2016
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A Compact Ultra-Wideband Bandpass Filter with Sharp-Rejection using Complementary Split Ring Resonators
A Compact Ultra-Wideband Bandpass Filter with Sharp-Rejection using Complementary Split Ring Resonators
2
2
A compact and sharp-rejection ultra-wideband (UWB) microstrip band-pass filter (BPF) is developed using of left handed metamaterials realized by complementary split ring resonator (CSRR). Moreover, proposed structure consists of two doublets parallel coupling gaps at each side of a microstrip ring. In comparison with some other filters, this structure shows a significantly wider passband due to the introduction of a cross-coupling between the feed lines (input and output) which generate four pairs of attenuation poles in the passband.On top of that, using two CSRRs etched in the back substrate side,and series gap inside the microstrip ring leads to the addition of two extra transmission poles at the lower and upper edges of the filter.Consequently, a compact six-pole ultra-wide bandpass filter is designed which exhibits extremely sharp rejection skirts around the target passband.The proposed filter has a passband covers3.4 to 10.15GHz andits measured 3dB fractional bandwidth is about 100%. Furthermore, rejection level better than 20 dB in upper stopband is extended to around 15.2 GHz both in simulation and measurement. Experimental verification is provided and good agreement has been found between simulation and measurement. To our knowledge, the size of proposed ultra-wideband filter is more compact in comparison with known similar filters.
1
A compact and sharp-rejection ultra-wideband (UWB) microstrip band-pass filter (BPF) is developed using of left handed metamaterials realized by complementary split ring resonator (CSRR). Moreover, proposed structure consists of two doublets parallel coupling gaps at each side of a microstrip ring. In comparison with some other filters, this structure shows a significantly wider passband due to the introduction of a cross-coupling between the feed lines (input and output) which generate four pairs of attenuation poles in the passband.On top of that, using two CSRRs etched in the back substrate side,and series gap inside the microstrip ring leads to the addition of two extra transmission poles at the lower and upper edges of the filter.Consequently, a compact six-pole ultra-wide bandpass filter is designed which exhibits extremely sharp rejection skirts around the target passband.
1
10
Mostafa
Danaeian
Mostafa
Danaeian
Department of Electrical Engineering, Shahid Bahonar University of Kerman, Kerman, Iran.
Department of Electrical Engineering, Shahid
Iran
mdanaeian@eng.uk.ac.ir
Masoud
Movahhedi
Masoud
Movahhedi
Electrical and Computer Engineering Department, Yazd University, Yazd, Iran.
Electrical and Computer Engineering Department,
Iran
movahhedi@yazd.ac.ir
Ahmad
Hakimi
Ahmad
Hakimi
Department of Electrical Engineering, Shahid Bahonar University of Kerman, Kerman, Iran.
Department of Electrical Engineering, Shahid
Iran
hakimi@uk.ac.ir
Kambiz
Afrooz
Kambiz
Afrooz
Department of Electrical Engineering, Shahid Bahonar University of Kerman, Kerman, Iran
Department of Electrical Engineering, Shahid
Iran
afrooz@uk.ac.ir
Complementary split ring resonator (CSRR)
ultra-wideband (UWB)
bandpass filter(BPF)
microstrip ring
doublets parallel coupling gaps
[[1] Federal Communications Commission, Revision of part 15 of the Commission’s rules regarding ultra-wideband transmission systems, Tech. Rep., ET-Docket 98-153, FCC02-48, April, 2002.##[2] D. Jung, J. Lee, and K. Chang, “Wideband Bandpass Filter Using Microstrip Ring,” Microwave and Optical Technology Letters, vol. 53, no. 1, January, 2011.##[3] Z. Ma, W. He, C. Chen, Y. Kobayashi, and T. Anada, “A Novel Compact Ultra-Wideband Bandpass Using Stub-Loaded Dual-Mode Resonator Doublets,” in Microwave Symposium Digest (IMS) Proc., pp. 435-438, 26 September, 2008.##[4] L. Zhu, K. Wu, A joint field/circuit model of line-to-ring coupling structures and its application to the design of microstrip dual-mode filters and ring resonator circuits, IEEE Trans. Microwave Theory Tech. 47 (10), pp. 1938–1948, 1999.##[5] L.H. Hsieh, K. Chang, Dual-mode quasi-elliptic-function bandpass filters using ring resonators with enhanced-coupling tuning stubs, IEEE Trans. Microwave Theory Tech. 50 (5), pp. 1340–1345, 2002.##[6] S. Sun, L. Zhu, Wideband microstrip ring resonator bandpass filters under multiple resonances, IEEE Trans. Microwave Theory Tech. 55 (10), pp. 2176–2182, 2007.##[7] C.H. Kim, K. Chang, Ultra-wideband (UWB) ring resonator bandpass filter with a notched band, IEEE Microwave Wireless Compon. Lett. 21 (4), pp. 206–208, 2011.##[8] C. H. Kim and K. Chang, “Ring resonator bandpass filter with switchable bandwidth using stepped-impedance stubs,” IEEE Trans. Microw. Theory Tech., vol. 58, no. 12, pp. 3936–3944, December, 2010.##[9] A. Nakhlestani, A. Hakimi “Wideband microstrip ring resonator bandpass filter with embedded rings” Microelectronics Journal, no.5, pp. 462-467, 2013.##[10] R. Marque’s, F. Martin and M. Sorolla, Metamaterials with Negative Parameters, First Edition, John Wiley Co., 2006.##[11] M. Gil, J. Bonache, J. Garcia-Garcia, J. Martel, and F. Martin “Composite right/left handed (CRLH) metamaterial transmission lines based on complementary split rings resonators (CSRRs) and their Applications to very wide band and compact filter design.” IEEE Trans. Microwave Theory Tech., vol. 55, pp. 1296–1304, June, 2007.