Compact Planar Monopole Antenna Research Articles

Axial ratio bandwidth improvement of compact planar monopole antenna with dual‐band and dual‐sense

SummaryA small size, dual‐band and dual‐sense monopole antenna is proposed to improve the axial ratio bandwidth (ARBW). The proposed antenna is considered on a low‐cost lossy FR4 substrate with parasitic strips (PSs) and partial ground plane of half guided wavelength dimensions. The dimension of the antenna in terms of wavelength is , where is the wavelength at the lowest resonant frequency. The circularly polarized (CP) mode is created for strong orthogonal electric fields and . The obtained phase difference (PD) between two electric fields and is varied from to under ARBW. The achieved ARBW is 3.68–3.8 GHz, 4.84–12.58 GHz, and impedance bandwidth (IBW) is 3.51–3.82 GHz and 4.28–15 GHz. The applications of the proposed antenna are International Telecommunication Union (ITU) for 5G, C‐band IEEE 802.11a wireless local area network (WLAN) at 5 GHz (5.15–5.825 GHz) and X‐band wireless systems.

Ultra Wideband Planar Monopole Antenna with Pair of C-Shaped Slots and T-Shaped Sleeve for Microwave Systems

This paper introduces a compact UWB planar monopole antenna for microwave imaging systems. An antenna consists of square shaped radiating patch with a couple of C shaped slots for exciting resonance. By introducing T shaped sleeves on the ground plane, wide impedance bandwidth is achieved in range of (3.6 - 12 GHz). The proposed antenna has compressed size having dimensions Ls× Ws× Hs mm3. By embedding C-shaped slots with varying dimensions on radiating patch additional resonance are excited which results better wide impedance bandwidth. Simulated results such as return loss, gain, radiation pattern authenticate the convenient antenna structure for different microwave imaging system applications.

Novel Compact UWB Planar Monopole Antenna Using a Ribbon-Shaped Slot

Ultra-Wideband (UWB) is a wireless communication technology that can be utilized for precise indoor positioning system. UWB is low power-consuming and resistant to complex multipath environments, thanks to a short pulse signal. Since the main desired characteristics of the UWB antennas for radio-frequency localization systems are wide bandwidth, omnidirectional radiation pattern, and low profile for simple integration with printed circuit boards, various planar monopole antennas for UWB applications were proposed to meet the requirements. In order to satisfy these conditions, in this paper, a novel compact UWB planar monopole antenna operating in 3.1 GHz – 10.8 GHz is designed on FR-4 substrate. The overall size of the antenna is 12.5 × 12.5 × 1 mm³, which is 0.129 λ₀ × 0.258 λ₀ × 0.01 λ₀ in free space at the lowest frequency. The transmission line is designed based on a coplanar waveguide with ground (CPWG) and vias in the CPWG are employed to eliminate non-radiating phenomenon at some specific frequencies. The shape of the radiator is modified from the hexagonal shape and a ribbon-shaped slot inside the radiator is adapted to improve the operating frequency range. The proposed UWB planar monopole antenna is fabricated and measured. The proposed antenna provides good antenna performance from 3.1 to 10.8 GHz and also the radiation patterns at various frequencies are omnidirectional pattern.

Ultra-wideband Flexible Implantable Antenna for Wireless Capsule Endoscopy System with Performance Improvement

The implantable antenna is an important part of the wireless capsule endoscopy (WCE) system to achieve wireless communication. This paper designed an ultra-wideband flexible implantable antenna for wireless capsule endoscopy system. With a very wide bandwidth, the antenna can completely cover the industrial, scientific, and medical frequency bands (ISM, 2.4-2.48 GHz) and Wireless Medical Telemetry Service (WMTS, 1.395-1.4 GHz). The expanded size of the proposed antenna is 18mm× 10mm× 0.1mm. The conformal technology of the antenna has further reduced the space of the system and achieved miniaturization. The capsule antenna in this paper is a compact planar monopole antenna fed by a coplanar waveguide, and it uses a flexible material as a dielectric substrate to achieve the conformal shape of the antenna. U-shaped ground branch (UGB) and a loaded split ring resonator (SRR) structure were used to further improve the antenna performance. Simulation and measurement results were basically the same. On the premise of radiation safety and miniaturization of the antenna, the ultra-wideband operation of the antenna was realized. This antenna design provided reference value for the design and application of the capsule antenna.

