X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Walter de Gruyter GmbH  (8)
Type of Medium
Publisher
  • Walter de Gruyter GmbH  (8)
Person/Organisation
Language
Years
Subjects(RVK)
  • 1
    Online Resource
    Online Resource
    Compact super-wideband MIMO antenna with improved isolation for wireless communications
    Walter de Gruyter GmbH ; 2021
    In:  Frequenz Vol. 75, No. 9-10 ( 2021-10-26), p. 407-417
    Details
    In: Frequenz, Walter de Gruyter GmbH, Vol. 75, No. 9-10 ( 2021-10-26), p. 407-417
    Abstract: This paper presents a miniaturized dual-element Super-Wideband (SWB) Multiple-Input-Multiple-Output (MIMO) antenna. The operation bandwidth is enhanced by 175% with a Bandwidth Dimension Ratio (BDR) of 6960, using a tapered microstrip line and employing an improved isolation technique. An inverted T-slot is used in the partial ground plane of the antenna. Isolation is increased up to 25 dB over the operating band (1.6–24.5 GHz) by using a pair of T-shaped stubs and a rectangular strip between them. A detailed analysis of the parameters Envelope Correlation Coefficient (ECC), Diversity Gain (DG), Mean Effective Gain (MEG), Total Active Reflection Coefficient (TARC), isolation between the ports, and Channel Capacity Loss (CCL) is undertaken to investigate the performance of proposed SWB MIMO antenna. A prototype of the proposed design is developed by fabricating on the FR–4 (loss tangent 0.02) dielectric substrate of electrical dimension 0.18 λ 0  × 0.14 λ 0 . The measured parameters are in good agreement with the simulated ones. The proposed antenna focusses on 2.4–2.483 GHz frequency band (Bluetooth) and 3.4–3.6 GHz frequency band with a center frequency of 3.5 GHz (as part of the sub 6 GHz 5G band).
    Type of Medium: Online Resource
    ISSN: 0016-1136 , 2191-6349
    URL: Article
    DOI: 10.1515/freq-2020-0213
    RVK:
    ZG 1100
    Language: English
    Publisher: Walter de Gruyter GmbH
    Publication Date: 2021
    detail.hit.zdb_id: 2423831-4
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 2
    Online Resource
    Online Resource
    A wideband metamaterial cross polarizer conversion for C and X band applications
    Walter de Gruyter GmbH ; 2022
    In:  Frequenz Vol. 76, No. 1-2 ( 2022-01-27), p. 63-74
    Details
    In: Frequenz, Walter de Gruyter GmbH, Vol. 76, No. 1-2 ( 2022-01-27), p. 63-74
    Abstract: This article present wideband Metamaterial Cross Polarizer (MCP) structure for C and X band applications. The proposed structure consists of wheel shaped associated with meander line and triangular shaped patches having overall dimension of 18 × 18 mm. The anisotropic design patchis a single metallic layer (Cu) placed at the top of dielectric substrate FR-4 and backed by a ground also consists of metal layer (Cu). A wideband Polarization Conversion Ratio (PCR) above 0.8 magnitudes is achieved having bandwidth of 8.1 GHz ranging from 3.43 to 11.53 GHz and it works for C (4–8 GHz) and X (8–12 GHz) band approximately. The bandwidth of PCR at Full Width Half Maxima (FWHM) achieved is 8.24 GHz (3.60–11.84 GHz). Three distinct PCR peaks are observed at 4.2, 5.98, and 9.46 GHz with PCR magnitudes at 91.07, 96.39, and 99.76% respectively. Analysis of polarization conversion phenomena at these three frequencies is described with the help of current and electric field distribution. The proposed anisotropic structure is examined at different angles under normal and oblique incident. The simulation is performed through ANSYS HFSS (19.1), fabrication is done on substrate FR-4 using printed circuit board (PCB). The simulated and measured curves obtained for reflection coefficient and PCR are similar to one another with minute difference due to fabrication tolerances.
