Pub Date : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235120
M. M. Mohamed, H. El-Badawy, Reem Abdelhadi, A. Ammar
Heterogeneous network is considered a powerful key to increase network capacity and provide high quality of service (QoS) for network users. However, in a heterogeneous network composed of femtocells and a macrocell, Macro users in poor signal places prefer to access to the nearest femtocell. Thus, these accessing will have a bad effect on femto users. Therefore, in this paper, first we propose an adaptive femtocell access system model to control the resource allocation between femto users (FUs) and macro users (MUs). Using the proposed adaptive system model, the most appropriate femtocell access mode will be determined. Second, a borrowing technique is proposed to be an arm of safety for femtocells that suffer from high traffic density. Simulation results show the adaptation of femtocell access modes with a varying network density to guarantee high QoS for FUs and help suffered MUs to get services without affecting the demands of FUs. Also; Simulation results show that the overall network performance can be improved using the proposed borrowing technique model as the number of blocking MUs can be decreased from 93 MU to zero MU. Also results show that, the proposed model will outperform the system performance by 52% with respect to the closed system model.
{"title":"Adaptive Femtocell Accessing Control in A 5g Heterogeneous Network","authors":"M. M. Mohamed, H. El-Badawy, Reem Abdelhadi, A. Ammar","doi":"10.1109/NRSC49500.2020.9235120","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235120","url":null,"abstract":"Heterogeneous network is considered a powerful key to increase network capacity and provide high quality of service (QoS) for network users. However, in a heterogeneous network composed of femtocells and a macrocell, Macro users in poor signal places prefer to access to the nearest femtocell. Thus, these accessing will have a bad effect on femto users. Therefore, in this paper, first we propose an adaptive femtocell access system model to control the resource allocation between femto users (FUs) and macro users (MUs). Using the proposed adaptive system model, the most appropriate femtocell access mode will be determined. Second, a borrowing technique is proposed to be an arm of safety for femtocells that suffer from high traffic density. Simulation results show the adaptation of femtocell access modes with a varying network density to guarantee high QoS for FUs and help suffered MUs to get services without affecting the demands of FUs. Also; Simulation results show that the overall network performance can be improved using the proposed borrowing technique model as the number of blocking MUs can be decreased from 93 MU to zero MU. Also results show that, the proposed model will outperform the system performance by 52% with respect to the closed system model.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"17 1","pages":"85-94"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73095219","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 : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235111
Nabil R. Soliman, Karim D. Khalil, Ahmed M. Abd El Khalik, H. Omran
Bandgap voltage references are present in virtually every analog/mixed-signal system. However, their design still remains a time-consuming procedure that requires extensive designer expertise and validation. In this paper, an automated bandgap synthesis procedure is used to generate a dataset that maps the specifications of the synthesized bandgap reference circuit to their corresponding designer's degrees of freedom. This dataset is then used to train a neural network to predict the choice of the degrees of freedom in order to meet arbitrary circuit specifications specified by the user including variations due to design corners and random mismatch. The automated bandgap synthesis procedure uses precomputed look-up tables rather than invoking a circuit simulator in the loop, which enables generating a large dataset of training examples in short time. The choice of the degrees of freedom predicted by the neural network is then re-fed to the bandgap synthesis procedure to verify the accuracy of the prediction and obtain the complete solution of the synthesized circuit. The results demonstrate that the trained neural network is capable of making successful predictions of good accuracy in a wide multi-dimensional design space.
