Pub Date : 2021-07-27DOI: 10.1109/NRSC52299.2021.9509785
M. A. El-Hassan, K. Hussein, K. Awadalla
A dual frequency-band (L and S) dual linearly-polarized microstrip patch antenna is proposed for synthetic aperture radar (SAR) system and communications applications. The proposed square patch antenna is printed on a roger TMM4 substrate. The proposed antenna has four L-shaped slots cut at the patch corners and four axial slots cut at the middle of each edge and perpendicular to it. The antenna has two ports; applying the feeding at one of them gives one of two orthogonal polarizations. The antenna is relatively compact, with an input impedance of 50Ω at each port. The antenna has been designed to work at 1.25 GHz and 3.3 GHz. The high isolation between the two feeding ports is −35 dB at 1.25GHz and −30 dB at 3.2GHz. The radiation patterns for the two polarizations are almost the same. The maximum gain of the antenna is about 4 dBi and 9 dBi at 1.25GHz and 3.3GHz, respectively. The CST commercial package has been used to analyze such antenna, and the HFSS package is used for confirmation of the produced results. The simulation results have proved the practicability of this antenna for dual polarized applications.
{"title":"Compact Dual-Band Dual-Polarized Microstrip Patch Antenna for Synthetic Aperture Radar","authors":"M. A. El-Hassan, K. Hussein, K. Awadalla","doi":"10.1109/NRSC52299.2021.9509785","DOIUrl":"https://doi.org/10.1109/NRSC52299.2021.9509785","url":null,"abstract":"A dual frequency-band (L and S) dual linearly-polarized microstrip patch antenna is proposed for synthetic aperture radar (SAR) system and communications applications. The proposed square patch antenna is printed on a roger TMM4 substrate. The proposed antenna has four L-shaped slots cut at the patch corners and four axial slots cut at the middle of each edge and perpendicular to it. The antenna has two ports; applying the feeding at one of them gives one of two orthogonal polarizations. The antenna is relatively compact, with an input impedance of 50Ω at each port. The antenna has been designed to work at 1.25 GHz and 3.3 GHz. The high isolation between the two feeding ports is −35 dB at 1.25GHz and −30 dB at 3.2GHz. The radiation patterns for the two polarizations are almost the same. The maximum gain of the antenna is about 4 dBi and 9 dBi at 1.25GHz and 3.3GHz, respectively. The CST commercial package has been used to analyze such antenna, and the HFSS package is used for confirmation of the produced results. The simulation results have proved the practicability of this antenna for dual polarized applications.","PeriodicalId":231431,"journal":{"name":"2021 38th National Radio Science Conference (NRSC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124239881","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 : 2021-07-27DOI: 10.1109/NRSC52299.2021.9509778
A. Maged, A. Madian, Amany I. Raafat, A. E. Ali
Flexible electrodes are developed using a novel conductive ink with various ratios of graphene nanoflakes decorated with copper nanospheres as a conductive filler. These electrodes represent potential candidates for energy storage devices and solid-state batteries. The electrodes are studied by AC measurements in the range of (0.1 Hz–500 kHz). Electrical impedance measurement data have been utilized for modeling the electrical properties of the conductive ink. The fitting is done using Z-Fit software and a randomized method followed by the Levenberg-Marquardt using the Cole-Cole model. The equivalent circuits are simulated by the Z-Sim software and values are compared with the theoretical values. The error between simulation value and theoretical value was found to be minimum. The aim of the work described in the present paper is to establish an equivalent electrical circuit for the conductive ink electrodes. The best and simplest circuit representation which gives the best fitting for the Cole-Cole and Nyquist plots consists of two resistors in parallel with a capacitor in series. The values of the electrical components are tabled, and the Cole-Cole plot is fitted to the measured data.
