The Experts below are selected from a list of 103494 Experts worldwide ranked by ideXlab platform
Mohammad Said Sharawi - One of the best experts on this subject based on the ideXlab platform.
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4-Element Concentric Pentagonal Slot-Line-Based Ultra-Wide Tuning Frequency Reconfigurable MIMO Antenna System
IEEE Transactions on Antennas and Propagation, 2018Co-Authors: Rifaqat Hussain, Mohammad Said Sharawi, Atif ShamimAbstract:In this communication, a novel, compact, ultrawideband tuning, concentric pentagonal slot-line-based frequency-reconfigurable multiple-input-multiple-output (MIMO) Antenna System is presented. It consists of a four-element Antenna design on a commercially available FR-4 substrate with the dimensions of $60\times 120\times 1.56$ mm3. All the Antenna elements are planar in structure, which are etched out from ground plane. Frequency reconfigurability is achieved using varactor diodes by reactively loading the Antennas. Each capacitance value of the varactor diode results in the triband operation. Proper capacitive reactance loading enables the Antenna to resonate over a wide frequency band. The proposed MIMO Antenna System is tuned over an ultrawide frequency band, and a smooth variation of the resonance frequencies is observed from 1.32 to 1.49 and 1.75 to 5.2 GHz. Moreover, the unique feature of the proposed Antenna System is the effectiveness of reactively loading the slot over all the resonating bands. The proposed Antenna System is compact and suitable to be used in wireless handheld devices and mobile terminals for cognitive radio applications. The envelope correlation coefficient did not exceed 0.186 in the entire operating band of the MIMO Antenna operation. The maximum measured gain of the MIMO Antenna is 4.5 dBi with a maximum efficiency of 81%.
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An Integrated Four-Element Slot-Based MIMO and a UWB Sensing Antenna System for CR Platforms
IEEE Transactions on Antennas and Propagation, 2018Co-Authors: Rifaqat Hussain, Mohammad Said Sharawi, Atif ShamimAbstract:This communication presents a novel integrated Antenna System for cognitive radio (CR) applications. The design consists of a compact four-element reconfigurable annular slot-based multiple-input-multiple-output (MIMO) Antenna System integrated within an ultrawideband (UWB) sensing Antenna. All the Antenna elements are planar in structure and designed on a single substrate ( RO-4350 ) with dimensions $60\times 120\times 1.5$ mm3. The frequency reconfigurable slot-based MIMO Antenna System is tuned over a wide frequency band from 1.77 to 2.51 GHz while the UWB sensing Antenna is covering from 0.75 to 7.65 GHz The proposed Antenna System is suitable for CR enabled wireless devices. The envelop correlation coefficient did not exceed 0.248 in the entire operating band of the MIMO Antenna part. The maximum measured gain of the MIMO Antenna is 3.2 dBi with a maximum efficiency of 81%.
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4G/5G Antenna System with dual function planar connected array
Iet Microwaves Antennas & Propagation, 2017Co-Authors: Muhammad Ikram, Rifaqat Hussain, Mohammad Said SharawiAbstract:An integrated design consisting of a multiple-input-multiple-output (MIMO) Antenna System for fourth generation applications and a planar connected array (PCA) for fifth generation applications is presented. The proposed design contains a 4-element printed-inverted-F Antenna-based MIMO Antenna System and a slot-based PCA. The Antenna System is fabricated on a commercially available RO-4350 substrate with er equal to 3.5. The dimensions of the board are 100 × 60 × 0.76 mm 3 representing a typical smart phone backplane size. The Antenna System covers 2.1 and 12.5 GHz frequency bands via its MIMO and PCA parts, respectively. The design is planar, low profile and compact in structure that is suitable for wireless handheld devices and mobile terminals. The PCA also serves as a defected ground structure at 2.1 GHz thus having two functions. Isolation is improved by at least 4 dB. The PCA consists of a 4 × 3 radiating slots fed via a corporate feed structure. The measured gain and efficiency values at the centre frequency are at least 3.4 dBi and 74%, respectively, for the MIMO Antenna System and 8 dBi and 80% for the PCA. The envelope correlation coefficient did not exceed 0.2824 for all Antennas showing good MIMO performance.
