WiMAX Wireless Applications Research Articles

Metamaterial-based Octagonal Ring Penta-band Antenna for Sub-6 GHz 5G, WLAN, and WiMAX Wireless Applications

Metamaterial-based Octagonal Ring Penta-band Antenna for Sub-6 GHz 5G, WLAN, and WiMAX Wireless Applications

Bandwidth and gain enhancement of triple‐band MIMO antenna incorporating metasurface‐based reflector for WLAN/WiMAX applications

In this work, a compact two-element triple-band multiple-input multiple-output (MIMO) antenna loaded with reflective type metasurface (MS) for enhancing the gain, isolation and impedance bandwidth (IBW) is presented. The two-element radiator antenna consists of a microstrip feed line on the upper side of the substrate and defected ground structure (DGS) on the backside on which multiple slots are etched for obtaining triple-band antenna performance. Due to DGS loading, the entire dimensions of the single radiator antenna are reduced to 22 × 22 × 1.6 mm3 with smaller electrical dimensions of 0.17λ 0 × 0.17λ 0 × 0.012λ 0 at the first resonating frequency. The proposed two-port MIMO antenna with MS operates at 2.36–2.50, 3.43–3.50 and 5.15–5.88 GHz with percentage bandwidths of 5.76, 2.02 and 13.22% for the three operating bands. Due to MS loading, a gain improvement of 5.49, 4.57 and 0.80 dBi is noticed with a maximum gain of 3.98, 5.25 and 2.66 dBi is obtained at the three operating frequencies of 2.46, 3.51 and 5.32 GHz, respectively. The intended antenna is appropriate for working in IEEE 802.11 b/g/n (2.4–2.484 GHz) WLAN, IEEE 802.11 a/h/j (5.15–5.825 GHz) WLAN, and IEEE 802.16e (3.4–3.5 GHz) WiMAX wireless applications.

Hexagonal shaped fractal MIMO antenna for multiband wireless applications

A hexagonal shaped fractal Multiple input Multiple Output (MIMO) antenna resonates to six different frequencies is presented. A dumbbell structure with hexagon shaped defected ground structure (DGS) is created in the ground plane. Two antenna elements sharing a common ground plane are positioned orthogonal to each other for better isolation. The antenna is designed, fabricated using FR4 substrate with 1.6 mm thickness and tested experimentally. The antenna provides high peak gain of 8.69 dBi at 8.33 GHz. The multiband MIMO antenna resonates for the frequencies 1.9 GHz, 2.9 GHz, 3.2 GHz, 5.0 GHz, 5.6 GHz and 7.74 GHz. Mutual coupling is better than − 20 dB and the peak gain of the antenna ranges from 3.2 to 8.69 dBi. The designed orthogonal two element MIMO antenna is suitable for GSM, PCS, WLAN and Wi-MAX wireless applications. Simulation work is carried out by ADS tool and fabricated antenna is tested with vector network analyser.

Design and development of triple-band compact ACS-fed MIMO antenna for 2.4/3.5/5 GHz WLAN/WiMAX applications

In this paper, a very small size (20 × 14.75 mm2) triple-band multiple-input multiple-output (MIMO) microstrip patch antenna for WLAN (2.4/5.2/5.8 GHz) and WiMAX (2.5/3.5/5.5 GHz) wireless applications. The goal of this paper is to merge these two wireless standards into a single antenna that can be easily accommodated inside the devices operating in three different frequency ranges. The proposed MIMO antenna consists of an asymmetric coplanar strip (ACS) feedline loaded with an inverted L-shaped slot and a meanderline. The inverted L-shaped slot and the meanderline both having an electrical length 0.5λ, are responsible for the achieving the operating band around 3.5 and 2.4 GHz, respectively whereas the ACS feedline is responsible for the generation of 5 GHz frequency band. The fabricated prototype of the proposed MIMO antenna when tested, shows three distinct frequency bands; I from 2.38 to 3.00 GHz, II from 3.21 to 3.61 GHz and III from 5.02 to 6.18 GHz that covers entire frequency bands of WLAN and WiMAX wireless applications along with different standards of IEEE 802.11 including a/b/j/p/g/n/ac/ax. The peak gain in I, II and III frequency bands is 7.93, 4.23 and 7.57 dBi, respectively. In addition, the diversity performance in terms of envelope correlation coefficient, diversity gain, multiplexing efficiency, total active reflection coefficient, and mean effective gain is also performed for the proposed MIMO antenna.

A Wearable Dual-Band Low Profile High Gain Low SAR Antenna AMC-Backed for WBAN Applications

A dual-band, low profile, high gain, and low specific absorption rate (SAR) triangular slotted monopole antenna backed with a 4×4 artificial magnetic conductor (AMC) array is presented for wireless body area network (WBAN) applications. The antenna is printed on a Rogers ULTRALAM 3850 substrate, whereas the AMC array is printed on a RO3003 substrate. The design operates at 3.5 GHz, for WiMAX wireless applications, and at 5.8 GHz for the ISM Band. The proposed antenna preserved the dual-band resonance and exhibited acceptable gain and SAR at a separation of 15 mm from the human body model. To reduce such separation and achieve enhancements to gain and SAR, an AMC array was utilized. In free space, gain enhancements by 6.8 and 3.7 dBi were achieved at both frequencies, respectively. Furthermore, over a gap of 1 mm from the human body, gain enhancements by 23.3 and 13.9 dBi were achieved at both frequencies, respectively. In addition, SAR reductions by almost 99% were attained. The antenna was fabricated and measured where a very good agreement was observed between simulated and measured results, with and without the incorporated AMC array. With such results, the proposed design can be highly recommended for wearable medical applications, specifically for diabetic patients.

Single layer single probe feed circularly polarized triple band fractal boundary microstrip antenna for wireless applications

Triple band circularly polarized fractal boundary microstrip antenna is proposed and experimentally studied. The two orthogonal sides of the square patch are replaced with asymmetrical fractal curves for circular polarization (CP) radiation. A 45° rotated asymmetrical fractal slot is embedded at the center of the fractal patch for triband CP operation. The indentation factors of the fractal curves are optimized for better CP emission. The inserted fractal slot redistributes the current elements on the patch for triband CP radiation. The proposed antenna is implemented over a single layer with a single probe feed, so it is simple to fabricate and is cost effective when compared with the existing stacked layered multiband antennas in the open literature. The measured 3 dB axial ratio bandwidths of the proposed antenna at 2.4, 3.4, and 5.8 GHz are 2, 1, and 1.8%, respectively, so it is well suited for WLAN and Wi-MAX wireless applications.

Poly Fractal Boundary Circularly Polarised Microstrip Antenna for WLAN/Wi-MAX Wireless Applications

<p class="MsoNormal" style="text-align: justify;">The design of circularly polarised multiband poly fractal boundary microstrip antenna is proposed and experimentally studied. Initially the two orthogonal sides of the square patch are replaced with different fractal curves for circular polarisation (CP) radiation. Along the x and y axes, Minkowski and Koch fractal curves are employed. A 45° rotated poly fractal slot is embedded at the center of the fractal patch for triband CP operation. The indentation depths and indentation angles of the Minkowski and Koch fractal curves are optimised for better CP emission. The inserted fractal slot redistributes the current elements on the patch for tri band CP radiation. The measured 3-dB axial ratio bandwidths of the proposed antenna at 2.4 GHz, 3.4 GHz, and 5.8 GHz are 1.53 per cent, 0.81 per cent, and 1.62 per cent respectively, making it an able candidate for WLAN and Wi-MAX wireless applications.</p>