A. Bendaoudi, M. Berka, Mohamed Debab, Z. Mahdjoub
Abstract In this paper, a wide bandwidth (20 GHz) and small sized (200 × 200 × 50 µm3) terahertz (THz) square graphene ribbon antenna using Photonic Band Gap (PBG) substrate are investigated in the 0.6–0.8 THz band. The proposed antenna consists of graphene as radiating patch mounted on four types of ground plane. The important aim of this work is to eliminate the second resonance frequency by utilize a several types of ground plane and keep a single frequency by improving the performance of the proposed antenna. The effect of change ground plane on the performance of antenna is compared, in terms of reflection coefficient, bandwidth, directivity and radiation pattern. The antenna has achieved good gain (7.62 dB) and good directivity (6.38 dB) in comparison to work reported in the literature.
{"title":"Effects of ground plane on a square graphene ribbon patch antenna designed on a high-permittivity substrate with PBG structures","authors":"A. Bendaoudi, M. Berka, Mohamed Debab, Z. Mahdjoub","doi":"10.1515/freq-2022-0149","DOIUrl":"https://doi.org/10.1515/freq-2022-0149","url":null,"abstract":"Abstract In this paper, a wide bandwidth (20 GHz) and small sized (200 × 200 × 50 µm3) terahertz (THz) square graphene ribbon antenna using Photonic Band Gap (PBG) substrate are investigated in the 0.6–0.8 THz band. The proposed antenna consists of graphene as radiating patch mounted on four types of ground plane. The important aim of this work is to eliminate the second resonance frequency by utilize a several types of ground plane and keep a single frequency by improving the performance of the proposed antenna. The effect of change ground plane on the performance of antenna is compared, in terms of reflection coefficient, bandwidth, directivity and radiation pattern. The antenna has achieved good gain (7.62 dB) and good directivity (6.38 dB) in comparison to work reported in the literature.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"385 - 394"},"PeriodicalIF":1.1,"publicationDate":"2023-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41966966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The article presents the design and development of a metamaterial-based microwave absorber having polarisation insensitivity, broad angle of incidence, low profile, and compactness in the microwave frequency range. The unit cell focuses to achieve maximum absorption at C-, X- and broad Ku-bands. The structure is simulated and the results are analysed for different angles of polarisation and angle of incidence. The dimension of the proposed structure is ultrathin and compact having an overall dimension of 8 mm × 8 mm × 0.8 mm. The dimensions are optimized in such a fashion to achieve three different peaks at three different bands thereby making the triple-band behaviour of the metamaterial absorber possible. The structure is providing absorption of 99.14% absorption at 6.08 GHz (C-Band) while absorption of 98.29% is achieved at 9.49 GHz (X-band) and 265 MHz bandwidth with above 95% absorption from 16.57 GHz to 16.83 GHz (Ku-Band) in the microwave regime. The absorber patch is a composition of square ring patches and a central square ring annexed with triangles on four sides, the split ring providing a combinational effect witnessing the desired absorption at designated frequencies. The unit cell dimension at a lower cut-off frequency is 0.162 λlowest. The proposed structure is verified for polarisation sensitivity and has a wide angle of incidence. The structure is experimentally verified for results and is found to be in close agreement with simulated ones. The compactness of structure with the attainment of the highest form of absorption in different bands including the 265 MHz high absorption band provides the scope of applicability in various engineering applications at microwave regimes.
{"title":"Design of a compact metamaterial absorber with wide angular stability and polarisation insensitive for C, X and broad Ku band applications","authors":"Vishal Puri, H. Singh","doi":"10.1515/freq-2022-0158","DOIUrl":"https://doi.org/10.1515/freq-2022-0158","url":null,"abstract":"Abstract The article presents the design and development of a metamaterial-based microwave absorber having polarisation insensitivity, broad angle of incidence, low profile, and compactness in the microwave frequency range. The unit cell focuses to achieve maximum absorption at C-, X- and broad Ku-bands. The structure is simulated and the results are analysed for different angles of polarisation and angle of incidence. The dimension of the proposed structure is ultrathin and compact having an overall dimension of 8 mm × 8 mm × 0.8 mm. The dimensions are optimized in such a fashion to achieve three different peaks at three different bands thereby making the triple-band behaviour of the metamaterial absorber possible. The structure is providing absorption of 99.14% absorption at 6.08 GHz (C-Band) while absorption of 98.29% is achieved at 9.49 GHz (X-band) and 265 MHz bandwidth with above 95% absorption from 16.57 GHz to 16.83 GHz (Ku-Band) in the microwave regime. The absorber patch is a composition of square ring patches and a central square ring annexed with triangles on four sides, the split ring providing a combinational effect witnessing the desired absorption at designated frequencies. The unit cell dimension at a lower cut-off frequency is 0.162 λlowest. The proposed structure is verified for polarisation sensitivity and has a wide angle of incidence. The structure is experimentally verified for results and is found to be in close agreement with simulated ones. The compactness of structure with the attainment of the highest form of absorption in different bands including the 265 MHz high absorption band provides the scope of applicability in various engineering applications at microwave regimes.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"347 - 356"},"PeriodicalIF":1.1,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43665632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract A compact but very simple dual-band bandpass filter (BPF) based on just five pairs of coupled lines is designed in this paper. It can be examined using the even- and odd-mode method because of its symmetry structure. Six transmissions zeros (TZs) can be obtained and calculated by using input impedance analysis. For demonstration, a dual-band narrowband BPF example with center frequencies at 0.94 and 1.12 GHz is fabricated and measured. The 3-dB fractional bandwidths of two passbands are 2% (0.93–0.95 GHz) and 3.4% (1.1–1.14 GHz), whose frequency ratio of upper-band to lower-band is very small. The measurement results agree with the simulation results, confirming the design process.