{"title":"Cole-Cole Modelling of Reduced Graphene Oxide Decorated CuO Nano-Spheres Based Waterproof Conductive Ink for Flexible Electrodes","authors":"A. Maged, A. Madian, Amany I. Raafat, A. E. Ali","doi":"10.1109/NRSC52299.2021.9509778","DOIUrl":"https://doi.org/10.1109/NRSC52299.2021.9509778","url":null,"abstract":"Flexible electrodes are developed using a novel conductive ink with various ratios of graphene nanoflakes decorated with copper nanospheres as a conductive filler. These electrodes represent potential candidates for energy storage devices and solid-state batteries. The electrodes are studied by AC measurements in the range of (0.1 Hz–500 kHz). Electrical impedance measurement data have been utilized for modeling the electrical properties of the conductive ink. The fitting is done using Z-Fit software and a randomized method followed by the Levenberg-Marquardt using the Cole-Cole model. The equivalent circuits are simulated by the Z-Sim software and values are compared with the theoretical values. The error between simulation value and theoretical value was found to be minimum. The aim of the work described in the present paper is to establish an equivalent electrical circuit for the conductive ink electrodes. The best and simplest circuit representation which gives the best fitting for the Cole-Cole and Nyquist plots consists of two resistors in parallel with a capacitor in series. The values of the electrical components are tabled, and the Cole-Cole plot is fitted to the measured data.","PeriodicalId":231431,"journal":{"name":"2021 38th National Radio Science Conference (NRSC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124381309","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 : 2021-07-27DOI: 10.1109/NRSC52299.2021.9509781
Esraa I. Hassan, R. Hamad, Mohamed I. Omar
This paper proposes a single microstrip antenna designed to operate at the 38 GHz fifth generation (5G) allocated band. This element is an altered circular microstrip patch antenna that is created and optimized to function at the desired band of frequency. The performance of the individual element is simulated and measured and its performance is evaluated at the perspective desired frequency. The individual optimized element impedance matching bandwidth reached at the 38 GHz is 0.6391 GHz utilizing a minimum return loss from −20.62249 dB. The achieved gain for the individual element is 7.5 dB at 37.9 GHz. The obtained radiation pattern is omni-directional at the desired frequency band. The measured and simulated results conform to a large degree and confirm the good performance with respect to gain, return loss, bandwidth as well as the radiation pattern. This makes the suggested the antenna suitable for 5G applications.
{"title":"A 38 GHz Modified Circular Microstrip Patch Antenna for 5G Mobile Systems","authors":"Esraa I. Hassan, R. Hamad, Mohamed I. Omar","doi":"10.1109/NRSC52299.2021.9509781","DOIUrl":"https://doi.org/10.1109/NRSC52299.2021.9509781","url":null,"abstract":"This paper proposes a single microstrip antenna designed to operate at the 38 GHz fifth generation (5G) allocated band. This element is an altered circular microstrip patch antenna that is created and optimized to function at the desired band of frequency. The performance of the individual element is simulated and measured and its performance is evaluated at the perspective desired frequency. The individual optimized element impedance matching bandwidth reached at the 38 GHz is 0.6391 GHz utilizing a minimum return loss from −20.62249 dB. The achieved gain for the individual element is 7.5 dB at 37.9 GHz. The obtained radiation pattern is omni-directional at the desired frequency band. The measured and simulated results conform to a large degree and confirm the good performance with respect to gain, return loss, bandwidth as well as the radiation pattern. This makes the suggested the antenna suitable for 5G applications.","PeriodicalId":231431,"journal":{"name":"2021 38th National Radio Science Conference (NRSC)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131261505","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 : 2021-07-27DOI: 10.1109/NRSC52299.2021.9509809
A. Y. Hassan, Mahmoud O. El Beshry, Khaled T. Harb, H. El Hennawy
This paper aims to propose a multiuser OFDM system with non-coherent differential quadrature chaos-shift-keying (OFDM-DQCSK) modulation. The proposed system is based on direct sequence spread spectrum where chaotic codes replace conventional spreading sequences. Orthogonal sets of chaotic spreading codes can be generated. The proposed system uses duplicated reference subcarriers that are private and non-shared. At the receiver, these reference subcarriers are used for the differential non-coherent de-spreading. Neither complex channel estimators nor carrier synchronization is required for demodulation. The chaotic reference signals are averaged at the receiver so that the additive white gaussian noise (AWGN) on the reference signal is averaged to a negligible value. A simulation of the bit error rate performance is performed in the presence of AWGN, multipath Rayleigh flat-fading channels and multiple access interference (MAI). In conclusion, the proposed non-coherent system achieves a remarkable improvement due to the usage of the Reference Averaging Technique.
