proposed model are ultra-wideband communications with chaotic pulse carriers, e.g., ultra-wideband systems of 802.15.x standards, and multi-element chaotic communication systems. [ABSTRACT FROM AUTHOR]

In this letter, a 4.5–7.5 GHz highly integrated transceiver front‐end, incorporating two single‐pole three‐throw (SP3T) transmit/receive (T/R) switches, a low‐noise amplifier (LNA), a power amplifier (PA), and a bypass path for UWB positioning and communication systems applications, is reported. The mode switches among transmitting, receiving, and bypass are achieved by utilizing two control voltages through integrating a 2–4 decoder. Meanwhile, to ensure low‐power dissipation in different modes, the LNA and PA work in different modes (enable or disable) for transmitting and receiving status while both the LNA and PA are disabled for bypass mode. Fabricated by using 0.5‐μm GaAs pHEMT process, the presented FEM achieves 20‐dB gain, and 2.5‐dB typical noise figure for receiving mode, 8‐dB gain, and 16‐dBm OP1dB for transmitting mode, and 1.8 dB insertion loss for bypass mode, with a compact chip area of 1.5 mm × 1.7 mm. To the best of authors' knowledge, the presented circuits are the highest integrated and smallest chip area transceiver front‐end for UWB application among all previously reported UWB‐related RF front‐end chips. [ABSTRACT FROM AUTHOR]

In recent years, the study of microstrip patch antennas has witnessed significant advancements, offering numerous advantages and promising prospects compared with conventional antennas. These antennas are characterized by their lightweight compact size, low cost, low profile, small dimensions, and excellent conformability. Additionally, microstrip patch antennas exhibit various desirable features, such as dual and circular polarization, dual-frequency operation, broad bandwidth, flexible feedline configurations, and beam-scanning omnidirectional patterns. In this paper, a microstrip patch antenna design tailored for the 2.4 GHz frequency band is proposed, showcasing its potential for applications in wireless communication devices. The antenna is engineered to operate across multiple bands, including the wireless device band, Ultra Wide Band (UWB), and X band. It has a truncated rectangle shape with additional stubs, whereas the substrate material employed is FR4. The resulting design achieves resonance at four different frequencies, effectively covering the Microwave Access (WiMAX) band at 2.5 GHz and 4 GHz. Notably, the implementation of Digital Global Systems (DGS) plays a crucial role in reducing the antenna size while simultaneously enhancing its performance. The proposed microstrip patch antenna demonstrates great potential for meeting the increasing demand of modern wireless communication devices. Its multiband operation, compact size, and improved performance, achieved through the integration of DGS, make it a promising candidate for various wireless communication applications. [ABSTRACT FROM AUTHOR]

In this paper, a compact multiple-input multiple-output (MIMO) antenna, with a ground isolation stub for ultra wideband (UWB) communication systems, is presented. The proposed design is based on two symmetrical semi-circular patches, fed by stepped‐impedance microstrip lines, on the top side of the substrate, and a partial ground plane with two symmetrical large rectangular-shaped defected ground structure (DGS) units with a stub in between, and two symmetrical thin rectangular-shaped DGS units, on the bottom side. The two radiating elements are fed using a symmetrical feeding technique for future MIMO antenna systems. The 2-element UWB MIMO antenna with a simple structure and small size of 24 × 35 mm2 is printed on FR4 substrate material. This study has resulted in an impedance bandwidth from 3.3 to 20 GHz which insures that the UWB spectrum is properly covered. In addition to that the elements are well isolated due to the fact that the isolation coefficient is smaller than −20 dB for the whole range of frequencies. The proposed structure exhibits stable omni-directional patterns and nearly bidirectional patterns in both E- and H-planes with an increasing gain across the operation bandwidth. An acceptable agreement between measured and simulated S-parameters is obtained. [ABSTRACT FROM AUTHOR]

This paper proposes the step-by-step design procedure for obtaining independent dual band-notch performance, which provides a valuable method for designing tunable dual band-notched UWB antenna. The proposed antenna consists of the semicircle ring-like radiating patch with an elliptical-shaped slot and double split ring resonators on the top surface of the substrate and defected ground structure (DGS) on the bottom surface of the substrate. The operating frequencies ranged from 1.3 to 11.6 GHz (S11 < − 10 dB). By loading varactor diodes at the gap of the resonators structure and changing the varactor diode's reverse bias voltage(0–30 V), a wider band-notched tuning range from 2.47–4.19 to 4.32–5.96 GHz can be achieved, which covers the whole WiMAX band and WLAN band. The experimental results agree well with the simulated results. The notched gain at notched frequency points is about − 5.3 dBi and − 5 dBi, demonstrating that the narrow-band interference signal could be efficiently suppressed. The security of UWB communication systems can be further enhanced. Meanwhile, the selection of varactor diode and DC bias circuit are fully considered. Hence, the accuracy of the experiment results and antenna operating performance have been improved. Furthermore, the proposed antenna only has an electrical size of 0.26λ*0.19λ at 1.3 GHz. Compared to the related reported antennas, the proposed antenna has achieved a simpler structure, low profile, compact size, tunable dual band-notched characteristics, extensive independent tunable range, and good band-notched performance simultaneously, to the best of our knowledge. The proposed antenna is believed to have a valuable prospect in UWB communication, Wireless Body Area Network, Industry Science Medicine, mobile communication applications, etc. [ABSTRACT FROM AUTHOR]