{"title":"Compact dual-band narrowband bandpass filter with small frequency ratio","authors":"Shangjing Xi, Jianying Guo, Yannan Jiang, K. Xu","doi":"10.1515/freq-2022-0272","DOIUrl":"https://doi.org/10.1515/freq-2022-0272","url":null,"abstract":"Abstract A compact but very simple dual-band bandpass filter (BPF) based on just five pairs of coupled lines is designed in this paper. It can be examined using the even- and odd-mode method because of its symmetry structure. Six transmissions zeros (TZs) can be obtained and calculated by using input impedance analysis. For demonstration, a dual-band narrowband BPF example with center frequencies at 0.94 and 1.12 GHz is fabricated and measured. The 3-dB fractional bandwidths of two passbands are 2% (0.93–0.95 GHz) and 3.4% (1.1–1.14 GHz), whose frequency ratio of upper-band to lower-band is very small. The measurement results agree with the simulation results, confirming the design process.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42275744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shu Jiang, Hengfei Xu, Jiangling Dou, Dongquan Sun
Abstract A monopole-like stacked microstrip antenna with dual-layer patches is proposed for ultra-wideband applications. The characteristic mode analysis (CMA) is utilized and contributes to the multi-mode behavior investigation, guiding the design process. The dual-layer patches both consist of two concentric-coupled rings. The patch configuration is optimized according to the desired mode behaviors at different frequencies. Correspondingly, the three merged resonant modes, containing the modes TM01 and TM02 of the middle layer and TM01 in the top layer, effectively broaden the operation band. The measurements demonstrate that the impedance bandwidth (IBW) of the antenna reaches 4.70–10.20 GHz (73.8%) with the return loss of 10 dB and a maximum gain of 8.7 dBi. The cross-polarization level is better than −28 dB. The proposed antenna possesses a small radius of 30 mm (0.47 λ L ${lambda }_{L}$ ), and a low-profile of 5.78 mm (0.09 λ L ${lambda }_{L}$ ). λ L ${lambda }_{L}$ is the free-space wavelength at the lowest operation frequency.
{"title":"Dual-layer microstrip monopolar patch antenna with characteristic mode analysis","authors":"Shu Jiang, Hengfei Xu, Jiangling Dou, Dongquan Sun","doi":"10.1515/freq-2022-0230","DOIUrl":"https://doi.org/10.1515/freq-2022-0230","url":null,"abstract":"Abstract A monopole-like stacked microstrip antenna with dual-layer patches is proposed for ultra-wideband applications. The characteristic mode analysis (CMA) is utilized and contributes to the multi-mode behavior investigation, guiding the design process. The dual-layer patches both consist of two concentric-coupled rings. The patch configuration is optimized according to the desired mode behaviors at different frequencies. Correspondingly, the three merged resonant modes, containing the modes TM01 and TM02 of the middle layer and TM01 in the top layer, effectively broaden the operation band. The measurements demonstrate that the impedance bandwidth (IBW) of the antenna reaches 4.70–10.20 GHz (73.8%) with the return loss of 10 dB and a maximum gain of 8.7 dBi. The cross-polarization level is better than −28 dB. The proposed antenna possesses a small radius of 30 mm (0.47 λ L ${lambda }_{L}$ ), and a low-profile of 5.78 mm (0.09 λ L ${lambda }_{L}$ ). λ L ${lambda }_{L}$ is the free-space wavelength at the lowest operation frequency.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48582862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract In order to minimize antenna complexity and improve gain, a new compact size low profile SIW-cavity-based frequency reconfigurable antenna is presented for IoT, WLAN, and 5G applications. The proposed antenna miniaturization is achieved by incorporating SIW cavity using metallic vias. The reconfiguration mechanism is accomplished by etching a circular ring slot and a C-shaped slot at the top metallic layer of the substrate. The frequency switching mechanism from low to high state is provided by eight PIN diodes. The diodes are placed in a symmetrical order along circular ring slot. All the diodes are switched on simultaneously to achieve low-frequency state operation. However, the off state of the diodes shifts antenna operation from low to high-frequency state. The antenna is fabricated on a small size substrate with an overall electrical size of (0.4λ* 0.4λ).The proposed antenna resonates at frequencies 2.4, and 3.45 GHz with 220 MHz and 470 MHz bandwidth respectively in low-frequency state. In high-frequency state, the antenna resonates at 5.8 GHz with 200 MHz bandwidth. The proposed antenna achieves peak gain of 6.3, 6.7, and 5.9 dBi in the three bands, and stable radiation patterns are attained in the working frequency band of the antenna.