{"title":"Design and Performance Evaluation of a Multiuser OFDM System Based on Differential Quadrature Chaos-Shift-Keying Spread Spectrum","authors":"A. Y. Hassan, Mahmoud O. El Beshry, Khaled T. Harb, H. El Hennawy","doi":"10.1109/NRSC52299.2021.9509809","DOIUrl":"https://doi.org/10.1109/NRSC52299.2021.9509809","url":null,"abstract":"This paper aims to propose a multiuser OFDM system with non-coherent differential quadrature chaos-shift-keying (OFDM-DQCSK) modulation. The proposed system is based on direct sequence spread spectrum where chaotic codes replace conventional spreading sequences. Orthogonal sets of chaotic spreading codes can be generated. The proposed system uses duplicated reference subcarriers that are private and non-shared. At the receiver, these reference subcarriers are used for the differential non-coherent de-spreading. Neither complex channel estimators nor carrier synchronization is required for demodulation. The chaotic reference signals are averaged at the receiver so that the additive white gaussian noise (AWGN) on the reference signal is averaged to a negligible value. A simulation of the bit error rate performance is performed in the presence of AWGN, multipath Rayleigh flat-fading channels and multiple access interference (MAI). In conclusion, the proposed non-coherent system achieves a remarkable improvement due to the usage of the Reference Averaging Technique.","PeriodicalId":231431,"journal":{"name":"2021 38th National Radio Science Conference (NRSC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128083676","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 : 2021-07-27DOI: 10.1109/NRSC52299.2021.9509779
B. M. Yousef, Zeeshan Yousuf, A. M. Ameen, Ayman Elboushi
In this paper, a high-gain annular ring with meander slots antenna array is presented. The proposed design is realized on two different substrate materials separated by a foam layer of 7.5 mm to enhance the operating bandwidth. The antenna is designed to operated as UHF-RFID reading antenna over center frequency of 915 MHz with operating bandwidth of 49.25 MHz (around 5.38%). The overall antenna optimized dimensions are 240×240×11.56 mm3. An overall total realized gain of 12.5 dBi is achieved at the intended center frequency. The proposed antenna exhibits stable radiation capabilities over the operating band. Good agreement is obtained between both CSTMWS, and HFSS simulators.
{"title":"High-Gain Annular Ring with Meander Slots Antenna Array for RFID Applications","authors":"B. M. Yousef, Zeeshan Yousuf, A. M. Ameen, Ayman Elboushi","doi":"10.1109/NRSC52299.2021.9509779","DOIUrl":"https://doi.org/10.1109/NRSC52299.2021.9509779","url":null,"abstract":"In this paper, a high-gain annular ring with meander slots antenna array is presented. The proposed design is realized on two different substrate materials separated by a foam layer of 7.5 mm to enhance the operating bandwidth. The antenna is designed to operated as UHF-RFID reading antenna over center frequency of 915 MHz with operating bandwidth of 49.25 MHz (around 5.38%). The overall antenna optimized dimensions are 240×240×11.56 mm3. An overall total realized gain of 12.5 dBi is achieved at the intended center frequency. The proposed antenna exhibits stable radiation capabilities over the operating band. Good agreement is obtained between both CSTMWS, and HFSS simulators.","PeriodicalId":231431,"journal":{"name":"2021 38th National Radio Science Conference (NRSC)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115598900","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 : 2021-07-27DOI: 10.1109/NRSC52299.2021.9509832
Mohammad T. Haweel, O. Zahran, F. A. Abd El-Samie
An efficient adaptive classifier for fetal electronic monitoring based on a modified structure of neural networks is presented. It employs polynomial series as a functional expansion. Training of the Polynomial Neural Network (PNN) classifier is performed using a NewtonLeast Mean Square (NLMS) adaptive algorithm, which requires few iterations and epochs. The convergence is achieved using the PNN classifier in a very short training time. The performance of the proposed classifier has shown a very high overall classification accuracy of 99.74% in comparison with those of the other excising machine learning classifiers. A performance comparison between the proposed PNN classifier and other Functional Link Artificial Neural Network (FLANN) classifiers such as Legendre Neural Network (LNN) and Volterra Neural Network (VNN) based classifiers in electronic fetal monitoring is provided. The simulation results reveal that the PNN classifier outperforms both the LNN and VNN classifiers in terms of mean square error, overall classification accuracy, computational time and computational complexity.