Optically Controlled Superwideband to Multiband Reconfigurable Antenna for Wireless Applications

Aim: Design of a reconfigurable microstrip planar antenna for wireless applications. Objective: To design an optically controlled microstrip planar antenna with superwideband (SWB) to multiband reconfigurable characteristics without using any biasing network. Methods: The use of a photoconductive switch made of Cadmium Sulphide (CDS) based semiconductor is conceived to realize the optically controlled reconfigurable antenna. The operating characteristics of the proposed antenna have been changed between SWB to multiband when the CDS coating is illuminated by the light-emitting diode. Results: Under the switch-off condition, SWB of 167% (1.8-20 GHz), fractional bandwidth with higher Bandwidth to Dimension Ratio (BDR) and a bandwidth ratio of 11.11:1 are achieved. While for the switch-on condition, triple-band (1.8-3.9 GHz, 4.3-7.3 GHz, and 8.2-15.4 GHz) operation with the resonating frequency of 3.4GHz, and 5.5GHz and, 12GHz covering the useful WiMAX, and WLAN wireless bands have been achieved with the realized peak gain of 2.34dBi, 4.18dBi, and 3.08dBi, respectively. Conclusion: An optically switchable SWB to triple-band compact planar monopole antenna has been analyzed and presented based on the simulation results. This design is reasonably compact and provides better BDR than the reported antennas of its class. The proposed design is flexible enough to adjust the operating bands by varying the dimensions of the defected ground structure (DGS) and stub. This antenna with switching ability can fulfill the requirement of the antenna society for wireless applications.

A Phase Angle-Modulated Bat Algorithm with Application to Antenna Topology Optimization

This paper proposes a phase angle-modulated bat algorithm (P-AMBA) for high-dimensional binary optimization. The idea was to reduce the optimization time by introducing angle modulation technology to reduce the optimization dimensions. Different from the original angle-modulated bat algorithm (AMBA), the control of the trigonometric generating function cosine wave is by introducing new parameters, thereby improving the perturbation ability of the function curve near the x-axis. P-AMBA can explore more 0/1 solutions, and it has advantages in optimizing convergence speed and global search capabilities. The numerical results of the 0–1 knapsack problem tests show that P-AMBA is superior to the contrast algorithms on optimization ability and optimization time. Finally, the experimental result of a compact dual-band planar monopole antenna design showed the effectiveness of P-AMBA in engineering applications.

Dual‐band dual‐polarized compact planar monopole antenna for wide axial ratio bandwidth application

In this article, a geometrically simple, microstrip line-fed planar monopole structure with slanting edge ground plane is designed to realize the dual-band dual-polarized operation. The proposed antenna consists of a rotated U-shaped patch and an electromagnetically coupled L-shaped parasitic radiating element. Owing to the combination of microstrip line-fed radiating patch and a slanting-edge rectangular ground plane on the opposite side of the substrate, the proposed dual-band antenna can generate broad axial ratio bandwidth (ARBW) in the upper frequency band. The overall dimension of the prototype is only 32 × 32 × 1.6 mm3. The measured results validate that the proposed antenna has two operational frequency bands, 29.84% (1.54-2.08 GHz) for linearly polarized radiation and 71.85% (3.96-8.4 GHz) for circularly polarized radiation. Measured result shows that 3-dB ARBW of the proposed antenna is 73.54% (3.80-8.22 GHz) in the higher frequency band. It shows that the higher frequency band exhibits a left-hand circularly polarized radiation in the boresight direction.

A Metamaterial-Based Compact Planar Monopole Antenna for Wi-Fi and UWB Applications.

Ultrawideband (UWB) antennas are widely used as core devices in high-speed wireless communication. A novel compact UWB monopole antenna with an additional narrow band for Wi-Fi applications comprising a metamaterial (MTM) is proposed in this paper. The antenna has a compact size of 27 × 33 mm2 and consists of a V-shaped slot with two rectangular slots in the radiation patch. The inductance and capacitance develop due to the V-shaped slot in the radiation patch. The proposed antenna has −10 dB bandwidths of 3.2 GHz to 14 GHz for UWB and 2.38 GHz to 2.57 GHz for narrowband, corresponding to 144% and 7.66% fractional bandwidths, respectively. The measured gain and efficiency meet the desired values for UWB and Wi-Fi applications. To verify the performance of the antenna, the proposed antenna is fabricated and tested. The simulated and measured results agree well at UWB frequencies and Wi-Fi frequencies, and the antenna can be used as a smart device for portable IoT applications.

