The Experts below are selected from a list of 28650 Experts worldwide ranked by ideXlab platform

Yury A. Andreev - One of the best experts on this subject based on the ideXlab platform.

  • optimizing high power ultra wideband combined Antennas for maximum radiation within finite aperture area
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Shao-fei Wang, Yury A. Andreev
    Abstract:

    In this paper, the combined Antenna array is developed to maximize the effective potential gain ( $G_{ep}$ ) within finite aperture area for the high-power ultra-wideband (UWB) radiation. The idea is to make the Antenna Element as small as possible, so that more Elements can be arranged within the prescribed aperture area to maximize $G_{ep}$ of the UWB system. On the other hand, the Antenna Element should match the pulse excitation. This means that in the frequency domain, the working band of the Antenna Element should cover the spectrum of the radiated pulse, and in the time domain, critical parameters of the radiated field (e.g., rise time of the monopolar pulse) should not be distorted, and those can be the principles for the UWB Antenna to match the pulsed excitation, based on which the minimum size of the Antenna Element can be determined. With this method, a four-Element combined Antenna array is designed. Also, an impedance transformer and power divider are designed to feed the Antenna array. Also, a big combined Antenna is developed with the same aperture dimensions (30 cm $\times30$ cm) as the Antenna array. Then, the performances of the Antenna array and the big Antenna are measured and compared. Compared with the big Antenna, $G_{ep}$ of the Antenna array is 21% higher under the applied excitation, which indicates that the proposed method can significantly improve $G_{ep}$ of the UWB system within the prescribed aperture area. Finally, the Antenna array is furthermore optimized by adjusting the distances between the Elements, and $G_{ep}$ is improved by another 11%, the total improvement is 33%, and the corresponding effective potential gain is 1.49.

  • Optimizing High-Power Ultra-Wideband Combined Antennas for Maximum Radiation Within Finite Aperture Area
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Shao-fei Wang, Yury A. Andreev
    Abstract:

    In this paper, the combined Antenna array is developed to maximize the effective potential gain (Gep) within finite aperture area for the high-power ultra-wideband (UWB) radiation. The idea is to make the Antenna Element as small as possible, so that more Elements can be arranged within the prescribed aperture area to maximize Gep of the UWB system. On the other hand, the Antenna Element should match the pulse excitation. This means that in the frequency domain, the working band of the Antenna Element should cover the spectrum of the radiated pulse, and in the time domain, critical parameters of the radiated field (e.g., rise time of the monopolar pulse) should not be distorted, and those can be the principles for the UWB Antenna to match the pulsed excitation, based on which the minimum size of the Antenna Element can be determined. With this method, a four-Element combined Antenna array is designed. Also, an impedance transformer and power divider are designed to feed the Antenna array. Also, a big combined Antenna is developed with the same aperture dimensions (30 cm × 30 cm) as the Antenna array. Then, the performances of the Antenna array and the big Antenna are measured and compared. Compared with the big Antenna, Gep of the Antenna array is 21% higher under the applied excitation, which indicates that the proposed method can significantly improve Gep of the UWB system within the prescribed aperture area. Finally, the Antenna array is furthermore optimized by adjusting the distances between the Elements, and Gep is improved by another 11%, the total improvement is 33%, and the corresponding effective potential gain is 1.49.

Guangli Yang - One of the best experts on this subject based on the ideXlab platform.

  • high isolation 3 5 ghz eight Antenna mimo array using balanced open slot Antenna Element for 5g smartphones
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Yixin Li, Chowyen Desmond Sim, Yong Luo, Guangli Yang
    Abstract:

    A high-isolation eight-Antenna multi-input multi-output (MIMO) array operating in the 3.5 GHz band (3.4–3.6 GHz) for future smartphones is proposed. Here, a novel balanced open-slot Antenna is designed as an array Antenna Element, in which this Antenna design can yield a balanced slot mode (with reduced ground effects) that can enhance the isolation between two adjacent input ports. Furthermore, by meticulously arranging the positions of the eight Antenna Elements, desirable polarization diversity can also be successfully achieved, which further mitigates the coupling between Antenna Elements. A prototype was manufactured to validate the simulation. A good impedance matching (return loss > 10 dB), high isolation (>17.5 dB), high total efficiency (>62%), and low envelope correlation coefficient (ECC, <0.05) were measured across the desired operation bandwidth. To verify the MIMO performance, ergodic channel capacity using the Kronecker channel model was calculated. The effects of hand phantom were also studied.

  • high isolation 3 5 ghz eight Antenna mimo array using balanced open slot Antenna Element for 5g smartphones
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Chowyen Desmond Sim, Yong Luo, Guangli Yang
    Abstract:

    A high-isolation eight-Antenna multi-input multi-output (MIMO) array operating in the 3.5 GHz band (3.4–3.6 GHz) for future smartphones is proposed. Here, a novel balanced open-slot Antenna is designed as an array Antenna Element, in which this Antenna design can yield a balanced slot mode (with reduced ground effects) that can enhance the isolation between two adjacent input ports. Furthermore, by meticulously arranging the positions of the eight Antenna Elements, desirable polarization diversity can also be successfully achieved, which further mitigates the coupling between Antenna Elements. A prototype was manufactured to validate the simulation. A good impedance matching (return loss > 10 dB), high isolation (>17.5 dB), high total efficiency (>62%), and low envelope correlation coefficient (ECC, <0.05) were measured across the desired operation bandwidth. To verify the MIMO performance, ergodic channel capacity using the Kronecker channel model was calculated. The effects of hand phantom were also studied.

