Payal Mohadikar

Ultra-wideband modified rectangular microstrip antenna

A new ultra-wideband planar microstrip antenna obtained by combining rectangular and circular shaped planar monopole patches is proposed. The optimum feed-line position is obtained individually for rectangular and circular patches by studying their surface current distributions. The rectangular and circular geometries are then merged to obtain a modified configuration. A parametric study for varying distances between the centers of the circular and rectangular patches and also for the gap between the radiating patch and the ground plane is conducted. The proposed configuration yields an optimum bandwidth of more than 8 GHz and a gain of 1 to 3 dBi over the bandwidth.

Ultra-wideband plus shaped microstrip antenna

With the advancement in personal mobile communication systems, need of antennas that gives ultra-wideband response has increased. In this paper a novel ultra-wide band plus shaped planar Microstrip antenna is proposed. The plus shaped structure is realized by combining two rectangular shaped planar monopole printed patches. A details parametric study to realize the ultra-wideband operation in 3 to 10 GHz frequency band is presented. The proposed antenna yields operating bandwidth from less than 2 GHz to more than 10 GHz with broadside co-polar gain of around 1 to 3 dBi over complete bandwidth. Due to the realized bandwidth and gain, proposed configuration can find applications in personal mobile communication, blue tooth and Wi-Fi applications in 3 to 10 GHz frequency range.

Sequentially rotated gap-coupled circular slot cut circular microstrip antennas

Circular polarized microstrip antennas are required in applications wherein an uncertainty in the direction of received signal polarization exist. In this paper an offset slot cut circular microstrip antenna to realize circular polarization in 1000 MHz frequency band is proposed. It yields axial ratio bandwidth of 10 MHz (~1.2%). To increase the axial ratio bandwidth its gap-coupled array configuration with parasitic offset circular slot cut circular patches is proposed. A maximum return loss and axial ratio bandwidth of nearly 44 (~4.5%) and 18 MHz (~2.0%), respectively is obtained in gap-coupled configuration of circular patches along y-axis. The proposed configurations yields broadside radiation pattern over entire bandwidth with antenna gain of more than 4 dBi in their suspended variation. The proposed gap-coupled array configuration can find applications in mobile communication environment in 1000 MHz frequency band.

Broadband varying angle shorted sectoral microstrip antennas with rectangular slot

Broadband shorted Sectoral microstrip antennas with rectangular slot for Sectoral angle increasing from 50° to 120° are proposed. In shorted patch, rectangular slot reduces the resonance frequency of shorted higher order TM1/4, 1 mode and along with fundamental shorted TM1/4, 0 mode, yields broadband response. A maximum bandwidth of nearly 2000 MHz (>70%) is realized in shorted slot cut 120° Sectoral patch whereas shorted slot cut 50° Sectoral patch yields bandwidth of nearly 500 MHz (~50%). Due to shorted patch proposed antennas shows higher cross polar level radiation pattern thereby realizing elliptical polarization over a complete bandwidth. The antenna gives gain of around 2 to 3 dBi over the bandwidth. The proposed configurations can find applications in multi-path propagation environment wherein they will lead to lesser signal loss.

Dual-band dual polarized D-shaped microstrip antenna

Design and analysis of novel dual-band dual polarized D-shaped microstrip antenna is proposed. The D-shaped microstrip antenna excites TM10 and TM01 modes which are orthogonal to each other, thereby realizing dual polarized antenna characteristics. Further, another novel configuration, a vertical slot cut D-shaped patch is proposed. The slot cut D-shaped patch demonstrates triple band dual polarized antenna response, with bandwidth of 1 to 2% at each of the frequencies in 1000 MHz frequency range. The proposed dual-polarized configuration yields broadside radiation pattern across all the resonant modes.

Sequentially rotated gap-coupled angular slot cut circular Microstrip Antenna arrays

Circularly polarized sequentially rotated gap-coupled array configuration of angular Sectoral slot cut circular Microstrip Antenna in 1000 MHz frequency band is proposed. The angular Sectoral slot degenerates TM11 mode into two orthogonal modes to give axial ratio and VSWR bandwidth of 10 and 43 MHz, respectively, in a single patch. To increase gain and axial ratio bandwidth, sequentially rotated gap coupled array configurations of angular Sectoral slot cut circular microstrip antenna are proposed. On thinner glass epoxy substrate, maximum VSWR and axial ratio bandwidth of 52 and 32 MHz, respectively is obtained in 3 × 3 array configuration. While optimizing on lossy thinner substrate, due to 3 × 3 array configuration, antenna yields broadside co-polar gain of nearly 2 dBi. In 1000MHz frequency band, the proposed configuration can find applications in wireless communication systems where transmitter and receiver antenna orientations are not important.

Ultra-wideband compact ring Sector printed monopole antenna

A novel compact ultra-wideband circular ring sector printed monopole antenna with decreasing Sectoral angle and modified feeding structure is proposed. A detailed parametric study for Sectoral angle decreasing from equivalent circular monopole patch to 330° ring Sector up till 60° ring Sectoral patch is presented. With decreasing angle ultra-wide band response with increasing lower frequency of the realized bandwidth is obtained in all the Sectoral patches. For Sectoral angle of 90°, an optimum response with offset feeding structure is realized. All the proposed Sectoral configurations yield bandwidth from less than 3 GHz to more than 10 GHz, thereby covering entire ultra-wide band frequency range. The proposed configurations yields gain of more than 1 to 2 dBi over the entire ultra-wide band frequency range.

Angular cut circular microstrip antenna for multi-band dual polarized response

Analysis and design of multi-band dual polarized circular microstrip antenna with an angular cut and pair of rectangular slot in 1000 MHz frequency range is proposed. The angular cut degenerates TM11 and TM21 resonant modes of equivalent circular patch into two orthogonal modes to yield multi-band response. Further pair of rectangular slots optimizes the input impedance at degenerated resonant modes and also modifies the surface current distribution at them to realize bandwidth of 1 to 2% with broadside radiation pattern at each of the frequencies. The suspended configurations of proposed dual polarized antenna is also optimized, which gives more than 4 dBi of gain at each of the frequencies.

Ultra-wideband star shaped planar monopole antenna

A novel design of ultra-wideband star shaped printed monopole antenna is proposed. A star shaped structure is realized by combining triangular shaped planar monopole patch with its inverted configuration. A detailed parametric study of the offset placement of two triangular shaped patches with respect to the patch centroids, variation in distance between the base of composite structure and the ground plane, is presented. To further improve impedance matching composite structure is chopped at the lower vertex point and a parametric study for the offset feed positions is carried out. The proposed antenna yields an optimum bandwidth of more than 8 GHz ranging from less than 2 GHz to more than 10 GHz with a broadside co-polar gain of around 1 to 2 dBi over a complete bandwidth.

Key-shaped slot loaded circular microstrip antenna for multi-band and broadband response

A novel design and analysis of circular microstrip antenna loaded with a key-shaped slot is presented. The introduction of key-shaped slot in the microstrip patch excites the additional modes which are orthogonal to each other, thus demonstrating multi-band dual polarized antenna characteristics. Also the next higher order modes manifest the broadband antenna response. For the optimization of the input impedance at the excited patch modes, a rectangular slot is incorporated in the patch design which realizes optimum bandwidth of 1 to 2% at each of the frequencies in 1000 MHz frequency range. The proposed dual-polarized antenna configuration yields broadside radiation pattern over all the resonant patch modes.