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This paper presents a novel dual-band dual-sense circularly polarized slot antenna design. The dual-band is achieved using a single-layer bended microstrip-fed configuration coupled to two slots. The dual-sense circularly polarization is obtained by an asymmetric slot-ring and L-shaped microstrip-fed in a wide square slot. Simulated results show that the proposed antenna has good circular polariza...Show More
This paper investigates an annular-ring slot antenna loaded by reactive components to generate dual-band dual-sense circular polarization. The antenna consists of two microstrip-line-fed and concentric annular-ring slots. Each annular-ring slot can obtain specific circularly polarized (CP) radiation through introducing an appropriate reactive component, i.e. distributed capacitor/inductor, at a pr...Show More
This paper discusses Different constitutive relations of generalized circular polarization in chiral media by using Maxwell's equations. In a chiral medium for fields with generalized circular polarizations, the Maxwell equations and constitutive relations have the same form in the achiral medium, but the equivalent material parameters differ for field with different circular polarization. Thus a ...Show More
This paper presents the design and realization of broadband and wide-beam right hand circularly polarized (RHCP) cross dipole antenna. The crossed dipole is backed by a conical shaped cavity to achieve improved axial ratio beam-width over a wide frequency band with enhanced gain. The design incorporates a conventional feeding technique using a coaxial probe. A sleeve is designed which is soldered ...Show More
In this paper, a compact omnidirectional circularly polarized (CP) cylindrical dielectric resonator antenna (DRA) is presented. The DRA is excited in its TM01δ mode by a probe located at the center, giving linearly polarized (LP) omnidirectional radiation patterns. Four interleaved strips serving as a wave polarizer are placed on the top of the DRA. By tuning the strips, the LP fields can be chang...Show More
A novel dual-band microstrip antenna with omnidirectional circularly polarized (CP) and unidirectional CP characteristic for each band is proposed in this communication. Function of dual-band dual-mode is realized based on loading with metamaterial structure. Since the fields of the fundamental modes are most concentrated on the fringe of the radiating patch, modifying the geometry of the radiatin...Show More
A wideband omnidirectional circularly polarized (CP) antenna is developed. The omnidirectional CP antenna includes four tilted dipoles that are wrapped around a cylinder for omnidirectional CP pattern. Each tilted dipole is coupled with a parasitic element for bandwidth enhancement. It is shown that the wideband omnidirectional CP antenna achieves an axial ratio (AR) bandwidth of 44% (1.69-2.64 GH...Show More
A dual circularly polarized (CP) patch antenna design with H-shaped aperture in S band is presented. The dual H-shaped slots are placed in orthogonal direction, and excited by the 3-dB branch-line coupler to obtain both right hand circular polarization (RHCP) and left hand circular polarization (LHCP). According to our simulation results, the proposed antenna element could achieve -10dB-level frac...Show More
In this letter, a wideband right-hand circularly polarized high-gain 4 × 4 microstrip patch array antenna on a polyethylene terephthalate (PET) film flexible substrate material is investigated. A comparison between the planar and curved surface study is also presented to show impact of curving the array on antenna performance parameters since it is employing a flexible substrate material. Due to s...Show More
This Matching polarization in both the transmitter and receiver antennas is important in terms of decreasing transmission losses. The use of circularly polarized antennas presents an attractive solution to achieve this polarization match which allows for more flexibility between transmitting and receiving antennas, reduces the effect of multipath reflections, enhances weather penetration and allow...Show More
A wideband circularly polarized antenna with a single feed is achieved by adjusting the shapes and dimensions of a linearly polarized magneto-electric (ME) dipole antenna. Experimentally, an antenna prototype operating at around 2 GHz exhibits a wide impedance bandwidth of 73.3% for SWR ≤ 2 and 46.6% for SWR ≤ 1.5, a 3-dB axial ratio bandwidth of 47.7% and an antenna gain of 6.8 ± 1.8 dBic. Based ...Show More
A wideband circularly polarized antenna with coaxial balun feed, using a broadband 90° hybrid feed network, is proposed. By introducing a narrow patch connecting the pair of bowtie dipoles as an entity that increases the effective radiation area, the proposed antenna delivers a higher gain than that of the conventional dual-fed-type circularly polarized antenna. It can achieve a measured impedance...Show More