{"title":"Polynomial FLANN Classifier for Fetal Cardiotocography Monitoring","authors":"Mohammad T. Haweel, O. Zahran, F. A. Abd El-Samie","doi":"10.1109/NRSC52299.2021.9509832","DOIUrl":"https://doi.org/10.1109/NRSC52299.2021.9509832","url":null,"abstract":"An efficient adaptive classifier for fetal electronic monitoring based on a modified structure of neural networks is presented. It employs polynomial series as a functional expansion. Training of the Polynomial Neural Network (PNN) classifier is performed using a NewtonLeast Mean Square (NLMS) adaptive algorithm, which requires few iterations and epochs. The convergence is achieved using the PNN classifier in a very short training time. The performance of the proposed classifier has shown a very high overall classification accuracy of 99.74% in comparison with those of the other excising machine learning classifiers. A performance comparison between the proposed PNN classifier and other Functional Link Artificial Neural Network (FLANN) classifiers such as Legendre Neural Network (LNN) and Volterra Neural Network (VNN) based classifiers in electronic fetal monitoring is provided. The simulation results reveal that the PNN classifier outperforms both the LNN and VNN classifiers in terms of mean square error, overall classification accuracy, computational time and computational complexity.","PeriodicalId":231431,"journal":{"name":"2021 38th National Radio Science Conference (NRSC)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117286544","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 : 2021-07-27DOI: 10.1109/NRSC52299.2021.9509833
H. Malhat, E. A. El-Refaay, S. Zainud-Deen
This paper proposes a compact multi-bits chipless-RFID tag using fully printed resonators with dual performance of tagging and sensing temperature. Each bit is modelled as curl resonator coupled to microstrip line and is printed on metal-backed Rogers RO4003 substrate. A −10 dB attenuation level is obtained with narrow bandwidth and power reflection of −3.2 dB. The effect of the tag dimensions on the transmission coefficient response is introduced. The resonance frequency of each bit is controlled via controlling the curl arm’s length. The multi-bits RFID tag is modelled using multi-curl resonators arranged next to microstrip line with different arm lengths. A multi-bits chipless-RFID tags with 3-bits, 6-bits and 12-bits are designed in the 3–7 GHz frequency band. The dimensions of 6-bits code are 60×17 mm2 and for 12-bits code are 29.75×34 mm2. A temperature sensing capability is achieved via integrated Stanyl polyamide material with the curl resonator. The first bit is used for temperature sensing while the other bits are used for data encoding. The proposed chipless-RFID tags are simulated using finite element method (FEM) and finite integral technique (FIT).
