A Multiband Tree-shaped Microstrip Antenna for Wireless Communication

Conventional microstrip antennas have inherent disadvantages such as low gain, large loss, and poor directivity, this paper taking the antenna gain maximization as the design goal, the presence or absence of square copper patch lattices as the design variables, and introduce a 0.05mm redundant design amount for the square lattice, established A topology optimization model of 24GHz microstrip antenna with metamaterial medium cover. Based on the genetic algorithm's solution strategy, the optimization model is solved, and a new type of metamaterial cover of microstrip antenna without the checkerboard format is obtained. The finite element software is used to simulate the optimized metamaterial cover microstrip antenna, compared with the conventional antenna, the result show antenna gain is improved by 4.24dB and the Half-power beamwidth is shrinking by 48° in the E-plane and 52° in the H-plane, the gain and directivity of the antenna are significantly improved.

Antenna microstrip is one of the lots of antennas used in system telecommunication specifically for microwave frequency. Antenna microstrip own a number of applications as in communication cellular and satellite, GPS, RFID, WiMax, radar, rectenna to use in the medical world. Antenna microstrip has weaknesses such as narrow bandwidth, small gain, and low efficient. In this article an antenna microstrip with hexagonal - rectangular patches 2x4 array will be designed without and with “H” slot. Antenna will be designed and simulated using CST 2019 software. Printing antenna using PCB with substrate made from epoxy fiberglass which has constant dielectric 4.58. Antenna’s parameters that will be measured are return loss, VSWR, gain, radiation pattern, and bandwidth. Measured parameter value then compared between antennas without slots and antennas that use slots with hope antenna microstrip with slots capable of expands bandwidth from antenna without slots. The testing result show that return loss of antenna microstrip without slot is -10.1 dB with bandwidth of 9.45 MHz and return loss of antenna microstrip with a slot is -11.73 dB with bandwidth of 55.59 MHz so can concluded that bandwidth of antenna slots is 46.14 MHz bigger than antenna microstrip without slots.

During natural disasters, communications can be disrupted, which negatively impacts response time of first responders thus diminishing the level of care provided to disaster victims. In the fall of 2014, as part of a larger community-based participatory research study, the Tarleton Area Amateur Radio Club (TAARC) joined the Department of Nursing, Tarleton State University, and provided amateur radio communications during a disaster preparedness simulation. The simulation was conducted to determine the ability of the university to provide rapid response and render quality, acute healthcare to its neighbors during a natural disaster. The primary goals of the TAARC were to assess the ability to quickly establish radio communications, accurately relay messages, and establish rapport and affiliation between each facility commander and the amateur radio operators. It was determined that communication was key to provide quality care, and the inclusion of amateur radio operators in the simulation helped ensure rapid response times and rapid transport of critical victims.

The media as a component of the system of social interaction in a democracy and global communications is a vulnerable area of activity. The study examines modern phenomena in the field of media that are characteristic of the global information space in the context of digitalization and the emergence of artificial intelligence. The main aspects that influence the system of content production and distribution and the principles of interaction in the communication space are identified. The study of variable processes occurring in the communication space is very relevant for Ukraine, which is in a state of unprovoked domestic war with an aggressive neighbor. Today, almost no political or social action is possible without the media component, so it is important to study the transformation processes in this area. An important aspect for specialists in the field of social communications is the terminological content, the dictionary of specialized terms, which is updated with new definitions. The purpose of the study is to provide a comprehensive interdisciplinary view of the role and place of the media, to determine how new technologies of the modern information world of global communications are changing the media and how the media are changing the world; to modernize the conceptual apparatus in the system of media activity in the digital space, taking into account the rapid development of instrumental and technological capabilities. The methodology of the study is dictated by its interdisciplinary discourse, which allowed the use of both general scientific and special research methods. In particular, analysis and synthesis, generalization, hermeneutics, empirical observation and comparison, monitoring of the information space. Results. The modern vocabulary is proposed; the main trends and tendencies in the field of media, Public Relations, advertising and public communications are actualized; the reference points of influence of the emergence of artificial intelligence and the development of media digital space for politics and government are identified; the factors of media activity that become a threat to democratic countries, have a psychological impact on socio-political relations, change and deform reality are indicated; the main challenges for the work of journalists in the global information space are characterized: the quality of content, the decline in trust in traditional media, ets. Practical implications. An interdisciplinary approach to the analysis of the modern media and information sphere gives a new impetus to scientific research in the field of social communications. Value/originality. Generalization and modernization of the vocabulary of social communications, actualization of problems and challenges for the media, socio-political and information space in connection with the development of artificial intelligence technologies with an emphasis on Ukrainian realities is a scientific novelty of the study. The authors offer a comprehensive view of the practices and professions associated with working in a communication space that is constantly evolving and turbulent. For Ukraine, this approach to analyzing the variable components of the digital sphere is unique, as the vulnerability of the socio-political space is exacerbated by the war and information influences from Russia.