A wideband circularly polarized (CP) antenna with a compact size of 0.64λ0×0.64λ0×0.27λ0 operating at the frequency of 2 GHz is presented. The antenna consists of a 4-way power divider, a patch antenna and a metasurface (MS). The input signal is fed to the 4-way power divider and the signals at the outputs of the 4-way power divider are coupled to a patch antenna using 4 orthogonally oriented L-sh...Show More
An omnidirectional circularly polarized (CP) antenna operating in W-band is proposed. The antenna has a simple structure, which consists of a dual-reflector antenna, an ortho-mode transducer (OMT) and a 3-dB coupler. The OMT adopts a novel septum-free structure, and can realize wideband, high isolation, and low loss. The results show that the dual-reflector antenna with this OMT has an impedance b...Show More
A dual-wideband dual-sense circularly polarized (CP) square slot antenna is presented in this paper. The righth- and circular polarization (RHCP) in +z direction for the lower frequency is mainly realized by an inverted L-shaped strip (ILSS). And the left-hand circular polarization (LHCP) in +z direction for the upper frequency is mainly achieved by an offset feed structure (OFS). The measured 10-...Show More
A novel wideband circularly polarized (CP) microstrip antenna with pattern improvement is proposed. Four vertical conductive walls surrounded with the radiation patch and four metal isosceles triangle patches located at top of the radiation patch are employed for widening beamwidth. To achieve the miniaturization of the antenna, four slots etched along the diagonals of radiation patch and the fold...Show More
This paper presents the design of a $\mathrm{4} \times \mathrm{4}$ elements circularly polarized microstrip patch array at millimeter-wave band. The sequential rotation method and series-parallel feed network are employed in the power distribution circuit for antenna performance improvement. The feed network is integrated on the same substrate layer of the antenna array in order to facilitate proc...Show More
A novel approach for highly miniaturizing a patch antenna with circular polarization is presented in this paper. It is shown that the antenna is fabricated by using an anisotropic conductor supporting the proper electric current paths and extreme miniaturization can be accomplished by manipulating its geometry. Anisotropic conductivity is achieved by removing strips of metal from the ordinary patc...Show More
A circularly polarized filtering transmitarray antenna (CPFTA) with a linearly polarized (LP) feed antenna is designed and implemented in this paper. An antenna-filter-antenna frequency selective surface (AFA FSS) has been designed and adopted as the transmitting layer of the proposed CPFTA. The designed AFA FSS has the multifunction of spatial filter, phase compensator and linearly polarized to c...Show More
This paper presents the design and development of an S-/C-band common aperture microstrip antenna. It features dual linear polarization (LP) at S-band and dual circularly polarized (CP) at C-band. The S-band element is proximity coupled to two orthogonal microstrip feeds. The C-band array is an aperture coupled to other two composite feeds which produce left-hand circular polarization (LHCP) and r...Show More
A new design of a dual-frequency dual circularly-polarized slot antenna is presented. The dual-frequency is achieved using a single-layer microstrip-fed configuration coupled to a modified annular-slot antenna. The dual sense circular-polarization is obtained by four unequal linear slots which augment the annular slot. Experimental results show the proposed antenna has good circular polarization c...Show More
In this paper, hexagonal substrate integrated waveguide (S IW) cavity is introduced to realize two low profile, single fe d and circularly polarized (CP) cavity antennas for the first time. One of the structures presents right handed CP (RHCP), while the other one offers left handed CP (LHCP). The two proposed antennas are compact and are light in weight. They can be easily fabricated using only a...Show More
This paper proposed an inband millimeter wave full duplex circularly polarized antenna. Multilayer structure and metasurface are employed. Left hand circularly polarization (LHCP) and right hand circularly polarization (RHCP) can be realized by exciting different ports. Slots and strip metal patches are used to improve isolation between ports. The simulated impedance bandwidth is 17%, ranging from...Show More
A millimeter-wave (mm-wave) circularly polarized (CP) antenna with wide axial-ratio (AR) beamwidth, consisting of L-shaped patches (LSPs) and a tapered elliptical cavity (TEC), is presented. The LSPs are fed by a transverse slot on the top metal surface of a substrate integrated waveguide, to excite two orthogonal modes in the cavity for CP radiation. Experimental results show that the proposed an...Show More
The rectangular-shaped metasurface (MTS)- based circularly polarized (CP) dual-port MIMO antenna was proposed. The proposed rectangular-shaped MTS-based CP dual-port MIMO antenna included two substrate layers (upper and lower). The periodic 4×4 rectangular-shaped MTS elements on the upper layer functioned as CP polarizers. Also, the lower substrate layer comprised the microstrip probe feed and gro...Show More