Santosh Kumar Chowdhury

Compact Dual-Band Microstrip Antenna for IEEE 802.11a WLAN Application

A compact dual-band rectangular microstrip antenna (RMSA) is realized by two different single-slotted single-band rectangular microstrip antennas with slotted ground plane. Each open-ended slot in the single-slotted antenna is responsible to generate a wide impedance band that is shifted to lower frequencies by the effect of the ground slot. The length and position of each open-ended slot is varied to operate the antenna in a suitable resonant band (5.15-5.35 and 5.725-5.825 GHz). The proposed antenna meets the required impedance bandwidth, necessary for dual-band IEEE 802.11a WLAN application (5.125-5.395 and 5.725-5.985 GHz). The dimension of the antenna (12 × 8 × 1.5875 mm3) shows an average compactness of about 53.73% with respect to a conventional unslotted rectangular microstrip patch antenna.

A COMACT MICROSTRIP PATCH ANTENNA FOR WIRELESS COMMUNICATION

A single feed compact rectangular microstrip antenna is presented in this paper. A triangular slot is introduced at the upper edge of the patch to reduce the resonant frequency. A small piece of triangular patch is added within the area of the triangular slot to improve the gain bandwidth performance of the antenna. The antenna size has been reduced by 46.2% when compared to a conventional square microstrip patch antenna with a maximum of 160MHz bandwidth and i27:36dB return loss. The characteristics of the designed structure are investigated by using MoM based electromagnetic solver, IE3D. An extensive analysis of the return loss, radiation pattern, gain and e-ciency of the proposed antenna is shown in this paper. The simple conflguration and low proflle nature of the proposed antenna leads to easy fabrication and make it suitable for the

Analysis of a Miniaturized Multiresonant Wideband Slotted Microstrip Antenna With Modified Ground Plane

In this letter, a miniaturized slotted microstrip antenna with modified ground plane for multiresonant wideband operation is proposed. The miniaturized antenna dimension is only about 24 (0.44λr) ×22 (0.403λr) mm2, where, λr is the wavelength of the resonant frequency of the conventional antenna (i.e., 5.5 GHz). The measured result shows two distinct resonant frequencies at 2 and 3.3 GHz. A -10-dB wide-impedance bandwidth of 3100 MHz ranging from 4.2-7.3 GHz is also achieved for the proposed antenna structure. The measured result shows that the size of the proposed antenna has been reduced by 67% in comparison to the conventional rectangular microstrip antenna with same area, and the operating bandwidth is also enhanced up to 53.9%.

Effect of different slots in a design of microstrip antennas

A signal layer rectangular microstrip antenna embedded with open-ended and close-ended slots is presented in this paper. Two open-ended slots are introduced inside the ground plane as well as inside the patch to excite the antenna with different resonant mode. In another configuration, two close-ended slots are introduced both inside the ground plane and patch to observe the variation in resonant frequency and bandwidth of the antenna. The proposed structure showed promising results in perspective of return loss, gain, efficiency and directivity for the applications wireless communication system including IEEE 802.11a WLANs application that allocate channels between 5.15 to 5.825 GHz.

Design and Analysis of a Compact Triple Band Slotted Microstrip Antenna with Modified Ground Plane for Wireless Communication Applications

A novel single layer, coaxial probe feed compact triple band slotted microstrip patch antenna with modifled ground plane for wireless application has been designed and analyzed. The presented antenna, occupying a compact size of 24 £ 22 £ 1:6mm 3 , embodies a rectangular slotted patch and a rectangular ground plane modifled with open ended step graded slots. The step graded slots are introduced on the ground plane to reduce the size of the antenna by reducing the resonant frequency and also to improve the operating bandwidth of the proposed antenna. The size of the antenna has been reduced by 74% by introducing slots on the ground plane. The measured bandwidths for i10dB re∞ection coe-cient are 360MHz (1.72{2.08GHz) at lower band, 300MHz (3.36{3.66GHz) at middle band and 3650MHz (4.85{8.5GHz) at upper band which cover the bandwidth requirements of 1.92GHz PCS, 1.9GHz PHS, 3.5/5.5GHz WiMAX, 5.2/5.8GHz WLAN, 5.2GHz HisWaNa and 5GHz HiPERLAN wireless application bands.