{"title":"Compact Multi-bits Chipless-RFID Curl Resonator Tag with Temperature Sensing Capability","authors":"H. Malhat, E. A. El-Refaay, S. Zainud-Deen","doi":"10.1109/NRSC52299.2021.9509833","DOIUrl":"https://doi.org/10.1109/NRSC52299.2021.9509833","url":null,"abstract":"This paper proposes a compact multi-bits chipless-RFID tag using fully printed resonators with dual performance of tagging and sensing temperature. Each bit is modelled as curl resonator coupled to microstrip line and is printed on metal-backed Rogers RO4003 substrate. A −10 dB attenuation level is obtained with narrow bandwidth and power reflection of −3.2 dB. The effect of the tag dimensions on the transmission coefficient response is introduced. The resonance frequency of each bit is controlled via controlling the curl arm’s length. The multi-bits RFID tag is modelled using multi-curl resonators arranged next to microstrip line with different arm lengths. A multi-bits chipless-RFID tags with 3-bits, 6-bits and 12-bits are designed in the 3–7 GHz frequency band. The dimensions of 6-bits code are 60×17 mm2 and for 12-bits code are 29.75×34 mm2. A temperature sensing capability is achieved via integrated Stanyl polyamide material with the curl resonator. The first bit is used for temperature sensing while the other bits are used for data encoding. The proposed chipless-RFID tags are simulated using finite element method (FEM) and finite integral technique (FIT).","PeriodicalId":231431,"journal":{"name":"2021 38th National Radio Science Conference (NRSC)","volume":"127 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124557514","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 : 2021-07-27DOI: 10.1109/NRSC52299.2021.9509816
Hazem H. Hammam, H. Omran, S. Ibrahim
Having a high-power supply rejection (PSR) over a wide range of frequencies is a very important specification for most of low-dropout voltage regulators (LDOs). A low-power LDO with 2 methods of high-frequency PSR and loop stability compensation techniques is presented in this paper. The proposed LDO achieves a high PSR over a wide frequency range with low power and small area consumption. The LDO is implemented in 65 nm CMOS technology and achieves a PSR better than 77 dB up to 30 MHz for output load currents up to 25 mA and a 4 μF output load capacitor. The design is suitable for capacitor loaded (Capped) LDOs with a wide output load current range up to 100 mA and output load capacitor range from 1 μF to 12 μF. The proposed LDO consumes a no-load quiescent current of 5 μA and an area of 400 μm × 200 μm.
{"title":"Ultra-Low-Power Low Drop-Out (LDO) Voltage Regulator With Improved Power Supply Rejection","authors":"Hazem H. Hammam, H. Omran, S. Ibrahim","doi":"10.1109/NRSC52299.2021.9509816","DOIUrl":"https://doi.org/10.1109/NRSC52299.2021.9509816","url":null,"abstract":"Having a high-power supply rejection (PSR) over a wide range of frequencies is a very important specification for most of low-dropout voltage regulators (LDOs). A low-power LDO with 2 methods of high-frequency PSR and loop stability compensation techniques is presented in this paper. The proposed LDO achieves a high PSR over a wide frequency range with low power and small area consumption. The LDO is implemented in 65 nm CMOS technology and achieves a PSR better than 77 dB up to 30 MHz for output load currents up to 25 mA and a 4 μF output load capacitor. The design is suitable for capacitor loaded (Capped) LDOs with a wide output load current range up to 100 mA and output load capacitor range from 1 μF to 12 μF. The proposed LDO consumes a no-load quiescent current of 5 μA and an area of 400 μm × 200 μm.","PeriodicalId":231431,"journal":{"name":"2021 38th National Radio Science Conference (NRSC)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133341339","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 : 2021-07-27DOI: 10.1109/NRSC52299.2021.9509786
Hebatullah M. Sakr, A. Diab, Ramy Elamrawy, M. Elsabrouty
Validating the performance of wireless networks using hardware testbeds is an essential task to see networks’ performance in real environments. In this paper, we present an experimental evaluation of the performance of different interference alignment techniques for both homogeneous and heterogeneous networks (HetNets) conducted on a wireless testbed comprised of a total of 20 multi-input multi-output (MIMO) software-defined radio (SDR) devices. Four interference alignment (IA) techniques are considered, namely, rank constrained rank minimization (RCRM), weighted rank constrained rank minimization (WRCRM), leakage minimization and maximum signal-to-interference-plus-noise ratio (SINR). The four IA algorithms are first implemented on a downlink three-user homogeneous network using a cluster of 6 USRPs and the LabVIEW programming environment. Then, the comparison is conducted for a three-tier downlink heterogeneous network with a macro base station (BS) of 6 antennas, a small BS with 4 antennas, and a cognitive-radio BS with 2 antennas, giving a mutually interfering broadcast channel (MIBC). Our paper shows the implementation procedures and discusses the systems’ configuration from both hardware and software aspects. The experimental real-time results compare the performance of the different IA schemes showing the impact of practical constraints on the evaluation results.
