Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366106
C. Parini, R. Dubrovka, S. Gregson
This paper presents the results of a recent computational electromagnetic (CEM) simulation campaign for a single offset reflector CATR, where a number of models employing different field propagation methods were compared and contrasted both qualitatively and quantitatively using objective, non-local statistical image classification techniques.
{"title":"Compact range quiet zone modelling: Quantitative assessment using a variety of electromagnetic simulation methods","authors":"C. Parini, R. Dubrovka, S. Gregson","doi":"10.1109/LAPC.2015.7366106","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366106","url":null,"abstract":"This paper presents the results of a recent computational electromagnetic (CEM) simulation campaign for a single offset reflector CATR, where a number of models employing different field propagation methods were compared and contrasted both qualitatively and quantitatively using objective, non-local statistical image classification techniques.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130587282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366107
S. Hamid, Britta Karnbach, H. Shakhtour, D. Heberling
Design and characterization of a multilayer structure consisting of stacked frequency selective surfaces (FSS) combined with a patterned laminate absorber is presented. The FSS part is a higher order bandpass filter that operates in the C-band, namely from 5 GHz to 6 GHz. Its higher order response is achieved through the stacking of capacitive-inductive-capacitive layers to maintain the low-profile structure. The patterned absorber is glued on one side of the FSS so that the resulting structure is capable of absorbing signals in the X-band (receiving mode). The prototype has been fabricated using Taconic RF-35 substrates and Eccosorb SF for the FSS and absorber parts, respectively. It has a dimension of 24.5 cm × 24.5 cm with a thickness of 0.65 cm. The measurement has been done using free space method. The transmission loss in the passband is less than 1 dB and the roll-off slope is more than 65 dB/octave. The absorption band, characterized by its low reflection and transmission response (less than -10 dB), covers the range from 8.26 GHz to more than 12 GHz. These specifications make this prototype a promising candidate for a planar radome absorber application.
{"title":"Thin multilayer frequency selective surface absorber with wide absorption response","authors":"S. Hamid, Britta Karnbach, H. Shakhtour, D. Heberling","doi":"10.1109/LAPC.2015.7366107","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366107","url":null,"abstract":"Design and characterization of a multilayer structure consisting of stacked frequency selective surfaces (FSS) combined with a patterned laminate absorber is presented. The FSS part is a higher order bandpass filter that operates in the C-band, namely from 5 GHz to 6 GHz. Its higher order response is achieved through the stacking of capacitive-inductive-capacitive layers to maintain the low-profile structure. The patterned absorber is glued on one side of the FSS so that the resulting structure is capable of absorbing signals in the X-band (receiving mode). The prototype has been fabricated using Taconic RF-35 substrates and Eccosorb SF for the FSS and absorber parts, respectively. It has a dimension of 24.5 cm × 24.5 cm with a thickness of 0.65 cm. The measurement has been done using free space method. The transmission loss in the passband is less than 1 dB and the roll-off slope is more than 65 dB/octave. The absorption band, characterized by its low reflection and transmission response (less than -10 dB), covers the range from 8.26 GHz to more than 12 GHz. These specifications make this prototype a promising candidate for a planar radome absorber application.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"259 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133697721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366024
Niels Koch
For high speed digital data connection such as WiMAX or WLAN, a good signal to noise ratio (S/N) is required. One way to keep up a good S/N-value while moving is the use of high gain antennas with a directive antenna beam. However, often there is insufficient room to place high gain antennas in a vehicle. On top if this, it is becoming increasingly difficult and more packed in the car, so that progressive antenna approaches are enforced. As a vehicle can move towards and away from the transmitter site in any azimuth angle, the antenna shall offer some omni-directionality. In this paper, an antenna for 2.45 GHz WLAN is described. It is very thin of 4 mm, and it offers 12 dBi antenna gain with almost omni-directional but very beneficial radiation characteristics with "rabbit-ear" shaped double-lobes. Moreover it can be easily implemented into the plastic spoiler on a hatchback vehicle. Experiments proof that this flat WLAN antenna structure in a spoiler outperforms monopoles and patch antennas on rooftop in any respect. When tuning to the right frequency, this antenna is ideally suited for Car2X-applications and Wireless Internet utilization such as WiMAX and WLAN.