This paper outlines the use of amateur radio in teaching a general education writing seminar at Case Western Reserve University, Cleveland, Ohio. The paper first presents a review of amateur radio activities in terms of their cross-curricular potential. This is followed by an overview of the course, which begins by presenting the earliest means of communication over a distance - horns and drums, couriers and smoke signals - and continues into the developments of postal systems and newspapers, optical semaphores, electrical telegraphy and undersea cables, radiotelegraphy, broadcast radio, television, the Internet, and space communication. We examine the issues in each of engineering and content regulation, and of censorship. The censorship issues are presented and discussed including both governmental and voluntary or market-based forms. We conclude with a summary of how writing is integrated into the course, including a discussion of writing assignments and writing-to-learn strategies.

This paper presents the analytical and experimental works on coping with the popularity in wireless communications, especially in satellite communication. Firstly, the “image element” and “arc-shaped orthogonal feeding network" technologies are introduced for the single-band single-polarization antenna array design, the cross polarization is suppressed greatly and the antenna gain is improved. Moreover, an arbitrarily shaped planar array design technique is developed so that the antenna can be well conformal with the limited system space. Secondly, the high efficiency design of large scale antenna array in Ku band is introduced for single-band dual-polarizations antenna designs, including both active and passive array combination techniques. Thirdly, dual-band orthogonal-polarization technique is introduced and applied successfully in dual-band antenna array integrated designs, including linear and circular polarization, and then expanded to the multi-band multi-polarization array designs. Last, a digital beam forming array exhibits highly gain flatness in wide scan angle is presented, also, a novel simple yet accurate array calibration method is developed.

This paper proposes new design of square microstrip antenna with dual feed line for improving bandwidth and axial ratio at work frequency of 2400 MHz. To obtained circular polarization with axial ratio ≤ 3 dB and enhanced bandwidth of antenna, dual feed line is used to improve performance of conventional microstrip antenna. After the simulation process, dual feed line succeed to improved bandwidth of microstrip antenna 131.9 % compared with microstrip antenna with single feed and provide circular polarization with axial ratio 2.44 dB at working frequency of 2400 MHz. compared to the microstrip antenna with a single feed. This research is very usefull for Wi-Fi application in order to improve the level quality of receiver signal.

The aim of this paper is to design an Ultra-Wide Band antenna working in the S band(2-4 GHz), C band(4-8 GHz), X band(8-12 GHz) and the Ku band(12-18 GHz). Hence, a microstrip patch antenna with a star shaped patch, parasitic elements and a broken ground is proposed. The edge length of the proposed antenna is 15 mm each and the structure's height is 1.5 mm. It is operational in the 3.246-13.437 GHz frequency range, with a return loss of 53.466 dB at the resonant frequency of 4.466 GHz. The lower order bandwidth enhancement is first achieved by the introduction of the star patch and furthermore because of the ladder-like structure in the broken ground. The impedance bandwidth achieved is 122.17% and the maximum radiation efficiency is 68.82%. The substrate used is FR-4, and the simulation results are obtained on CST Studio Suite 2020. Stable radiation patterns are observed. The proposed antenna has a wide range of applications like Bluetooth, WiFi, WiMAX, radio and satellite communication.

Amateur radio, often called ham radio, is both a hobby and a service in which participants, called hams, use various types of radio communications equipment to communicate with other radio amateurs for public services, recreation and self-training.Amateur radio operators enjoy personal (and often worldwide) wireless communications with each other and are able to support their communities with emergency and disaster communications if necessary, while increasing their personal knowledge of electronics and radio theory. An estimated three million people throughout the world are regularly involved with amateur radio.Amateur radio operators use various modes of transmission to communicate. Voice transmissions are most common, with some, such as frequency modulation (FM) offering high quality audio, and others, such as single sideband (SSB) offering more reliable communications, often over long distance, when signals are marginal and bandwidth is restricted, without sacrificing audio quality.Over the past century amateur radio operators have contributed to our understanding of radio communications, devised entirely new radio communication technologies, combined pre-existing technologies in innovative new ways, and developed operational procedures that have largely defined the way in which communication by radio is carried out. Amateur radio has played a fundamental role in the development of radio and telecommunications technology, and it continues to do so today.