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a two concentric slot loop based connected array mimo Antenna System for 4g 5g terminals
IEEE Transactions on Antennas and Propagation, 2017Co-Authors: Mohammad Said Sharawi, Muhammad Ikram, Atif ShamimAbstract:In this paper, an integrated design with a multiple-input multiple-output (MIMO) Antenna System for fourth generation (4G) and fifth generation (5G) applications is presented. The proposed design contains a two-element slot-based MIMO Antenna System for 4G and a connected Antenna array (CAA)-based two-element MIMO Antenna System for a potential 5G band. Two rectangular loops are etched on the periphery of the ground plane. The top and bottom portions of the thin loops act as the two 4G MIMO Antennas, while parts of their sides are acting as 5G arrays. The Antenna System is fabricated on a commercially available Roger 4350 substrate with $\epsilon _{r}$ equal to 3.5, while the dimensions of the board are $100\times 60 \times 0.76$ mm3 representing a typical smart phone back plane size. The integrated Antenna System covers multibands at 4G with a combined bandwidth of 1.565 GHz (−6 dB BW) in addition to the band between 16.50 and 17.80 GHz for 5G. The design is planar, low profile, simple, and compact in structure making suitable for wireless handheld devices and mobile terminals. The measured gain at 3.46 GHz was at least 2.22 dBi and at 17 GHz was 8 dBi for the 4G and 5G MIMO Antenna Systems, respectively. The envelope correlation coefficient was also calculated from the measured 3-D patterns and showed good MIMO performance. This is the first integrated 4G/5G MIMO Antenna System with below 6 GHz and above 10-GHz covered bands using CAA.
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Dielectric resonator based MIMO Antenna System enabling millimetre-wave mobile devices
IET Microwaves, Antennas & Propagation, 2017Co-Authors: Mohammad Said Sharawi, Mohamed T. Hussain, Symon K. Podilchak, Yahia M. M. AntarAbstract:In this study, a millimetre-wave dielectric resonator (DR)-based multiple-input-multiple-output (MIMO) Antenna System based on two linear arrays is presented. Each array that represents a single MIMO Antenna consists of four cylindrical DR Antenna (cDRA) elements operating at 30 GHz with a bandwidth of at least 1 GHz. Each array is designed with a fixed beam direction which is tilted to provide low field correlation. A passive microstrip-based feed network was designed to achieve this beam tilting enabling suitable magnitude and phase excitation of the individual cDRAs for radiation. The complete Antenna System was designed on a two-layer substrate occupying 48 mm × 21 mm. Excellent field correlation values were measured (below 0.002) across the band of operation while peak gains were >7 dBi. High radiation efficiency is obtained. The proposed design approach for beam tilting, which enables MIMO operation, may also be useful for other compact implementations to support 5G communications.
Atif Shamim - One of the best experts on this subject based on the ideXlab platform.
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massive mimo Antenna System for 5g base stations with directive ports and switched beamsteering capabilities
Iet Microwaves Antennas & Propagation, 2018Co-Authors: Monjed A Altarifi, Mohammad S Sharawi, Atif ShamimAbstract:A 72-port (288 Antennas) triangular-shaped massive multiple-input-multiple-output (mMIMO) Antenna System is presented for fifth generation (5G) base stations. Each side of the Antenna System consists of three layers with a total size of 44.4 × 29.6 × 0.1524 cm 3 , and contains 24 ports. Each port (subarray) consists of 2 × 2 patches on the top layer, their feeding network with pre-calculated phases is on the bottom layer and the ground plane is in the middle one. Each port is fed in a way to tilt its beam direction with respect to others to achieve uncorrelated individual patterns. The Antenna System is the first to support two operating modes: simultaneous individual port operation (i.e. 72-port MIMO) and mMIMO array operation (i.e. with beam switching). The measured bandwidth is 100 MHz that covers the band from 3.45 to 3.55 GHz. The measured gain of a single port equals to 9.41 dBi. The envelop correlation coefficient does not exceed 0.1198. A beamsteering method to steer the beam of each 24-port side to different locations in the space is presented and applied based on the non-uniform port patterns (unlike most conventional methods). Thirteen switched beams are obtained with centre angle coverage up to 34° in elevation with maximum gain of 19.5 dBi.