{"title":"SIW-cavity based frequency reconfigurable antenna for IoT, WLAN, and 5G applications","authors":"Babu Lal Sharma, Dhirendra Mathur, M. Sharma","doi":"10.1515/freq-2022-0173","DOIUrl":"https://doi.org/10.1515/freq-2022-0173","url":null,"abstract":"Abstract In order to minimize antenna complexity and improve gain, a new compact size low profile SIW-cavity-based frequency reconfigurable antenna is presented for IoT, WLAN, and 5G applications. The proposed antenna miniaturization is achieved by incorporating SIW cavity using metallic vias. The reconfiguration mechanism is accomplished by etching a circular ring slot and a C-shaped slot at the top metallic layer of the substrate. The frequency switching mechanism from low to high state is provided by eight PIN diodes. The diodes are placed in a symmetrical order along circular ring slot. All the diodes are switched on simultaneously to achieve low-frequency state operation. However, the off state of the diodes shifts antenna operation from low to high-frequency state. The antenna is fabricated on a small size substrate with an overall electrical size of (0.4λ* 0.4λ).The proposed antenna resonates at frequencies 2.4, and 3.45 GHz with 220 MHz and 470 MHz bandwidth respectively in low-frequency state. In high-frequency state, the antenna resonates at 5.8 GHz with 200 MHz bandwidth. The proposed antenna achieves peak gain of 6.3, 6.7, and 5.9 dBi in the three bands, and stable radiation patterns are attained in the working frequency band of the antenna.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"413 - 424"},"PeriodicalIF":1.1,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48281145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This article is devoted to the study of electromagnetic scattering characteristics in arid areas, and proposes environmental monitoring and improvement methods. A four-component soil dielectric model was established to study the relationship of soil dielectric constant with soil moisture and frequency. As the Monte Carlo Method combined with Gaussian spectral function was used to simulate the actual dry ground, the Sparse Matrix/Canonical Grid (SMCG) algorithm model based on the surface current equation was established to calculate the electromagnetic scattering coefficient of arid areas. To verify the correctness of the proposed algorithm, the results obtained by SMCG was compared with those calculated by Method of Moments (MOM), which showed great consistency. Many results were obtained by using the algorithm in this paper, based on the measured soil data in the southeastern area of Ejin Banner, Inner Mongolia. It was found that soil moisture content, area roughness and incident electromagnetic wave segment had influence on the scattering echo and showed regular change. The results of this paper are of guiding significance for soil moisture monitoring, desertification control and agricultural planting in arid areas.
{"title":"SMCG research on electromagnetic scattering in arid area","authors":"F. Jiang","doi":"10.1515/freq-2022-0108","DOIUrl":"https://doi.org/10.1515/freq-2022-0108","url":null,"abstract":"Abstract This article is devoted to the study of electromagnetic scattering characteristics in arid areas, and proposes environmental monitoring and improvement methods. A four-component soil dielectric model was established to study the relationship of soil dielectric constant with soil moisture and frequency. As the Monte Carlo Method combined with Gaussian spectral function was used to simulate the actual dry ground, the Sparse Matrix/Canonical Grid (SMCG) algorithm model based on the surface current equation was established to calculate the electromagnetic scattering coefficient of arid areas. To verify the correctness of the proposed algorithm, the results obtained by SMCG was compared with those calculated by Method of Moments (MOM), which showed great consistency. Many results were obtained by using the algorithm in this paper, based on the measured soil data in the southeastern area of Ejin Banner, Inner Mongolia. It was found that soil moisture content, area roughness and incident electromagnetic wave segment had influence on the scattering echo and showed regular change. The results of this paper are of guiding significance for soil moisture monitoring, desertification control and agricultural planting in arid areas.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"337 - 345"},"PeriodicalIF":1.1,"publicationDate":"2023-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46414701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract In this paper, a Decoupling Nearfield Surface (DNS) is designed above the antenna, to reduce the mutual coupling of closely two or more patch array. In this way, the electrical and magnetic distributions are utilized to demonstrate the mechanism of isolation. The proposed DNS element creates the electric field distributions with an orthogonal mode and the magnetic field distributions with excitation in substrate such that the effective suppression of antenna mutual coupling is obtained. The DNS element can be easily applied to the Multiple-Input Multiple-Output (MIMO) antennas that having multiple patch elements. Moreover, the proposed structure is implemented practically and simulated for a patched antenna. The measurement and simulation results verifies that the isolation is more than 20 dB and the isolated impedance bandwidth is about 7%.