{"title":"Application of Artificial Neural Networks to the Automation of Bandgap Reference Synthesis","authors":"Nabil R. Soliman, Karim D. Khalil, Ahmed M. Abd El Khalik, H. Omran","doi":"10.1109/NRSC49500.2020.9235111","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235111","url":null,"abstract":"Bandgap voltage references are present in virtually every analog/mixed-signal system. However, their design still remains a time-consuming procedure that requires extensive designer expertise and validation. In this paper, an automated bandgap synthesis procedure is used to generate a dataset that maps the specifications of the synthesized bandgap reference circuit to their corresponding designer's degrees of freedom. This dataset is then used to train a neural network to predict the choice of the degrees of freedom in order to meet arbitrary circuit specifications specified by the user including variations due to design corners and random mismatch. The automated bandgap synthesis procedure uses precomputed look-up tables rather than invoking a circuit simulator in the loop, which enables generating a large dataset of training examples in short time. The choice of the degrees of freedom predicted by the neural network is then re-fed to the bandgap synthesis procedure to verify the accuracy of the prediction and obtain the complete solution of the synthesized circuit. The results demonstrate that the trained neural network is capable of making successful predictions of good accuracy in a wide multi-dimensional design space.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"5 1","pages":"106-116"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89105782","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 : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235108
S. El-Khamy, Dalia I. Mohamed
Underwater acoustic channels (UWAC) are characterized by time-varying frequency selective fading. OFDM technique is suitable for UWAC due to its robustness to channel’s frequency selectivity. As acoustic transmission is supported at low frequencies, the channels suffer from low capacity. Using sparse Non-OFDM (S-NOFDM), spectral efficiency of OFDM is improved to overcome capacity limitations. The subcarriers of S-NOFDM are generated from a subset of OFDM orthogonal sub-channels and hence, it requires fewer spectral resources. Then, time shift is used to generate a number of non-orthogonal subcarriers to substitute for the reduction of OFDM sub-channels used in transmission. Channel-Matched S-NOFDM approach is investigated, where the set of selected sub-channels corresponds to maximum transmission through the channel. The results indicate that the proposed scheme has better performance than S-NOFDM and it approaches the performance of OFDM while using less spectral resources.
{"title":"Channel Matched Sparse Non-Orthogonal frequency division multiplexing (CM-SNOFDM) Operating in Underwater Acoustic Channels","authors":"S. El-Khamy, Dalia I. Mohamed","doi":"10.1109/NRSC49500.2020.9235108","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235108","url":null,"abstract":"Underwater acoustic channels (UWAC) are characterized by time-varying frequency selective fading. OFDM technique is suitable for UWAC due to its robustness to channel’s frequency selectivity. As acoustic transmission is supported at low frequencies, the channels suffer from low capacity. Using sparse Non-OFDM (S-NOFDM), spectral efficiency of OFDM is improved to overcome capacity limitations. The subcarriers of S-NOFDM are generated from a subset of OFDM orthogonal sub-channels and hence, it requires fewer spectral resources. Then, time shift is used to generate a number of non-orthogonal subcarriers to substitute for the reduction of OFDM sub-channels used in transmission. Channel-Matched S-NOFDM approach is investigated, where the set of selected sub-channels corresponds to maximum transmission through the channel. The results indicate that the proposed scheme has better performance than S-NOFDM and it approaches the performance of OFDM while using less spectral resources.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"14 1","pages":"164-172"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74987494","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 : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235102
E. A. El-Refaay, S. Zainud-Deen, H. Malhat
This paper introduces a planar circular split ring resonator (CSRR) coupled to microstrip transmission line (TL) for the rotation angle sensor. For each rotation angle, the CSRR acts as a stop-band filter and absorbs the signal flow through the TL. The CSRR sensor introduces a resonance at 4.13 GHz with a -10 dB bandwidth of 370 MHz. High attenuation of 40 dB is achieved with reflection of 0.17 dB. A parametric study on the effect of each of CSRR design parameters on the performance of the sensor is introduced. Mathematical modelling of the variations of resonant frequency with different design parameters are derived and verified. The performance of the proposed sensor for rotation angle detection is investigated. A five-elements equivalent circuit model is prepared to represent the inductive and capacitive coupling of the CSRR and TL. The particle swarm optimization (PSO) is employed to find the optimal values of the equivalent circuit elements at different rotation angles.