    Type of Medium: Online Resource
    ISSN: 0016-1136 , 2191-6349
    URL: Article
    DOI: 10.1515/freq-2021-0033
    RVK:
    ZG 1100
    Language: English
    Publisher: Walter de Gruyter GmbH
    Publication Date: 2022
    detail.hit.zdb_id: 2423831-4
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 3
    Online Resource
    Online Resource
    Dual circular slot ring triple-band MIMO antenna for 5G applications
    Walter de Gruyter GmbH ; 2021
    In:  Frequenz Vol. 75, No. 3-4 ( 2021-03-26), p. 91-100
    Details
    In: Frequenz, Walter de Gruyter GmbH, Vol. 75, No. 3-4 ( 2021-03-26), p. 91-100
    Abstract: A Triple-band Multiple-Input-Multiple-Output (MIMO) antenna for 5G mobile terminal applications is proposed in this paper. The design comprises four-port/two resonators, each having two concentric circular slot ring radiators etched on a ground plane of size 50 mm  × ${\times}$  50 mm. The antenna is fed by perpendicularly arranged 50 Ω microstrip line feeds on the top layer. Decoupling techniques were used to suppress mutual coupling between the two resonators. The perpendicular arrangement of the feed lines and port reduces mutual coupling between the two ports and increases isolation. The antenna operates in multiple bands: 3.35–3.69 GHz, 24–28 GHz, and 37–40 GHz frequency range with central frequencies at 3.5 GHz, 26 GHz, and 38 GHz, respectively allocated for 5G. The antenna provides a gain of 2.7–7.8 dB and a radiation efficiency of 0.49–0.85 in the operating bands. Diversity performance is studied in terms of the Envelop Correlation Coefficient (ECC), Diversity Gain (DG), and Total Active Reflection Coefficient (TARC) were found to be less than 0.01, greater than 9.99 dB, and less than −10 dB respectively. The proposed antenna offers good S-parameters, voltage standing wave ratio (VSWR), TARC, radiation pattern, high gain, and low ECC. The antenna was fabricated and tested. The measured results and simulated results are in good agreement. It possesses sufficient potential for 5G mobile terminal and smart wearable applications.
    Type of Medium: Online Resource
    ISSN: 2191-6349 , 0016-1136
    URL: Article
    DOI: 10.1515/freq-2020-0138
    RVK:
    ZG 1100
    Language: English
    Publisher: Walter de Gruyter GmbH
    Publication Date: 2021
    detail.hit.zdb_id: 2423831-4
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 4
    Online Resource
    Online Resource
    A circular monopole antenna with uniquely packed quad T-shaped strips for WLAN/WiMAX application
    Walter de Gruyter GmbH ; 2023
    In:  Frequenz Vol. 77, No. 3-4 ( 2023-04-25), p. 211-218
    Details
    In: Frequenz, Walter de Gruyter GmbH, Vol. 77, No. 3-4 ( 2023-04-25), p. 211-218
    Abstract: This paper presents a circular monopole antenna with uniquely packed quad T-shaped strips etched on FR4 epoxy substrate having material permittivity 4.4, loss tangent 0.02, and thickness 1.6 mm. The 3.5 GHz band is achieved through this arrangement, which has return loss less than −10 dB while maintaining VSWR 〈 2. It provides a peak gain of 2.65 dBi at 3.5 GHz and average gain of 2.52 dBi in the entire operating frequency band. The radiation pattern is almost omnidirectional in E plane and bidirectional in H plane. The proposed antenna has a compact size of 41.25 mm × 30.55 mm. The simulated results of S11 parameters, gain, VSWR, radiation pattern, and efficiency are studied and verified with the measured results of fabricated antenna as well as its equivalent lumped circuit model. Investigation shows that the proposed antenna can be employed for WLAN/WiMAX applications efficiently.