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4-Element Concentric Pentagonal Slot-Line-Based Ultra-Wide Tuning Frequency Reconfigurable MIMO Antenna System
IEEE Transactions on Antennas and Propagation, 2018Co-Authors: Rifaqat Hussain, Mohammad Said Sharawi, Atif ShamimAbstract:In this communication, a novel, compact, ultrawideband tuning, concentric pentagonal slot-line-based frequency-reconfigurable multiple-input-multiple-output (MIMO) Antenna System is presented. It consists of a four-element Antenna design on a commercially available FR-4 substrate with the dimensions of $60\times 120\times 1.56$ mm3. All the Antenna elements are planar in structure, which are etched out from ground plane. Frequency reconfigurability is achieved using varactor diodes by reactively loading the Antennas. Each capacitance value of the varactor diode results in the triband operation. Proper capacitive reactance loading enables the Antenna to resonate over a wide frequency band. The proposed MIMO Antenna System is tuned over an ultrawide frequency band, and a smooth variation of the resonance frequencies is observed from 1.32 to 1.49 and 1.75 to 5.2 GHz. Moreover, the unique feature of the proposed Antenna System is the effectiveness of reactively loading the slot over all the resonating bands. The proposed Antenna System is compact and suitable to be used in wireless handheld devices and mobile terminals for cognitive radio applications. The envelope correlation coefficient did not exceed 0.186 in the entire operating band of the MIMO Antenna operation. The maximum measured gain of the MIMO Antenna is 4.5 dBi with a maximum efficiency of 81%.
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highly miniaturised semi loop meandered dual band mimo Antenna System
Iet Microwaves Antennas & Propagation, 2018Co-Authors: Syed S. Jehangir, Mohammad S Sharawi, Atif ShamimAbstract:A novel dual-band two-element directional multiple-input-multiple-output (MIMO) Antenna System is presented with 68% miniaturisation, which is achieved using a semi-loop meandered driven element and a small ground plane. The centre frequency of operation is 2 GHz. The Antenna System covers two bands: the telemetry L-band 1.27-1.43 GHz and the global System for mobile communications/long-term evolution band 1.8-2.133 GHz. The simulation and measurement results are in good agreement. The proposed Antenna System mimics the quasi-Yagi Antenna configuration with a measured front-to-back ratio of around 15 dB at 1.35 GHz and 17 dB at 2 GHz, which is achieved without using a large ground plane, extra metallic structures, multiple reflector elements, or any complex technique. A gain of more than 5 dBi is measured for the single element with a total radiation efficiency of around 85% in both bands. The measured isolation of the proposed MIMO Antenna is more than 15 dB with <;0.0785 measured envelope correlation coefficient values in both bands.
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An Integrated Four-Element Slot-Based MIMO and a UWB Sensing Antenna System for CR Platforms
IEEE Transactions on Antennas and Propagation, 2018Co-Authors: Rifaqat Hussain, Mohammad Said Sharawi, Atif ShamimAbstract:This communication presents a novel integrated Antenna System for cognitive radio (CR) applications. The design consists of a compact four-element reconfigurable annular slot-based multiple-input-multiple-output (MIMO) Antenna System integrated within an ultrawideband (UWB) sensing Antenna. All the Antenna elements are planar in structure and designed on a single substrate ( RO-4350 ) with dimensions $60\times 120\times 1.5$ mm3. The frequency reconfigurable slot-based MIMO Antenna System is tuned over a wide frequency band from 1.77 to 2.51 GHz while the UWB sensing Antenna is covering from 0.75 to 7.65 GHz The proposed Antenna System is suitable for CR enabled wireless devices. The envelop correlation coefficient did not exceed 0.248 in the entire operating band of the MIMO Antenna part. The maximum measured gain of the MIMO Antenna is 3.2 dBi with a maximum efficiency of 81%.
