Satyadeep Das

Compact multiband CPW antenna with fractal stub

High Frequency Inset-fed compact CPW slot antennas a conventional wideband slot antenna with fractal stub modified by a parasitic line surrounding the fractal stub, affecting the multiband operation suitable for applications in wireless communication system. The proposed antenna resonates at four frequency bands at centre frequencies 4.25, 5.55, 8.5, 9.3 GHz. The first resonant band extends from 3.6GHz to 4.2GHz which is the operation band of wireless. Effectively consistent radiation pattern and gain have been observed. The proposed antenna is small and compact in size, providing consistent radiation pattern, broadband impedance matching and approximate gain characteristics. The proposed antenna is size reduction of 62.5%.

A compact dual-band microstrip line fed slot antenna with two symmetrical inverted L-shaped stubs for WLAN application

The paper presented here, is a compact microstrip line fed slot antenna. This antenna is associated with two symmetrical inverted L-shaped stubs. This antenna is mainly useful for WLAN application. The proposed antenna is having the dimensions 30×30mm2. The impedance bandwidths of proposed antenna are measured at the resonant frequencies of 2.47GHz and 5.46GHz which cover the required bandwidth of WLAN communication application. At the two operating bandwidths the gains of the proposed antenna are measured which are suitable for the operation in WLAN band of frequencies. The working mechanism of the proposed antenna is analyzed and the simulated result for reflection coefficient (s11) is found out. The surfacecurrent distribution is also found out here. The proposed antenna is reasonably compact in nature to find adequate enough for application in contemporary wireless local area networks.

A compact coplanar waveguide-fed slot antenna with an inverted U-shaped stubs for WLAN application

A simple and compact coplanar wave guide (CPW) fed slot antenna with an inverted U-shaped stub design is presented here. The size of the proposed antenna is (18×18 mm2). It is simply composed of a square slot, an inverted U-shaped stub both in ground plane and a monopole radiator. Due to this new design the antenna can operate at two resonating frequencies i.e. at 2.38 GHz and 5.79 GHz. The prototype of this antenna is designed and simulated. After the simulation, results show the percentage bandwidths of 10.57 (at 2.38 GHz) and 6.88 (at 5.79 GHz) respectively for the proposed antenna. The value of the peak gains at 2.38 GHz and 5.79 GHz are 3.15 dBi and 3.39 dBi respectively which are sufficient for the operation of WLAN system satisfactorily. This proposed antenna demonstrates a consistent co-polar and permissible cross-polar radiation patterns in the desired bands of frequencies.

Square fractal ring loaded CPW-fed circular polarized antenna

The design of a printed monopole antenna loaded with square-ring for circular polarization (CP) is presented. CPW feeding is used to compact the antenna size and overcome the high impedance problem. Enhancement of axial ratio bandwidth is obtained by optimizing the length of the driven monopole antenna. The square-ring microstrip load is the parasitic element which is a compact variation of square microstrip. The multi-band microstrip antenna and the reduction in the whole antenna size are realized by applying fractals to the two opposite sides of the ring. Here, the multi-band frequency response of the fractal ring loaded monopole antenna is studied using HFSS software. Detailed design results from parametric simulations are presented and parameters study including the width of the parasitic ring element and lengths of feeding line and radiating patch are involved.

Dual band metamaterial inspired monopole antenna for mobile communications

In this paper a dual band metamaterial loaded monopole antenna is proposed using a 5-element linear array of hexagonal omega metamaterial structure loading in the opposite side of the ground. The proposed antenna has compact size of 51.9 × 51.9 × 1.6 mm (0.382λ0 × 0.382λ0 × 0.01λ0) at 1.9GHz. The proposed antenna structure can provide dual band operation at resonant frequencies 1.9GHz and 3.6GHz with return loss of -24dB and -26dB respectively. The CPW-fed line is employed to improve the impedance matching of the antenna. The proposed antenna is suitable for operation in 3G GSM at 1.9GHz & 3.5GHz WiMAX (3.3 - 3.6GHz). The measured gain at these two operating frequencies 1.9GHz and 3.6GHz are 1.5dB and 5.5dB respectively. The frequency response of the simulation results shows good agreement with the measured results. Design methodology of the proposed antenna and experimental results are presented and discussed.

Broadband metamaterial based Resonant Cavity Antenna

A high gain planar Resonant Cavity Antenna (RCA) inspired by metamaterial superstrate is proposed operating at C-band. The RCA is modelled using simple ray tracing method. The unit cell metamaterial consists of Artificial Magnetic Conductor (AMC) and square patch laminated on either side of the dielectric material, is used as the superstrate to design RCA. Square patch is capacitive type and that AMC as inductive. Effects of the reflection phase of the substrate decides the gain of the antenna. A cylindrical dielectric resonator antenna (CDRA) has been used as the primary radiator. The metamaterial unit cell structure is characterized and its effective material parameters are extracted through its S-parameters simulation. The proposed antenna achieves 22dBi gain in the broad range of 3.4 to 7.8 GHz with only 4 × 4 array superstrate.