A Multiband Antenna for Satellite Communications on the Move

The design of a multiband reflector antenna for an on-the-move satellite communications terminal is presented. This antenna was designed to operate with numerous modern and future military communications satellites, which in turn requires the antenna to be capable of operation at multiple frequencies and polarizations while maintaining high aperture efficiency. Several feed antenna concepts were developed to accomplish this task, and are discussed in detail. Multiple working prototypes based on this design have been realized, with excellent performance. Measured data of individual antenna components and the complete assembly is also included.     

Flexible Wearable Pre-fractal Antennas for Personal High-Temperature Monitoring

Wireless Personal Communications - This paper proposed a new flexible and wearable antennas design based on teragon pre-fractal geometry until the third level, for monitoring high-temperature in...     

Dual-Band Flexible MIMO Antenna with Self-Isolation Enhancement Structure for Wearable Applications

A two-element dual-band flexible multiin multi-out antenna which can be used for wearable applications is proposed in this paper. The antenna consists of two radiating elements fed by coplanar waveguide, and a shielding layer, which are all made of flexible conductive cloth MKKTN260. Each radiating element is composed of two coupled split ring-shaped bending strips. The proposed antenna shows two measured impedance bandwidth(S₁₁<-10 dB) of 2.39–2.48 GHz and 5.72–5.88GHz, so that it...     

Multiband OFDM for Covert Acoustic Communications

A multiband OFDM transmitter and receiver are presented for underwater communications at low SNR. Compared with a single-band OFDMscheme, the multiband approach leads to a considerable reduction in the receiver complexity. The proposed system has been tested at sea with 16 subbands covering a total bandwidth of 3.6 kHz, at user data rates of 4.2 and 78 bit/s, and over ranges up to 52 km. At the lower rate, successful message recovery is achieved on a single hydrophone at SNRs down to ?17 dB in a benign channel. In channels with a severe delay-Doppler spread the critical SNR rises by some 4 dB. At 78 bit/s the limits of the OFDM signaling scheme are clearly revealed, but at 4.2 bit/s the performance is limited by failure of signal detection and initial synchronization.     

一种用于个人通信移动终端的四单元宽带微带天线阵

本文分析设计了一种宽带微带天线,该天线为四单元微带天线阵。在宽带单单元微带天线的基础上,采用宽带功率分配网络,组成了适用于个人通信移动终端的宽带微带天线阵。并且给出了电压驻波比的测试结果,以及对测试结果的简单分析。     

一种应用于车载通信的多频段全向天线

文中设计了一种应用于车载通信的多频段全向天线。该天线由印制于FR4 介质基板正反两面的金 属贴片组成,通过在主辐射贴片上端加载弯折枝节、在侧边加载边缘谐振单元、在背面加载电耦合电感电容(ELC)谐 振单元实现了其多频段特性;在主辐射贴片上蚀刻C 形槽拓宽了天线的中频带宽;天线的尺寸为58 mm×42 mm× 1. 6 mm。测试结果表明:S11≤-10 dB 的阻抗带宽为0. 82~0. 96 GHz、1. 7~2. 69 GHz、3. 34~3. 66 GHz、4. 81~4. 97 GHz, 覆盖了2G、3G、4G、5G 等频段。该天线具有小尺寸、宽频带以及全向性好等优点,可以应用于车载通信或其它移动 通信场景。     

Multiband Meandered Monopole Antenna for Mobile Applications

A multiband meandered monopole antenna is proposed for digital video broadcasting handheld (DVB‐H), global positioning system, personal communications service, wireless broadband (Wibro), and wireless local area network (WLAN) applications. The proposed antenna consists of a meandered line, a shorted length strip line, and a conductor strip between a meandered line and a microstrip feed line. By tuning a short strip and a conductor, a multiband impedance matching is achieved. The proposed antenna has an omnidirectional radiation and yields an antenna gain of greater than ?3 dBi in the DVB‐H band and 4.5 dBi in the Wibro and WLAN bands. Details of the proposed antenna design and experimental results are presented.     

新型圆环嵌套多频印刷天线

提出了一种具有多频特点的新型圆环嵌套印刷天线,该天线由不同直径的圆环嵌套得到。通过电磁仿真软件CST Microwave Studip进行仿真研究,结果表明嵌套圆环的外径、宽度和嵌套数目可以对其通频带中心频率、频带宽度和通频带数目进行控制。设计出了具有2．4GHz,3．5GHz,5．2GHz,5．8GHz四个通频带的共面波导馈电的单极印刷天线和以平衡微带线馈电的对称振子天线。制作了天线实物并在微波暗室中进行测试,测试结果与仿真吻合较好,该天线具有近似独立的频率可控性和较小的尺寸,可用于WLAN和WiMAX等领域。     

Miniaturized Multiband Slotted Microstrip Antenna for Wireless Applications

Wireless Personal Communications - A miniaturized multiband slotted Microstrip antenna for wireless applications is designed and its characteristics have been investigated. The proposed antenna...     