Low proflle, light weight, easily mounted and broad bandwidth are the key charac- teristics for antennae designed for wireless applications. The microstrip antenna (MSA) suits the features mentioned except for its narrow bandwidth. The bandwidth of the microstrip antenna usually ranges from less than 1% to several percent. This paper experimentally investigates an alternative approach in enhancing the bandwidth of the microstrip antenna for the Wireless Lo- cal Area Network (WLAN) application operating at a frequency of 2.45GHz. The bandwidth enhancement technique which is studied is the Identical Dual Patch Microstrip Antenna with Air-Gap (IDMA). A bandwidth enhancement of more than 11% was achieved. Wireless applications have undergone rapid development in recent years. One particular wireless application that has experienced this trend is the Wireless Local Area Network (WLAN). The wireless application that is selected to be studied is the 2.4GHz to 2.5GHz frequency band which is based on the 802.11b WLAN standard. This frequency band is very popular due to its low cost. WLAN antenna requires being low proflle, light weight and broad bandwidth. The microstrip antenna suits the features very well except for its narrow bandwidth. The WLAN antenna should have a minimum bandwidth of 100MHz to fully utilize the WLAN band based on the 802.11b standard. The conventional microstrip antenna could not fulflll this requirement as its bandwidth usually ranges from less than 1% to several percent (1). Although the required operating frequency range is from 2.4GHz to 2.5GHz, at least double the bandwidth is required to avoid expensive tuning operations and to cause uncritical manufacturing. Therefore, there is a need to enhance the bandwidth of the microstrip antenna for WLAN applications. This paper investigates a technique which can enhance the bandwidth of the microstrip antenna without increasing the lateral size and the complexity of the microstrip antenna too much. The Identical Dual Patch Microstrip Antenna with Air-Gap (IDMA) bandwidth enhancement technique takes the advantage of using the air gap to lower the efiective permittivity and increase the total thickness of the microstrip antenna which is essential for bandwidth enhancement. This bandwidth enhanced microstrip antenna can be deployed for the WLAN application operating at a frequency of 2.45GHz. 2. SIMULATED AND MEASURED RESULTS OF THE SINGLE-LAYER MICROSTRIP ANTENNA

This study presents an examination of the design and evaluation process of an elliptical dipole antenna operating at the design frequency of 5 GHz. Initially based on conventional dipole antenna principles, the antenna's design is iteratively refined through bandwidth enhancement techniques, resulting in the emergence of ultra-wideband characteristics. Notably, the modified antenna design features a distinctive notch band spanning from 4.21 to 10.06 GHz, positioning it as a versatile solution suitable for applications across the mid-band of 5G, as well as the full Ku and partial Ka bands, encompassing frequencies from 27 GHz to 31 GHz. Furthermore, this study investigates the impact of varying dielectric constants on antenna parameters, shedding light on a critical aspect often overlooked in conventional dipole antenna calculations. Through systematic analysis, it is revealed that a dielectric constant of 4.3, aligned with the commonly used low-cost epoxy-based FR-4 material, yields optimal performance. While higher dielectric constants broaden the antenna's characteristics, lower values are found to enhance communication efficiency, thus offering potential benefits in terms of power consumption and cost savings. The detailed examination and findings presented in this study enrich the understanding of antenna design principles and provide valuable guidance for future research and practical applications in the field of wireless communication and antenna engineering.