##[12] Bonache J, Martin F, Garcia‐Garcia J, Gil I, Marques R, Sorolla M. Ultra-wide band pass filters (UWBPF) based on complementary split rings resonators. Microwave and optical technology letters. 5; 46(3):283-6, Aug, 2005.##[13] M. Gil, J. Bonache, and F. Martin “Metamaterial filters with attenuation poles in the pass band for ultra-wide band applications” Microwave Opt. Tech. Lett., vol. 49, pp. 2909–2913, December, 2007.##[14] Tu WH. Sharp-rejection broadband microstrip bandpass filter using penta-mode resonator. Group. 27; 1(2.0):2-4, May, 2010.##[15] P. Mondal, M. Mandal, A. Chakrabarty, “Compact Ultra-Wideband Bandpass Filter with Improved Upper Stopband,” IEEE Microwave and Wireless Components Letter, vol. 17, No.9, September, 2007.##[16] D. Chen, X. D. Huang, and C. H. Cheng, “A Novel Compact Ultra-Wideband (UWB) Bandpass Filter Using Multiple-Mode Resonator,” Microwave And Optical Technology Letters, vol. 51, No.7, July, 2009.##[17] H. H. Hu, Z. Y. Xiao, W. Q. He and S. Gao “Novel Compact Ultra-Wideband Filter with Wide Stop Band,” Microwave and Optical Technology Letters, vol. 51, No.1, January, 2009.##[18] Zhewang Ma, H. Sasaki, Ch.P. Chen, T. Anada, and Y. Kobayashi, “Design of a Wideband Bandpass Filter Using Microstrip Parallel- Coupled Dual-Mode Ring Resonator” Asia-Pacific Microwave Conference Proceedings, pp. 21-24, December, 2010.##[19] P. Cai, Z. Ma, X. Guan, Y. Kobayashi and T. Anada, “Novel Compact microstrip dual-mode ring resonator wideband Bandpass filter with significantly improved stopband property,” IEICE Trans Electron., no. 12, pp. 1858-1864, December, 2006.##[20] He Zhu , Qing-Xin Chu, “Compact Ultra-Wideband (UWB) Bandpass Filter Using Dual-Stub-Loaded Resonator (DSLR),” IEEE Microwave and Wireless Components Letter vol. 23, No.10, October, 2013.##[21] Pozar, David M. "Microwave Engineering, copyright 2012 by John Wiley & Sons." 422-426.##[22] Ishida, H., & Araki, K. “Design and analysis of UWB bandpass filter with ring filter,” IEEE MTT-S Int. Dig., no. 3, pp. 1307–1310, 2004.##[23] Q. X. Chu, X. H. Wu, and X. K. Tian, “Novel UWB bandpass filter Using stub-loaded multiple-mode resonator,” IEEE Microwave Wireless Components Letters, vol. 21, no. 8, pp. 403–405, Aug, 2011.##[24] Wu, H. W., Chen, Y. W., & Chen, Y. F. “New ultra-wideband (UWB) bandpass filter using triangle-ring multi-mode stub-loaded resonator,” Microelectronics Journal, vol. 43, no. 11, pp. 857–862, November, 2012.##[25]J. S. Hong, Microstrip Filters for RF/Microwave Application, 2nd Edition, John Wiley & Sons, Inc., 2011.##[26] Sahin EG, Gorur AK, Karpuz C, Gorur A. Design of UWB microstrip bandpass filter using stub‐loaded quintuple‐mode resonator. Microwave and Optical Technology Letters. pp. 662-666, Mar, 2016.##[27] Lu X, Wei B, Xu Z, Cao B, Guo X, Zhang X, Wang R, Song F. “Superconducting Ultra-Wideband (UWB) Bandpass Filter Design Based on Quintuple/Quadruple/Triple-Mode Resonator.” Microwave Theory and Techniques, IEEE Transactions on, pp. 1281-1293, Apr, 2015. ##]
Electrostatic analysis of the charged surface in a solution via the finite element method: The Poisson-Boltzmann theory
Electrostatic analysis of the charged surface in a solution via the finite element method: The Poisson-Boltzmann theory
2
2
Electrostatic potential as well as the local volume charge density are computed for a macromolecule by solving the Poisson-Boltzmann equation (PBE) using the finite element method (FEM). As a verification, our numerical results for a one dimensional PBE, which corresponds to an infinite-length macromolecule, are compared with the existing analytical solution and good agreement is found. As a macromolecule has a rod-like shape with a finite length, a much more real case is considered, which leads to a two dimensional PBE. Furthermore, it is demonstrated that the potential and charge density decrease as the distance from the axis of the macromolecule increases. Moreover, it is concluded that the absolute value of the electrostatic field obtained from the nonlinear PBE subject to the boundary condition with a fixed charge differs from that of the linear PBE at fixed potential by an order of magnitude in the vicinity of the finite rod-like macromolecule. On the other hand, excellent agreement is observed between the electric fields calculated from the aforementioned equations at far distances.
1
Electrostatic potential as well as the local volume charge density are computed for a macromolecule by solving the Poisson-Boltzmann equation (PBE) using the finite element method (FEM). As a verification, our numerical results for a one dimensional PBE, which corresponds to an infinite-length macromolecule, are compared with the existing analytical solution and good agreement is found. As a macromolecule has a rod-like shape with a finite length, a much more real case is considered, which leads to a two dimensional PBE. Furthermore, it is demonstrated that the potential and charge density decrease as the distance from the axis of the macromolecule increases. Moreover, it is concluded that the absolute value of the electrostatic field obtained from the nonlinear PBE subject to the boundary condition with a fixed charge differs from that of the linear PBE at fixed potential by an order of magnitude in the vicinity of the finite rod-like macromolecule. On the other hand, excellent agreement is observed between the electric fields calculated from the aforementioned equations at far distances.
