Showing papers on "Folded inverted conformal antenna published in 2014"
TL;DR: An implantable rectenna, which consists of a planar inverted-F antenna (PIFA) and a rectifier circuit, is proposed for far-field wireless power transfer and a method of adding a parasitic patch over the human body is used to enhance the wireless power link.
Abstract: An implantable rectenna, which consists of a planar inverted-F antenna (PIFA) and a rectifier circuit, is proposed for far-field wireless power transfer. The PIFA has a folded ground plane to miniaturize its size. The performance of the wireless power link between the implanted antenna and an external antenna is examined. A method of adding a parasitic patch over the human body is used to enhance the wireless power link, thus to increase the received power level. Safety considerations of far-field RF powering are discussed. The RF-to-DC conversion circuit efficiency is optimized after the receiver power level of the implantable antenna is estimated based on the safety considerations. Finally, a rectifier circuit and an integrated rectenna solution are discussed.
175 citations
Patent•
17 Feb 2014
TL;DR: In this article, a multiband common-caliber antenna with a continuous transverse stub (CTS) antenna and a microstrip patch antenna is presented. But the CTS antenna does not have an antenna array array array.
Abstract: An embodiment of the present invention provides a multiband common-caliber antenna. The multiband common-caliber antenna of the present invention comprises a continuous transverse stub (CTS) antenna and a microstrip patch antenna. The CTS antenna comprises a planar waveguide feeding structure and multiple strip-shaped waveguide radiation units disposed on the planar waveguide feeding structure and disposed in a spaced manner along a first direction. A medium substrate is disposed between every two strip-shaped waveguide radiation units and on the upper surface of the planar waveguide feeding structure. Microstrip patch antenna arrays are disposed on the upper surface of the medium substrate. Each of the microstrip patch antenna arrays comprises multiple microstrip patch antenna units disposed in a spaced manner along a second direction perpendicular to the first direction. The number of the microstrip patch antenna arrays disposed on at least one of the medium substrate is not less than 2. The microstrip patch antenna arrays disposed on the medium substrates form the microstrip patch antenna. The embodiment of the present invention suppresses mutual coupling between surface waves of the microstrip patch antenna and the antenna.
137 citations
TL;DR: In this article, a wideband compact circularly polarized (CP) patch antenna is proposed, which consists of a printed meandering probe (M-probe) and truncated patches that excite orthogonal resonant modes to generate wideband CP operation.
Abstract: In this letter, a wideband compact circularly polarized (CP) patch antenna is proposed. This patch antenna consists of a printed meandering probe (M-probe) and truncated patches that excite orthogonal resonant modes to generate a wideband CP operation. The stacked patch is employed to further improve the axial-ratio (AR) bandwidth to fit the 5G Wi-Fi application. The proposed antenna achieves 42.3% impedance bandwidth and 16.8% AR bandwidth, respectively. The average gain within the AR bandwidth is 6.6 dBic with less than 0.5 dB variation. This work demonstrates a bandwidth broadening technique of an M-probe fed CP patch antenna. It is the first study to investigate and exhibit the M-probe could also provide the wideband characteristics in the dielectric loaded patch antenna. The potential applications of the antenna are 5G Wi-Fi and satellite communication systems.
104 citations
TL;DR: In this article, a center-fed circular patch antenna with shorting vias and a coupled annular ring is proposed to provide a wide bandwidth by merging three resonant modes.
Abstract: A center-fed circular patch antenna with shorting vias and a coupled annular ring is proposed. With a low-profile configuration, the antenna provides a wide bandwidth by merging three resonant modes, including the TM02 mode of the circular patch, the TM01 mode generated by the shorting vias, and the TM02 mode of the coupled annular ring. The antenna operating in these modes would produce an omnidirectional pattern in the horizontal plane similar to that generated by a monopole antenna. A reduced structure is used to simplify the simulation in optimizing the bandwidth of the antenna. Measured results show that the antenna achieves a bandwidth of 27.4% for a profile of 0.029 wavelengths and has a gain of about 6 dBi.