Design and acceptance test of compact planar monopole antenna for LTE smartphone considering SAR, TRP, and HAC values

SummaryEight different types of compact multiband planar antennas are proposed in this work for covering several long‐term evaluation (LTE) and Wi‐Fi bands in a smartphone antenna design. Gradual inclusion of several sections of a radiator on an inexpensive FR4 substrate is presented for receiving multi‐LTE bands with a handset device. Along with the presently available LTE bands, this antenna design approach also includes upcoming LTE in unlicensed spectrum and LTE licensed‐assisted access. Various techniques such as partial ground, branch line slit, parasitic structure, and meandered lines are used to achieve desired resonant frequencies, bandwidth, matching, and miniaturization. The final type of eight antennas has been implemented in the real‐world mobile phone handset. The interaction between the mobile handset and the human phantom model has been analyzed at few specific frequencies for evaluating specific absorption rate (SAR) and total radiated power (TRP) in a simulated manner. The same type is also studied as a hearing aid compatibility (HAC)–supported wireless device. The simulated results show the SAR and HAC values are at the acceptance level for this proposed design. A prototype model is developed and few parameters are measured for validation.

Compact ultra-wideband circularly polarized CPW-fed monopole antenna

This paper presents a coplanar waveguide (CPW) -fed quadrilateral-shaped compact planar monopole antenna for ultra-wideband (UWB) application. The fractional axial ratio bandwidth (ARBW) of the antenna for circular polarization (CP) is 56.64% (5.91–10.58 GHz) and its fractional impedance matching bandwidth (IMBW) is 137.1% (3.1–17.5 GHz), which are realized by designing a quadrilateral-shaped monopole with an asymmetric ground plane. The proposed antenna structure is simple and compact; hence its design is efficient, and it has an impedance matching (S11) in UWB band with embedded wideband circular polarization. The gain of the antenna varies between 3.33 and 8.9 dBi. Furthermore, its application for designing the linear array and planar array of 1 × 2 and 2 × 2 antenna elements are presented. The gain improves to 5.1–9 dBi for 1 × 2 array elements and to 9–11.2 dBi for 2 × 2 array with UWB IMBW. Simulated and experimental results are presented to validate the antenna design and are shown to be in good agreement.

Design, Fabrication and Measurement of a Novel Compact Triband CPW-Fed Planar Monopole Antenna Using Multi-type Slots for Wireless Communication Applications

A novel compact coplanar waveguide (CPW)-fed planar monopole antenna with triple-band operation is presented for simultaneously satisfying the LTE 2600, WiMAX, WLAN and X-band applications. It is printed on a single-layered FR4 substrate. In this paper, the proposed antenna, which occupies a small volume of [Formula: see text][Formula: see text]mm3 including the ground plane, is simply composed of a CPW-fed monopole with U-, L- and T-shaped slots. By carefully selecting the lengths and positions of both L-shaped and U-shaped slots, a good dual notched band characteristic at center-rejected frequencies of 3.10[Formula: see text]GHz and 4.50[Formula: see text]GHz can be achieved, respectively. The T-shaped slot is etched on the radiating element to excite a resonant frequency in the 7[Formula: see text]GHz band. Then, to prove the validation of the typical design, a prototype model is fabricated and measured. The experimental result shows that the three frequency bands of 2.31–2.80[Formula: see text]GHz (490[Formula: see text]MHz), 3.37–3.84[Formula: see text]GHz (470[Formula: see text]MHz) and 5.04–7.94[Formula: see text]GHz (2900[Formula: see text]MHz) can successfully cover the desired bandwidths of LTE2600/WiMAX (3.50/5.50[Formula: see text]GHz)/WLAN (5.20/5.80[Formula: see text]GHz) and the X-band communication systems (7.1-GHz operation). The principal applications of the X-band are radar, aircraft, spacecraft and mobile or satellite communication system. Nearly omnidirectional and bidirectional radiation patterns of the triband antenna are observed in both H- and E-planes, respectively. In addition, a reasonable gain over the operating bands has been obtained. Indeed, the good agreements between simulation and measurement results have validated the proposed structure, confirming its potential for multiband wireless communication services.