Shao-fei Wang - One of the best experts on this subject based on the ideXlab platform.

  • optimizing high power ultra wideband combined Antennas for maximum radiation within finite aperture area
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Shao-fei Wang, Yury A. Andreev
    Abstract:

    In this paper, the combined Antenna array is developed to maximize the effective potential gain ( $G_{ep}$ ) within finite aperture area for the high-power ultra-wideband (UWB) radiation. The idea is to make the Antenna Element as small as possible, so that more Elements can be arranged within the prescribed aperture area to maximize $G_{ep}$ of the UWB system. On the other hand, the Antenna Element should match the pulse excitation. This means that in the frequency domain, the working band of the Antenna Element should cover the spectrum of the radiated pulse, and in the time domain, critical parameters of the radiated field (e.g., rise time of the monopolar pulse) should not be distorted, and those can be the principles for the UWB Antenna to match the pulsed excitation, based on which the minimum size of the Antenna Element can be determined. With this method, a four-Element combined Antenna array is designed. Also, an impedance transformer and power divider are designed to feed the Antenna array. Also, a big combined Antenna is developed with the same aperture dimensions (30 cm $\times30$ cm) as the Antenna array. Then, the performances of the Antenna array and the big Antenna are measured and compared. Compared with the big Antenna, $G_{ep}$ of the Antenna array is 21% higher under the applied excitation, which indicates that the proposed method can significantly improve $G_{ep}$ of the UWB system within the prescribed aperture area. Finally, the Antenna array is furthermore optimized by adjusting the distances between the Elements, and $G_{ep}$ is improved by another 11%, the total improvement is 33%, and the corresponding effective potential gain is 1.49.

  • Optimizing High-Power Ultra-Wideband Combined Antennas for Maximum Radiation Within Finite Aperture Area
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Shao-fei Wang, Yury A. Andreev
    Abstract:

    In this paper, the combined Antenna array is developed to maximize the effective potential gain (Gep) within finite aperture area for the high-power ultra-wideband (UWB) radiation. The idea is to make the Antenna Element as small as possible, so that more Elements can be arranged within the prescribed aperture area to maximize Gep of the UWB system. On the other hand, the Antenna Element should match the pulse excitation. This means that in the frequency domain, the working band of the Antenna Element should cover the spectrum of the radiated pulse, and in the time domain, critical parameters of the radiated field (e.g., rise time of the monopolar pulse) should not be distorted, and those can be the principles for the UWB Antenna to match the pulsed excitation, based on which the minimum size of the Antenna Element can be determined. With this method, a four-Element combined Antenna array is designed. Also, an impedance transformer and power divider are designed to feed the Antenna array. Also, a big combined Antenna is developed with the same aperture dimensions (30 cm × 30 cm) as the Antenna array. Then, the performances of the Antenna array and the big Antenna are measured and compared. Compared with the big Antenna, Gep of the Antenna array is 21% higher under the applied excitation, which indicates that the proposed method can significantly improve Gep of the UWB system within the prescribed aperture area. Finally, the Antenna array is furthermore optimized by adjusting the distances between the Elements, and Gep is improved by another 11%, the total improvement is 33%, and the corresponding effective potential gain is 1.49.

A. J. Faulkner - One of the best experts on this subject based on the ideXlab platform.

  • skala a log periodic array Antenna for the ska low instrument design simulations tests and system considerations
    arXiv: Instrumentation and Methods for Astrophysics, 2015
    Co-Authors: Eloy De Lera Acedo, N. Troop, N. Drought, N Razavighods, A. J. Faulkner
    Abstract:

    The very demanding requirements of the SKA-low instrument call for a challenging Antenna design capable of delivering excellence performance in radiation patterns, impedance matching, polarization purity, cost, longevity, etc. This paper is devoted to the development (design and test of first prototypes) of an active ultra-wideband Antenna Element for the low-frequency instrument of the SKA radio telescope. The Antenna Element and differential low noise amplifier described here were originally designed to cover the former SKA-low band (70-450MHz) but it is now aimed to cover the re-defined SKA-low band (50-350MHz) and furthermore the Antenna is capable of performing up to 650MHz with the current design. The design is focused on maximum sensitivity in a wide field of view (+/- 45deg from zenith) and low cross-polarization ratios. Furthermore, the size and cost of the Element has to be kept to a minimum as millions of these Antennas will need to be deployed for the full SKA in very compact configurations. The primary focus of this paper is therefore to discuss various design implications for the SKA-low telescope.