96 citations
TL;DR: In this article, a coplanar waveguide-fed transparent antenna for ultrawideband applications with enhanced bandwidth is presented, where different techniques have been used to broaden the bandwidth.
Abstract: A novel coplanar waveguide-fed transparent antenna for ultrawideband applications with enhanced bandwidth is presented. In this design, different techniques have been used to broaden the bandwidth. The rectangular radiator of the antenna is equipped by the staircase technique to increase the overlapped resonant frequencies. Moreover, two major and minor symmetrical rectangular stubs are mounted on top of the quarter-circle slot ground by using a dual axis to significantly increase the bandwidth between 3.15 and 32 GHz for VSWR <; 2. AghT-8 transparent thin film is used in the design of the proposed antenna to obtain a very compact size and lightweight structure.
85 citations
TL;DR: Study demonstrate that the proposed antenna is a good candidate for ultra-high-frequency RFID tags to be mounted on metallic surfaces, especially in size-constrained scenarios, and a figure of merit, namely, NBG, is presented, with which a comparison among electrically small tag antennas is carried out.
Abstract: A novel dual-layer electrically small radio-frequency-identification (RFID) tag antenna is proposed for metallic object applications. With a proximity-coupled feed method, two rotationally symmetric loaded via-patches are fed through an embedded dual-element planar inverted-F antenna (PIFA) array. With this configuration, the antenna volume is reduced to 0.08 λ×0.04 λ×0.007 λ while the measured antenna gain is 0.08 dBi at the frequency of 923 MHz. Studies demonstrate that the proposed antenna is a good candidate for ultra-high-frequency RFID tags to be mounted on metallic surfaces, especially in size-constrained scenarios. Meanwhile, a figure of merit, namely, NBG, is presented, with which a comparison among electrically small tag antennas is carried out. Finally, several guidelines are given out to facilitate the miniaturization of RFID tag antennas for metallic object applications.
83 citations
TL;DR: In this paper, a defected ground structure (DGS) was employed to shift the resonance frequency of an initial microstrip antenna from 5.7 GHz to 3 GHz by disturbing the antenna's current distribution.
Abstract: The aim of this work is to miniaturize a microstrip patch antenna resonating at 3 GHz. For this purpose, defected ground structure (DGS) has been employed to shift the resonance frequency of an initial microstrip antenna from 5.7 GHz to 3 GHz by disturbing the antenna's current distribution. The proposed DGS is incorporated in the ground plane under the patch antenna to improve its performances. Finally, a miniaturization up to 50%, with respect to the conventional microstrip antenna, is successfully accomplished. A prototype of the antenna was fabricated with the FR4 substrate and tested. The measurements results were in good agreement with simulation results.
83 citations
TL;DR: In this article, a planar dual-band phased array with wide-angle scanning capability is presented, where a new single-layer crossed L-bar microstrip antenna is used for the array design.
Abstract: A novel planar dual-band phased array, operational in the X/Ku-bands and with wide-angle scanning capability is presented. The design, development and experimental demonstration are described. A new single-layer crossed L-bar microstrip antenna is used for the array design. The antenna has low-profile architecture, measuring only $0.33\lambda \times 0.33\lambda $ , at the low frequency band of operation, with flexible resonance tuning capability offered by the use of a plate-through-hole and field-matching ring arrangement. A 49-element planar (7 $\,\times \,$ 7) array demonstrator has been built and its performance validated, exhibiting good agreement with full-wave simulations. The dual-band array supports a large frequency ratio of nearly 1.8:1, and also maintains good sub-band bandwidths. Wide-angle scanning up to a maximum of 60 $^{\circ}$ and 50 $^{\circ}$ are achieved at the low and high frequency bands of operation, respectively.
82 citations
TL;DR: In this article, a planar source-fed folded reflectarray antenna (FRA) with low profile is proposed to achieve high gain for Q-band millimeter wave high data rate wireless communication applications.