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a two concentric slot loop based connected array mimo Antenna System for 4g 5g terminals
IEEE Transactions on Antennas and Propagation, 2017Co-Authors: Mohammad Said Sharawi, Muhammad Ikram, Atif ShamimAbstract:In this paper, an integrated design with a multiple-input multiple-output (MIMO) Antenna System for fourth generation (4G) and fifth generation (5G) applications is presented. The proposed design contains a two-element slot-based MIMO Antenna System for 4G and a connected Antenna array (CAA)-based two-element MIMO Antenna System for a potential 5G band. Two rectangular loops are etched on the periphery of the ground plane. The top and bottom portions of the thin loops act as the two 4G MIMO Antennas, while parts of their sides are acting as 5G arrays. The Antenna System is fabricated on a commercially available Roger 4350 substrate with $\epsilon _{r}$ equal to 3.5, while the dimensions of the board are $100\times 60 \times 0.76$ mm3 representing a typical smart phone back plane size. The integrated Antenna System covers multibands at 4G with a combined bandwidth of 1.565 GHz (−6 dB BW) in addition to the band between 16.50 and 17.80 GHz for 5G. The design is planar, low profile, simple, and compact in structure making suitable for wireless handheld devices and mobile terminals. The measured gain at 3.46 GHz was at least 2.22 dBi and at 17 GHz was 8 dBi for the 4G and 5G MIMO Antenna Systems, respectively. The envelope correlation coefficient was also calculated from the measured 3-D patterns and showed good MIMO performance. This is the first integrated 4G/5G MIMO Antenna System with below 6 GHz and above 10-GHz covered bands using CAA.
Rifaqat Hussain - One of the best experts on this subject based on the ideXlab platform.
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stacked frequency reconfigurable yagi like mimo Antenna System
Iet Microwaves Antennas & Propagation, 2020Co-Authors: Rifaqat Hussain, Syed S. Jehangir, Muhammad Usman Khan, Mohammad S SharawiAbstract:In this work, a 2-layer frequency reconfigurable Yagi-like multiple-input–multiple-output (MIMO) Antenna System is proposed based on a closed pentagonal slot-loop excitation. The MIMO System consists of 4 identical active Antenna elements reactively loaded with varactor diodes to achieve frequency reconfigurability over a band from 1.5 to 2.1 GHz. The distinguishing feature of the proposed work is achieving Yagi-like directional characteristics over a very wide frequency band. The conventional omni-directional pattern of a slot Antenna is made directional by using a parasitic metallic reflector layer below the substrate. By using the reflector element, the back-lobe radiation is highly suppressed and a front-to-back ratio of 5–13 dB is achieved within the entire frequency band of operation. The proposed design is compact with an overall size of 100 × 100 × 20 mm 3 , and a reflector size of 110 × 110 mm 2 . A single element has a maximum peak gain of 4 dBi and total measured radiation efficiency of 76%. The Antenna System also shows good MIMO performance with high port isolation of 11.3 dB and very low envelope correlation coefficient values within the operational band.