{"title":"Experimental Validation of Interference Alignment Techniques for Homogeneous and Three-Tier HetNets Using USRP-Testbed","authors":"Hebatullah M. Sakr, A. Diab, Ramy Elamrawy, M. Elsabrouty","doi":"10.1109/NRSC52299.2021.9509786","DOIUrl":"https://doi.org/10.1109/NRSC52299.2021.9509786","url":null,"abstract":"Validating the performance of wireless networks using hardware testbeds is an essential task to see networks’ performance in real environments. In this paper, we present an experimental evaluation of the performance of different interference alignment techniques for both homogeneous and heterogeneous networks (HetNets) conducted on a wireless testbed comprised of a total of 20 multi-input multi-output (MIMO) software-defined radio (SDR) devices. Four interference alignment (IA) techniques are considered, namely, rank constrained rank minimization (RCRM), weighted rank constrained rank minimization (WRCRM), leakage minimization and maximum signal-to-interference-plus-noise ratio (SINR). The four IA algorithms are first implemented on a downlink three-user homogeneous network using a cluster of 6 USRPs and the LabVIEW programming environment. Then, the comparison is conducted for a three-tier downlink heterogeneous network with a macro base station (BS) of 6 antennas, a small BS with 4 antennas, and a cognitive-radio BS with 2 antennas, giving a mutually interfering broadcast channel (MIBC). Our paper shows the implementation procedures and discusses the systems’ configuration from both hardware and software aspects. The experimental real-time results compare the performance of the different IA schemes showing the impact of practical constraints on the evaluation results.","PeriodicalId":231431,"journal":{"name":"2021 38th National Radio Science Conference (NRSC)","volume":"136 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133454456","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 : 2021-07-27DOI: 10.1109/NRSC52299.2021.9509787
Mohamed Kilany, Zhou Ding, George A. Adib, Y. Sabry, Chengxiang Liu, D. Khalil
Optical fibers have recently become an essential part of any communication system. Erbium-doped photonic crystal fibers (EDPCF) have special optical properties that can be used in interesting applications like interferometric sensors and supercontinuum sources. In this work, we report active optical fiber cavities that enhance the linewidth of passive fiber filters. In the proposed configuration, an Erbium-doped photonic crystal fiber (EDPCF) is used as a gain medium with a passive fiber filter. The EDPCF gain reaches 30 dB around the center wavelength of 1560 nm. The 3-dB linewidth of the filter is originally 7.7 nm and reaches 4.2 nm after enhancement. This configuration is compared with another one where the gain medium is a semiconductor optical amplifier (SOA). The 3-dB linewidth enhancement is 1.83× in the case of EDPCF, while it is 2× in the case of SOA.
{"title":"Optical Fiber Filters Linewidth Enhancement Based on Erbium-doped Photonic Crystal Fiber Cavities","authors":"Mohamed Kilany, Zhou Ding, George A. Adib, Y. Sabry, Chengxiang Liu, D. Khalil","doi":"10.1109/NRSC52299.2021.9509787","DOIUrl":"https://doi.org/10.1109/NRSC52299.2021.9509787","url":null,"abstract":"Optical fibers have recently become an essential part of any communication system. Erbium-doped photonic crystal fibers (EDPCF) have special optical properties that can be used in interesting applications like interferometric sensors and supercontinuum sources. In this work, we report active optical fiber cavities that enhance the linewidth of passive fiber filters. In the proposed configuration, an Erbium-doped photonic crystal fiber (EDPCF) is used as a gain medium with a passive fiber filter. The EDPCF gain reaches 30 dB around the center wavelength of 1560 nm. The 3-dB linewidth of the filter is originally 7.7 nm and reaches 4.2 nm after enhancement. This configuration is compared with another one where the gain medium is a semiconductor optical amplifier (SOA). The 3-dB linewidth enhancement is 1.83× in the case of EDPCF, while it is 2× in the case of SOA.","PeriodicalId":231431,"journal":{"name":"2021 38th National Radio Science Conference (NRSC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130986828","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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