Abstract: An integrated design of a planar source-fed folded reflectarray antenna (FRA) with low profile is proposed to achieve high gain for Q-band millimeter wave high data rate wireless communication applications. A planar substrate integrated waveguide (SIW) slot array antenna is adopted as the primary source to illuminate the proposed FRA. Considerations of the off-focus loss and the asymmetry E- and H-plane beamwidths loss of the planar source are thoroughly investigated to improve the aperture efficiency of the reflectarray antenna. A prototype is implemented and the experimental results are in good agreement with the predictions, which exhibit a measured |S
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| less than -10 dB over the frequency band of 41.6-44 GHz, a maximum boresight gain of 31.9 dBi at 44 GHz with the aperture efficiency of 49% and a -3 dB gain drop bandwidth of 41.8-44.9 GHz. By integrating with the planar feed, the proposed folded reflectarray antenna benefits from its low-profile, low cost, and the ability of coplanar integration with millimeter wave planar circuits while maintaining the good performance in terms of gain and efficiency.
75 citations
TL;DR: In this article, a compact frequency-reconfigurable multiple-input-multiple-output (MIMO) antenna on a laptop is proposed for multiband LTE services, which consists of two planar inverted-F antenna (PIFA) elements, using a T-shaped dc line and two p-i-n diodes (D1 and D2), in conjunction with the proximity-coupled feed structure.
Abstract: A compact frequency-reconfigurable multipleinput-multiple-output (MIMO) antenna on a laptop is proposed for multiband LTE services. Each MIMO antenna consists of two planar inverted-F antenna (PIFA) elements, using a T-shaped dc line and two p-i-n diodes (D1 and D2), in conjunction with the proximity-coupled feed structure. By effectively minimizing its dimension and its interference with antenna performance, the proposed T-shaped dc line is designed to fit within the proximity-coupled feed structure. The proposed MIMO antenna covers the LTE 17/13 bands (704-787 MHz, VSWR 20 dB), low envelope correlation coefficient (ECC <; 0.0161), and total efficiency of greater than 51%, for all operating frequency bands.
74 citations
TL;DR: In this paper, a configuration of multiband and compact ultrawideband (UWB) antenna is presented, which is printed on a dielectric substrate and fed by microstrip line.
Abstract: A configuration of multiband and compact ultrawideband (UWB) antenna is present. The antenna is printed on a dielectric substrate and fed by microstrip line. The dimensions of square slots etched into the microstrip feedline can be used to tune the antennas' band-notch and bandwidth characteristics. This antenna is designed to cover the bandwidth for UWB applications (3.1-10.6 GHz) with a VSWR lower than 2 and provide sufficient rejection band notches for WiMAX (3.3-3.88 GHz), WLAN (4.96-6.23 GHz), and ITU (7.9-8.7 GHz). A better gain pattern is realized by inserting slots in the microstrip feedline, compared to the defected structure. Furthermore, by the analysis of the current distribution on the antenna surface, we can deduce the equivalent circuit of the antenna.
TL;DR: In this paper, a novel design for optically switching the resonant frequency of a microstrip patch antenna via photoconductive switches is proposed, and design considerations for maximizing frequency switching ratio with finite photo-conductance are investigated.
Abstract: In this letter, novel designs for optically switching the resonant frequency of a microstrip patch antenna via photoconductive switches are proposed, and design considerations for maximizing frequency switching ratio with finite photo-conductance are investigated. Furthermore, a configuration to switch the resonant frequency with low switch conductance is proposed for cheap and easy fabrication of a frequency-reconfigurable antenna that can be operated with low optical power. Experimental verification of the low-power configuration is presented.
TL;DR: In this paper, a compact multi-broadband planar antenna is proposed for wireless handsets, which covers multiple broad frequency bands, including the 900-MHz band with a bandwidth of 29% (790-1061 MHz), the 2-GHz band with bandwidth of 51% (1650-2775 MHz), and the 3.5/5 GHz band with an average bandwidth of 68% (3132-6382 MHz).