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4-Element Concentric Pentagonal Slot-Line-Based Ultra-Wide Tuning Frequency Reconfigurable MIMO Antenna System
IEEE Transactions on Antennas and Propagation, 2018Co-Authors: Rifaqat Hussain, Mohammad Said Sharawi, Atif ShamimAbstract:In this communication, a novel, compact, ultrawideband tuning, concentric pentagonal slot-line-based frequency-reconfigurable multiple-input-multiple-output (MIMO) Antenna System is presented. It consists of a four-element Antenna design on a commercially available FR-4 substrate with the dimensions of $60\times 120\times 1.56$ mm3. All the Antenna elements are planar in structure, which are etched out from ground plane. Frequency reconfigurability is achieved using varactor diodes by reactively loading the Antennas. Each capacitance value of the varactor diode results in the triband operation. Proper capacitive reactance loading enables the Antenna to resonate over a wide frequency band. The proposed MIMO Antenna System is tuned over an ultrawide frequency band, and a smooth variation of the resonance frequencies is observed from 1.32 to 1.49 and 1.75 to 5.2 GHz. Moreover, the unique feature of the proposed Antenna System is the effectiveness of reactively loading the slot over all the resonating bands. The proposed Antenna System is compact and suitable to be used in wireless handheld devices and mobile terminals for cognitive radio applications. The envelope correlation coefficient did not exceed 0.186 in the entire operating band of the MIMO Antenna operation. The maximum measured gain of the MIMO Antenna is 4.5 dBi with a maximum efficiency of 81%.
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An Integrated Four-Element Slot-Based MIMO and a UWB Sensing Antenna System for CR Platforms
IEEE Transactions on Antennas and Propagation, 2018Co-Authors: Rifaqat Hussain, Mohammad Said Sharawi, Atif ShamimAbstract:This communication presents a novel integrated Antenna System for cognitive radio (CR) applications. The design consists of a compact four-element reconfigurable annular slot-based multiple-input-multiple-output (MIMO) Antenna System integrated within an ultrawideband (UWB) sensing Antenna. All the Antenna elements are planar in structure and designed on a single substrate ( RO-4350 ) with dimensions $60\times 120\times 1.5$ mm3. The frequency reconfigurable slot-based MIMO Antenna System is tuned over a wide frequency band from 1.77 to 2.51 GHz while the UWB sensing Antenna is covering from 0.75 to 7.65 GHz The proposed Antenna System is suitable for CR enabled wireless devices. The envelop correlation coefficient did not exceed 0.248 in the entire operating band of the MIMO Antenna part. The maximum measured gain of the MIMO Antenna is 3.2 dBi with a maximum efficiency of 81%.
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4G/5G Antenna System with dual function planar connected array
Iet Microwaves Antennas & Propagation, 2017Co-Authors: Muhammad Ikram, Rifaqat Hussain, Mohammad Said SharawiAbstract:An integrated design consisting of a multiple-input-multiple-output (MIMO) Antenna System for fourth generation applications and a planar connected array (PCA) for fifth generation applications is presented. The proposed design contains a 4-element printed-inverted-F Antenna-based MIMO Antenna System and a slot-based PCA. The Antenna System is fabricated on a commercially available RO-4350 substrate with er equal to 3.5. The dimensions of the board are 100 × 60 × 0.76 mm 3 representing a typical smart phone backplane size. The Antenna System covers 2.1 and 12.5 GHz frequency bands via its MIMO and PCA parts, respectively. The design is planar, low profile and compact in structure that is suitable for wireless handheld devices and mobile terminals. The PCA also serves as a defected ground structure at 2.1 GHz thus having two functions. Isolation is improved by at least 4 dB. The PCA consists of a 4 × 3 radiating slots fed via a corporate feed structure. The measured gain and efficiency values at the centre frequency are at least 3.4 dBi and 74%, respectively, for the MIMO Antenna System and 8 dBi and 80% for the PCA. The envelope correlation coefficient did not exceed 0.2824 for all Antennas showing good MIMO performance.
