X-band Satellite Applications Research Articles

A compact wideband circularly polarized fractal slot antenna with rectangular island for X-band satellite applications

A compact wideband circularly polarized fractal slot antenna with rectangular island for X-band satellite applications

A Small Size Wideband M-shaped Polygonal Slot Antenna for X-band Satellite Applications

A Small Size Wideband M-shaped Polygonal Slot Antenna for X-band Satellite Applications

Circularly Polarized Double-walled SIW Fractal Slot and Hexagonal Ring Slot Antenna Array for X-band Satellite Applications

Circularly Polarized Double-walled SIW Fractal Slot and Hexagonal Ring Slot Antenna Array for X-band Satellite Applications

Wideband Circularly Polarized Exponential Slot Antenna with Rectangular Island for X-band Satellite Applications

Wideband Circularly Polarized Exponential Slot Antenna with Rectangular Island for X-band Satellite Applications

Bandwidth Enhancement of Micro Strip Square Patch Antenna with Partial Ground Plane for Wide Band Applications

This paper has focused on resolving two issues, which are to construct an antenna with wide bandwidth and an antenna that can be used for distinct wireless technologies that can operate at different frequencies. Bandwidth is the most important factor in designing micro strip patch antennas. Patch antennas are inherently narrow-band, but in today's wireless communication technology, high data rates are quite common. In order to handle these high data rates, wide bandwidth is required. In this paper, a partial ground plane technique is used to enhance the bandwidth of the antenna. A square patch antenna for wide band applications operating at a frequency band of 2 to 8 GHz has been designed using CST Microwave Studio and fabricated. Measured and simulated results are compared, and they are in good agreement. The proposed antenna covers various wireless standards such as Bluetooth (2.4 GHz), WLAN (2.4, 5.1-5.8 GHz), WiMAX (2.3-5.7 GHz), and X-band satellite applications (7.1-7.76 GHz). The proposed antenna is modeled with gl = 27.9 mm and Pl = Pw = 17 mm, exhibiting a wide bandwidth of 5.5 GHz and a fractional bandwidth of 111%. The return loss is below 10 dB for the entire frequency range.

A Compact Frequency and Radiation Reconfigurable Antenna for 5G and Multistandard Sub-6 GHz Wireless Applications

This paper presents a reconfigurable antenna operating in three modes at different frequency bands with pattern reconfiguration. Frequency and pattern reconfigurability are achieved using four PIN diodes. In particular, two diodes are mounted in the radiating part of the hexagon shape to perform the frequency reconfiguration of the antenna. The other two PIN diodes are connected with the inverted L-shaped and CPW ground by changing the main lobe beam steering to achieve the pattern reconfiguration. An antenna has been designed, fabricated, and numerically and experimentally assessed. The prototype of the antenna is fabricated on a commercially available FR-4 substrate of thickness 1.6 mm ( ε r = 4.3). Thus, the proposed antenna supports several 5G sub-6 GHz bands (3.1 GHz, 4.1 GHz, and 3.8 GHz), WiFi (2.45 GHz), as well as (7.8 GHz, 9.5 GHz) X-Band Satellite applications. The obtained results are quite promising. In particular, it is observed that the measured results are in close agreement with the simulation results, and the proposed (compact) antenna prototype can be a prospective candidate for future portable devices, sensor networks, and telecommunication applications.

Design of a Super Compact UWB Filter Based on Hybrid Technique with a Notch Band Using Open Circuited Stubs

This paper presents a new design of a super compact Ultra wideband (UWB) band-pass filter (BPF) with rejection of X-band satellite applications. For covering the UWB bandpass, the proposed filter is realized using hybrid technique which is achieved by using a Microstrip-Coplanar waveguide-Microstrip transition. The basic structure consists of a modified microstrip in the top layer and CPW in the bottom layer. Later, open-circuited stubs are embedded in the top to implement in-band transmission zeros (TZ) so as to circumvent interference. The simulated results show that the UWB bandpass filter has a high adaptation (S11 ≤ −18 dB) and insertion loss better than 0.4 dB at the passband. The impedance bandwidths are about 114% (3–11 GHz) with upper stopband extends to more than 14 GHz with a depth of greater than 38 dB. In addition, the UWB BPF shows a flat group delay performance with a variation of about 0.15 ns over the entire bandwidth. A prototype of the filter is fabricated and tested. Good agreement is achieved between measurement and simulation. The proposed UWB BPF is compact in size with overall dimensions of 14 by 9.2 mm2. Consequently, the obtained results prove that the presented filter is suitable for UWB wireless devices.