{"title":"Vehicular spoiler antenna for high data rate WLAN","authors":"Niels Koch","doi":"10.1109/LAPC.2015.7366024","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366024","url":null,"abstract":"For high speed digital data connection such as WiMAX or WLAN, a good signal to noise ratio (S/N) is required. One way to keep up a good S/N-value while moving is the use of high gain antennas with a directive antenna beam. However, often there is insufficient room to place high gain antennas in a vehicle. On top if this, it is becoming increasingly difficult and more packed in the car, so that progressive antenna approaches are enforced. As a vehicle can move towards and away from the transmitter site in any azimuth angle, the antenna shall offer some omni-directionality. In this paper, an antenna for 2.45 GHz WLAN is described. It is very thin of 4 mm, and it offers 12 dBi antenna gain with almost omni-directional but very beneficial radiation characteristics with \"rabbit-ear\" shaped double-lobes. Moreover it can be easily implemented into the plastic spoiler on a hatchback vehicle. Experiments proof that this flat WLAN antenna structure in a spoiler outperforms monopoles and patch antennas on rooftop in any respect. When tuning to the right frequency, this antenna is ideally suited for Car2X-applications and Wireless Internet utilization such as WiMAX and WLAN.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133949905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366051
M. Ahmad, M. Amin, T. Malik, M. B. Akhtar, A. Khan, A. Akbar
In this work, input characteristics of Quadrifilar Helix Antenna (QHA) are investigated for variations in height in the presence of finite metallic structures of varying sizes. It is noticed that the input characteristics such as conductance, susceptance and reflection coefficient are affected as height of QHA above these finite metallic ground planes varies. Rapid variations are observed if QHA is placed below 0.2 λ above ground plane. Conductance, susceptance and reflection coefficient of input feed point are inversely proportional to the distance between QHA and ground plane. If the height of QHA is greater than 0.2 λ above ground plane, these parameters are relatively insensitive with respect to changes in height. Larger sizes of ground planes severely affect conductance and susceptance while the effects of smaller sizes of ground planes on input reflection coefficient are significant. Deployment above 0.2 λ at decks of LEO satellites, aerial drones and handheld mobile devices results in stable input characteristics of QHA that eventually conclude to better performance.
{"title":"Variations in input characteristics of Quadrifilar Helix Antenna due to finite metallic plain structures","authors":"M. Ahmad, M. Amin, T. Malik, M. B. Akhtar, A. Khan, A. Akbar","doi":"10.1109/LAPC.2015.7366051","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366051","url":null,"abstract":"In this work, input characteristics of Quadrifilar Helix Antenna (QHA) are investigated for variations in height in the presence of finite metallic structures of varying sizes. It is noticed that the input characteristics such as conductance, susceptance and reflection coefficient are affected as height of QHA above these finite metallic ground planes varies. Rapid variations are observed if QHA is placed below 0.2 λ above ground plane. Conductance, susceptance and reflection coefficient of input feed point are inversely proportional to the distance between QHA and ground plane. If the height of QHA is greater than 0.2 λ above ground plane, these parameters are relatively insensitive with respect to changes in height. Larger sizes of ground planes severely affect conductance and susceptance while the effects of smaller sizes of ground planes on input reflection coefficient are significant. Deployment above 0.2 λ at decks of LEO satellites, aerial drones and handheld mobile devices results in stable input characteristics of QHA that eventually conclude to better performance.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130408614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366021
A. Harmouch, H. Haddad, M. Ziade, A. El Sayed Ahmad, M. Kenaan
Conventional slotted waveguide antennas are well known and prominently used for many military and even marketable applications. This is due to their different advantageous electrical and mechanical characteristics. It is also well known that this type of antennas is a typical array of slots with which the width of the main beam can be controlled in only one plane by using a different number of elements in such antennas. Numerous research, discuss the capability of using an array of such antennas in order to narrow down the main beam in both planes and even achieve a scanning phased array. In this paper, a new and broader approach is presented concerning beam width control of the typical configuration of such antennas. This work presents the ability to control the main lobe in both planes using only one slotted waveguide to a certain extent. Different simulation results are considered at the 2.4GHz frequency demonstrating improved effectiveness in terms of directivity and high gain as well as minimizing the side-lobe level and mechanically controlling the main lobe of the antenna.