11
17
Shaghayegh
Nikzad
Shaghayegh
Nikzad
Department of Energy Engineering and Physics, Amirkabir University of Technology (Tehran Polytechnic), Hafez Avenue, Tehran, Iran
Department of Energy Engineering and Physics,
Iran
sh.nikzad@aut.ac.ir
Houshyar
Noshad
Houshyar
Noshad
Amirkabir University of Technology
Amirkabir University of Technology
Iran
hnoshad@aut.ac.ir
Poisson-Boltzmann equation
Finite Element Method
polyelectrolyte
reduced electrostatic potential
[[1] Holm, C., Kekicheff, P., Podgornik, R.,“Electrostatic Effects in Soft Matter and Biophysics”, Kluwer Academic, Dordrecht, 2001.##[2] Poon, W.C.K., Andelman, D., “Soft condensed matter physics in molecular and cell biology”, Taylor##& Francis, New York: London, 2006.##[3] Oosawa, F., “Polyelectrolytes”, Marcel Dekker, New York, 1971.##[4] Naji, A., Kanduc, M., Netz, R.R., Podgornik, R., “Exotic Electrostatics: Unusual Features of Electrostatic Interactions between Macroions. In:Andelman D and Reiter G (eds) Understanding Soft Condensed Matter via Modeling and Computation”,World Scientific, Singapore, 2010.##[5] Mandel, M., “The electric polarization of rod-like,charged Macromolecules”, J. Mol. Phys, 4: pp 489-##496, 1961.##[6] French, R.H et al., “Long range interactions innanoscale science”, Rev. Mod. Phys, 82: pp 1887-##1944, 2010.##[7] Li, Y., Yang, M.J., She, Y., “Humidity sensitiveproperties of crosslinked and quaternized Poly (4-##vinylpyridine-co-butyl methacrylate)”, Sensors andActuators B, 107: pp 252–257, 2005.##[8] Harrey, P.M., Ramsey, B.J., Evans, P.S.A., Harrison,D.J., “Capacitive-type humidity sensors fabricated##using the offset lithographic printing process”,Sensors and Actuators B, 87: pp 226–232, 2002.##[9] Hossain, R., Adamiak, K., “Dynamic properties ofthe electric double layer in electrolytes”, J. Electrost,##71: pp 829-838, 2010.##[10] Honig, B., Nicholls, A., “Classical electrostatics inbiology and chemistry”, Science, 268: pp 1144-##1149, 1995.##[11] Rocchia, W., Alexov, E., Honig, B., “Extending theApplicability of the Nonlinear Poisson−Boltzmann##Equation: Multiple Dielectric Constants andMultivalent Ions”, J. Phys. Chem, 105: pp 6507-##6514, 2001.##[12] Butt, H-J., Graf, K., Kappl, M., “Physics andChemistry of Interfaces”, Weinheim: Wiley-VCH,##[13] Israelachvili, J.N., “Intermolecular and SurfaceForces: With Applications to Colloidal and##Biological Systems”, Academic Press, London,1985.##[14] Vander Vorst, A., Rosen, A., Kotsuka, Y.,“RF/Microwave Interaction with BiologicalTissues”, IEEE Press, 2006.##[15] Shestakov, A. I., Milovich, J. L., Noy, A., “Solutionof the nonlinear Poisson–Boltzmann equation using##pseudo-transient continuation and the finite elementmethod”, J. Colloid Interface Sci, 247: pp 62–79,##[16] Chapot, D., Bocquet, L., Trizac, E., “Electrostaticpotential around charged finite rod-like##macromolecules: nonlinear Poisson–Boltzmann theory”, J. Colloid Interface Sci, 285: pp 609-618, 2005.##[17] Sadiku, M.N.O., “A simple introduction to finite element analysis of electromagnetic problems,” IEEE Trans. Educ, 32: pp 85–93, 1989.##[18] Le Bret, M., Zimm, B.H., “Distribution of counter ions around a cylindrical polyelectrolyte and Manning‟s condensation theory”, Biopolymers, 23: pp 287-312, 1984.##[19] Zangwill, A., “Modern electrodynamics”, Cambridge University Press, 2012.##[20] Yoshida, M., Kikuchi, K., Maekawa, T., Watanabe, H., “Electric polarization of rod-like polyions investigated by Monte Carlo simulations”, J. Phys. Chem, 96: pp 2365-2371, 1992.##[21] Washizu, H., Kikuchi, K., “Electric polarizability of DNA in aqueous salt solution”, J. Phys. Chem. B, 110: pp 2855-2861, 2006.##[22] Deserno, M., Holm, C., May, S., “The fraction of condensed counter ions around a charged rod: Comparison of Poisson-Boltzmann theory and computer simulations”, Macromolecules, 33: pp 199-206, 2000.##[23] Fuoss, R., Katchalsky, A., Lifson, S., “The potential of an infinite rod-like molecule and the distribution of the counter ions”, Proc Natl Acad Sci (Wash), 37: pp 579-589, 1951.##[24] Alfrey, T., Berg, P., Morawetz, H., “The Counter ion Distribution in Solutions of Rod-Shaped Polyelectrolytes”, J. Polym. Sci, 7: pp 543-547, 1951.##[25] Bocquet, L., Trizac, E., Aubouy, M., “Effective charge saturation in colloidal suspensions”, J. Chem. Phys, 117: pp 8138-8152, 2002.##[26] Trizac, E., Bocquet, L., Aubouy, M., “Simple approach for charge renormalization in highly charged macroions”, Phys. Rev. Lett, 89: pp 248301(1)-4, 2002. ##]
Improving Long PN-Code Acquisition in the Presence of Doppler Frequency Shifts
Improving Long PN-Code Acquisition in the Presence of Doppler Frequency Shifts
2
2
Wireless communication is the major form of connection nowadays. In most cases it exploits the benefits of the spread spectrum techniques to overcome channel introduced corruptions like Doppler residual frequency, noise, interference and jamming. These techniques also enhance the security and quality of the link. Using long spreading pseudo-noise codes provides further security for the link though its acquisition is challenging. In this paper we propose Enhanced Dual Folding method for acquiring long codes in high Doppler scenarios. Two main criteria of an acquisition algorithm i.e. probability of detection and mean acquisition time is theoretically and numerically obtained for the proposed method. The proposed method's performance is simulated for two Doppler residual frequencies and is compared with a similar technique of long code acquisition which confirms the success of the proposed method in tolerating high Doppler in comparison with the similar technique. The simulation results agree well with the theoretical equations.
1
Wireless communication is the major form of connection nowadays. In most cases it exploits the benefits of the spread spectrum techniques to overcome channel introduced corruptions like Doppler residual frequency, noise, interference and jamming. These techniques also enhance the security and quality of the link. Using long spreading pseudo-noise codes provides further security for the link though its acquisition is challenging. In this paper we propose Enhanced Dual Folding method for acquiring long codes in high Doppler scenarios. Two main criteria of an acquisition algorithm i.e. probability of detection and mean acquisition time is theoretically and numerically obtained for the proposed method. The proposed method's performance is simulated for two Doppler residual frequencies and is compared with a similar technique of long code acquisition which confirms the success of the proposed method in tolerating high Doppler in comparison with the similar technique. The simulation results agree well with the theoretical equations.
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27
Maryam
Borna
Maryam
Borna
PhD. Student, Communications Engineering Faculty, Malek Ashtar University of Technology, Tehran, Iran.
PhD. Student, Communications Engineering
Iran
maryam.borna@gmail.com
Mohammad Hossein
Madani
Mohammad Hossein
Madani
Associate Professor, Communications Engineering Faculty, Malek Ashtar University of Technology, Tehran, Iran.