A CPW‐fed double‐leaf‐shaped ultra‐wideband planar antenna, along with its four‐port MIMO configuration, is presented. The MIMO element is designed through combining the techniques of a modified radiator, coplanar waveguide feeding arrangement, and defected ground structure. The size and operating bandwidth of the MIMO element are 14 × 19 mm2 and 3.73 GHz to 22.01 GHz, respectively. The MIMO element has a peak realized gain of 4.27 dBi and has stable radiation patterns at lower frequencies. In the MIMO configuration, four replicas of this MIMO element are orthogonally arranged to ensure polarization diversity. A rotated plus‐shaped decoupling structure is integrated with the MIMO design for enhancing intra‐element isolation. The proposed MIMO design offers an ultra‐wide bandwidth of 18.28 GHz (3.73 GHz–22.01 GHz), an isolation value of more than 22 dB and an overall footprint of 40 × 40 mm2. ECC < 0.03, CCL < 0.35, MEG < −4 dB, and TARC < −20 dB have been achieved. The MIMO design is fabricated and experimentally tested. The measured data is found to agree well with the simulated data. This antenna will be highly suitable for many ultra‐wideband communication applications in today's world. [ABSTRACT FROM AUTHOR]

In this paper, we propose a compact and highly isolated four-port ultra-wideband MIMO antenna. The antenna elements achieve broadband characteristics by etching a metamaterial structure on the radiating patch and stepping the coplanar waveguide feed. The test results show that the unit antenna can operate from 1.8 GHz to 16.38 GHz with an absolute bandwidth of 14.58 GHz and a relative bandwidth of 160.4% with good radiation properties and gain. After that, a compact four-cell ultra-wideband MIMO antenna is designed by using polarization diversity technology with an overall size of 51.2 mm × 51.2 mm × 1.524 mm. The MIMO antenna can operate from 1 GHz to 17 GHz with an absolute bandwidth of 16 GHz and a relative bandwidth of 177.78%. To reduce the coupling between cells, four angled slits are etched on the common ground to improve the isolation of the MIMO antennas to 27.8 dB. The performance parameters of the proposed MIMO antennas are further validated through simulation analysis and measurements. Moreover, the diversity properties of MIMO antennas are analyzed in detail, demonstrating the applicability of the proposed antennas in UWB communication systems, which can also be used for satellite mobile communications and satellite fixed communication services. [ABSTRACT FROM AUTHOR]

Localization is a keystone for a robot to work within its environment and with other robots. There have been many methods used to solve this problem. This paper deals with the use of beacon-based localization to answer the research question: Can ultra-wideband technology be used to effectively localize a robot with sensor fusion? This paper has developed an innovative solution for creating a sensor fusion platform that uses ultra-wideband communication as a localization method to allow an environment to be perceived and inspected in three dimensions from multiple perspectives simultaneously. A series of contributions have been presented, supported by an in-depth literature review regarding topics in this field of knowledge. The proposed method was then designed, built, and tested successfully in two different environments exceeding its required tolerances. The result of the testing and the ideas formulated throughout the paper were discussed and future work outlined on how to build upon this work in potential academic papers and projects. [ABSTRACT FROM AUTHOR]

The problem of construction of ultra-wideband direct chaotic communication devices in the very high frequency and ultra high frequency ranges of radio waves is considered, the features of this range with respect to the propagation of electromagnetic radiation are discussed, and performance potential is evaluated. Experimental direct chaotic transceivers with a working band of 200–450 MHz, their structure, technical implementation, and characteristics are presented. The results of laboratory and field tests of prototypes are given to demonstrate transmission ranges of up to 1.5 km, which correspond to the calculated characteristics. [ABSTRACT FROM AUTHOR]