{"title":"Double-plane beamwidth control of conventional rectangular waveguide antennas using curved slotted surfaces","authors":"A. Harmouch, H. Haddad, M. Ziade, A. El Sayed Ahmad, M. Kenaan","doi":"10.1109/LAPC.2015.7366021","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366021","url":null,"abstract":"Conventional slotted waveguide antennas are well known and prominently used for many military and even marketable applications. This is due to their different advantageous electrical and mechanical characteristics. It is also well known that this type of antennas is a typical array of slots with which the width of the main beam can be controlled in only one plane by using a different number of elements in such antennas. Numerous research, discuss the capability of using an array of such antennas in order to narrow down the main beam in both planes and even achieve a scanning phased array. In this paper, a new and broader approach is presented concerning beam width control of the typical configuration of such antennas. This work presents the ability to control the main lobe in both planes using only one slotted waveguide to a certain extent. Different simulation results are considered at the 2.4GHz frequency demonstrating improved effectiveness in terms of directivity and high gain as well as minimizing the side-lobe level and mechanically controlling the main lobe of the antenna.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124919908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366077
H. Shakhtour, D. Heberling
This paper analyses the effect of noisy near-field amplitude data on the phase retrieval algorithm. Additive white Gaussian noise is applied on the signal. Signal-to-noise ratios between 3 dB and 60 dB are considered. It'll be shown that using the Iterative Fourier Transform the far-field data can be obtained even under low signal-to-noise ratio.
{"title":"Phase-less planar near-field antenna measurements: Noise analysis","authors":"H. Shakhtour, D. Heberling","doi":"10.1109/LAPC.2015.7366077","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366077","url":null,"abstract":"This paper analyses the effect of noisy near-field amplitude data on the phase retrieval algorithm. Additive white Gaussian noise is applied on the signal. Signal-to-noise ratios between 3 dB and 60 dB are considered. It'll be shown that using the Iterative Fourier Transform the far-field data can be obtained even under low signal-to-noise ratio.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124956959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366042
T. Tuovinen, M. Berg, E. Salonen
The present paper proposes an on-body antenna for wearable sensor nodes/wireless body area networks (WBANs) at 10 GHz. The radiator configuration follows the recently introduced new antenna design philosophy where electronics are embedded inside the antenna. The suggested sensor node antenna structure has a low total profile of λ/3 in the x- and y-directions and λ/5 in the z-direction. The antenna radiator is designed by maintaining pure normal polarization with a body surface and omnidirectional radiation pattern in the tangential plane of a body.
{"title":"Low-profile on-body communication antenna configuration with embedded electronics inside","authors":"T. Tuovinen, M. Berg, E. Salonen","doi":"10.1109/LAPC.2015.7366042","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366042","url":null,"abstract":"The present paper proposes an on-body antenna for wearable sensor nodes/wireless body area networks (WBANs) at 10 GHz. The radiator configuration follows the recently introduced new antenna design philosophy where electronics are embedded inside the antenna. The suggested sensor node antenna structure has a low total profile of λ/3 in the x- and y-directions and λ/5 in the z-direction. The antenna radiator is designed by maintaining pure normal polarization with a body surface and omnidirectional radiation pattern in the tangential plane of a body.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127837969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366088
Tae-Woo Kim, Kyung Choi, Hee‐Yong Hwang
In this paper, A miniaturized monopole UWB antenna with λ/4 meander slot line is presented. To achieve a considerable miniaturized antenna, a reference bowtie monopole antenna was simplified using the perfect magnetic wall condition. Also, to obtain rejection characteristic at the interference bandwidth of 5 GHz-WLAN, a meander shaped slot line was inserted at ground patch. In comparison with reference antenna, the proposed bowtie monopole antenna is about 18.5% in size.