{"title":"Mutual coupling reduction with Peyton Turtle pattern nearfield surface for MIMO patch antenna","authors":"Alireza Omidvar, P. Rezaei, E. Atashpanjeh","doi":"10.1515/freq-2022-0150","DOIUrl":"https://doi.org/10.1515/freq-2022-0150","url":null,"abstract":"Abstract In this paper, a Decoupling Nearfield Surface (DNS) is designed above the antenna, to reduce the mutual coupling of closely two or more patch array. In this way, the electrical and magnetic distributions are utilized to demonstrate the mechanism of isolation. The proposed DNS element creates the electric field distributions with an orthogonal mode and the magnetic field distributions with excitation in substrate such that the effective suppression of antenna mutual coupling is obtained. The DNS element can be easily applied to the Multiple-Input Multiple-Output (MIMO) antennas that having multiple patch elements. Moreover, the proposed structure is implemented practically and simulated for a patched antenna. The measurement and simulation results verifies that the isolation is more than 20 dB and the isolated impedance bandwidth is about 7%.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"395 - 401"},"PeriodicalIF":1.1,"publicationDate":"2023-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49205632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The paper presents a dualband and compact antipodal Vivaldi antenna (AVA) array by using a dielectric lens (DL) and corrugations for 5G applications. The proposed novel antenna provides very high efficiency and it alleviates beam titling very effectively. Its efficiency is in the range of 95.93%–97.52% whereas the H plane beam titling is ± 1 ° $pm 1{}^{circ}$ over most of the frequency range. The antenna frequency response is improved by incorporating corrugations which results in the antenna miniaturization. The designed AVA array size is 2.86 × 3.58 × 0.06 λ g 3 ${{lambda }_{g}}^{3}$ (for lower guided frequency). The proposed dualband antenna operates from 24.17 GHz to 29.37 GHz and 30.76 GHz to 40.58 GHz. These frequency bands cover 28 GHz and 38 GHz bands of 5G communications. Next, the front-to-back ratio is improved significantly which further results in the gain enhancement. Also, the grooves in the feeding network minimize reverse power reflections. The radiation pattern is stable and it shows that the designed antenna is a directional antenna. The antenna is designed, simulated, and tested by using a network analyzer and anechoic chamber. The testing and simulated results indicate that the proposed AVA array is the best candidate to integrate it in 5G devices.
{"title":"A corrugated and lens based miniaturized antipodal Vivaldi antenna for 28 GHz and 38 GHz bands applications","authors":"Amruta S. Dixit, Sumit Kumar, M. Abegaonkar","doi":"10.1515/freq-2022-0199","DOIUrl":"https://doi.org/10.1515/freq-2022-0199","url":null,"abstract":"Abstract The paper presents a dualband and compact antipodal Vivaldi antenna (AVA) array by using a dielectric lens (DL) and corrugations for 5G applications. The proposed novel antenna provides very high efficiency and it alleviates beam titling very effectively. Its efficiency is in the range of 95.93%–97.52% whereas the H plane beam titling is ± 1 ° $pm 1{}^{circ}$ over most of the frequency range. The antenna frequency response is improved by incorporating corrugations which results in the antenna miniaturization. The designed AVA array size is 2.86 × 3.58 × 0.06 λ g 3 ${{lambda }_{g}}^{3}$ (for lower guided frequency). The proposed dualband antenna operates from 24.17 GHz to 29.37 GHz and 30.76 GHz to 40.58 GHz. These frequency bands cover 28 GHz and 38 GHz bands of 5G communications. Next, the front-to-back ratio is improved significantly which further results in the gain enhancement. Also, the grooves in the feeding network minimize reverse power reflections. The radiation pattern is stable and it shows that the designed antenna is a directional antenna. The antenna is designed, simulated, and tested by using a network analyzer and anechoic chamber. The testing and simulated results indicate that the proposed AVA array is the best candidate to integrate it in 5G devices.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47372527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}