This paper presented a compact quad-element flower-shaped (FS) multiple-input multiple-output (MIMO) antenna for ultra-wideband (UWB) communication. The designed antenna exhibits ultra wideband characteristics whose impedance bandwidth (for S11 ≤ − 10 dB) ranges from 3.1 to 11.7 GHz and the inter-port isolation is better than − 14 dB over operating frequency without any decoupling structure. The proposed electrically small (32 × 32 mm2) FS quad-element MIMO antenna is printed on a low-cost FR4 substrate. An FS radiating element is formed by merging four same dimension ellipses at 45° to each other. The top layer of the proposed structure comprises four FS radiating elements, which are positioned orthogonal to each other. The bottom layer consists of asymmetrical ground structures which offer good impedance matching and low mutual coupling between radiating elements at the desired operating frequency band. Besides, the proposed quad-element MIMO antenna with the shared ground is also designed and tested. Its simulated results show satisfactory inter-port isolation of around − 10 dB over frequencies 3.08–11.48 GHz. The antenna provides a low envelope correlation coefficient (ECC < 0.03) and appreciable other diversity parameters. Moreover, the measured 2D radiation patterns confirm the pattern diversity, which will help to mitigate the multipath fading. Also, the simulation study of the MIMO antenna in the actual environment is carried out. Finally, the numerical result of both proposed antennas with the isolated and shared ground is verified experimentally and found suitable for UWB-MIMO applications. [ABSTRACT FROM AUTHOR]

Graph: Figure 17: Measured ECC of UWB-MIMO antenna-1 and UWB-MIMO antenna-2. 4 Conclusions A goblet-shaped quad-notched band antenna was introduced as a prototype antenna. 2 Design of the goblet-shaped quad band-notched UWB antenna 2.1 Antenna structure Firstly, a goblet-shaped UWB antenna with quad NBs is designed as a prototype antenna. Utilizing three CSRR slots and two C-like symmetrical metal stubs, the antenna can minimize interruption from 3.5 GHz WiMAX, 5.3 GHz lower band WLAN, 5.8 GHz upper band WLAN and 8.3 GHz X-band. Keywords: band-notched; CSRR; multiple-input-multiple-output (MIMO); ultra-wideband (UWB) EN band-notched CSRR multiple-input-multiple-output (MIMO) ultra-wideband (UWB) 317 329 13 05/09/22 20220601 NES 220601 1 Introduction In 2002, Federal Communications Commission (FCC) allocated 3.1-10.6 GHz band for ultra-wideband (UWB) applications [[1]]. [Extracted from the article]

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In this paper, we propose a circularly polarized (CP) ultra-wideband (UWB) MIMO antenna. Compared with common linearly polarized (LP) UWB antenna, the proposed antenna can excite circular polarization (CP) mode for WLAN communication and its impedance bandwidth can also fully cover UWB spectrum. It consists of identical circularly polarized antennas. Each unit adopts circular monopole with extended orthogonal rectangle patch to realize broadband and symmetrical rectangular ground with slot in the diagonal of each antenna unit to achieve circular polarization for WLAN band. It has a very compact size and the dimension is 25 χ 51 χ 0.8 mm3. The impedance bandwidth of the proposed antenna is from 3.1 GHz to 13.5 GHz, with average gain of 4 dBi, fully covering UWB bandwidth and enhanced by 38%. At the same time, circular polarization is achieved by embedding two symmetrical rectangular slot structures in the two opposite corners of every antenna unit. The extended orthogonal rectangle patch is introduced to enhance impedance bandwidth and broaden axial ratio (AR) bandwidth. The measured 3 dB axial ratio (AR) bandwidth is 1.8 GHz (4.7-6.5 GHz), fully covering WLAN band. Meanwhile, the slit slot between antenna units and rectangular openings are introduced to achieve high isolation. The proposed antenna keeps ECC (envelope correlation coefficient) below 0.01, which showing good isolation and diversity characteristics. The proposed antenna can simultaneously operate in the UWB spectrum and exhibit circularly polarized (CP) radiation characteristic in WLAN. [ABSTRACT FROM AUTHOR]

In this paper a band notch characteristics reconfigurable UWB leaf shape monopole antenna is reported. The proposed antenna size is 42Ã--32Ã--1.6 mm³ and simulated S11 -10dB impedance bandwidth is from 2.1 to 13.0 GHz. The notch bands are embodied into the designed antenna to suppress Bluetooth and WiFi bands from 2.3-2.7 GHz and 4.6-5.3 GHz. The PIN Diode is loaded to slot on the DGS to achieve notch bands. It has 4.48dB and 1.7dB gain achieved when diode ON and OFF condition. Further, it encompasses a bio-inspired leaf shape patch having high feasibility for deployment in secret and military purposes. [ABSTRACT FROM AUTHOR]

This paper presents ultra-compact ultra-wideband three-section power dividers for 5G sub-6 GHz applications. The n-section power divider design approach is based on the even/odd mode analysis. Hilbert's space-filling curve is used to shrink the dividers' branches' length. Hence, the size is reduced to 89.6 % for the resultant 1-to-2 power divider as compared to the conventional one. Both conventional and ultra-compact 1-to-2 dividers are used to develop 1-to-4 power dividers. The size is reduced to 62 % for the 1-to4 power divider as compared to the conventional one. Both conventional and compact 1-to-4 power dividers are fabricated on an FR4 substrate with a thickness of 1.6 mm and a relative dielectric constant of 4.3. Measured results of the proposed power divider show that an equal power split and good isolation among the output ports are achieved over the specified 5G frequency bands. [ABSTRACT FROM AUTHOR]