{"title":"Small bowtie monopole UWB antenna","authors":"Tae-Woo Kim, Kyung Choi, Hee‐Yong Hwang","doi":"10.1109/LAPC.2015.7366088","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366088","url":null,"abstract":"In this paper, A miniaturized monopole UWB antenna with λ/4 meander slot line is presented. To achieve a considerable miniaturized antenna, a reference bowtie monopole antenna was simplified using the perfect magnetic wall condition. Also, to obtain rejection characteristic at the interference bandwidth of 5 GHz-WLAN, a meander shaped slot line was inserted at ground patch. In comparison with reference antenna, the proposed bowtie monopole antenna is about 18.5% in size.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117003543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366034
C. Davenport, J. Rigelsford
This paper presents simulation and measurement results of a corrugated comb reflection frequency selective surface (CR-FSS). Surface parameters are altered to investigate the effect of sloping the comb elements to produce a corrugated structure. It is proposed that the strength of such elements can therefore be increased, however the effect on the reduction in specular scatter is unknown. CST simulations and measurement results on foam and foil prototypes provide evidence that increasing the slope angle can alter scattering performance. Furthermore, issues with manufacture and the application of such surfaces are discussed.
{"title":"Corrugated comb frequency selective surfaces for control of wireless propagation in buildings","authors":"C. Davenport, J. Rigelsford","doi":"10.1109/LAPC.2015.7366034","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366034","url":null,"abstract":"This paper presents simulation and measurement results of a corrugated comb reflection frequency selective surface (CR-FSS). Surface parameters are altered to investigate the effect of sloping the comb elements to produce a corrugated structure. It is proposed that the strength of such elements can therefore be increased, however the effect on the reduction in specular scatter is unknown. CST simulations and measurement results on foam and foil prototypes provide evidence that increasing the slope angle can alter scattering performance. Furthermore, issues with manufacture and the application of such surfaces are discussed.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130179943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366136
A. Khatun, K. Haneda, M. Heino, Linsheng Li, P. Kyosti, Ruiyuan Tian
This paper discusses the feasibility of two multi-probe over-the-air antenna test methods at frequencies higher than 6 GHz. The two methods considered in this paper are prefaded signals synthesis (PFS) and plane wave synthesis (PWS) methods. Both methods suffer from huge challenges of the large number of dual-polarized probes required in emulating realistic standing waves in the antenna test zone, because physically small antennas become electrically large at the higher frequencies. However, the PFS method can take advantage of the nature of radio propagation channels at the higher frequencies, i.e., the sparsity of multipath channels and their angular selectivity, in order to reduce the number of active probes and hence signal feeds from a fading emulator. In contrast, the PWS method always needs signal feeds to all the probes and hence the implementation complexity is not reduced even under sparse multipath channels. The required number of probes is derived for the two methods using heuristic theoretical analyses and through practical antenna examples on a mobile-phone-sized ground plane at 5, 15, 30 and 60 GHz.
{"title":"Feasibility of multi-probe over-the-air antenna test methods for frequencies above 6 GHz","authors":"A. Khatun, K. Haneda, M. Heino, Linsheng Li, P. Kyosti, Ruiyuan Tian","doi":"10.1109/LAPC.2015.7366136","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366136","url":null,"abstract":"This paper discusses the feasibility of two multi-probe over-the-air antenna test methods at frequencies higher than 6 GHz. The two methods considered in this paper are prefaded signals synthesis (PFS) and plane wave synthesis (PWS) methods. Both methods suffer from huge challenges of the large number of dual-polarized probes required in emulating realistic standing waves in the antenna test zone, because physically small antennas become electrically large at the higher frequencies. However, the PFS method can take advantage of the nature of radio propagation channels at the higher frequencies, i.e., the sparsity of multipath channels and their angular selectivity, in order to reduce the number of active probes and hence signal feeds from a fading emulator. In contrast, the PWS method always needs signal feeds to all the probes and hence the implementation complexity is not reduced even under sparse multipath channels. The required number of probes is derived for the two methods using heuristic theoretical analyses and through practical antenna examples on a mobile-phone-sized ground plane at 5, 15, 30 and 60 GHz.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122382508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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