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Annular Slot-Based Miniaturized Frequency-Agile MIMO Antenna System
IEEE Antennas and Wireless Propagation Letters, 2017Co-Authors: Rifaqat Hussain, Asim Ghalib, Mohammad Said SharawiAbstract:In this letter, a miniaturized annular slot-based multiple-input–multiple-output (MIMO) Antenna System is presented. The proposed frequency-agile Antenna exhibits wide tuning range operation by covering several well known wireless standards including GSM1800/LTE/UMTS/WLAN along with several others. The resonance frequency varies from 1.8 to 2.45 GHz. The structure of each Antenna element consists of a combination of annular and circular slots, and the Antenna is made reconfigurable using a varactor diode within its annular slot. Only one varactor diode is used in achieving this wide tuning band of operation. The four-element MIMO Antenna System is realized on a $\text{60} \times \text{120}\times \text{0.76}$ -mm $^3$ RO4350 substrate. The proposed design is suitable for wireless handheld devices and mobile terminals as well as cognitive radio front ends. The measured results show maximum gain of 2.43 dBi and maximum efficiency ( $\eta$ ) of 73%. The envelope correlation coefficient did not exceed 0.186 across the complete operating bands.
Mohammad S Sharawi - One of the best experts on this subject based on the ideXlab platform.
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stacked frequency reconfigurable yagi like mimo Antenna System
Iet Microwaves Antennas & Propagation, 2020Co-Authors: Rifaqat Hussain, Syed S. Jehangir, Muhammad Usman Khan, Mohammad S SharawiAbstract:In this work, a 2-layer frequency reconfigurable Yagi-like multiple-input–multiple-output (MIMO) Antenna System is proposed based on a closed pentagonal slot-loop excitation. The MIMO System consists of 4 identical active Antenna elements reactively loaded with varactor diodes to achieve frequency reconfigurability over a band from 1.5 to 2.1 GHz. The distinguishing feature of the proposed work is achieving Yagi-like directional characteristics over a very wide frequency band. The conventional omni-directional pattern of a slot Antenna is made directional by using a parasitic metallic reflector layer below the substrate. By using the reflector element, the back-lobe radiation is highly suppressed and a front-to-back ratio of 5–13 dB is achieved within the entire frequency band of operation. The proposed design is compact with an overall size of 100 × 100 × 20 mm 3 , and a reflector size of 110 × 110 mm 2 . A single element has a maximum peak gain of 4 dBi and total measured radiation efficiency of 76%. The Antenna System also shows good MIMO performance with high port isolation of 11.3 dB and very low envelope correlation coefficient values within the operational band.
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a compact single layer four port orthogonally polarized yagi like mimo Antenna System
IEEE Transactions on Antennas and Propagation, 2020Co-Authors: Syed S. Jehangir, Mohammad S SharawiAbstract:A wideband compact Yagi-like directional multiple-input–multiple-output (MIMO) Antenna System is presented based on a slot loop excitation. Four orthogonally polarized beams are generated by orthogonally feeding the slot loop elements using microstrip lines. The proposed design is based on a single-layer geometry with an overall size of $35\times 90\times 0.76$ mm3, which is suitable for compact wireless handheld devices. The conventional vertically polarized omnidirectional beams from each slot loop element are made directional and horizontally polarized by using two passive complementary slot reflector (CSR) elements. The Antenna System has a wide measured bandwidth of 620 MHz (3.26–3.88 GHz) targeting the 3.6 GHz WiMAX band. It has a maximum realized gain of 4 dBi and front to back ratio (FBR) of more than 7 dB within the band of operation. The proposed Antenna System shows good MIMO performance with a minimum measured isolation of 10 dB between the adjacent ports and more than 20 dB between other ports. The orthogonal beams of the Antenna System help in achieving low envelope correlation coefficient (ECC) values of less than 0.1. The measured total efficiency of the Antenna System is more than 75% for all the ports of the Antenna System.