Associate Professor, Communications Engineering
Iran
mh_madani@aut.ac.ir
DSSS
Long PN-code Acquisition
Doppler
Folding
Zero padding
[[1] R. E. Ziemer, R. L. Peterson and D. E. Borth,Introduction to Spread Spectrum Communications,##Prentice Hall, 1995.##[2] V. P. Ipatov, Spread Spectrum and CDMA:Principles and Applications, John Wiley, 2005.##[3] E. D. Kaplan and C. J. Hegarty, Understanding GPS:Principles and Applications, London: Artech House,##[4] S. H. Kong and B. Kim, "Two-DimensionalCompressed Correlator for Fast PN CodeAcquisition," Wireless Communications, IEEETransactions on, vol. 12, no. 11, pp. 5859-5867,##[5]B. Kim and S. H. Kong, "Two-Dimensional Compressed Correlator for Fast Acquisition of Signals," Vehicular Technology, IEEE Transactions on, vol. 63, no. 6, pp. 2662-2672, 2014.##[6]B. Kim and S. H. Kong, "Determination of detection parameters on TDCC performance," Wireless Communications, IEEE Transactions on, vol. 13, no. 5, pp. 2422-2431, 2014.##[7]K. M. Chugg and M. Zhu, "A New Approach to Rapid PN Code Acquisition Using Iterative Message Passing Techniques," IEEE Journal on Selected Areas in Communications, vol. 23, pp. 884-898, 2005.##[8]O. W. Yeung and K. M. Chugg, "A Low Complexity Circuit Architecture for Rapid PN Code Acquisition in UWB Systems Using Iterative Message Passing on Redundant Graphical Models," University of Southern California, 2005.##[9]J. Zhang, Y. Pei and N. Ge, "PN Code Acquisition Using Belief Propagation with Adaptive Parity Check Matrix," Wireless personal communications, vol. 71, no. 4, pp. 3105-3113, 2013.##[10]L. Hong, X. C. Mingquan Lu and F. Zhenming, "Generalized Zero-Padding Scheme for Direct P-Code Acquisition," IEEE Transactions on Wireless Communications, vol. 8, no. 6, pp. 2866-72, 2009.##[11]J. Ping, X. Wu, Y. Jun and W. Zhu, "Modified Zero-Padding Method for Fast Long PN-Code Acquisition," in Vehicular Technology Conference (VTC Fall), 2014 IEEE 80th, 2014.##[12]L. Simone and G. Fittipaldi, "Fast acquisition techniques for very long PN codes for on-board secure TTC transponders," in MILITARY COMMUNICATIONS CONFERENCE, 2011-MILCOM 2011, 2011.##[13]J. A. Starzyk and Z. Zhu, "Averaging correlation for C/A code acquisition and tracking in frequency domain," Proc. IEEE Midwest Sym. on Circuits and Systems (MWSCAS), vol. 2, pp. 905-908, 2001.##[14]J. Pang, F. Van Grass, J. Starzyk and Z. Zhu, "Fast Direct GPS P-Code Acquisition," GPS Solutions, vol. 7, no. 3, pp. 168-175, 2003.##[15]L. Hong, L. Minguan and Z. Feng, "Mathematical Modelling and Performance Analysis for Average-Based Rapid Search Method for Direct Global Position System Precision Code Acquisition," IET Radar Sonar and Navigation, vol. 3, no. 1, pp. 81-93, 2009.##[16]C. Yang, J. Vasquez and J. Chaffee, "Fast Direct P(Y)-code Acquisition Using XFAST," in Proceedings of the 12th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GPS 1999), Nashville, TN, 1999.##[17]L. Hong, C. Xiaowei, M. Lu and F. Zhenming, "Dual-Folding Based Rapid Search Method for Long PN-Code Acquisition," IEEE Transactions on Wireless Communications, vol. 7, no. 12, pp. 5286-5297, 2008.##[18]J. Baek, J. Park, Y. Lee, S. Y. Kim, G.-I. Jee, J.-M. Yang and S. Yoon, "Low Complexity Long PN Code Acquisition Scheme for Spread Spectrum Systems," in The Third International Conference on Emerging Network Intelligence, 2011.##[19]L. Hong, L. Mingquan and F. Zhenming, "Partial-Correlation-Result Reconstruction Technique for Weak Global Navigation Satellite System Long Pseudo-Noise-Code Acquisition," IET Radar, Sonar and Navigation, vol. 5, no. 7, pp. 731-740, 2011.##[20]L. Hong, L. Mingquan and F. Zhenming, "Three-Stage Based Rapid Long PN-code Acquisition Method by Employing Time-Frequency Folding Technique," Chinese Journal of Electronics, vol. 19, no. 4, 2010.##[21]H. Li, M. Lu and Z. Feng, "Mapping and overlapping based carrier frequency searching technique for rapid GNSS long PN-code acquisition," Science China Information Sciences, vol. 53, no. 12, pp. 2642-2652, 2010.##[22]F. Wenquan, X. Xiaodi, Z. Qi and Z. W, "Local Frequency Folding Method for Fast PN-Code Acquisition," IEICE Transactions on Communications, vol. 97, no. 5, pp. 1072-1079, 2014.##[23]M. Sahmoudi, M. G. Amin and R. Landry Jr, "Acquisition of weak GNSS signals using a new block averaging pre-processing," in Position, Location and Navigation Symposium, 2008 IEEE/ION, 2008.##[24]S. H. Kong, "SDHT for Fast Detection of Weak GNSS Signals," Selected Areas in Communications, IEEE Journal on, vol. 33, no. 11, pp. 2366-2378, 2015.##[25]P. J. G and D. K. Manolakis, Digital Signal Processing Principles, Algorithms and Applications, 4th ed., Prentice Hall, 2007.##[26]N. l. Ziedan, GNSS receivers for weak signals, Artech House, 2006.##[27]S. W. Golomb, Shift Register Sequences, San Fransico, CA: Holden Day, 1967.##[28]P. A. and G. L. Weber, "A unified approach to serial search spread-spectrum code acquisition-part I & II," IEEE Transaction Communications, vol. 32, no. 5, pp. 542-560, 1984. ##]
Dynamic Harmonic Analysis of Long Term over Voltages Based on Time Varying Fourier series in Extended Harmonic Domain
Dynamic Harmonic Analysis of Long Term over Voltages Based on Time Varying Fourier series in Extended Harmonic Domain
2
2
Harmonics have become an important issue in modern power systems. The widespread penetration of non-linear loads to emerging power systems has turned power quality analysis into an important operation issue under both steady state and transient conditions. This paper employs an Extended Harmonic Domain (EHD) based framework for dynamic analysis of long term analysis over voltages during the transients caused by inrush currents while large power factor capacitors are located at transformer secondary side. In such cases, a combination of capacitor and inductive system impedance may lead to parallel resonance circuits of high impedance. As a significance of the developed method, it is fully frequency domain dependent solution technique which uses time dependent Fourier series, orthogonal bases and matrix operators as addressed in EHD. The proposed method has been successfully tested on several networks and the obtained results are compared to those of a time-domain software, followed by discussion on results.
1
Harmonics have become an important issue in modern power systems. The widespread penetration of non-linear loads to emerging power systems has turned power quality analysis into an important operation issue under both steady state and transient conditions. This paper employs an Extended Harmonic Domain (EHD) based framework for dynamic analysis of long term analysis over voltages during the transients caused by inrush currents while large power factor capacitors are located at transformer secondary side. In such cases, a combination of capacitor and inductive system impedance may lead to parallel resonance circuits of high impedance. As a significance of the developed method, it is fully frequency domain dependent solution technique which uses time dependent Fourier series, orthogonal bases and matrix operators as addressed in EHD. The proposed method has been successfully tested on several networks and the obtained results are compared to those of a time-domain software, followed by discussion on results.