    Type of Medium: Online Resource
    ISSN: 0016-1136 , 2191-6349
    URL: Article
    DOI: 10.1515/freq-2022-0017
    RVK:
    ZG 1100
    Language: English
    Publisher: Walter de Gruyter GmbH
    Publication Date: 2023
    detail.hit.zdb_id: 2423831-4
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 5
    Online Resource
    Online Resource
    Circular shape monopole antenna with modified ground plane proclaiming SWB characteristics
    Walter de Gruyter GmbH ; 2023
    In:  Frequenz Vol. 77, No. 5-6 ( 2023-06-27), p. 303-313
    Details
    In: Frequenz, Walter de Gruyter GmbH, Vol. 77, No. 5-6 ( 2023-06-27), p. 303-313
    Abstract: Modern communication systems require an antenna with miniaturized size and large bandwidth with high data rate. In this article, a circular monopole antenna is presented with hexagonal patch on both sides of microstrip feedline and an I- shaped rectangular slot etched at the center of feedline to provide impedance matching. The modified loaded ground reduces the coupling between ground plane and radiation patch. This antenna has compact dimension of 30 mm × 25 mm with electrical size of 0.25 λ  × 0.20 λ. This antenna has been designed and simulated in HFSS commercial software and fabricated on FR4 substrate of thickness 1.6 mm with relative permittivity 4.4, loss tangent of 0.02. The experimental results are compared with simulated one, which are in close agreement. It attains a frequency band ranging from 2.4 to 56.6 GHz with reflection coefficient 〈 −10, percentage bandwidth of 183.72%, Bandwidth Ratio (BR) 23.58:1, and Bandwidth Dimension Ratio (BDR) of 3674.40. The peak gain and radiation efficiency of this antenna is 12.77 dBi and 98.82% at 45.84 and 5.6 GHz respectively. Time domain analysis has been done, which proclaims that the proposed antenna has SWB characteristics. It may be useful for high data rate transmission, medical imaging, and other SWB applications.
    Type of Medium: Online Resource
    ISSN: 0016-1136 , 2191-6349
    URL: Article
    DOI: 10.1515/freq-2022-0087
    RVK:
    ZG 1100
    Language: English
    Publisher: Walter de Gruyter GmbH
    Publication Date: 2023
    detail.hit.zdb_id: 2423831-4
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 6
    Online Resource
    Online Resource
    DGS based miniaturized wideband MIMO antenna with efficient isolation for C band applications
    Walter de Gruyter GmbH ; 2023
    In:  Frequenz Vol. 77, No. 3-4 ( 2023-04-25), p. 163-172
    Details
    In: Frequenz, Walter de Gruyter GmbH, Vol. 77, No. 3-4 ( 2023-04-25), p. 163-172
    Abstract: A wideband multiple-input multiple-output (MIMO) antenna for C-band applications is presented in this paper. It consists of 2  × ${\times}$  1 hexagonal motifs which serves as radiating elements. The side of each hexagonal element is 5.73 mm and the overall dimension of the proposed MIMO antenna is 30  × ${\times}$  20  × ${\times}$  1.6 mm 3 . The hexagonal motifs are embedded on inexpensive FR-4 lossy substrate. Thereafter, a circle with radius 1 mm is etched at the center of each hexagonal motif. Inverted L-shaped stubs are employed to attain efficient isolation between the nearby antenna elements. Four inverted L-shaped stubs are included to further enhance the isolation and eliminate the antenna size increment simultaneously, by suppressing the surface waves. Before using the decoupling approach, the MIMO antenna had an impedance bandwidth of 6.7 GHz and an isolation of −20 dB. The suggested antenna’s impedance bandwidth and isolation are 5.83 GHz and −52 dB, respectively, after using a decoupling approach (inverted L-shaped stub). The proposed MIMO antenna had a peak gain and radiation efficiency of 3–7 dBi and better than 90% (with decoupling), 2.75 to 6 dBi and greater than 60% (without decoupling). To verify the proposed design, a prototype was developed to compare the simulated parameters with the measured one. The envelope correlation coefficient (ECC) was less than 0.05, and channel capacity loss (CCL) less than 0.3 was achieved with DGS. Besides, scattering matrix such as return loss S 11 and transmission coefficient S 21 between two elements, radiation pattern, and current distribution was also favorable. Thus, the proposed MIMO antenna is advantageous to be used for C-band applications such as developing new generation air-borne and space-borne radars, as well as X-band applications.