Dispersion characteristics of curved microstrip transmission lines

An empirical expression for the effective dielectric permittivity of curved microstrip transmission lines is derived. This expression is very general because it can also be used for rectangular microstrip lines by considering a rectangular line as a curved line of infinite radius of curvature. The closed-form expression for the frequency dependence of the effective dielectric permittivity of a rectangular microstrip line is compared with other available results. This expression for the frequency dependence of the effective dielectric permittivity of curved microstrip transmission lines is simple, accurate, and suitable for CAD implementation. The measured and computed results for various curved microstrip lines are compared, and excellent agreement between the two is obtained. >

Modified π-shaped Slot Loaded Multifrequency Microstrip Antenna

A single layer, single feed microstrip antenna with multifrequency operation in compact size is proposed. A modified inverted π-shaped slot is introduced at the left side radiating edge of the patch to reduce the size of the antenna by reducing the resonant frequency. Multiple resonant frequencies with increased frequency ratio are also obtained by cutting the modified inverted π-shaped slot. The measured result shows that the proposed antenna resonates at 3.3, 4.55, 5.56 and 6.08 GHz in microwave S and C band. The size of the proposed patch is only 0.176λL × 0.132λL at its lower operating frequency. The proposed patch antenna has achieved 68% size reduction as compared with the conventional rectangular microstrip antenna with same patch area. An extensive analysis of the reflection coefficient, voltage standing wave ratio, gain, radiation efficiency and radiation pattern of the proposed antenna is presented in this paper. The proposed antenna is suitable for WiMax and HiPERLAN wireless systems.

UWB monopole antenna design in a different substrate using Sierpinski Carpet Fractal Geometry

In this paper an Ultra Wideband Monopole antenna is designed for various WLAN and WiMAX applications. The antenna is designed using CST Microwave Studio SuiteTM. Iterative patch structures are considered to obtain optimized result. Also obtain optimized result using different substrate. Sierpinski Carpet Geometry is applied in design of the patch structure. The finalized monopole is proposed to be applicable in the WLAN bands (5.2/5.8 GHz) and WiMAX bands (3.5/5.5 GHz). The antenna exhibits a gain of 2.8 dB, 3.6 dB, 3.8 dB and 3.9 dB at frequencies 3.5 GHz, 5.2 GHz, 5.5 GHz and 5.8 GHz respectively. The antenna exhibits a wide bandwidth of 3.5 GHz to 7.5 GHz respectively.

Coupling factor of H-plane coupled rectangular microstrip antennas

Mutual coupling between rectangular half wavelength microstrip antennas fed by a coaxial line at the center of one of the radiating edges is investigated. A closed-form expression for the mutual coupling is developed for the H-plane configuration by which the coupling factor of these antennas may be accurately computed. The agreement between the theoretical model and measurement by previous researchers is fairly good. This expression can be readily used in the computer-aided design of microstrip antenna arrays.<<ETX>>

Compact Slotted Microstrip Patch Antenna with Multiband Characteristics for WLAN/WiMAX

In this paper, we present a compact slotted microstrip patch antenna whose multiband characteristics have been studied. This antenna is compact in shape and size having a dimension of 24 × 24 mm2. This antenna consists of two inverted F-shaped slots in the patch and a defected ground plane for enhancement of impedance bandwidth. This patch is fed by a coaxial probe. The antenna shows multi band characteristics, i.e., from 1.94–1.98 GHz, 2.4–2.52 GHz, 3.2–3.38 GHz, 5.07–5.41 GHz, 5.73–6.09 GHz. After analyzing all necessary characteristics in perspective of gain, bandwidth, polarization, and return loss, the proposed patch is well applicable for WLAN (2.4/3.2/5.2/5.8 GHz) and WiMAX (5.5 GHz) communications.