29
39
Ehsan
Karami
Ehsan
Karami
Msc. Student, Department of Electrical Engineering, Amirkabir University of Technology, Tehran, Iran.
Msc. Student, Department of Electrical Engineering
Iran
ehsankarami1370@yahoo.com
Shahram
Montaser Kouhsari
Shahram
Montaser Kouhsari
Professor, Department of Electrical Engineering, Amirkabir University of Technology, Tehran, Iran.
Professor, Department of Electrical Engineering,
Iran
smontom@aut.ac.ir
Seyed Mahdi
Mazhari
Seyed Mahdi
Mazhari
PhD. Student, Department of Electrical Engineering, Amirkabir University of Technology, Tehran, Iran
PhD. Student, Department of Electrical Engineering
Iran
mazhari@aut.ac.ir
Capacitor bank
Extended harmonic domain
Inrush current
Transformer
Windowed fast Fourier transform
[[1] E. Acha and M. Madrigal, Power Systems Harmonics: Computer Modelling and Analysis. John Wiley & Sons, 2001.##[2] G. Chang, C. Hatziadoniu, W. Xu, P. Ribeiro, R. Burch, W. M. Grady, M. Halpin, Y. Liu, S. Ranade, D. Ruthman, N. Watson, T. Ortmeyer, J. Wikston, A. Medina, A. Testa, R. Gardinier, V. Dinavahi, F. Acram, and P. Lehn, “Modeling devices with nonlinear Voltage-current Characteristics for harmonic studies,” IEEE Trans. Power Deliv., vol. 19, no. 4, pp. 1802–1811, Oct. 2004.##[3] L. F. Blume, G. Camilli, S. B. Farnham, and H. A. Peterson, “Transformer magnetizing inrush currents and influence on system operation,” Trans. Am. Inst. Electr. Eng., vol. 63, no. 6, pp. 366–375, Jun. 1944.##[4] J. F. Witte, F. P. DeCesaro, and S. R. Mendis, “Damaging long-term overvoltages on industrial capacitor banks due to transformer energization inrush currents,” IEEE Trans. Ind. Appl., vol. 30, no. 4, pp. 1107–1115, 1994.##[5] G. T. Heydt, P. S. Fjeld, C. C. Liu, D. Pierce, L. Tu, and G. Hensley, “Applications of the windowed FFT to electric power quality assessment,” IEEE Trans. Power Deliv., vol. 14, no. 4, pp. 1411–1416, 1999.##[6] J. G. Proakis and D. G. Manolakis, Digital Signal Processing: Principles, Algorithms, and Applications. Simon & Schuster Books For Young Readers, 1992.##[7] E. Acha, “Modeling of Power System Transformers in the Complex Conjugate Harmonic Domain Space,” Ph.D. dissertation, Univ. Canterbury, 1988.##[8] G. N. Bathurst, B. C. Smith, N. R. Watson, and J. Arrillaga, “Modelling of HVDC transmission systems in the harmonic domain,” IEEE Trans. Power Deliv., vol. 14, no. 3, pp. 1075–1080, Jul. 1999.##[9] G. N. Bathurst, N. R. Watson, and J. Arrillaga, “Modeling of bipolar HVDC links in the harmonic domain,” IEEE Trans. Power Deliv., vol. 15, no. 3, pp. 1034–1038, Jul. 2000.##[10] C. S. Bruce, “A Harmonic Domain Model for the Interaction of the HVdc Converter with AC and DC Systems,” Ph.D. dissertation, Univ. Canterbury, 1996.##[11] M. Madrigal, “Modelling of Power Electronics Controllers for Harmonic Analysis in Power Systems,” Ph.D. dissertation, Univ. Glasgow, 2001.##[12] L. T. G. Lima, A. Semlyen, and M. R. Iravani, “Harmonic domain periodic steady state modeling of power electronics apparatus: SVC and TCSC,”IEEE Trans. Power Deliv., vol. 18, no. 3, pp. 960–967, Jul. 2003.##[13] H. García, M. Madrigal, B. Vyakaranam, R. Rarick, and F. E. Villaseca, “Dynamic companion harmonic circuit models for analysis of power systems with embedded power electronics devices,” Electr. Power Syst. Res., vol. 81, no. 2, pp. 340–346, Feb. 2011.##[14] M. Madrigal and E. Acha, “Modelling of custom power equipment using harmonic domain techniques,” in Ninth International Conference on Harmonics and Quality of Power. Proceedings, 2000, vol. 1, pp. 264–269.##[15] C. D. Collins, G. N. Bathurst, N. R. Watson, and A. R. Wood, “Harmonic domain approach to STATCOM modelling,” IEE Proc. - Gener. Transm. Distrib., vol. 152, no. 2, p. 194, Mar. 2005.##[16] C. D. Collins, N. R. Watson, and A. R. Wood, “Unbalanced SSSC modelling in the harmonic domain,” in 2005 International Power Engineering Conference, 2005, pp. 705–710 Vol. 2.##[17] C. D. Collins, “FACTS device modeling in the harmonic domain,” Ph.D. dissertation, Univ. Canterbury, 2006.##[18] C. Collins, N. Watson, and A. Wood, “UPFC Modeling in the Harmonic Domain,” IEEE Trans. Power Deliv., vol. 21, no. 2, pp. 933–938, Apr. 2006.##[19] M. Caixba and A. Ramirez, “A frequency-domain equivalent-based approach to compute periodic steady-state of electrical networks,” Electr. Power Syst. Res., vol. 125, pp. 100–108, Aug. 2015.##[20] J. J. Rico, M. Madrigal, and E. Acha, “Dynamic harmonic evolution using the extended harmonic domain,” IEEE Trans. Power Deliv., vol. 18, no. 2, pp. 587–594, Apr. 2003.##[21] M. Madrigal and J. J. Rico, “Operational Matrices for the Analysis of Periodic Dynamic Systems,” IEEE Trans. Power Syst., vol. 19, no. 3, pp. 1693–1695, Aug. 2004.##[22] P. Zuniga-Haro, “Harmonic Modeling of multi-pulse SSSC,” in 2009 IEEE Bucharest PowerTech, 2009, pp. 1–8.##[23] B. Vyakaranam and F. E. Villaseca, “Dynamic modeling and analysis of generalized unified power flow controller,” Electr. Power Syst. Res., vol. 106, pp. 1–11, 2014.##[24] J. J. Chavez, A. Ramirez, and V. Dinavahi, “Dynamic harmonic domain modelling of synchronous machine and transmission line interface,” IET Gener. Transm. Distrib., vol. 5, no. 9, p. 912, Sep. 2011.##[25] J. J. Chavez and A. Ramirez, “Dynamic Harmonic Domain Modeling of Transients in Three-Phase Transmission Lines,” IEEE Trans. Power Deliv., vol. 23, no. 4, pp. 2294–2301, Oct. 2008.##]
Analysis of Reliability Indices in Next Generation Microgrids Under Uncertainties of Load and Renewable Power Production
Analysis of Reliability Indices in Next Generation Microgrids Under Uncertainties of Load and Renewable Power Production
2
2
In this paper, Multi-Microgrids (MMG) are considered as future smart distribution grids, in which small scale energy resources (SSER) are main power generation units with small scales. Optimal operation of microgrids in defined intervals is carried out to achieve economic conditions in distribution systems. The defined operating problem is optimized using a heuristic algorithm considering uncertainties in loads and renewable energy resources (RERs). The probability density functions (PDFs) are used to encounter with the uncertainties. The total cost of the network is minimized by the algorithm. Then, each MG is evaluated from reliability point of view. Some new introduced reliability indices in the literature for MGs are used to evaluate the MGs' reliability. In proposed structure, the MGs are in interconnected mode and there is power exchanging between MGs. The particle swarm optimization (PSO) algorithm is applied to optimal power dispatch and the obtained results are compared by Monte Carlo simulation (MCS) method.
1
In this paper, Multi-Microgrids (MMG) are considered as future smart distribution grids, in which small scale energy resources (SSER) are main power generation units with small scales. Optimal operation of microgrids in defined intervals is carried out to achieve economic conditions in distribution systems. The defined operating problem is optimized using a heuristic algorithm considering uncertainties in loads and renewable energy resources (RERs). The probability density functions (PDFs) are used to encounter with the uncertainties. The total cost of the network is minimized by the algorithm. Then, each MG is evaluated from reliability point of view. Some new introduced reliability indices in the literature for MGs are used to evaluate the MGs' reliability. In proposed structure, the MGs are in interconnected mode and there is power exchanging between MGs. The particle swarm optimization (PSO) algorithm is applied to optimal power dispatch and the obtained results are compared by Monte Carlo simulation (MCS) method.
41
51
nima
nikmehr
nima
nikmehr
Msc. Student, Smart Distribution grid Research Lab, Azarbaijan Shahid Madani University, Tabriz, Iran.
Msc. Student, Smart Distribution grid Research
Iran
nima.alamdari@yahoo.com
Sajad
Najafi Ravadanegh
Sajad
Najafi Ravadanegh
Associate Professor, Smart Distribution grid Research Lab, Azarbaijan Shahid Madani University, Tabriz, Iran
Associate Professor, Smart Distribution grid
Iran
s.najafi@azaruniv.edu
Optimal Operation
Multi-Microgrids
Reliability Evaluation
Uncertainty
[[1] N. Hatziargyriou, H. Asano, R. Iravani, and C.Marnay, “Microgrids,” IEEE Power Energy Mag., vol.##5, no. 4, pp. 78–94, Jul.–Aug. 2007.##[2] R. H. Lasseter, “MicroGrids,” in Proc. IEEE PowerEng. Soc. Winter Meeting, Jan. 27–31, 2002, vol. 1,##pp. 305–308.##[3] N. Nikmehr, and S. Najafi-Ravadanegh, “A study onoptimal power sharing in interconnected microgrids##under uncertainty,” International Transactions onElectrical Energy Systems, vol. 26, no. 1, pp. 208–##232, 2015.##[4] J. Teng, Y. Liu, C. Chen, and C.-F. Chen, “Valuebaseddistributed generator placements for service##quality improvements,” Int. J. Elect. Power EnergySyst., vol. 29, no. 3, pp. 268–274, Mar. 2007.##[5] C. A. Hernandez-Aramburo, T. C. Green, and N.Mugniot, “Fuel consumption minimization of a##microgrid,” IEEE Trans. Ind. Appl., vol. 41, no. 3, pp.673–681, May/Jun. 2005.##[6] T. Sicong, X. Jian-Xin, and S. K. Panda,“Optimization of distribution network incorporating##distributed generators: An integrated approach,” IEEETrans. Power Syst., vol. 28, no. 3, pp. 2421–2432,##Aug. 2013.##[7] W. Su, J. Wang, and J. Roh, “Stochastic energyscheduling in microgrids with intermittent renewable##energy resources,” IEEE Trans. Smart Grid, vol. 5, no.4, pp.1876 - 1883, 2014.##[8] W. Su, J. Wang, K. Zhang, and A. Q. Huang, “Modelpredictive controlbased power dispatch for##distribution system considering plug-in electric vehicleuncertainty,” Electric Power Syst. Res., vol. 106, pp.##29–35, Jan. 2014.##[9] H. S. V. S. Kumar Nunna and S. Doolla, “Multiagentbaseddistributed energy resource management for##intelligent microgrids,” IEEE Trans. Ind. Electron.,vol. 60, no. 4, pp. 1678–1687, Apr. 2013.##[10] M. Fathi and H. Bevrani, “Adaptive energyconsumption scheduling for connected microgrids##under demand uncertainty,” IEEE Trans. Power Del.,vol. 28, no. 3, pp. 1576–1583, Jul. 2013.##[11] M. Fathi and H. Bevrani, “Statistical cooperativepower dispatching in interconnected microgrids,”##IEEE Trans. Sustain. Energy, vol. 4, no. 3, pp. 586–593, Jul. 2013.##[12] Z. Wang, B. Chen, J. Wang, M. M. Begovic and C.Chen "Coordinated energy management of networked##microgrids in distribution systems", IEEE Trans.Smart Grid, vol. 6, no. 1, pp.45 -53, 2015.##[13] N. Nikmehr and S. Najafi Ravadanegh, “OptimalPower Dispatch of Multi-Microgrids at Future Smart##Distribution Grids,” IEEE Trans. Smart Grid, vol. 6,no. 4, pp. 1648 - 1657, July 2015.##[14] Z. Bie, P. Zhang , G. Li , B. Hua , M. Meehan and X.Wang, “Reliability evaluation of active distribution##systems including microgrids,” IEEE Trans. PowerSyst., vol. 27, no. 4, pp.2342 -2350, 2012.##[15] J.A. Martinez-Velasco, G. Guerra, "Parallel MonteCarlo approach for distribution reliability assessment,"##IET Gener. Transm. Distrib., vol. 8, no. 11, pp. 1810–1819, 2014.##[16] Y.R. Rubinstein, D.P. Kroese. Simulation and theMonte Carlo method. 2nd ed. John Wiley & Sons##Ltd.; 2008.##[17]T.Zhou, and W. Sun, “Optimization of Battery–Supercapacitor Hybrid Energy Storage Station in##Wind/Solar Generation System,” IEEE Trans onSustainable Energy, 2014, vol. 5, no. 2, pp. 408-415,##Apr. 2014. ##[18] R. P. Mukund, Wind and Solar Power Systems. Boca Raton, FL, USA: CRC, 1999.##[19] N. Nikmehr and S. Najafi Ravadanegh, " Heuristic probabilistic power flow algorithm for microgrids operation and planning," IET Generation, Transmission & Distribution, Vol. 9, No. 11, pp. 985- 995, 2015.##[20] S.Wang, Z. Li, L.Wu, M. Shahidehpour, and Z. Li, “New metrics for assessing the reliability and economics of microgrids in distribution system,” IEEE Trans. Power Syst., vol. 28, no. 3, pp. 2852–2861, Aug. 2013.##[21] N. Nikmehr and S. Najafi Ravadanegh, "Optimal operation of distributed generations in micro-grids under uncertainties in load and renewable power generation using heuristic algorithm," IET Renewable Power Generation, DOI: 10.1049/iet-rpg.2014.0357, 2015.##[22] Y. M. Atwa and E. F. El-Saadany "Reliability evaluation for distribution system with renewable distributed generation during islanded mode of operation", IEEE Trans. Power Syst., vol. 24, no. 2, pp.572 -581, 2009.##[23] R. Yokoyama, T. Niimura, and N. Saito, “Modeling and evaluation of supply reliability of microgrids including PV and wind power,” in IEEE. Proc. Power and Energy Society General Meeting - Conversion and Delivery of Electrical Energy in the 21st Century, 2008, pp. 1-5.##[24] H. Wu, X. Liu, and M. Ding, “Dynamic economic dispatch of a microgrid: Mathematical models and solution algorithm,” Int J Electr Power Energy Syst, vol. 63, pp. 336-346, 2014.##[25] J. Kennedy, R. Eberhart, "Particle swarm optimization," in Proc. 1995 The International Conference on Neural Networks, pp. 1942-1948##]
Time-Mode Signal Quantization for Use in Sigma-Delta Modulators
Time-Mode Signal Quantization for Use in Sigma-Delta Modulators
2
2
The rapid scaling in modern CMOS technology has motivated the researchers to design new analog-to-digital converter (ADC) architectures that can properly work in lower supply voltage. An exchanging the data quantization procedure from the amplitude to the time domain, can be a promising alternative well adapt with the technology scaling. This paper is going to review the recent development in time-based noise-shaping ADCs, so-called as time-based sigma-delta modulators. Two of the most important architectures named as voltage-controlled oscillator (VCO) -based and time-to-digital (TDC) -based sigma-delta modulators (SDMs) are selected to be reviewed in this paper. The intrinsic advantages and limitations of the these structures are briefly explored. To confirm the effectiveness of the time-mode sigma-delta modulators, a TDC-based continuous-time sigma-delta modulator is proposed as an example and the related simulation results performed in MATLAB are illustrated. The simulation results show that the proposed modulator achieves a dynamic range of 67 dB over 30 MHz with the loop filter of order 2. The proposed TDC-based sigma-delta modulator shows the superiority of the time quantization approach in designing the wideband and less complex continuous-time SDMs.
1
The rapid scaling in modern CMOS technology has motivated the researchers to design new analog-to-digital converter (ADC) architectures that can properly work in lower supply voltage. An exchanging the data quantization procedure from the amplitude to the time domain, can be a promising alternative well adapt with the technology scaling. This paper is going to review the recent development in time-based noise-shaping ADCs, so-called as time-based sigma-delta modulators. Two of the most important architectures named as voltage-controlled oscillator (VCO) -based and time-to-digital (TDC) -based sigma-delta modulators (SDMs) are selected to be reviewed in this paper. The intrinsic advantages and limitations of the these structures are briefly explored. To confirm the effectiveness of the time-mode sigma-delta modulators, a TDC-based continuous-time sigma-delta modulator is proposed as an example and the related simulation results performed in MATLAB are illustrated. The simulation results show that the proposed modulator achieves a dynamic range of 67 dB over 30 MHz with the loop filter of order 2. The proposed TDC-based sigma-delta modulator shows the superiority of the time quantization approach in designing the wideband and less complex continuous-time SDMs.
53
61
Mohsen
Tamaddon
Mohsen
Tamaddon
Ph.D. Student, Integrated Circuits Design Laboratory, Department of Electrical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
Ph.D. Student, Integrated Circuits Design
Iran
m.tamaddon@aut.ac.ir
Mohammad
Yavari
Mohammad
Yavari
Associate Professor, Ph.D. Student, Integrated Circuits Design Laboratory, Department of Electrical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
Associate Professor, Ph.D. Student, Integrated
Iran
myavari@aut.ac.ir
Sigma-delta modulator
TDC
Time-based circuits
VCO
[[1] T. Christopher, Analog-to-Digital conversion via time-mode signal processing, Ph.D. Dissertation, Dept of Electrical and Computer Engineering, McGill University, Montreal, 2007.##[2] Y. Fei, “Design techniques for time-mode noise-shaping analog-to-digital converters: a state-of-the-art review,” Analog Integrated Circuits and Signal Processing, vol. 79. pp 191–206, Nov. 2014.##[3] S. Norsworthy, R. Schreier, and G. Temes, Delta-Sigma Data Converters: Theory, Design and Simulation. New York: IEEE Press, 1997.##[4] J. M. de la Rosa et al., “Sigma-Delta Modulators: Tutorial Overview, Design Guide, and State-of-the-Art Survey,” ,” IEEE Trans. Circuits Syst. I, Reg. Papers, vol. 58, no. 1, pp. 1–21, Jan. 2011.##[5] M. Z. Straayer and M. H. Perrott, “A 12-bit, 10-MHz bandwidth, continuous- time ΔΣ ADC with a 5-bit, 950-MS/s VCO-based quantizer,” IEEE J. Solid-State Circuits, vol. 43, no. 4, pp. 805– 814, Apr. 2008.##[6] B. D. Vuyst, and P. Rombouts, “A 5-MHz 11-bit self oscillating ΣΔ modulator with a delay-based phase shifter in 0.025 mm2,” IEEE J. of Solid-State Circuits, vol. 46, no. 8, pp. 1919–1927, Aug. 2011.##[7] A. Iwata, “The architecture of delta sigma analog-to-digital converters using a VCO as a multi-bit quantizer,” IEEE Trans. Circuits and Systems-II: Exp. Briefs, vol. 46, no. 8, pp. 941 –945, Aug. 1999.