Reconfigurable Multiband Antenna Designs for Wireless Communication Devices

New designs for compact reconfigurable antennas are introduced for mobile communication devices. The uniqueness of the antenna designs are that they allow various groups of their operating frequency bands to be selected electronically. In particular, each group of frequency bands, or mode, can be made to serve several different communication systems simultaneously. These systems may include various combinations of GSM, DCS, PCS, UMTS, Bluetooth, and wireless local-area network (LAN). Therefore, by electronically selecting different antenna modes, a variety of communication systems can be conveniently served by only one antenna. One advantage is that through the different operational modes, the total antenna volume can be reused, and therefore the overall antenna can be made compact. In these designs, the selection of the different modes is achieved by either i) switching different feeding locations of the antenna (switched feed) or ii) switching or breaking of the antenna's connection to the ground (switched ground). This paper demonstrates these two designs. For the first design of switched feed, it can support GSM, DCS, PCS, and UMTS. In the second design, the antenna makes use of a switched-ground technique, which can cover GSM, DCS, PCS, UMTS, Bluetooth, and 2.4 GHz wireless LAN. The designs are investigated when ideal switches and also various realistic active switches based on PIN diodes, GaAs field effect transistor, and MEMs configurations. The designs are verified through both numerical simulations and measurement of an experimental prototype. The results confirm good performance of the two multiband reconfigurable antenna designs.     

Flexible MXene-Based Composites for Wearable Devices

In recent decades, flexible and wearable devices have been extensively investigated due to their promising applications in portable mobile electronics and human motion monitoring. MXene, a novel growing family of 2D nanomaterials, demonstrates superiorities such as outstanding electrical conductivity, abundant terminal groups, unique layered-structure, large surface area, and hydrophilicity, making it to be a potential candidate material for flexible and wearable devices. Numerous pioneering works are devoted to develop flexible MXene-based composites with various functions and designed structures. Therefore, the latest progress of the flexible MXene-based composites for wearable devices is summarized in this review, focusing on the preparation strategies, working mechanisms, performances, and applications in sensors, supercapacitors, and electromagnetic interference shielding materials. Moreover, the current challenges and future outlooks are also discussed.     

A Modified Sierpinski Carpet Fractal Antenna for Multiband Applications

The sudden growth in wireless communication area has increased the requirements of compact integrated antennas. This paper describes the design of Modified Sierpinski Carpet Fractal Antenna which resonates at six frequencies 4.825, 5.455, 6.265 GHz and 6.805, 8.02 and 9.145 GHz. Different performance parameters like radiation pattern, gain, Voltage Standing Wave Ratio, return losses are observed at all the frequencies. The FR4 glass epoxy with relative permittivity 4.4 and height 1.6 mm is used as substrate material. Antenna is fed by coaxial probe feed and simulated using ANSYS/ANSOFT HFSS V13 software. Proposed antenna has simple structure. Investigation is done between 1 and 10 GHz frequencies. The proposed antenna is fabricated and tested on the Vector Network Analyzer. The measured and simulated results of proposed antenna are compared and are found to be good agreement with each other.

     

北斗多模卫星导航天线设计

设计了一种可以工作在GPS L1、GLONASS 和北斗频段的多模卫星导航天线。采用“叠层结构”和引入宽带的带状线90°电桥,实现了天线的多频段工作。该天线易于调节,可以应用于不同的载体,具有与后端射频模块良好的集成性。     

多频印刷单极子天线的设计

〗提出一种应用于2.4/5.2/5.8 GHz WLAN和2.5/3.5/5.5 GHz WiMAX共面波导印刷单极子天线。该天线结构紧凑,可以方便地植入无线通讯设备中,有较强的实用性。此天线由50 Ω的微带传输线通过共面波导馈电的方式对具有对称结构的蝶型贴片馈电。在设计中,通过开缝和添加倾斜微带条,使天线获得的阻抗带宽可以覆盖WLAN和WiMAX频段。天线的总体尺寸为30 mm×32 mm,其结构紧凑、便于集成和加工,适合无线通讯应用。     

A Hybrid Fractal Metamaterial Inspired Multiband Antenna for Wireless Applications

Wireless Personal Communications - In this paper a multiband (hepta-band) antenna loaded with hybrid fractal structures and metamaterial cell (SRR/CSRR) is proposed to cover the wireless...     

移动通信中的智能天线技术

文章首先介绍了智能天线技术中的基本概念及其在移动通信系统中的发展和应用,然后说明了在移动通信系统中,应用智能天线技术可以提高系统的性能和容量,并可以简化系统控制。在此基础上,文章分别介绍了切换智能天线中预置波束的设计方法和自适应天线阵列中的经典自适应算法,并简介了目前智能天线技术的发展现状。     

A Planar Dual-Band Antenna for ISM/Wearable Applications

Wireless Personal Communications - In this paper, a small size, planar, dual-band antenna is proposed for ISM band applications. The antenna consists of a ground plane, a rectangular patch, and a...     

Multiband Microstrip-Fed Right Angle Slot Antenna Design for Wireless Communication Systems

This paper presents a novel multiband microstrip-fed right angle slot antenna design technique for multiple independent frequency bands. The new technique uses various slot sizes at various appropriate positions. We first propose a tri-band slot antenna consisting of three right angle slots. Then, a quad-band slot antenna is developed with four right angle slots which achieves slant ±45° linear polarization, omnidirectional pattern coverage, good antenna gain, and acceptable impedance bandwidths over all the operating frequency range. Moreover, an open-circuited tuning stub is introduced to achieve good impedance matching. Both proposed antennas are designed on a ground plane of RT/duroid 5880 substrate with a thickness of 1.575 mm. The real measurable results show that the desired frequencies used in wireless communication systems, namely, WLAN and WiMax, are efficiently achieved.