{"title":"Angular Displacement Sensor Based on Planar Circular Split Ring Resonator","authors":"E. A. El-Refaay, S. Zainud-Deen, H. Malhat","doi":"10.1109/NRSC49500.2020.9235102","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235102","url":null,"abstract":"This paper introduces a planar circular split ring resonator (CSRR) coupled to microstrip transmission line (TL) for the rotation angle sensor. For each rotation angle, the CSRR acts as a stop-band filter and absorbs the signal flow through the TL. The CSRR sensor introduces a resonance at 4.13 GHz with a -10 dB bandwidth of 370 MHz. High attenuation of 40 dB is achieved with reflection of 0.17 dB. A parametric study on the effect of each of CSRR design parameters on the performance of the sensor is introduced. Mathematical modelling of the variations of resonant frequency with different design parameters are derived and verified. The performance of the proposed sensor for rotation angle detection is investigated. A five-elements equivalent circuit model is prepared to represent the inductive and capacitive coupling of the CSRR and TL. The particle swarm optimization (PSO) is employed to find the optimal values of the equivalent circuit elements at different rotation angles.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"79 1","pages":"9-15"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82402012","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 : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235109
M. Ismail, A. R. Eldamak, H. Ghali
This paper introduces printed Meander dipole antenna with dual bands operating at 73 MHz and 145.75 MHz for low frequency and Ground Penetrating Radar (GPR) applications. The antenna is implemented on FR4 substrate with an overall size of 61.3 X6.45 cm2 (0.15λo x 0.015λo). A 70% reduction in length is realized with the proposed antenna design compared to a regular dipole operating at the lower band. The reflection coefficient for the measured antenna is -15 dB and -18.5 dB at 73 MHz and 145.75 MHz with bandwidth of 2 MHz and 6.6 MHz, respectively. The antenna exhibits omnidirectional radiation characteristics at both bands with radiation efficiency up to 87%. The proposed structure is fabricated, measured and compared to simulated results. Measurements are in good agreement with simulation results. Moreover, measurements and simulations for antenna in proximity to soil as well as with buried objects are also presented.
{"title":"Meander Dipole Antenna for Low Frequency Applications","authors":"M. Ismail, A. R. Eldamak, H. Ghali","doi":"10.1109/NRSC49500.2020.9235109","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235109","url":null,"abstract":"This paper introduces printed Meander dipole antenna with dual bands operating at 73 MHz and 145.75 MHz for low frequency and Ground Penetrating Radar (GPR) applications. The antenna is implemented on FR4 substrate with an overall size of 61.3 X6.45 cm2 (0.15λo x 0.015λo). A 70% reduction in length is realized with the proposed antenna design compared to a regular dipole operating at the lower band. The reflection coefficient for the measured antenna is -15 dB and -18.5 dB at 73 MHz and 145.75 MHz with bandwidth of 2 MHz and 6.6 MHz, respectively. The antenna exhibits omnidirectional radiation characteristics at both bands with radiation efficiency up to 87%. The proposed structure is fabricated, measured and compared to simulated results. Measurements are in good agreement with simulation results. Moreover, measurements and simulations for antenna in proximity to soil as well as with buried objects are also presented.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"13 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82971609","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 : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235117
Amany S. Saber, M. Shaat, A. El-Sayed, Hanaa Torkey, M. Shouman
In recent years, the rapid progress of digital technology to safety-critical systems such as the digital reactor protection system (RPS) is increased. The proposed method aims to make a quantitative evaluation model for the reliability analysis of digital RPS with 2-out-of-4 architecture using the state transition diagram to be sure that Nuclear power plants (NPP) will be in a state to perform a required tasks under given conditions over a time interval. The detection time of the failure, the repair time of failed components and Mean Time to Repair (MTTR) are used in this study. The Probability of Failure on Demand (PFD) of the digital RPS caused by independent hardware failure is calculated and the effect on the system is analyzed. The results show that the proposed method is more effectiveness and appropriate to model the digital RPS and to analyze reliability than conventional Fault Tree Analysis (FTA) method.