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massive mimo Antenna System for 5g base stations with directive ports and switched beamsteering capabilities
Iet Microwaves Antennas & Propagation, 2018Co-Authors: Monjed A Altarifi, Mohammad S Sharawi, Atif ShamimAbstract:A 72-port (288 Antennas) triangular-shaped massive multiple-input-multiple-output (mMIMO) Antenna System is presented for fifth generation (5G) base stations. Each side of the Antenna System consists of three layers with a total size of 44.4 × 29.6 × 0.1524 cm 3 , and contains 24 ports. Each port (subarray) consists of 2 × 2 patches on the top layer, their feeding network with pre-calculated phases is on the bottom layer and the ground plane is in the middle one. Each port is fed in a way to tilt its beam direction with respect to others to achieve uncorrelated individual patterns. The Antenna System is the first to support two operating modes: simultaneous individual port operation (i.e. 72-port MIMO) and mMIMO array operation (i.e. with beam switching). The measured bandwidth is 100 MHz that covers the band from 3.45 to 3.55 GHz. The measured gain of a single port equals to 9.41 dBi. The envelop correlation coefficient does not exceed 0.1198. A beamsteering method to steer the beam of each 24-port side to different locations in the space is presented and applied based on the non-uniform port patterns (unlike most conventional methods). Thirteen switched beams are obtained with centre angle coverage up to 34° in elevation with maximum gain of 19.5 dBi.
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highly miniaturised semi loop meandered dual band mimo Antenna System
Iet Microwaves Antennas & Propagation, 2018Co-Authors: Syed S. Jehangir, Mohammad S Sharawi, Atif ShamimAbstract:A novel dual-band two-element directional multiple-input-multiple-output (MIMO) Antenna System is presented with 68% miniaturisation, which is achieved using a semi-loop meandered driven element and a small ground plane. The centre frequency of operation is 2 GHz. The Antenna System covers two bands: the telemetry L-band 1.27-1.43 GHz and the global System for mobile communications/long-term evolution band 1.8-2.133 GHz. The simulation and measurement results are in good agreement. The proposed Antenna System mimics the quasi-Yagi Antenna configuration with a measured front-to-back ratio of around 15 dB at 1.35 GHz and 17 dB at 2 GHz, which is achieved without using a large ground plane, extra metallic structures, multiple reflector elements, or any complex technique. A gain of more than 5 dBi is measured for the single element with a total radiation efficiency of around 85% in both bands. The measured isolation of the proposed MIMO Antenna is more than 15 dB with <;0.0785 measured envelope correlation coefficient values in both bands.
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a cognitive radio reconfigurable mimo and sensing Antenna System
IEEE Antennas and Wireless Propagation Letters, 2015Co-Authors: Rifaqat Hussain, Mohammad S SharawiAbstract:A planar, compact, single-substrate, multiband, frequency-reconfigurable multiple-input–multiple-output (MIMO) Antenna System is presented. The proposed Antenna elements are integrated with an ultrawideband (UWB) sensing Antenna to develop a complete Antenna platform for cognitive radio (CR) applications. The dual-element MIMO Antenna is integrated with p-i-n and varactor diodes for frequency reconfigurability. Two modes of selection are used for the MIMO Antenna System reconfigurability along with varactor tuning to sweep the frequency over a wide band especially below 1 GHz. The proposed sensing Antenna is used to cover a wide range of frequency bands from $720\sim3440~\hbox{MHz}$ . The complete System comprising the multiband reconfigurable MIMO Antennas and UWB sensing Antenna for CR applications is proposed with a compact form factor. The Antenna System is developed on a single substrate area of dimensions $65\times120\times1.56~\hbox{mm}^3$ .
Muhammad Ikram - One of the best experts on this subject based on the ideXlab platform.