Abstract: A compact multi-broadband planar antenna is proposed for wireless handsets. The proposed antenna covers multiple broad frequency bands, including the 900-MHz band with a bandwidth of 29% (790-1061 MHz), the 2-GHz band with a bandwidth of 51% (1650-2775 MHz), and the 3.5/5-GHz band with a bandwidth of 68% (3132-6382 MHz). The multi-broadband antenna consists of a folded monopole coupling to an S-shaped strip for the 900-MHz band, a C-shaped monopole coupling with a C-shaped strip for the 2-GHz band, and a trapezoidal monopole with an inverted-F monopole for the 3.5/5-GHz band. All these monopoles with coupled strips are printed on a planar substrate with a compact size of 15 mm×60 mm×0.5 mm, suitable for emerging ultra-slim GSM/UMTS/LTE and WLAN/WiMAX handsets.
TL;DR: An antenna shape synthesis method is proposed that allows shaping of the antenna geometry prior to specification of the feed location and type to reduce the constraints placed on the optimization process and lead to potentially new designs due to the increased degree of freedom afforded.
Abstract: An antenna shape synthesis method is proposed that allows shaping of the antenna geometry prior to specification of the feed location and type. This reduces the constraints placed on the optimization process and can lead to potentially new designs due to the increased degree of freedom afforded. An appropriate feedpoint is easily chosen after shape optimization by selecting a location on the resulting structure for best impedance matching. The procedure is made possible through the use of characteristic mode concepts. Examples show that the antenna-Q values of the resulting shaped radiators closely approach the fundamental bounds.
TL;DR: A planar antenna array composed of two decoupled multiband wireless wide area network (WWAN) antenna elements for slim mobile phone application is presented and studied and its overall performances are measured and compared to simulated results to validate the proposed solution.
Abstract: A planar antenna array composed of two decoupled multiband wireless wide area network (WWAN) antenna elements for slim mobile phone application is presented and studied in this letter. A wide T-shaped protruded ground is deliberately designed to enhance the impedance matching and decouple the two closely deposed antenna elements. The integrity of the proposed T-shaped decoupling structure allows the reuse of space in between the antenna elements in the real applications. With small size occupation, the proposed antenna array covers two wide operating bands including 824-960 and 1710-2170 MHz, and within a short separating distance it achieves isolation better than 12 dB in the lower band and 15 dB in upper band. A prototype is fabricated, and the array's overall performances are measured and compared to simulated results to validate the proposed solution.
TL;DR: A general design of the coplanar waveguide excited IIFA, traditionally excited by a Microstrip or coaxial excitation, makes also the antenna more suitable to body area network (BAN) context by facilitating the integration on textile fabric or clothes, and the limitation of body effect at the operation frequency.
Abstract: A general design of the coplanar waveguide excited IIFA, traditionally excited by a Microstrip or coaxial excitation is presented. This coplanar excitation permits the bandwidth improvement (from around 10% to 50%) by the creation of a new resonance on the ground plane. It makes also the antenna more suitable to body area network (BAN) context by facilitating the integration on textile fabric or clothes, and the limitation of body effect at the operation frequency. The antenna principle is analyzed and general designs are presented. As application; a solution of a meandered IIFA integrated on Denim substrate is realized. All results are validated through comparative simulations and measurements.
29 May 2014
TL;DR: This paper refers to a detailed analysis on the design and implementation of 4×1 and 8×1 microstrip patch antenna (array) of given specifications using IE3D software and a dielectric material FR4 with dielectrics substrate permittivity of 4.28.
Abstract: This paper refers to a detailed analysis on the design and implementation of 4×1 and 8×1 microstrip patch antenna (array) of given specifications using IE3D software and a dielectric material FR4 with dielectric substrate permittivity of 4.28, tangent loss of 0.002 and height of 1.6 mm. The microstrip patch antenna array is designed for WLAN applications, at an operating frequency of 2.4 GHz with microstrip line feed and power dividers.
TL;DR: In this article, a single-cell tri-band composite right/left-handed (CRLH) resonant antenna is presented, which is designed on a single layer coplanar waveguide-fed based on the T-junction discontinuity equivalent circuit.