Compact multiband planar monopole antenna for Bluetooth, LTE, and reconfigurable UWB applications including X‐band and Ku‐band wireless communications

In this article, a small-printed Bluetooth/LTE/UWB/X-band/Ku-band monopole antenna with high rejection triple band-notch is presented. Notched bands include WiMAX (IEEE802.16 3.30-3.80 GHz), WLAN IEEE802.11a/h/j/n (5.15-5.35 GHz, 5.25-5.35 GHz, 5.47-5.725 GHz, and 5.725-5.825 GHz), and downlink satellite system (7.1-7.9 GHz). By including inverted T-shaped stub and etching two C-shaped slots on the radiating patch, triple band-notch function is obtained with measured high band rejection (VSWR = 14.59 at 3.69 GHz, VSWR = 39.40 at 5.42 GHz, and VSWR = 6.43 at 7.57 GHz) and covers a UWB useable fractional bandwidth of 157.75% (2.285-19.35 GHz = 17.065 GHz). Reconfigurable characteristics are obtained using PIN diodes, which control the individual notched bands. Proposed antenna is printed on Rogers RT/duroid5880 substrate with compact dimensions of 20 × 22 mm2. Proposed antenna finds its applications for Bluetooth, LTE, UWB, other multiple wireless applications for close range radar (8-12 GHz) in X-band, and satellite communication in Ku-Band with omnidirectional pattern in H-plane.

A Compact CPW-Fed Dual-Band Planar Monopole Antenna for LTE/2.4-GHz/WiMAX, C-Band and HiperLAN/2 Applications

In this paper, we present the design of a compact planar monopole antenna for dual-band wireless communication applications. The proposed antenna is based on a planar structure composed by a CPW feed line and a rectangular ring with a vertical strip. The designed antenna has a small overall size of [Formula: see text][Formula: see text]mm3. Dual-band characteristics can be obtained by adjusting the distance between the rectangular ring and the ground plane of the CPW feed line, as well as the dimensions of the rectangular ring and the length of the vertical strip. A prototype of the proposed antenna which was fabricated and measured to validate the design reveals that there is a good agreement between the simulation and the experiment. The measured result shows that the antenna has the impedance bandwidths of 610[Formula: see text]MHz (2–2.61[Formula: see text]GHz) and 2600[Formula: see text]MHz (3.18–5.78[Formula: see text]GHz) with a reflection coefficient less than [Formula: see text]10[Formula: see text]dB covering all the LTE 2300, 2.4-GHz band, WiMAX, C-band and HiperLAN/2 applications. In addition, the dual-band monopole antenna exhibits almost omnidirectional radiation patterns and an appreciable gain over the operating frequency bands. Details of the proposed antenna design and both simulated and experimental results are analyzed and discussed.

Unidirectional Planar Monopole Antenna Using a Quasi-Radiator

A compact wideband planar monopole antenna with unidirectional radiation properties is proposed in this letter. The measured results demonstrate that the antenna has an S 11 F / B ) > 10 dB across the operating frequency range. The antenna is very simple, comprising a slotted-stepped radiating patch attached to the ground plane through a shorting side stub. The antenna has a small size of 20 × 20 mm2, good F / B , and does not require cavity-backed structures and ground plane extensions, making it attractive for compact wireless devices. The antenna also possesses stable main lobe directions.

Miniaturized CPW-Fed Planar Monopole Antenna for Multi-band WLAN/WiMAX Wireless Applications

To incorporate two different communication standards in a single device, a miniaturized dual-band planar monopole antenna is presented in this paper. The proposed antenna is formed by a CPW feed line and a rectangular ring monopole with a vertical strip. The designed antenna has a small overall size of 19 mm Ž 36 mm Ž 1.6 mm. A prototype of the proposed antenna which was fabricated and measured to validate the design shows a good agreement between the simulation and the experiment. The measured results indicate that the antenna has the impedance bandwidths of 650 MHz (2.30-2.95 GHz) and 2460 MHz (3.40-5.86 GHz) at the first and second bands, respectively with a reflection coefficient less than - 10 dB covering all the WLAN bands (2.4/5.2/5.8 GHz) and WiMAX bands (2.6/3.5/5.5 GHz). In addition, the nearly omni-directional and bi-directional radiation patterns are also achieved in both H- and E-planes, respectively. It is also noticeable that a good antenna gain over both operating bands has been obtained. There- fore, this simple compact planar monopole antenna with multi-band characteristics is well suitable for WLAN and WiMAX wireless communication applications. Details of the proposed antenna design and both simulated and experimental results are analyzed and discussed.

Double-ring multiband microstrip patch antenna with parasitic strip structure for heterogeneous wireless communication systems

In this paper, a novel design of compact Coplanar Waveguide-fed planar monopole antenna with enhanced bandwidth and multiband characteristics has been proposed. Two rectangular rings have been incorporated in a rectangular patch to obtain multiband operation for Wireless Local Area Network (WLAN) (2.4/5.2/5.8 GHz) and Worldwide Interoperability for Microwave Access (WiMAX) (2.3/2.5/5.5 GHz) bands. A parasitic strip and meandering along with double-ringed structure have been used to achieve enhanced impedance bandwidth in WLAN (from 2.26 to 3.03 GHz) and WiMAX (from 4.48 to 6.85 GHz) bands. The parametric analysis is carried out to study effect of varying dimensions on antenna performance. The proposed antenna is optimized and prototype is designed and fabricated. Simulated and measured radiation patterns in elevation and azimuthal planes are also observed. The antenna shows significant gain of 7.33 dBi at 6.54 GHz frequency.