{"title":"Reliability Analysis Model of the Digital Reactor Protection System","authors":"Amany S. Saber, M. Shaat, A. El-Sayed, Hanaa Torkey, M. Shouman","doi":"10.1109/NRSC49500.2020.9235117","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235117","url":null,"abstract":"In recent years, the rapid progress of digital technology to safety-critical systems such as the digital reactor protection system (RPS) is increased. The proposed method aims to make a quantitative evaluation model for the reliability analysis of digital RPS with 2-out-of-4 architecture using the state transition diagram to be sure that Nuclear power plants (NPP) will be in a state to perform a required tasks under given conditions over a time interval. The detection time of the failure, the repair time of failed components and Mean Time to Repair (MTTR) are used in this study. The Probability of Failure on Demand (PFD) of the digital RPS caused by independent hardware failure is calculated and the effect on the system is analyzed. The results show that the proposed method is more effectiveness and appropriate to model the digital RPS and to analyze reliability than conventional Fault Tree Analysis (FTA) method.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"29 1","pages":"230-239"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89547451","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 : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235100
Y. Badran, G. Salama, T. Mahmoud, Aiman M. Mousa, Adel E. Moussa
Single image super resolution restoration is a process for solving the ill-posed problem of achieving a high resolution image from one low resolution image. This process is considered an active point of research due to the increased demands for high resolution imagery in many applications. This paper presents a proposed methodology for single image super resolution based on replacing the traditional discrete cosine transform basis. These bases are replaced by learned filters that can transfer the low resolution image from the spatial domain to high resolution coefficients in the discrete cosine domain. Accordingly, these estimated filters can then be applied to produce a high resolution image in the spatial domain through the standard inverse discrete cosine transform process. To learn these transformation filters two modifications in the decision tree algorithm are introduced to adapt the tree performance for the super resolution task. This is performed such that the node splitting decision depends on external features that minimize the regression errors. Experimental results demonstrate that the performance of the proposed algorithm is superior to that of the traditional interpolation single image super resolution method.
{"title":"Single Image Super Resolution Using Discrete Cosine Transform Driven Regression Tree","authors":"Y. Badran, G. Salama, T. Mahmoud, Aiman M. Mousa, Adel E. Moussa","doi":"10.1109/NRSC49500.2020.9235100","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235100","url":null,"abstract":"Single image super resolution restoration is a process for solving the ill-posed problem of achieving a high resolution image from one low resolution image. This process is considered an active point of research due to the increased demands for high resolution imagery in many applications. This paper presents a proposed methodology for single image super resolution based on replacing the traditional discrete cosine transform basis. These bases are replaced by learned filters that can transfer the low resolution image from the spatial domain to high resolution coefficients in the discrete cosine domain. Accordingly, these estimated filters can then be applied to produce a high resolution image in the spatial domain through the standard inverse discrete cosine transform process. To learn these transformation filters two modifications in the decision tree algorithm are introduced to adapt the tree performance for the super resolution task. This is performed such that the node splitting decision depends on external features that minimize the regression errors. Experimental results demonstrate that the performance of the proposed algorithm is superior to that of the traditional interpolation single image super resolution method.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"55 7","pages":"128-136"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91466050","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 : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235094
A. M. Mabrouk, S. Zainud-Deen, H. Malhat, A. Ibrahim, H. Hamed
In this paper, reconfigurable polarization converter from linear polarization to circular polarization is designed based on graphene artificial magnetic conductor surface. The reconfigurable conductivity of the graphene material allows the change of electromagnetic wave polarization left-hand and right-hand circular polarization (CP) through electrical DC biasing. The gain enhancement of V-shaped dipole antenna is achieved by backing it with AMC array. The antenna gain is increased up to 4.7 dBi with AMC ground plane. Different AMC ground plane sizes and their effect on polarization conversion are investigated. The polarization conversion bandwidth is 19.44% for 7x7 AMC array. Full-wave analysis is used to model the array structure.
{"title":"Graphene-Based AMC Polarization Converter for Antenna Applications at Microwave Frequency Band","authors":"A. M. Mabrouk, S. Zainud-Deen, H. Malhat, A. Ibrahim, H. Hamed","doi":"10.1109/NRSC49500.2020.9235094","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235094","url":null,"abstract":"In this paper, reconfigurable polarization converter from linear polarization to circular polarization is designed based on graphene artificial magnetic conductor surface. The reconfigurable conductivity of the graphene material allows the change of electromagnetic wave polarization left-hand and right-hand circular polarization (CP) through electrical DC biasing. The gain enhancement of V-shaped dipole antenna is achieved by backing it with AMC array. The antenna gain is increased up to 4.7 dBi with AMC ground plane. Different AMC ground plane sizes and their effect on polarization conversion are investigated. The polarization conversion bandwidth is 19.44% for 7x7 AMC array. Full-wave analysis is used to model the array structure.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"18 1","pages":"16-23"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81046658","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 : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235101
Said E. El Khamy, N. Korany, H. Hassan
A new design of MIMO-OFDM channel estimation using complementary codes is proposed in this paper. In the proposed algorithm a 2x2 space time code MIMO-OFDM system is considered. Instead of using single sided channel estimation techniques as in previous investigation [1], a two-sided approach is considered in. The suggested code on frequency-antenna distribution covers all the OFDM subcarriers. This is an advantage of our algorithm as previous investigations use only half of the subcarriers of the channel estimation. The considered channel model is a multi-tap fading channel model with doppler shift. The simulation results of the proposed algorithm are done assuming multi taps Rayleigh fading channel. Good results are obtained compared to other previous approaches of using complementary code in the estimation of MIMO-OFDM channels at low SNR and channel taps equal one and two.
