Basic Rectangular Antenna Research Articles

Low-profile patch antennas for biomedical and wireless applications

Printed microstrip-fed antennas based on a slotted radiating patch are proposed herein. First, a basic rectangular antenna without any slots was designed, being suitable for wideband applications and showing impedance bandwidth of 2714 MHz for $$S_{11} < -10$$S11<-10 dB. Next, dual-band operation for worldwide interoperability for microwave access (WiMAX, from 3.11 to 3.97 GHz) and wireless local-area network (WLAN, 4.97---5.71 GHz) was obtained by including slots only on the left side of the basic design. Then, using a structure with slots on the right side of the radiating patch, WLAN operation was obtained in the frequency range of 2.865---2.096 GHz. The fourth antenna, with slots on both sides of the patch, was characterized and realized for biomedical applications at 2.45 GHz ($$S_{11} <-10$$S11<-10 dB). The proposed antennas can be realized with small ground plane size and total antenna area of only $$27.5 \times 21\,\hbox {mm}^{2}$$27.5×21mm2. This reduction in total antenna area is achieved by using a truncated patch. All the simulations were carried out using Empire XCcel. The designs were characterized based on their radiation pattern, return loss, voltage standing wave ratio (VSWR), gain, and current distribution. The simulated and measured results show good compatibility.

EFFECT OF QUADRUPLE P-SPIRAL SPLIT RING RESONATOR (QPS-SRR) STRUCTURE ON MICROSTRIP PATCH ANTENNA DESIGN

In this project, the different locations of the quadruple P-spiral split ring resonator (MI-SRR) structure are embedded in the basic rectangular patch antenna. It started with a basic rectangular microstrip patch antenna that simulated in CST Microwave Studio software. After that, four different locations (Location A, Location B, Location C and Location D) of QPS-SRR had chosen to compare its performance of return loss, resonant frequency, surface current radiation pattern, and gain. Location A is representing the antenna with the QPS-SRR at the center part of the patch while Location B has the QPS-SRR at the upper part of the FR-4 substrate. For the Location C and Location D represent the antenna with MI-SRR at the ground at antenna with MI-SRR at the other layer, respectively. Compared with the basic rectangular antenna with only – 27.082 dB, the best return loss was reached by Location A with - 34.199 dB with resonant frequency at 2.390 GHz, while the Location C only shifted the minor value to 2.394 GHz with only - 25.13 dB.