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The rectangular microstrip patch antenna (RMPA) had designed and manufactured to operate in two working areas of the worldwide interoperability for microwave access (WiMAX) communication system. Flame retardant (FR-4) material had used for implementation, and the total antenna size was 57.22 × 1.6 mm 3 . The chemical method was used to implement the RMPA. The proposed antenna is capable of working at frequencies 2.51 GHz and 3.87 GHz experimentally. The results were -21.62 dB of return loss, and 50 MHz of bandwidth for the first frequency. Also, for second frequency was -20.01 dB of return loss, and 80 MHz of bandwidth.

In this proposed research article, four-port dual notched bands multiple-input-multiple-output (MIMO) antenna configuration is proposed and is experimentally investigated by fabricating prototype. Initially, a single element is fabricated which is converted to 2 × 2 MIMO configuration and finally to 4 × 4 MIMO configuration. The proposed MIMO antenna is designed to cover impedance bandwidth of 3.15–11.36 GHz and hence is useful in applications for ultrawideband and X-Band applications. Two interfering bands, WiMAX (3.30–4.05 GHz) and WLAN (4.90–5.99 GHz) are eliminated by using an inverted T-shaped stub and C-shaped slot on the radiating patch of the MIMO antenna. The proposed MIMO antenna offers good diversity performance with envelope correlation coefficient < 0.02, directive gain > 9.95 dB and total active reflection coefficient ≤ 20 dB in the entire operating band. Also, antenna gain is stable in the entire operating band except in interfering bands with a maximum radiation efficiency of more than 80% and stable radiation pattern. All the above said features make the proposed antenna suitable for high-speed wireless network applications.

Presented is an electrically small multiband monopole antenna based on complementary split-ring resonators, which are used to reduce antenna size. The antenna is fed by a three-stage microstrip line and provides 13, 17 and 16% impedance bandwidth performance covering the 3.5 GHz WiMAX and 2.4/5.2 GHz WLAN bands. Also, the proposed antenna exhibits almost an omnidirectional radiation pattern in the H-plane and a dipole-like radiation pattern in the E-plane. The return loss and radiation pattern measurements of the fabricated antenna are in very good agreement with simulation results.

In this manuscript, a compact superwideband monopole antenna with triple notched band characteristics is presented and is experimentally investigated. Proposed antenna is also suitable for lower band of applications including Bluetooth and LTE2600 bands. Superwideband bandwidth with bandwidth ratio ≥ 10:1 is obtained by using two identical ellipse which are placed at 70° with reference to major axis. A fractal stub is used to notch WiMAX interfering band while WLAN and DSS bands are notched by etching modified rectangular slots on the radiating patch. Antenna also constitutes slotted ground with chamfered corners for better matching of impedance. Proposed antenna is also investigated in terms of frequency, time and space domain. Antenna offers a wider superwideband bandwidth with VSWR ≤ 2 for 2.34 GHz to 20.00 GHz. In time domain, antenna offers constant group delay in entire operating bandwidth and acceptable impulse response for input signal. Also, antenna offers maximum gain of 4.98 dBi and radiation efficiency of 89%. Stable radiation pattern and above features of proposed antenna suggest antenna to be a good candidate for numerous applications in wireless system.

In this manuscript a compact multiband antenna with dimension 16 × 18 × 0.787 mm 3 is presented for multiple wireless applications including Digital Cellular System (1.71–1.88 GHz), Personal Communication System (1.85–1.99Gz), Bluetooth Wireless System (2.402–2.480 GHz), WiMAX (3.30–3.80 GHz), WLAN (5.150–5.825 GHz) and X-Band Downlink System (7.25–7.75 GHz). Radiating patch consist of a glass shape and a rectangular ground plane. Two resonating bands (DCS, PCS and Bluetooth Wireless System) is obtained by inserting stubs whereas remaining bands (WiMAX, WLAN and X-Band Downlink System) is obtained by etching slots on the radiating patch. There is a close agreement between simulated and measured results which is obtained by fabricating prototype.

Antennas in wireless sensor networks (WSNs) are characterized by the enhanced capacity of the network, longer range of transmission, better spatial reuse, and lower interference. In this paper, we propose a planar patch antenna for mobile communication applications operating at 1.8, 3.5, and 5.4 GHz. A planar microstrip patch antenna (MPA) consists of two F-shaped resonators that enable operations at 1.8 and 3.5 GHz while operation at 5.4 GHz is achieved when the patch is truncated from the middle. The proposed planar patch is printed on a low-cost FR-4 substrate that is 1.6 mm in thickness. The equivalent circuit model is also designed to validate the reflection coefficient of the proposed antenna with the S11 obtained from the circuit model. It contains three RLC (resistor–inductor–capacitor) circuits for generating three frequency bands for the proposed antenna. Thereby, we obtained a good agreement between simulation and measurement results. The proposed antenna has an elliptically shaped radiation pattern at 1.8 and 3.5 GHz, while the broadside directional pattern is obtained at the 5.4 GHz frequency band. At 1.8, 3.5, and 5.4 GHz, the simulated peak realized gains of 2.34, 5.2, and 1.42 dB are obtained and compared to the experimental peak realized gains of 2.22, 5.18, and 1.38 dB at same frequencies. The results indicate that the proposed planar patch antenna can be utilized for mobile applications such as digital communication systems (DCS), worldwide interoperability for microwave access (WiMAX), and wireless local area networks (WLAN).