{"title":"Channel Estimation Techniques for Wideband MIMO-OFDM Communication Systems Using Complementary Codes Two-Sided Sequences","authors":"Said E. El Khamy, N. Korany, H. Hassan","doi":"10.1109/NRSC49500.2020.9235101","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235101","url":null,"abstract":"A new design of MIMO-OFDM channel estimation using complementary codes is proposed in this paper. In the proposed algorithm a 2x2 space time code MIMO-OFDM system is considered. Instead of using single sided channel estimation techniques as in previous investigation [1], a two-sided approach is considered in. The suggested code on frequency-antenna distribution covers all the OFDM subcarriers. This is an advantage of our algorithm as previous investigations use only half of the subcarriers of the channel estimation. The considered channel model is a multi-tap fading channel model with doppler shift. The simulation results of the proposed algorithm are done assuming multi taps Rayleigh fading channel. Good results are obtained compared to other previous approaches of using complementary code in the estimation of MIMO-OFDM channels at low SNR and channel taps equal one and two.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"91 1","pages":"74-84"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82294190","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 : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235103
M. Abdallah, Y. Sabry, A. Mahfouz, F. Marty, T. Bourouina, H. Omran
In this paper, we report FDTD simulations and experimental results of novel silicon-based optical microcavity comprising of two slotted micromirrors. While the normal range for silicon microcavities is limited by its absorption below 1.1 μm, we demonstrate a silicon cavity that is capable of operation from the visible spectrum till the telecom C-band. Deep reactive ion etching (DRIE) is used to fabricate the deeply etched microcavity mirrors. The structure is metallized with gold to enhance mirrors’ reflectivity. The slotted mirror and the cavity structure are simulated using finite difference time domain (FDTD), and the results are reported showing a quality factor of 2796 for visible TM excitation and a quality factor of 2346 for NIR TM excitation. The experimental results report the characteristics of the resonator and verify its operation in the NIR and visible ranges. The measured quality factor (Q) is 2067 around the 565 nm peak and 1922 around the 1550 nm peak. Such a microcavity would present a major step towards realizing visible laser on silicon for micro optofluidic applications.
{"title":"Optical Cavity with Large Operational Bandwidth using Silicon-Based Slotted Micromirrors","authors":"M. Abdallah, Y. Sabry, A. Mahfouz, F. Marty, T. Bourouina, H. Omran","doi":"10.1109/NRSC49500.2020.9235103","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235103","url":null,"abstract":"In this paper, we report FDTD simulations and experimental results of novel silicon-based optical microcavity comprising of two slotted micromirrors. While the normal range for silicon microcavities is limited by its absorption below 1.1 μm, we demonstrate a silicon cavity that is capable of operation from the visible spectrum till the telecom C-band. Deep reactive ion etching (DRIE) is used to fabricate the deeply etched microcavity mirrors. The structure is metallized with gold to enhance mirrors’ reflectivity. The slotted mirror and the cavity structure are simulated using finite difference time domain (FDTD), and the results are reported showing a quality factor of 2796 for visible TM excitation and a quality factor of 2346 for NIR TM excitation. The experimental results report the characteristics of the resonator and verify its operation in the NIR and visible ranges. The measured quality factor (Q) is 2067 around the 565 nm peak and 1922 around the 1550 nm peak. Such a microcavity would present a major step towards realizing visible laser on silicon for micro optofluidic applications.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"24 1","pages":"222-229"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89410538","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：