Abstract: A single-cell tri-band composite right/left-handed (CRLH) resonant antenna is presented. The antenna is designed on a single-layer coplanar waveguide-fed based on the T-junction discontinuity equivalent circuit. The proposed antenna provides compact size, easy fabrication process, multi-band feature and higher efficiency in comparison with the previously reported CRLH resonant antennas. The single-cell CRLH resonant antenna is fabricated and the measurements are consistent with the simulation result.
TL;DR: In this article, a two-port pattern diversity antenna is presented, which is a combination of a low-profile monocone antenna and a broadband microstrip antenna, which achieves an impedance bandwidth of 114% from 750MHz to 2.73 GHz, covering the GSM-850/900, GSM1800/1900/UMTS, and LTE800/2300/2500 bands.
Abstract: A two-port pattern diversity antenna is presented. The antenna is a combination of a low-profile monocone antenna and a broadband microstrip antenna. The low-profile monocone antenna is loaded with a cup-shaped patch and shorted with four metallic wires to the ground. The broadband microstrip antenna is fed by a probe-ring-slot coupling structure. The two antennas are integrated by sharing parts of the antenna radiators, resulting in a compact structure. The difficulties of placing coaxial cables are simply solved by reusing the shorting wires. A prototype of the proposed antenna is designed, fabricated, and measured. Its overall height is 3.915 cm. The low-profile monocone antenna achieves an impedance bandwidth of 114% from 750 MHz to 2.73 GHz, covering the GSM-850/900, GSM1800/1900/UMTS, and LTE800/2300/2500 bands. The broadband microstrip antenna provides an impedance bandwidth of 44% from 1.89 to 2.9 GHz, covering UMTS/LTE2300/2500 bands. The isolation between the two antennas is greater than 15 dB in the whole bands. The low-profile monocone antenna has a monopole-type radiation pattern, and the broadband microstrip antenna has a microstrip-antenna-type radiation pattern, which indicates that the proposed antenna can provide pattern diversity characteristics. The proposed antenna is suitable for 3G and 4G indoor applications and is also compatible with 2G (GSM) applications.
TL;DR: The proposed antenna is shown to have a robust performance with a user, and it can fulfill the specific absortion rate (SAR) and hearing aid compatibility (HAC) requirements, so it is well suited for future LTE-A mobile handsets.
Abstract: A novel design strategy for multi-standard mobile handset antennas is presented and verified with experimental results. The results show that the presented antenna operates with better than -3 dB (50%) efficiency across the frequencies of 698-2900 MHz and 3250-3600 MHz, thus having state-of-the-art performance. The antenna is shown to have a robust performance with a user, and it can fulfill the specific absortion rate (SAR) and hearing aid compatibility (HAC) requirements. In addition, it is demonstrated how the multi-antenna functionality can be included within the antenna structure, simultaneously achieving a small antenna volume of 750 mm3. The diversity gain and isolation are better than 10 dB at the frequency band 2110-3600 MHz. Hence, the proposed antenna is well suited for future LTE-A mobile handsets.
TL;DR: In this paper, a new dual-band and dual-polarized antenna is investigated in which two longitudinal and transverse slots on the broad wall of the substrate integrated waveguide (SIW) are responsible for creating two different frequency bands with distinct polarization.
Abstract: A new dual-band and dual-polarized antenna is investigated in this letter. Two longitudinal and transverse slots on the broad wall of the substrate integrated waveguide (SIW) are responsible for creating two different frequency bands with distinct polarization. A frequency selective surface (FSS) is placed on top of the microstrip patches to reduce the cross-polarization level of the antenna. The resonance frequencies of the patch and slot are set near to each other to get a wider impedance bandwidth. Bandwidth of more than 7% is achieved in each band. SIW feeding network increases the efficiency of the antenna. The simulated radiation efficiency of the antenna is better than 87% over the impedance bandwidth .
TL;DR: In this article, a simple antenna with simple feeding structure for broadband circular polarization is proposed, which is first designed with horizontal L-shaped strip (HLS) feeding, which feeds the radiation patch at orthogonal orientations with $90^\circ $ phase difference.