This paper reviews the expected wide and profound impact of nanotechnology for future wireless devices and communication technologies. This article points out the possibilities of overcoming the same problem set from a device perspective by taking advantage of the merits of nanotechnologies. At the same time, open research issues and challenges are identified to spark new interests and developments in this field. Devices that use wireless communication range from RFID tags to TV receivers, and satellites to mobile phones. The availability of internet access from tablets and mobile phones is growing at an exponential rate, causing increasing demands on the performance of wireless networks and mobile devices. Some passive components necessary in wireless devices, such as inductors and capacitors, cannot be minimized as quickly as transistors and integrated circuits. This imbalance makes it likely that the performance requirements of mobile handsets will exceed the capabilities of current RF technologies within the next 10 to 15 years. As well as the global growth in mobile internet access via tablets and smartphones, wireless sensors, health monitoring systems and other devices dependent on wireless communication are becoming more and more prevalent. Developing more compact, more efficient, and less expensive wireless communication devices will have significant impact on these areas and enable new solutions for healthcare services, logistics and environmental monitoring. The devices that use wireless communication ranges from RFID tags to television set receivers and satellites to mobile phones. The availability of internet access from mobile devices is growing at an exponential rate that causes rising demand on the wireless network and mobile devices' performance. As the type of activities that consumers are engaging in over the wireless connections is changing day in day out, it has been an increased need for the devices to change also. For instance in radios, the increasing quantity of mobile internet traffic there has been increased the need for additional frequency for support. The modern world is becoming an intelligent interactive environment that has needs novel autonomous sensors with wireless communication links that require to be incorporated into an everyday object. This is the reason why sensors that are nanoenabled integrated with small RF transceivers are useful in monitoring air quality, water pollution among other aspects. The main drivers of changing into nanotechnology in wireless devices are needed for high performance, reduced consumption of power as well as reduced compact size.

The ultrawide-band antenna is one of the hot research areas. Based on the conventional ultrawide-band circular disk monopole antenna, a novel miniaturized ultrawide-band monopole antenna is presented in this paper. The simulation results demonstrate that the antenna can work well in the 2.3GHz∼24GHz frequency range. Compared with the conventional antenna, the novel antenna has better omnidirection in H-plane radiation pattern. It is proposed to be used in mobile communication and satellite communication with good prospects.