    Type of Medium: Online Resource
    ISSN: 0016-1136 , 2191-6349
    URL: Article
    DOI: 10.1515/freq-2022-0029
    RVK:
    ZG 1100
    Language: English
    Publisher: Walter de Gruyter GmbH
    Publication Date: 2023
    detail.hit.zdb_id: 2423831-4
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 7
    Online Resource
    Online Resource
    Linear-to-linear polarization conversion using metasurface for X, Ku and K band applications
    Walter de Gruyter GmbH ; 2022
    In:  Frequenz Vol. 76, No. 7-8 ( 2022-08-26), p. 461-470
    Details
    In: Frequenz, Walter de Gruyter GmbH, Vol. 76, No. 7-8 ( 2022-08-26), p. 461-470
    Abstract: Ultra thin wideband metasurface polarization converter is presented in this paper. The proposed structure is used for linear conversion i.e., X polarized to Y polarized and vice versa. The design of the structure consists of stair case shaped and is fabricated on FR-4 substrate having overall dimension of 3 mm × 3 mm. The Polarization Conversion Ratio (PCR) obtained is wideband having bandwidth of 10.81 GHz (10.57–21.38 GHz) above 89%. Two distinct peaks are observed in the range of interest having frequencies at 11.66 and 18.13 GHz with maximum magnitude of 99.30 and 99.90%. These two peaks occur due to plasmonic resonance. At these two peaks, surface current distribution is plotted to explain the wideband response from the structure. The structure is simulated using commercially available ANSYS HFSS 19.1 and measured inside an anechoic chamber with the help of Vector Network Analyser (VNA). The proposed structure find applications for X (8–12 GHz), Ku (18–21 GHz) and K (21–27 GHz) band. At last the structure is measured with already reported polarization converters and find practical applications for frequency reconfigurable antennas, linearly conversion of incident waves, etc.
    Type of Medium: Online Resource
    ISSN: 0016-1136 , 2191-6349
    URL: Article
    DOI: 10.1515/freq-2021-0204
    RVK:
    ZG 1100
    Language: English
    Publisher: Walter de Gruyter GmbH
    Publication Date: 2022
    detail.hit.zdb_id: 2423831-4
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 8
    Online Resource
    Online Resource
    A compact quad element MIMO antenna for LTE/5G (sub-6 GHz) applications
    Walter de Gruyter GmbH ; 2023
    In:  Frequenz Vol. 77, No. 3-4 ( 2023-04-25), p. 173-183
    Details
    In: Frequenz, Walter de Gruyter GmbH, Vol. 77, No. 3-4 ( 2023-04-25), p. 173-183
    Abstract: In this paper, a compact I shaped monopole radiator with a dimension of 24 × 22 × 1.6 mm 3 is proposed. The monopole radiator achieved an impedance bandwidth of 1.46 GHz (4.06–5.52 GHz) using partial ground plane. Further to cover the sub-6 GHz spectrum (3.4–3.6 GHz) for future 5G communications, a four-element multi-input multi-output (MIMO) antenna configuration is designed by utilizing the single element antenna. The operation bandwidth of 2.27 GHz (3.37–5.64 GHz) is enhanced by using a tapered microstrip feed line. Isolation is increased upto 40 dB over the operating band (3.37–5.64 GHz) by using a modified rectangular stub in the partial ground plane. This stub also provides a decoupling path and consequently limited amount of current couples to the neighbouring element due to surface waves. The modified stub suppress the surface waves and the near fields reducing the coupling between the antennas keeping it below −10 dB for the whole desired frequency range. Therefore, the proposed MIMO antenna achieved wide bandwidth of (3.37–5.64 GHz) and minimum isolation between antenna elements 1 & 4 is −10 dB in 3.4–3.6 GHz frequency band, whereas −15 dB between 3.8 and 5.64 GHz frequency band. The suggested MIMO antenna is designed on a FR4 substrate with a dielectric constant of 4.4 and a loss tangent of 0.02 and a 0.45 λ 0  × 0.45 λ 0 dimension. In terms of the envelope correlation coefficient (ECC), diversity gain (DG), mean effective gain (MEG), total active reflection coefficient (TARC), isolation between the ports, and channel capacity loss (CCL), the proposed antenna’s diversity performance characteristics are investigated and the obtained values are 0.04, 9.98, ±3, −11, −15 dB, 0.10 bits/s/Hz respectively. The antenna prototypes have been fabricated, and the measurements and simulations have been found to be in close agreement. Therefore, the proposed MIMO antenna covers n77/n78/n79 for 5G (sub-6 GHz) and LTE bands of 42/43/46.
    Type of Medium: Online Resource
    ISSN: 0016-1136 , 2191-6349
    URL: Article
    DOI: 10.1515/freq-2022-0028
    RVK:
    ZG 1100
    Language: English
    Publisher: Walter de Gruyter GmbH
    Publication Date: 2023
    detail.hit.zdb_id: 2423831-4
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
Nothing or not found what you are looking for? Please check your search query or use the Interlibrary Loan Search.
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages