Pub Date : 2019-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713053
J. Diao, M. Hedayati, Y. E. Wang
Combing distributed small wireless systems on mobile platforms such as swarm airborne mini-drones has been explored recently. Localization and synchronization of the mobile drones are the main challenges limiting its practical applications. In this paper, we proposed a new approach to circumvent this limits by considering the drones as relay nodes, where the received signals are modulated to different frequencies and then re-transmitted to the final receiver for demodulation and beamforming. Real-time adaptive beamformer algorithm is used to compensate for the phase delay difference among drone elements in RF circuitry and in propagation paths caused by different drone elements positions. A beamforming array based on two-drones uses to demonstrate this concept. Improved signal to noise ratio (SNR) has been experimentally demonstrated with such beamforming approach. The proposed beamforming system architecture is expected to extend to a large of number distributed mini-drones for future wireless sensing and communication systems.
{"title":"Experimental Demonstration of Distributed Beamforming on Two Flying Mini-Drones","authors":"J. Diao, M. Hedayati, Y. E. Wang","doi":"10.23919/USNC-URSI-NRSM.2019.8713053","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713053","url":null,"abstract":"Combing distributed small wireless systems on mobile platforms such as swarm airborne mini-drones has been explored recently. Localization and synchronization of the mobile drones are the main challenges limiting its practical applications. In this paper, we proposed a new approach to circumvent this limits by considering the drones as relay nodes, where the received signals are modulated to different frequencies and then re-transmitted to the final receiver for demodulation and beamforming. Real-time adaptive beamformer algorithm is used to compensate for the phase delay difference among drone elements in RF circuitry and in propagation paths caused by different drone elements positions. A beamforming array based on two-drones uses to demonstrate this concept. Improved signal to noise ratio (SNR) has been experimentally demonstrated with such beamforming approach. The proposed beamforming system architecture is expected to extend to a large of number distributed mini-drones for future wireless sensing and communication systems.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121616787","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 : 1900-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8712968
S. H. Hesari, A. Hedayatipour, Shaghayegh Aslanzadeh, S. Islam
This paper presents a design of an ultra low-power operational transconductance amplifier (OTA) intended for biomedical applications and realized in a $0.18 {mu } mathrm {m}$ CMOS technology. The proposed OTA take advantages of bulk-driven (OTA) scheme to reduce power consumption. The OTA uses a single 0.8 V supply and dissipates 5.5 pW of power and provides 70 dB gain which makes it suitable for use as a main block of many biomedical applications including implantable and wearable sensors. The simulation results are compared with conventional OTA structures and some recent works and indicate significant increase in gain while indicating a reduction in power consumption.
本文提出了一种用于生物医学应用的超低功耗操作跨导放大器(OTA)的设计，并以0.18 {mu} math {m}$ CMOS技术实现。所提出的OTA利用了大容量驱动(OTA)方案来降低功耗。OTA使用单个0.8 V电源，功耗为5.5 pW，增益为70 dB，这使得它适合用作许多生物医学应用的主要模块，包括植入式和可穿戴传感器。仿真结果与传统OTA结构和最近的一些研究成果进行了比较，结果表明增益显著增加，功耗降低。
{"title":"Ultra Low-Power OTA for Biomedical Applications","authors":"S. H. Hesari, A. Hedayatipour, Shaghayegh Aslanzadeh, S. Islam","doi":"10.23919/USNC-URSI-NRSM.2019.8712968","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8712968","url":null,"abstract":"This paper presents a design of an ultra low-power operational transconductance amplifier (OTA) intended for biomedical applications and realized in a $0.18 {mu } mathrm {m}$ CMOS technology. The proposed OTA take advantages of bulk-driven (OTA) scheme to reduce power consumption. The OTA uses a single 0.8 V supply and dissipates 5.5 pW of power and provides 70 dB gain which makes it suitable for use as a main block of many biomedical applications including implantable and wearable sensors. The simulation results are compared with conventional OTA structures and some recent works and indicate significant increase in gain while indicating a reduction in power consumption.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129763984","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 : 1900-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8712940
Yuchen Jin, Xuqing Wu, Jiefu Chen, Yueqin Huang
Subsurface inversion is an essential technique for many applications including seismic processing, oilfield well logging an geosteering. Conventional inverse methods based on optimization are time-consuming and sensitive to initial values. The traditional lookup table approach which is limited by the table size could reduce the computational time but only achieves low accuracy. To solve these issues, we propose a physics-driven Deep Neural Network (PhDNN) for solving non-linear inverse problems. In this framework, the physical forward model is utilized to produce a data misfit. Both the model misfit and data misfit are used to train the network. As an example, we use this framework to solve a geosteering problem which enables the drilling direction adjusted by collected resistivity well logging measurements. Numerical tests indicate that the proposed network could improve the quality of the prediction significantly.
{"title":"A Physics-Driven Deep Learning Network for Subsurface Inversion","authors":"Yuchen Jin, Xuqing Wu, Jiefu Chen, Yueqin Huang","doi":"10.23919/USNC-URSI-NRSM.2019.8712940","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8712940","url":null,"abstract":"Subsurface inversion is an essential technique for many applications including seismic processing, oilfield well logging an geosteering. Conventional inverse methods based on optimization are time-consuming and sensitive to initial values. The traditional lookup table approach which is limited by the table size could reduce the computational time but only achieves low accuracy. To solve these issues, we propose a physics-driven Deep Neural Network (PhDNN) for solving non-linear inverse problems. In this framework, the physical forward model is utilized to produce a data misfit. Both the model misfit and data misfit are used to train the network. As an example, we use this framework to solve a geosteering problem which enables the drilling direction adjusted by collected resistivity well logging measurements. Numerical tests indicate that the proposed network could improve the quality of the prediction significantly.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128449093","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 : 1900-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8712941
B. Morshed
Wearable Electrocardiogram (ECG) devices cannot be used for long duration due to power requirement (on a single charge) and electrode degradation. A new extremely low power wearable ECG sensor device is proposed in this work that minimizes power consumption by eliminating digitization and wireless data transfer with a zero power analog inductive coupling and long duration inkjet printed (IJP) dry electrodes. The prototyped device can operate on a coin cell for 140 hours consuming only 1.6 mA. Ability to collect ECG data at home for long duration can largely improve capabilities of mobile health (mHealth) towards Smart and Connected Communities (SCC).
{"title":"Ultra Low-power Inductively Coupled Wearable ECG Sensor Design with Inkjet Printed Dry Electrodes","authors":"B. Morshed","doi":"10.23919/USNC-URSI-NRSM.2019.8712941","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8712941","url":null,"abstract":"Wearable Electrocardiogram (ECG) devices cannot be used for long duration due to power requirement (on a single charge) and electrode degradation. A new extremely low power wearable ECG sensor device is proposed in this work that minimizes power consumption by eliminating digitization and wireless data transfer with a zero power analog inductive coupling and long duration inkjet printed (IJP) dry electrodes. The prototyped device can operate on a coin cell for 140 hours consuming only 1.6 mA. Ability to collect ECG data at home for long duration can largely improve capabilities of mobile health (mHealth) towards Smart and Connected Communities (SCC).","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121124359","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 : 1900-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713166
P. Loghmannia, M. Manteghi
A multipurpose (Wi-Fi, ISM, GPS, and Iridium bands) antenna system for communications over saltwater is introduced. Three antennas including monopole, dipole, and helix are located close to each other within a resin as a radome. In the proposed antenna design, special considerations are taken into account to not only miniaturize the antenna overall size but also maximize antenna gain in the desired directions. A full wave simulator (HFSS) is used to optimize the antenna radiation patterns and return loss for different levels of the seawater. The simulation results illustrate the effectiveness of our design.
{"title":"An Antenna System for Autonomous Underwater Vehicle","authors":"P. Loghmannia, M. Manteghi","doi":"10.23919/USNC-URSI-NRSM.2019.8713166","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713166","url":null,"abstract":"A multipurpose (Wi-Fi, ISM, GPS, and Iridium bands) antenna system for communications over saltwater is introduced. Three antennas including monopole, dipole, and helix are located close to each other within a resin as a radome. In the proposed antenna design, special considerations are taken into account to not only miniaturize the antenna overall size but also maximize antenna gain in the desired directions. A full wave simulator (HFSS) is used to optimize the antenna radiation patterns and return loss for different levels of the seawater. The simulation results illustrate the effectiveness of our design.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133713545","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 : 1900-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8712977
Lingnan Song, Daisong Zhang, Y. Rahmat-Samii
In this paper, we present a study on the effects of stitch density towards the accurate modeling of embroidered textile patch antennas. A detailed full-wave model is used to accurately characterize the embroidery patch antenna with different stitch densities. The model accounts for the double-layer and nonuniform nature of the embroidery pattern. A generalized circuit model linked with particle swarm optimization (PSO) is then utilized to extract the effective circuit parameters and interpret the variations of antenna performance by embroidery stitch densities. The accurate modeling is further validated by systematically designing a low stitch density E-shape patch antenna with satisfactory performance.
{"title":"Towards Embroidered Textile Antenna Systematic Design and Accurate Modeling: Investigation of Stitch Density","authors":"Lingnan Song, Daisong Zhang, Y. Rahmat-Samii","doi":"10.23919/USNC-URSI-NRSM.2019.8712977","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8712977","url":null,"abstract":"In this paper, we present a study on the effects of stitch density towards the accurate modeling of embroidered textile patch antennas. A detailed full-wave model is used to accurately characterize the embroidery patch antenna with different stitch densities. The model accounts for the double-layer and nonuniform nature of the embroidery pattern. A generalized circuit model linked with particle swarm optimization (PSO) is then utilized to extract the effective circuit parameters and interpret the variations of antenna performance by embroidery stitch densities. The accurate modeling is further validated by systematically designing a low stitch density E-shape patch antenna with satisfactory performance.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132338309","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 : 1900-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713102
J. Diao, M. Hedayati, R. Tok, Y. E. Wang
A novel approach by utilizing the fast mechanical rotation of arrays has been proposed for low sidelobe levels by integrating the rotational time-varying radiation pattern in a short time. From the experimental measured radiation pattern for a 4-element circular polarized array antenna with 0.87 element spacing, the mainlobe of the radiation pattern for the rotation array is almost the same as the non-rotation array, while the sidelobe level is decreased by 14.2 dB from the non-rotation array. This technique could be potentially applied for sensing and radar systems that require high SNR and frequency resolution by integrating the received signals within the rotation period.
{"title":"Mechanical Rotating Arrays for Sidelobe Suppression","authors":"J. Diao, M. Hedayati, R. Tok, Y. E. Wang","doi":"10.23919/USNC-URSI-NRSM.2019.8713102","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713102","url":null,"abstract":"A novel approach by utilizing the fast mechanical rotation of arrays has been proposed for low sidelobe levels by integrating the rotational time-varying radiation pattern in a short time. From the experimental measured radiation pattern for a 4-element circular polarized array antenna with 0.87 element spacing, the mainlobe of the radiation pattern for the rotation array is almost the same as the non-rotation array, while the sidelobe level is decreased by 14.2 dB from the non-rotation array. This technique could be potentially applied for sensing and radar systems that require high SNR and frequency resolution by integrating the received signals within the rotation period.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114754179","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 : 1900-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8712950
T. Mealy, Ahmed F. Abdelshafy, F. Capolino
We explore the exceptional point of degeneracy (EPD) at the cutoff of the dominant mode in a uniform rectangular waveguide. We show that the system matrix describing the wave propagation is similar to a Jordan matrix, and we look at the field at the degeneracy point that exhibits algebraic growth along the waveguide as a result of the Jordan matrix description. Field expressions for the dominant mode are derived at the EPD. A numerical example is used to show the degeneracy and its associated field behavior.