##[8] B. Drost et al., “Analog Filter Design Using Ring Oscillator Integrators,” IEEE J. Solid-State Circuits, vol. 47, no. 12, pp. 3120–3129 Oct. 2012.##[9] J. Kim, T. K. Jang, Y. G. Yoon, and S. Cho, “Analysis and design of voltage-controlled oscillator based analog-to-digital converter,” IEEE Trans. Circuits Syst. I, Reg. Papers, vol. 57, no. 1, pp. 18–30, Jan. 2010.##[10] M. Park, and M. H. Perrott, “A 78 dB SNDR 87 mW 20 MHz bandwidth continuous-time ΣΔ ADC with VCO-based integrator and quantizer implemented in 0.13 m CMOS,” IEEE J. Solid-State Circuits, vol. 44, no. 12, pp. 3344–3358, Dec. 2009.##[11] K. Reddy, S. Rao, R. Inti, B. Young, A. Elshazly, M. Talegaonkar, and P. Hanumolu, “A 16-mw 78-dB SNDR 10-MHz BW CT DR ADC using residue-canceling VCO-based quantizer.” IEEE J. Solid-State Circuits, vol. 47, no. 12, pp 1–12, Dec. 2012.##[12] G. Taylor and I. Galton, “A mostly digital variable-rate continuous-time ADC ΔΣ modulator,” in Proc. IEEE ISSCC, pp. 298–299, Feb. 2010.##[13] S. Rao, B. Young, A. Elshazly, W. Yin, N. Sasidhar, and P. Hanumolu, “ A 71 dB SFDR open loop VCO-based ADC using 2-level PWM modulation,” in Proc. IEEE Symp. VLSI Circuits Digest of Technical Papers, pp. 270-271, Jun. 2011.##[14] S. Zaliasl et al., “A 12.5-bit 4MHz 13.8mW MASH ΣΔ modulator with multirated VCO-based ADC,” IEEE Trans. Circuits Syst. I, Reg. Papers, vol. 59, no. 8, pp. 1604–1613, Aug. 2012.##[15] G.W. Roberts, and M. Ali-Bakhshian, “A Brief Introduction to Time-to-Digital and Digital-to-Time Converters,” IEEE Trans. Circuits and Systems-II: Exp. Briefs, vol.57, no.3, pp.153-157, March 2010.##[16] D. I. Porat, “Review of sub-nanosecond time-interval measurements,” Nuclear Science, IEEE Transactions, vol 20, no .5, pp.36-51 , October. 1973.##[17] V. Dhanasekaran et al., “ A Continuous-Time Multi-Bit ΔΣ ADC Using Time Domain Quantizer and Feedback Element,” IEEE J. Solid-State Circuits, vol. 46, no. 3, pp. 639-650, March 2011. ##[18] L. Hernandez, and E. Prefasi, “Analog to digital conversion using noise shaping and time encoding,” IEEE Trans. Circuits Syst. I, Reg. Papers, vol. 55, no. 8, pp. 2026–2037, Aug. 2008.##[19] E. Prefasi, L. Hernandez, S. Paton, A. Wiesbauer, R. Gaggl, and E. Pun, “A 0.1 mm , wide bandwidth continuous-time sigma delta ADC based on a time encoding quantizer in 0.13 um CMOS,” IEEE J. Solid-State Circuits, vol. 44, no. 10, pp. 2745–2754, Oct. 2009.##[20] C. Taillefer, and G. Roberts, “Delta-sigma A/D converter via time-mode signal processing,” IEEE Trans. Circuits Syst. I, Reg. Papers, vol. 56, no. 9, pp. 1908–1920, Sept. 2009.##[21] M. Straayer, M.H. Perrott, “A 10-bit 20 MHz 38 mW 950 MHz CTRDADC with a 5-bit noise-shaping VCO-based quantizer and DEM circuit in 0.13μm CMOS.” in Proc. IEEE Symp. VLSI Circuits Digest of Technical Papers, pp. 246–247, Jun. 2007.##[22] M. Park, and M. H. Perrott, “A single-slope 80 Ms/s ADC using two-step time-to-digital conversion.” in Proc. IEEE Symp. Circuits and Systems, pp. 1125–1128, May. 2009.##[23] S. Zaliasl et al., “A 77 dB SNDR, 4MHz MASH ΔΣ modulator with a second-stage multi-rate VCO-based quantizer.” in Proc. IEEE Symp. Custom Integrated Circuits Conference (CICC), pp. 1–4, Sept. 2011.##[24] V. Dhanasekaran et al., “A 20 MHz BW 68 dB DR CT ΔΣ ADC based on a multibit time-domain quantizer and feedback element.” in Proc. IEEE Symp. International Solid-State Circuits Conference Digest of Technical Papers (ISSCC), pp. 174–175, Feb. 2009.##[25] P. Gao, X. Xing, J. Cranincks, and G. Gielen, “ Design of an intrinsically linear double-VCO-based ADC with 2nd-order noise shaping.” in Proc. IEEE Symp. Design, Automation & Test in Europe Conference and Exhibition, pp. 1215–1220, Mar. 2012.##[26] T. Jang, J. Kim, Y. Yoon, and S. Cho, “A highly-digital VCO-based analog-to-digital converter using phase interpolator and digital calibration.” IEEE Trans. VLSI Systems, vol. 20, no. 8, pp. 1368–1372, Aug. 2012.##[27] Y. Yoon, S. Park, and S. Cho, “A time-based noise shaping analog-to-digital converter using a gated-ring oscillator.” in Proc. IEEE Symp. MTT-S International Microwave Workshop Intelligent Radio for Future Personal Terminals, pp. 1–4, Aug. 2011.##[28] U. Wismar, D. Wisland, and P. Andreani, “A 0.2V 0.44μW 20KHz Analog to Digital ΣΔ modulator with 57 fJ/conversion FoM.” in Proc. IEEE Symp. European Solid-State Circuits Conference (ESSCIRC) pp. 187–190, Sept. 2006.##[29] Y. Tousi, and E. Afshari, “A miniature 2 mW 4 bit 1.2 GS/s delay-line-based ADC in 65 nm CMOS.” IEEE J. Solid-State Circuits, vol. 46, no. 10, pp. 2312–2325, Oct. 2011.##[30] A. Gelb and W. V. Velde, Multiple-Input Describing Functions and Non-Linear System Design, New York: McGraw-Hill, 1968.##[31] E. Roza, “Analog-to-digital conversion via duty-cycle modulation,” IEEE Trans. Circuits and Systems-II: Exp. Briefs, vol. 44, no. 11, pp. 907–914, Nov. 1997.##[32] M. Tamaddon, and M. Yavari, “An NTF-Enhanced Time-Based Continuous-Time Sigma-Delta Modulator,” Journal of Analog Integrated Circuits and Signal Processing, vol. 85, no. 2, pp. 283-297, Nov. 2015.##[33] M. Tamaddon, and M. Yavari, “A wideband time-based continuous-time sigma-delta modulator with 2nd order noise-coupling based on passive elements,” International Journal of Circuit Theory and Applications, published online, Jun. 2015.##]