  • SKALA, a log-periodic array Antenna for the SKA-low instrument: design, simulations, tests and system considerations
    Experimental Astronomy, 2015
    Co-Authors: Eloy De Lera Acedo, N. Troop, N. Drought, Nima Razavi-ghods, A. J. Faulkner
    Abstract:

    The very demanding requirements of the SKA-low instrument call for a challenging Antenna design capable of delivering excellent performance in radiation patterns, impedance matching, polarization purity, cost, longevity, etc. This paper is devoted to the development (design and test of the first prototypes) of an active ultra-wideband Antenna Element for the low-frequency instrument of the SKA radio telescope. The Antenna Element and differential low noise amplifier described here were originally designed to cover the former SKA-low band (70–450 MHz) but it is now aimed to cover the re-defined SKA-low band (50–350 MHz) and furthermore the Antenna is capable of performing up to 650 MHz with the current design. The design is focused on maximum sensitivity in a wide field of view (+/− 45° from zenith) and low cross-polarization ratios. Furthermore, the size and cost of the Element has to be kept to a minimum as millions of these Antennas will need to be deployed for the full SKA in very compact configurations. The primary focus of this paper is therefore to discuss various design implications for the SKA-low telescope.

Chowyen Desmond Sim - One of the best experts on this subject based on the ideXlab platform.

  • wideband four port mimo Antenna array with high isolation for future wireless systems
    Aeu-international Journal of Electronics and Communications, 2021
    Co-Authors: Jayshri Kulkarni, Arpan Desai, Chowyen Desmond Sim
    Abstract:

    Abstract A four-port MIMO Antenna array with wideband and high isolation characteristics for imminent wireless systems functioning in 5G New Radio (NR) sub-6GHz n77/n78/n79 and 5GHz WLAN bands is proposed. Each array Antenna Element is a microstrip-line fed monopole type. The novelty of the Antenna lies in loading an “EL” slot into the radiating Element along with two identical stubs coupled to the partial ground in order to improve the impedance matching and radiation characteristics across the bands of interest. To further attain high port isolation without affecting the compactness and radiation performance of each Antenna Element, the technique of introducing an innovative un-protruded multi-slot (UPMS) isolating Element (of low-profile 2×19 mm2) between two closely spaced Antenna Elements (with an edge-to-edge distance of approx. 0.03λ at 4.6 GHz) is also presented. Besides demonstrating a small footprint of 30×40×1.6 mm3, the proposed four-port MIMO Antenna array has also shown wide 10-dB impedance bandwidth of 58.56% (3.20-5.85 GHz), high isolation of more than 17.5 dB, and good gain and efficiency of around 3.5 dBi and 85%, respectively, across the bands of interest. Finally, the MIMO performance metrics of the proposed Antenna are also analyzed.

  • high isolation 3 5 ghz eight Antenna mimo array using balanced open slot Antenna Element for 5g smartphones
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Yixin Li, Chowyen Desmond Sim, Yong Luo, Guangli Yang
    Abstract:

    A high-isolation eight-Antenna multi-input multi-output (MIMO) array operating in the 3.5 GHz band (3.4–3.6 GHz) for future smartphones is proposed. Here, a novel balanced open-slot Antenna is designed as an array Antenna Element, in which this Antenna design can yield a balanced slot mode (with reduced ground effects) that can enhance the isolation between two adjacent input ports. Furthermore, by meticulously arranging the positions of the eight Antenna Elements, desirable polarization diversity can also be successfully achieved, which further mitigates the coupling between Antenna Elements. A prototype was manufactured to validate the simulation. A good impedance matching (return loss > 10 dB), high isolation (>17.5 dB), high total efficiency (>62%), and low envelope correlation coefficient (ECC, <0.05) were measured across the desired operation bandwidth. To verify the MIMO performance, ergodic channel capacity using the Kronecker channel model was calculated. The effects of hand phantom were also studied.

  • high isolation 3 5 ghz eight Antenna mimo array using balanced open slot Antenna Element for 5g smartphones
    IEEE Transactions on Antennas and Propagation, 2019
    Co-Authors: Chowyen Desmond Sim, Yong Luo, Guangli Yang
    Abstract:

    A high-isolation eight-Antenna multi-input multi-output (MIMO) array operating in the 3.5 GHz band (3.4–3.6 GHz) for future smartphones is proposed. Here, a novel balanced open-slot Antenna is designed as an array Antenna Element, in which this Antenna design can yield a balanced slot mode (with reduced ground effects) that can enhance the isolation between two adjacent input ports. Furthermore, by meticulously arranging the positions of the eight Antenna Elements, desirable polarization diversity can also be successfully achieved, which further mitigates the coupling between Antenna Elements. A prototype was manufactured to validate the simulation. A good impedance matching (return loss > 10 dB), high isolation (>17.5 dB), high total efficiency (>62%), and low envelope correlation coefficient (ECC, <0.05) were measured across the desired operation bandwidth. To verify the MIMO performance, ergodic channel capacity using the Kronecker channel model was calculated. The effects of hand phantom were also studied.