Abstract: A patch antenna with simple feeding structure for broadband circular polarization is proposed in this letter. The patch is first designed with horizontal L-shaped strip (HLS) feeding, which feeds the radiation patch at orthogonal orientations with $90^\circ $ phase difference. Two minimum points can be seen in the axial-ratio (AR) curve. By loading a shorting pin to the patch, the minimum point of lower frequency moves to higher frequency, and wide AR band is obtained consequently. Measured results show that 10-dB return-loss bandwidth of 23.6% (2.09–2.65 GHz), 3-dB AR bandwidth of 17.9% (2.18–2.61 GHz), and average gain of 8.5 dBic across the operating band are achieved for the proposed antenna with a low profile of $0.09\lambda_{0}$ ( ${\lambda _{0}}$ is the wavelength in free space corresponding to 2.4 GHz).
TL;DR: The proposed multiband antenna consists of a meandered planar inverted-F antenna with an additional branch line for wide bandwidth and a folded-loop antenna that provides a wide bandwidth to cover the hepta-band LTE/GSM/UMTS operation.
Abstract: This paper proposes a multiband antenna for LTE/GSM/UMTS band operation. The proposed antenna consists of a meandered planar inverted-F antenna with an additional branch line for wide bandwidth and a folded-loop antenna. The antenna provides a wide bandwidth to cover the hepta-band LTE/GSM/UMTS operation. The measured 6 dB return loss bandwidth is 169 MHz (793–962 MHz) at the low-frequency band and 1030 MHz (1700–2730 MHz) at the high-frequency band. The overall dimension of the proposed antenna is 55 mm × 110 mm × 5 mm.
Patent•
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07 May 2014
TL;DR: In planar inverted-F antenna configurations, a folded ground may be formed on the top of the PCB for reducing system area while maintaining suitable performance in terms of radiation pattern, radiation efficiency and impedance bandwidth.
Abstract: Various planar inverted-F antenna configurations may include an antenna element formed on the top of a PCB and a ground element formed on the bottom of the PCB. Two or more slots may be included in the antenna element for reducing the antenna area while maintaining a suitable impedance bandwidth. A slot may be included in the ground element for reducing the ground area while increasing radiation efficiency. A folded ground may be formed on the top of the PCB for reducing system area while maintaining suitable performance. By moving the folded ground closer to the antenna element and increasing the PCB thickness, significant reductions in system area may be achieved, while maintaining or improving performance in terms of radiation pattern, radiation efficiency and impedance bandwidth.
TL;DR: In this article, a dual-band circularly polarized stacked microstrip patch antenna with a small frequency ratio is presented, where the lower patch is having a pair of peripheral cuts in the circular patch with cross slot loaded at the center.
Abstract: A single feed dual-band circularly polarized stacked microstrip patch antenna with a small frequency ratio is presented. The lower patch is having a pair of peripheral cuts in the circular patch with cross slot loaded at the center and truncated corner square ring is used as the parasitic patch. The frequency ratio of dual-band achieved is 1.05. The 3-dB axial ratio bandwidth is 1.4% for the upper band and 1.1% for the lower band. Proposed structure is fabricated on the FR-4 epoxy substrate and fed by SMA connector. The measured results are in good agreement with the simulated. The antenna shows stable radiation characteristics for both the operating bands. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1933–1937, 2014
TL;DR: In this article, a planar structure was designed for an early heart failure detection system operating at the ultra-high frequency (UHF) band, which achieved a peak gain of 4.2 dBi, front-to-back ratio of 7-13 dB and efficiency of more than 87% over 62% fractional bandwidth (560-1060 MHz) at 10dB return-loss reference.
