Bashir D. Bala

Bandwidth enhanced microstrip patch antenna using metamaterials

In this paper, a metamaterial antenna based on Split Ring Resonator (SRR) and a Thin Wire (TW) is proposed and studied. The proposed antenna consists of six unit cells and a thin wire of Left Handed Materials (LHM) arranged in 2×3 printed on same side of substrate. The TW stub of the unit cell is used to connect the LHMs to the radiating edge of a microstrip patch antenna. The constitutive parameter of the LHM is retrieve to reveal the left handed region. By using these techniques, the bandwidth of the metamaterial antenna is twice that of the ordinary patch antenna at the same operating frequency.

Design and analysis of metamaterial antenna using Triangular resonator

In this paper, a metamaterial antenna consisting of Triangular resonator (TR) and a thin wire (TW) is proposed. The antenna is excited through a single unit cell left Handed Materials (LHM) which act as the main radiating element via coplanar waveguide (CPW) transmission line. The Left Handedness of the unit cell is investigated and verified. The simulated return loss shows that a bandwidth of 58% is achieved over a frequency band of 6.42-11.23 GHz at a return loss of -10dB. The maximum gain of 4.45 is obtained at a frequency of 10.32GHz. Simulated and measured return loss shows an agreement while the radiation pattern is Omnidirectional.

Wideband metamaterial antenna employing SRR loading for WiMAX and WLAN operations

A wideband metamaterial antenna employing SRR loading is presented. Two designs were simulated, fabricated and measured. The bandwidth enhancement is achieved by loading SRR resonator onto a conventional monopole antenna. The SRR excited a lower resonance frequency mode which matches with the resonance frequency of the monopole antenna thereby extending the overall impedance bandwidth from 26% to 91%. The antenna has a compact size of 30 × 26 mm2. The peak realized gain and efficiency of 3.2 dB and 76% are obtained respectively. The antenna has potential applications for WLAN and WiMAX operations.

An epsilon negative metamaterial antenna with extended bandwidth

In this paper, a design and simulation study of a new epsilon-negative metamaterial antenna consisting of a squared shaped complementary split ring resonator (CSRR), shorting via and a stub is presented. The antenna resonates at 2.95 GHz with impedance bandwidth of 17.5%. The overall size of the antenna is 0.36λ_o × 0.33λ_o with the size of the main antenna radiating element of 0.15λ_o × 0.15λ_o at 2.95 GHz. A prototype has been fabricated and tested to validate the design. Peak realized gain of 2.19 dBi is obtained at resonance frequency. Simulated and measured results are presented and compared.

Analysis of triple band artificial magnetic conductor (AMC) band conditions to wideband antenna performance

This paper presents the design of wideband antenna integrated with triple band artificial magnetic conductor (AMC) ground plane. The wideband antenna that acts as Reference Antenna (RA) operates from 2.69 GHz up to 6.27 GHz while the triple band AMC operates at 2.3 GHz, 5.8 GHz and 8.3 GHz. The investigation is carried out to observe the capability of triple band AMC to excite at least three new narrowband resonances which are in band (IB), slightly out Of band (SOB) and totally out of band (TOB) with respect to the bandwidth of RA. The antennas performance parameter such as return loss, gain variation, and radiation pattern are presented.

Dual band metamaterial antenna with loaded resonators

In this paper, a dual band metamaterial antenna is presented. The antenna consists of complementary split ring resonator (CSRR), slotted capacitor loaded strip (SCLS) and a via. The CSRR and SCLS enable the resonance frequency at 5.33 GHz and 2.39 GHz respectively for the dual band operation. The overall size of the antenna is 0.53λo × 0.52λo × 0.023λo (36 mm × 35 mm × 1.52 mm) at 2.39 GHz. The peak realized gains of 4.17 dBi and 2.2 dBi are obtained at 5.33 GHz and 2.39 GHz respectively. Simulated and measured reflection coefficient are presented and discussed.

Dual band stacked artificial magnetic conductor with dipole antenna

This paper proposed a design of dual substrate layer Artificial Magnetic Conductor (AMC) which operates at operating frequency of 2.45 and 5.8 GHz. The top circular ring and the bottom rectangular AMC patch correspond to higher and lower frequency respectively. The offset effect due to distance and angular variations on the reflection phase has also been studied. The study further extended to the effect of double and quadruple circular ring AMC on the top substrate layer of stacked AMC. The dual band stacked AMC is then integrated onto two dipole antennas operating at 2.45 and 5.8 GHz band. The performance of antenna with and without AMC is observed in terms of reflection coefficient, directivity and radiation patterns.

Dual band dielectric resonator based metamaterial antenna

A dielectric resonator based metamaterial antenna is presented for dual band operations. The hybrid design uses the dielectric resonator (DR) and split ring resonator (SRR) to radiate two resonant modes. The antenna has a compact size of 40 × 40 mm2. The peak realized gain of 6.24 dBi and 6.04 dBi is obtained at 5.5 GHz and 5.8 GHz respectively. Also a peak efficiency of 94% is obtained across the covering frequency. The antenna has potential applications for WiMAX (5.5 GHz) and WLAN (5.8 GHz) operations.

Reconfigurable epsilon negative metamaterial antenna

In this paper, frequency reconfiguration is implemented on an epsilon negative metamaterial (ENG-MTM) antenna. Switching on/off the MTM unit cells via the inductive stubs reconfigures the resonance frequency. Copper strips are use as switches. In effect, the antenna can be reconfigured from narrow to wideband and the zero order resonance (ZOR) frequency can also be reconfigured from 1.9 GHz to 2.6 GHz with reflection coefficient of -16.97dB and -21.5dB respectively and total efficiency of 0.914dB. The antenna has potential application for cognitive radio system.

A compact microstrip patch antenna for ADS-B operation

A compact microstrip patch antenna for Automatic dependence surveillance system (ADS-B) is presented. The antenna is fed by a 50Ω transmission line. T-slot is etched on the ground plane to achieve some degree of miniaturization of the design. The proposed antenna has a compact size of 82 mm × 65 mm with electrical size of 0.297λ0 × 0.23λ0 at 1.09 GHz. The antenna resonates at 1.09 GHz typical for ADS-B applications. The predicted gain of the ADS-B antenna is from 1dB to 5dB whereas the measured gain is about 3.10dB. It is anticipated that the proposed antenna can fulfill the ADS-B specifications. The design is validated by fabrication and measurement of the prototype. Simulated and measured results are obtained and compared.