The importance of the development of laser telemetry for reception of scientific data from space is pointed out by J. Bland-Hawthorn et al. in their Policy Forum “Laser telemetry from space” (26 July, p. 523). The authors consider the limitations to data communication in the microwave range due to spectrum allocations, but they do not consider the fundamental limitations for both radio and optical communications due to the signal-to-noise average power ratio as expressed by Shannon ([1][1], [2][2]). The spectrum allocation limit is relevant for near-Earth applications, but for the important case of communication at distances of 0.1 astronomical units (AU) and beyond, the signal-to-noise limit is dominant. At large distances, the radio and optical communication rates feasible in the next 15 years are comparable. This situation is illustrated in the figure, which plots data rate as a function of distance for three cases: (i) NASA's current radio Deep Space Network (DSN), (ii) optical technology expected to be available by 2010, and (iii) a future large radio array, such as discussed recently in Science (“Tuning in the radio sky,” R. Irion, 3 May 2002, p. [830][3]). ![Figure][4] Comparison of current and future radio and optical communication rates at astronomical distances. Data rate ( 3 ) versus distance for DSN (blue), expected optical technology (purple), and a future large radio array (red). The leveling off of the radio data rate at distances less than 0.2 AU (about 30 million km) is due to spectrum allocations of 50 MHz for the current DSN at 8.4 GHz and 500 MHz at 32 GHz for a future large array. The data rate in bits/second can exceed the bandwidth in hertz by using multilevel coding but has a flat logarithmic dependence on signal-to-noise ratio and, hence, distance. At the distance of Jupiter, the current radio data rate is limited by signal-to-noise ratio on the order of 50 kbits/s, which is three orders of magnitude lower than the spectrum allocation. An important goal is video data rates from the outer planets, which requires on the order of 5000 kbits/s. This rate is feasible with SKA-class large radio arrays that are under development for radio astronomy and are under consideration by NASA for space communications. Other factors such as the proven reliability of current spacecraft radio transmitters, sensitivity to location of the sun, spacecraft vibration and pointing requirements, and availability due to weather conditions (clouds) all need to be considered. Radio spectrum allocations of several GHz in the 100-GHz frequency range have yet to be explored. Both optical and radio communications need to be developed for future space communications of scientific data. 1. 1.[↵][5]1. C. Shannon , Bell System Tech. J. 27, 379 (1948)623. [OpenUrl][6][CrossRef][7][Web of Science][8] 2. 2.[↵][9]The Shannon limit is given by C = B .log2 (1 + S / N ), where C is the data rate in bits/s, B is the channel bandwidth in Hz, and S and N are the average signal and noise powers. It is important to note that N is proportional to B and refers to additive noise due to background sources and detectors and not the fluctuations due to the Poisson distribution of signal photons. 3. 3.The data rates in the figure are all for 50 W of DC power consumption and similar communication equipment mass of 18 kg at the spacecraft and assume 9 dB of link margin to account for atmospheric variations, error-correction coding efficiency, and component degradations. The 2010 optical link assumes a 10-m receiving antenna on Earth, a 0.3-m-diameter transmit antenna, a background noise level (daytime) of 10 quanta, and a data rate increase of of 1/ln 2 = 1.442 allowed by the Shannon limit for an optimum bandwidth much greater than data rate. The current radio link assumes a 70-m DSN antenna, 1.5-m-diameter transmit antenna, and total system noise of 54 quanta ( T sys = 22 K at 8.4 GHz). The future large array assumes 3600-by 12-m-diameter antennas, 1.5-m transmit antenna, and total system noise of 26 quanta ( T sys = 40K at 32 GHz). # Response {#article-title-2} Radio communication technology has been around for a very long time and is now so nearly optimized that little improvement can be anticipated unless increasingly large and correspondingly costly antenna arrays are constructed. Optical/near-infrared communications are still in their infancy. But, in many applications, the high inherent bandwidth of optical frequencies should ultimately make them far more powerful than radio waves. Our Policy Forum anticipated that near-infrared telemetry techniques would take the lead in communication across space sometime in the next decade. Weinreb correctly points out the importance of Shannon's limit on data transmission rates in telemetry across vast stretches of space. Our Policy Forum took this limit into full account, albeit without specific mention. For transmission from the astronomically important Lagrangian point L2 at 0.01 AU, Weinreb's plot clearly illustrates the large advantage that optical telemetry has even over the most ambitious currently projected radio techniques. Over greater interplanetary distances, Weinreb's plot shows the future radio array winning out at radio frequencies, but this is only because he compares laser transmission with a relatively small 0.3-m transmitting antenna to radio transmission with a 1.5-m-diameter antenna. With comparable transmitting dishes, the two systems would perform equally well. For regular access from space, ground receiving stations need to be distributed around the globe to assure communication at all times of day. The anticipated ground stations for near-infrared telemetry are expected to be affordable and more easily installed at widely distributed sites. The billion-dollar Square Kilometer Array will be a wonderfully powerful astronomical instrument, but it should, and most probably will, be used primarily for exquisitely sensitive radio astronomical observations rather than for spacecraft telemetry. [1]: #ref-1 [2]: #ref-2 [3]: /lookup/doi/10.1126/science.296.5569.830 [4]: pending:yes [5]: #xref-ref-1-1 View reference 1. in text [6]: {openurl}?query=rft.jtitle%253DBell%2BSystem%2BTech.%2BJ.%26rft.volume%253D27%26rft.spage%253D379%26rft_id%253Dinfo%253Adoi%252F10.1002%252Fj.1538-7305.1948.tb01338.x%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [7]: /lookup/external-ref?access_num=10.1002/j.1538-7305.1948.tb01338.x&link_type=DOI [8]: /lookup/external-ref?access_num=A1948UH03900001&link_type=ISI [9]: #xref-ref-2-1 View reference 2. in text

Polymer matrix composites with lightweight, low dielectric constant (ε) and dielectric loss tangent (tan δ), high‐temperature resistance, and excellent mechanical properties are urgently needed in the fields of aviation, aerospace, transportation, and wireless communication services. In this work, 3D woven spacer Kevlar/polyimide composites (3DKPC) with excellent dielectric properties and robust mechanical properties were designed and obtained by combining 3D weaving technology and thermal imidization process. Results show that the volume density of the prepared composites is as low as 0.24 g·cm −3 , but its compressive strength can be up to 6.24 MPa. The dielectric constant and loss tangent of 3DKPC at room temperature are extremely low, with the value of ~1.32 and 6.9 × 10 −3 , respectively. Moreover, the compressive strength retention rate is more than 96% and the dielectric constant can be consistently lower than 1.36 when the temperature increases from 25 to 300°C, demonstrating the outstanding mechanical and dielectric stability of 3DKPC. In addition, as an application example of resulting composites, a microstrip antenna with 3DKPC as the substrate material was designed, followed by the simulation of its electromagnetic properties via High Frequency Structural Simulator. The results display that the gain of the microstrip antenna is 6.2 dB, which is superior to those of many other reported microstrip antennas, indicating that the 3DKPC proposed here has great application potential in aerospace, wireless communication, and other fields.