{"title":"The Degeneracy of the Dominant Mode in Rectangular Waveguide","authors":"T. Mealy, Ahmed F. Abdelshafy, F. Capolino","doi":"10.23919/USNC-URSI-NRSM.2019.8712950","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8712950","url":null,"abstract":"We explore the exceptional point of degeneracy (EPD) at the cutoff of the dominant mode in a uniform rectangular waveguide. We show that the system matrix describing the wave propagation is similar to a Jordan matrix, and we look at the field at the degeneracy point that exhibits algebraic growth along the waveguide as a result of the Jordan matrix description. Field expressions for the dominant mode are derived at the EPD. A numerical example is used to show the degeneracy and its associated field behavior.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121440462","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 : 1900-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713005
Ramaa Saket Suri, N. Tasneem, I. Mahbub
Wireless power transfer has been studied significantly in the past couple of years for implanted biomedical devices. Due to the extreme power constraints, implantable devices need efficient AC-DC power rectification. This paper presents a low-power rectifier for a wideband wireless power transfer system. The 10-stage rectifier is designed using a standard 130 nm BiCMOS process. The proposed design can rectify voltages as low as 100 mV, which is a low voltage that traditional rectifiers are not able to rectify. The rectifier has a wider frequency operation range of 10 kHz – 100 MHz compared to the previous works where the maximum operating frequency is up to 40–50 MHz. The designed rectifier is able to achieve a power conversion efficiency of 51% with 100 mV 7.25 MHz input signal, which make it highly applicable for the wireless power transfer applications for implantable sensors.
{"title":"Low-Power Highly Efficient Voltage-Boosting Rectifier for Wide-band Inductively-Coupled Power Telemetry","authors":"Ramaa Saket Suri, N. Tasneem, I. Mahbub","doi":"10.23919/USNC-URSI-NRSM.2019.8713005","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713005","url":null,"abstract":"Wireless power transfer has been studied significantly in the past couple of years for implanted biomedical devices. Due to the extreme power constraints, implantable devices need efficient AC-DC power rectification. This paper presents a low-power rectifier for a wideband wireless power transfer system. The 10-stage rectifier is designed using a standard 130 nm BiCMOS process. The proposed design can rectify voltages as low as 100 mV, which is a low voltage that traditional rectifiers are not able to rectify. The rectifier has a wider frequency operation range of 10 kHz – 100 MHz compared to the previous works where the maximum operating frequency is up to 40–50 MHz. The designed rectifier is able to achieve a power conversion efficiency of 51% with 100 mV 7.25 MHz input signal, which make it highly applicable for the wireless power transfer applications for implantable sensors.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115109107","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 : 1900-01-01DOI: 10.23919/USNC-URSI-NRSM.2019.8713008
D. Na, J. L. Nicolini, F. Teixeira
We investigate multipactor effects due to secondary electron emission (SEE) using an electromagnetic particle-in-cell (EM-PIC) algorithm implemented on unstructured grids with the Furman-Pivi probabilistic SEE model. The present EMPIC algorithm yields an energy- and charge-conserving time-update for fields and particles on unstructured grids, from first principles. The Furman-Pivi model enables a realistic description of SEE in EM-PIC simulations. We study the effects of the surface roughness for the reduction of secondary electron yield (SEY) on copper surfaces.
{"title":"Analysis of Multipactor Effects by a Particle-in-Cell Algorithm Coupled with the Furman-Pivi Secondary Electron Emission Model","authors":"D. Na, J. L. Nicolini, F. Teixeira","doi":"10.23919/USNC-URSI-NRSM.2019.8713008","DOIUrl":"https://doi.org/10.23919/USNC-URSI-NRSM.2019.8713008","url":null,"abstract":"We investigate multipactor effects due to secondary electron emission (SEE) using an electromagnetic particle-in-cell (EM-PIC) algorithm implemented on unstructured grids with the Furman-Pivi probabilistic SEE model. The present EMPIC algorithm yields an energy- and charge-conserving time-update for fields and particles on unstructured grids, from first principles. The Furman-Pivi model enables a realistic description of SEE in EM-PIC simulations. We study the effects of the surface roughness for the reduction of secondary electron yield (SEY) on copper surfaces.","PeriodicalId":142320,"journal":{"name":"2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125082243","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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