Design of a compact hexagonal structured dual band MIMO antenna using orthogonal polarization for WLAN and satellite applications

In this paper, a compact dual band multiple-input multiple-output (MIMO) antenna system for WLAN and X-band satellite applications (2.4/9.8 GHz respectively) is proposed. On the top face of the substrate, two antenna elements with a size of 20 × 24 mm2 are placed side by side and fed with matched orthogonal micro-strip lines. The two antenna elements have orthogonal polarization which can reduce the mutual coupling between its ports. The designed antenna system is fabricated and measured to validate the simulation results. The impedance bandwidths are about 370 MHz (2.19 to 2.56 GHz) and 630 MHz (9.44 to 10.07 GHz), while the obtained isolation is greater than 14 dB at the operating bands. Furthermore, the envelope correlation is less than 0.052 and 0.008 at 2.4 and 9.8 GHz, respectively. Hence the diversity gain is higher than 9.98 in the frequency bands of interest.

Design of a compact dual-band MIMO antenna with high isolation for WLAN and X-band satellite by using orthogonal polarization

ABSTRACT This paper presents a new design of a compact dual-band Multiple Input Multiple Output (MIMO) antenna with high isolation for WLAN and X-band satellite applications. The proposed antenna is realized using three slots: the first slot is used on the upper layer to create the second resonance frequency at 5.3 GHz and two symmetrical slots are etched on the bottom layer to enhance the impedance bandwidth of the two operating bands. In order to obtain a low mutual coupling, the two antenna elements have an orthogonal polarization. The simulated results show that the MIMO antenna has a high isolation (S21 ≤−22.5 dB) at the two desired bands with impedance bandwidths are about 4.15% (5.19–5.41 GHz) and 4.81% (7.30–7.66 GHz). In addition, the MIMO parameters like envelope correlation coefficient (ECC), diversity gain (DG), Total Active Reflection Coefficient (TARC), realized gain and efficiency are also analyzed.

Design of multi‐polarised quad‐band planar antenna with parasitic multistubs for multiband wireless communication

A multi-polarised quad-band planar circular disc monopole antenna consisting of a parasitic double T-stub and parasitic long and short inverted L-stubs is presented. By loading parasitic multistubs along the y-axis behind a circular patch, the antenna can yield four resonance modes at 2.5, 4.5, 5.7, and 7.7 GHz frequencies while keeping the size of 30 × 40 mm2. The proposed antenna has been fabricated and experimentally studied. The measured impedance bandwidths of 290 MHz (2.36–2.65 GHz), 540 MHz (4.28–4.82 GHz), 530 MHz (5.47–6.0 GHz), and 780 MHz (7.28–8.06 GHz), for Bluetooth, 2.4/5.8 GHz wireless local area network, 2.5/5.5 GHz worldwide interoperability for microwave access, 5.9 GHz intelligent transportation systems (ITS), downlink of Indian National Satellite System and X-band satellite applications. The 3 dB axial ratio bandwidth is 280 MHz (5.79–6.07 GHz) for the 5.9 GHz ITS band. The antenna E-field radiation has y-directed (vertical linear) polarisation at first, second, third resonance bands and slant + 45° linear polarisation at the fourth resonance band. At the ITS band, the E-field radiation has right-handed circular polarisation. In addition, the design procedure, electrical model and effects of parasitic stub dimensions on the antenna characteristics are discussed.

NOVEL TRANSFORMATION TO DESIGN TRI-BAND FILTERS

This paper introduces novel derived transformation equations to design Tri-band filters. The design utilizes the approach adopted for tri-band bandpass filter design based on asymmetric half- wavelength resonator. The obtained optimized filter by this approach is used as a reference, and the proposed transformation is applied to calculate the new filter design hardware parameters that satisfy its given specifications. The reference tri-band filter is designed to have: insertion better than 1.3 dB and return loss less than−10 dB at the resonance frequencies 1.4 GHz, 4 GHz and 5.6 GHz for L-Band DAB, Radar (G-band) and Radar (C-band) applications, respectively. To verify the transformation technique two tri-band filters are designed. The first tri-band filter is for WVL, WiMAX and WiLAN while the second tri-band filter is for UMTS, WiLAN and X-band Satellite applications. The momentum simulations for these filters show that the resulting filters specifications are: the insertion loss is better than 1.3 dB and the return loss is less than −10 dB at the resonance frequencies 1.3 GHz, 3.6 and 5.7 GHz for the first one. While the insertion loss is better than 1.4 dB and the return loss is less than −10 dB at the resonance frequencies 1.9 GHz, 5.35 GHz and 8.25 GHz for the second filter, respectively. A set of prototype of the final design of the proposed filters with optimal parameters was fabricated for experimental verification. The RT 5880 substrate is utilized in this design All the results are obtained using circuit and momentum simulation of the Agilent Design Simulator (ADS) package and the performance characteristics have been measured using the Rohde & Schwarz ZVB20 vector 4 port network analyzer. Analysis and comparison of the obtained results show that all the simulated and the measured results agree well.