A very simple triple-band circularly polarised printed monopole antenna with bandwidth enhancement for 2.45/5.8 GHz wireless local area network (WLAN) and 3.5 GHz worldwide interoperability for microwave access (WiMAX) applications is presented. The circular polarisation characteristic at the WiMAX band was obtained by an inverted-U-shaped radiator rotated by 45° around the horizontal axis. To create the upper circular polarisation mode at the 5.8 GHz WLAN band, an I-shaped strip was added on the right side of the radiator. Finally, by attaching an inverted-L-shaped strip at the end of the I-shaped strip, the lower circular polarisation characteristic at the 2.45 GHz WLAN band was achieved. The proposed antenna is excited by a simple 50 Ω microstrip feed line using a transformer for impedance matching. The measured −10 dB impedance bandwidth is 450 MHz (2.35–2.8 GHz) and 4.1 GHz (3.3–7.4 GHz) and the measured 3 dB axial-ratio bandwidth reaches 12% (2.35–2.65 GHz), 10% (3.3–3.65 GHz) and 4.4% (5.6–5.85 GHz).

This paper presents a metamaterial inspired antenna with tapered patch for operating in 2.5 GHz, 3.5 GHz, 4.6 GHz, and 5.8 GHz frequencies of WLAN/WiMAX applications. The resonant modes obtained by the implementation of CSRR and modified patch structure. The negative permittivity characteristics of the CSRR is discussed along with its equivalent circuit. The proposed antenna is also fabricated using the low cost FR4 Epoxy substrate with dielectric permittivity of 4.4, height of the substrate is 1.6 mm and loss tangent 0.02 and measured for the validation of the design. The proposed antenna achieved gains of 6.06 dBi, 12.1 dBi, 15.1 dBi, 4.6 dBi in 2.5 GHz, 3.5 GHz, 4.6 GHz, and 5.8 GHz respectively. Stable radiation patterns were also observed in the same operating regions.

The new WiMAX technology offers several advantages over the currently available (GSMor UMTS-based) solutions. It is a cost effective, evolving, and robust technology providing quality of service guarantees, high reliability, wide cov- erage and non-line-of-sight (NLOS) transmission capabilities. All these features make it particularly suitable for densely populated urban environments. In this paper we discuss the design and implementation difficulties concerning network coverage discovered in a test-bed implementation of WiMAX. We point out the presence of unexpected “white spots” in the coverage, which are not inherently characteristic of the WiMAX concept. As a possible remedy to this significant drawback of the otherwise very promising technology, we consider reconfigurable mesh organization of WiMAX base stations. We also suggest directions for further development of this kind of network operation, partly based on our practical experience. Despite the clear advantages of the mesh mode in WiMAX networks, its development is currently at an early stage, due to the high complexity of the necessary mechanisms. In this situation, we propose an original, much simpler solution: the so-called support-mesh mode.

Existen múltiples tecnologías para el transporte de info-comunicaciones, entre objetos y máquinas para internet. Dos de las más robustas y de mayor cobertura y que soportan múltiples usuarios son 4G y WiMax IEEE 802.16x. En este trabajo se presenta una simulación de cobertura terrestre de ambas tecnologías de comunicación inalámbrica, como alternativa de comunicación de banda ancha para nuevos operadores libres, privados o soportados por instituciones públicas como municipalidades o cooperativas regionales. Se estudiaron los casos de las ciudades de Riga, Bucarest, Florianópolis, Santiago, Concepción y Copiapó. El estudio utiliza el software Radio Mobile GLOBE-BIL (Versión 11-3-7), obteniéndose gráficas de cobertura de propagación sobre mapas digitales de elevación de terreno SRTM liberados por la NASA. Esta simulación determina el número de antenas requerido para millones de usuarios en el contexto del Internet de las Cosas, así como cuantificar los kilómetros cuadrados de cobertura de propagación inalámbrica que se pueden alcanzar técnicamente para cada una de las ciudades del proyecto. Los resultados obtenidos muestran que WiMax soporta mayor cantidad de usuarios conectados, posee mejor cobertura y requiere menor número de antenas. Por otro lado, para el indicador de cobertura de propagación, los resultados para 5 ciudades son mejor la tecnología WiMax que 4G, salvo Santiago (Chile), donde se alcanza el mejor rendimiento para 4G sobre WiMax.