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multiband mimo microwave and millimeter Antenna System employing dual function tapered slot structure
IEEE Transactions on Antennas and Propagation, 2019Co-Authors: Muhammad Ikram, Nghia Nguyentrong, A M AbboshAbstract:A single-layered multiple-input multiple-output (MIMO) Antenna System is presented for future wireless devices operating at WLAN (2.45 GHz, 5.2 GHz), 4G LTE (2.6 GHz) and 5G (24 GHz, 28 GHz) bands. The design consists of a dual-band four-element monopole MIMO Antenna System that covers the 2.45 GHz and 5.2 GHz bands. A decoupling mechanism is designed in the ground plane based on a tapered slot. This tapered slot has a dual function, working both as a decoupling structure ( $\lambda _{0}/4$ long) at 2.45 GHz and as a tapered slot Antenna ( $3\lambda _{0}$ long) at 28 GHz when excited by a proper feeder. The proposed MIMO Antenna System is designed on an RO-5880 substrate with overall dimensions of $104$ mm $\times 104$ mm $\times 0.51$ mm. The measured results show that the presented design covers two low-frequency bands (from 2.40 GHz to 5.1 GHz, from 5.1 GHz to 5.6 GHz) with a peak gain of 5 dBi and one high-frequency band (from 23 GHz to 30 GHz) with a peak gain of 11 dBi. The minimum measured isolation between the two Antennas is more than 16 dB, while the maximum envelope correlation coefficient value is less than 0.16 showing good MIMO characteristics.
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4G/5G Antenna System with dual function planar connected array
Iet Microwaves Antennas & Propagation, 2017Co-Authors: Muhammad Ikram, Rifaqat Hussain, Mohammad Said SharawiAbstract:An integrated design consisting of a multiple-input-multiple-output (MIMO) Antenna System for fourth generation applications and a planar connected array (PCA) for fifth generation applications is presented. The proposed design contains a 4-element printed-inverted-F Antenna-based MIMO Antenna System and a slot-based PCA. The Antenna System is fabricated on a commercially available RO-4350 substrate with er equal to 3.5. The dimensions of the board are 100 × 60 × 0.76 mm 3 representing a typical smart phone backplane size. The Antenna System covers 2.1 and 12.5 GHz frequency bands via its MIMO and PCA parts, respectively. The design is planar, low profile and compact in structure that is suitable for wireless handheld devices and mobile terminals. The PCA also serves as a defected ground structure at 2.1 GHz thus having two functions. Isolation is improved by at least 4 dB. The PCA consists of a 4 × 3 radiating slots fed via a corporate feed structure. The measured gain and efficiency values at the centre frequency are at least 3.4 dBi and 74%, respectively, for the MIMO Antenna System and 8 dBi and 80% for the PCA. The envelope correlation coefficient did not exceed 0.2824 for all Antennas showing good MIMO performance.
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a two concentric slot loop based connected array mimo Antenna System for 4g 5g terminals
IEEE Transactions on Antennas and Propagation, 2017Co-Authors: Mohammad Said Sharawi, Muhammad Ikram, Atif ShamimAbstract:In this paper, an integrated design with a multiple-input multiple-output (MIMO) Antenna System for fourth generation (4G) and fifth generation (5G) applications is presented. The proposed design contains a two-element slot-based MIMO Antenna System for 4G and a connected Antenna array (CAA)-based two-element MIMO Antenna System for a potential 5G band. Two rectangular loops are etched on the periphery of the ground plane. The top and bottom portions of the thin loops act as the two 4G MIMO Antennas, while parts of their sides are acting as 5G arrays. The Antenna System is fabricated on a commercially available Roger 4350 substrate with $\epsilon _{r}$ equal to 3.5, while the dimensions of the board are $100\times 60 \times 0.76$ mm3 representing a typical smart phone back plane size. The integrated Antenna System covers multibands at 4G with a combined bandwidth of 1.565 GHz (−6 dB BW) in addition to the band between 16.50 and 17.80 GHz for 5G. The design is planar, low profile, simple, and compact in structure making suitable for wireless handheld devices and mobile terminals. The measured gain at 3.46 GHz was at least 2.22 dBi and at 17 GHz was 8 dBi for the 4G and 5G MIMO Antenna Systems, respectively. The envelope correlation coefficient was also calculated from the measured 3-D patterns and showed good MIMO performance. This is the first integrated 4G/5G MIMO Antenna System with below 6 GHz and above 10-GHz covered bands using CAA.