Compact multi‐band novel‐shaped planar monopole antenna for DCS, Bluetooth, and ultra‐wide‐band applications

In this study, simple and compact novel-shape planar monopole antenna for multi-band operation such as DCS, Bluetooth, and ultra-wide-band (UWB) is proposed. Proposed antenna comprises of circular ring with extended rectangular monopole antenna in one of the arm of the circular ring and inverted L-shape monopole antenna at the centre of the structure is placed to generate multiple resonances at different frequencies. In this structure, Bluetooth frequency band generates due to extended rectangular patch, DCS band by inverted L-patch, and UWB bands due to circular ring. Easily available FR4 substrate with permittivity 4.4 and loss tangent 0.02 is used for fabrication with antenna dimensions (35.5 × 24.5 × 1.6) mm3. Antenna structure is fed through 50 Ω micro-strip line and terminated by SMA connector. Measured return loss of the antenna is ≤−10 dB with effective control over the three operating frequency bands. In addition, some selected key parameters which affect the impedance bandwidth are analysed and results are discussed.

Design of a uniplanar printed triple band‐rejected ultra‐wideband antenna using particle swarm optimisation and the firefly algorithm

A compact planar monopole antenna is proposed for ultra-wideband applications. The antenna has a microstrip line feed and band-rejected characteristics and consists of a ring patch and a partial ground plane with a defective ground structure of rectangular shape. An annular strip is etched above the radiating element and two slots, one C-shaped and one arc-shaped, are embedded in the radiating patch. The proposed antenna has been optimised using bio-inspired algorithms such as the particle swarm optimisation and the firefly algorithm, based on a new software algorithm (Antenna Optimizer). Multi-objective optimisation achieves rejection bands at 3.3-3.7 GHz for Worldwide Interoperability for Microwave Access, 5.15-5.825 GHz for the 802.11a wireless local area network system or HIPERLAN/2, and 7.25-7.745 GHz for C-band satellite communication systems. Validated results show wideband performance from 2.7 to 10.6 GHz with S 11 <; -10 dB. The antenna has compact dimensions of 28 × 30 mm 2 . The radiation pattern is comparatively stable across the operating band with a relatively stable gain except in the notched bands.

COMPACT TRI-BAND DUAL-POLARIZED PLANAR MONOPOLE ANTENNA WITH ASYMMETRICAL GROUND PLANE AND LOADED STUB

This paper presents a compact tri-band dual-polarized planar monopole antenna, which is linearly polarized in the lower and middle bands and circularly polarized in the higher band. The antenna is printed on a substrate with an asymmetrical ground plane and a loaded vertical stub. The vertical stub and asymmetrical ground plane are mainly used to make the antenna obtain circular polarization performance in the higher band. The antenna has been built and tested. Its measured 10-dB impedance bandwidths are 2.39-2.54 GHz, 3.38-4.12 GHz, and 4.57-6.04 GHz, which can fully cover all the 2.4/5.2/5.8 GHz WLAN bands, all the 2.4/5.5 GHz Wi-Fi bands, and 3.5/5.5 GHz WiMAX bands. In the higher band, the measured 3-dB axial-ratio bandwidth is 5.4-5.83 GHz.

Planar Dual-Band Monopole Antenna with an Extended Ground Plane for WLAN Applications

A compact planar microstrip-fed monopole antenna designed for dual-band operation is proposed for WLAN applications. The antenna is composed of a rectangular strip monopole in addition to an inverted-L parasitic element that is connected to the truncated ground plane of the microstrip feed. Besides exciting an additional band of operation, the parasitic element also improves the bandwidth of the band excited by the strip monopole. Several simulated parametric studies are conducted to investigate the effects of each geometrical parameter on the behavior of the antenna. Experimental and simulation results demonstrate that the proposed antenna covers the 2.4 and 5.8 GHz bands utilized in WLAN. In both bands, the proposed antenna exhibits good impedance match, moderate gain (approximately 2 dBi), and sustainable omnidirectional-like radiation patterns in both principal planes. An equivalent circuit model of the antenna is also developed.