Abstract: A wideband folded antenna, which is specifically designed for an early heart failure detection system operating at the ultra-high frequency (UHF) band, is presented. The design procedure starts with a planar structure that includes a loop antenna, a dual monopole, and a loaded parasitic patch. To significantly reduce the size of the antenna and achieve directional radiation as needed for the intended application, the planar structure is folded to form a three-dimensional antenna with the dimensions $0.1\lambda\times 0.29\lambda\times 0.09\lambda$ , where $\lambda$ is the wavelength at the lowest operating frequency. The final tested antenna achieves a peak gain of 4.2 dBi, front-to-back ratio of 7–13 dB and efficiency of more than 87% over 62% fractional bandwidth (560–1060 MHz) at 10-dB return-loss reference. The antenna in addition to a compact microwave transceiver and an adjustable platform are then used to build a monostatic-radar-based heart failure detection system. The system is tested on an artificial torso phantom to verify the potential of such a system in the early detection of heart failure. The used imaging algorithm and obtained promising results are reported in the letter.
TL;DR: In this paper, a compact, semi-circular, implantable, planar-inverted-F antenna (PIFA) is presented for the medical implant communications services (MICSs) band (402-405 MHz).
Abstract: A novel, compact, semi-circular, implantable, planar-inverted-F antenna (PIFA) is presented for the medical implant communications services (MICSs) band (402–405 MHz). By cutting three arc-shaped slots in a semi-circular patch, the proposed antenna can obtain effective size reduction. The total volume of the proposed antenna, including substrate and superstrate, is about 151 mm3. A bandwidth of 25 MHz is obtained at return loss of 10 dB. In addition, the radiation and specific absorption rate (SAR) performance of the antenna are examined and characterised.
Patent•
21 Jul 2014
TL;DR: In this article, a system and method for diversity implementation are provided, where diversity gains are obtained by using a hybrid of the switching technique and the combining technique in conjunction with the use of a modal antenna.
Abstract: A system and method for diversity implementation are provided, where diversity gains are obtained by using a hybrid of the switching technique and the combining technique in conjunction with the use of a modal antenna. The antenna system includes multiple antennas including at least one modal antenna that has multiple modes, and a processor for selecting one or more modes from the multiple modes associated with each of the at least one modal antenna, combining modes to form one or more combinations of modes, the modes in each of the one or more combinations including one of the one or more selected modes associated with each of the at least one modal antenna, and selecting one of the one or more combinations that optimizes correlation and/or a quality metric for diversity.
TL;DR: In this article, a compact MIMO antenna for LTE-13 band (746-787 MHz) applications is proposed, which consists of two symmetrical planar inverted-F antennas (PIFAs) in conjunction with a T-shaped common radiator.
Abstract: A compact (60 × 15 × 5 mm 3) mobile handset multiple-input-multiple-output (MIMO) antenna for LTE 13 band (746-787 MHz) applications is proposed. The antenna consists of two symmetrical planar inverted-F antennas (PIFAs) in conjunction with a T-shaped common radiator. Without using any additional coupling elements between these closely mounted antennas, both high isolation ( > 17 dB) and low envelope correlation coefficient (ECC <; 0.05 ) are achieved. The low ECC is achieved by using diagonally orthogonal radiation patterns from optimized locations of the MIMO antenna feeds and elements. Low mutual coupling achieved by using the T-shaped common radiator gives rise to the high isolation.
TL;DR: In this article, a planar folded dipole antenna is proposed for wideband dual-element planar antenna with a 10-dB return-loss operating bandwidth of 107% (1.23 ~ 4.07 GHz) with better than 10 dB return loss.
Abstract: A wideband dual-element planar folded dipole antenna is proposed in this letter. It is composed of a pair of asymmetric coplanar strip folded dipoles. The dual-element folded dipole antenna is fed by a microstrip feedline. With suitable design of the asymmetric coplanar strip folded dipole and the microstrip feedline, a 10-dB return-loss operating bandwidth of 107% (1.23 ~ 4.07 GHz) is achieved. By adding a metal plate, a wideband unidirectional antenna can be obtained with a measured impedance bandwidth of 113% (1.15 ~ 4.07 GHz) with better than 10 dB return loss. Its fabricated prototype is also measured with stable unidirectional radiation patterns in working band 1.13 ~ 3.3 GHz with a gain in + z-direction higher than 8.2 dBi and a front-to-back ratio better than 11.5 dB.