Extraction of Optimum PWM Levels in LORAN Switching Transmitter for Ground-Based Positioning System

Document Type : Original Article

Authors

1 Malek Ashtar University of Technology

2 emam hossein university

3 Imam Hossein University

Abstract

Long-Range-Navigation (LORAN) pulse generator is an essential part of ground-based Local Positioning System (LPS) that provide a specific standard waveform. There are several solutions for design and implementation of the pulse generator. Switching amplifiers using Pulse-Width-Modulation (PWM) technique is one of the solutions that can be used for this purpose. In this paper, the simple PWMwas modified to a multi-level PWM and its optimum levels are extracted to provide a high power LORAN transmitter.  Multi-level PWM provides essential standards of LORAN pulse waveform. In order to provide a transmitter with 1MW power, three- to- eleven levels of PWM using 16 Class D amplifiers has been considered. At constant conditions, such as power and number of amplifier modules, the requirements and specifications of transmitter have been simulated. Simulation results show that in the best case, using eleven levels for PWM,the maximum zero crossing error in the 4th to 12th half-cycle is 16.6 ns and the bandwidth of provided pulse is 5 kHz. Moreover, MMSE and maximum error of peak points in the first eight half-cycles are 0.009 and 0.021 respectively, which are appropriate standards of a LORAN transmitter.

Keywords

Main Subjects


[1]     Nunes, F. D.; Sousa, F. M. G. “GNSS Blind Interference Detection Based on Fourth-Order Autocumulants”; IEEE Trans. Aerosp. Electron. Syst. 2016, 52, 2547-2586.##
[2]     Wildemeersch, M.; Slump, C. H.; Rabbachin, A. “Acquisition of GNSS Signals in Urban Interference Environment”; IEEE Trans. Aerosp. Electron. Syst. 2014, 50, 1078-1091.##
[3]     Axelle, E.; Eklof, F. M.; Johansson, P.; Alexandersson, M.; Akos, D. M. “Jamming Detection in GNSS Receivers: Performance Evaluation of Field Trials”; Navigation 2015, 62, 73-82.##
[4]     Motella, B.; Presti, L. L. “Methods of Goodness of Fit for GNSS Interference Detection”; IEEE Trans. Aerosp. Electron. Syst. 2104, 50, 1690-1700.##
[5]     Abdizadeh, M.; Curran, J. T.; Lachapelle, G. “New Decision for GNSS Acquisition in the Presence of CW Interference”; IEEE Trans. Aerosp. Electron. Syst. 2014, 50, 2794-2806.##
[6]     Johnson, G.; Shalaev, R.; Hartnett, R., Swaszek, P.; Narins, M. “Can Loran Meet GPS Backup Requirements?”; IEEE Trans. Aerosp. Electron. Syst. 2005, 20, 3-12.##
[7]     Johnson, G. W.; Swaszek, P. F.; Hartnett, R. J.; Shalaev, R.; Wiggins, M. “An Evaluation of eLoran as a Backup to GPS”; IEEE Conf. Technologies for Homeland Security 2007, 95-100.##
[8]     Lili, Z.; Xi, X.; Zhang, J.; Pu, Y. “A New Method for Loran-C ASF Calculation over Irregular Terrain”; IEEE Trans. Aerosp. Electron. Syst. 2013, 49, 1738-1744.##
[9]     Bayat, M.; Madani, M. H. “Analysis and Simulation of a Hybrid Filter to Cancel Cross Rate Interference in Loran System”; Advanced Defence Sci. & Technol. 2017, 4, 51-60.##
[10]     Helwig, A.; Offermans, G.; Stout, C.; Schue, C. “Next Generation Low Frequency Solutions for Alternative
Positioning, Navigation, Timing, and Data(PNT&D) Services and Associated Receiver Technology”; Proc. Int.
Meeting, ION 2012, 1221–1232.##
[11]     Zhou, L. L.; Xi, X. L.; Liu, J. F.; Yu, N. M. “LF Ground Wave Propagation Over Irregular Terrain”; IEEE Trans. Antennas Propag. 2011, 59, 1254–1260.##
[12]     Tim, H. “Next Generation LF Transmitter for (e)Loran Systems”; Nautel  Limited. 2008.##
[13]     Inside GNSS "UrsaNav to Buy Megapulse Assets Including Loran-C and GPS Backup Candidate eLoran"; http://insidegnss.com/ursanav-to-buy-megapulse-assets-including-loran-c-and-gps-backup-candidate-eloran, 2013.##
[14]     Fox, J. E. “Performance Study of the Loran-C System in the Presence of Wideband Interference”; Master's Thesis, University of Tennessee, Knoxville, 2006.##
[15]     Ecker, W. “Loran-C User Handbook”; Technical Report, Office of Navigation Safety and Waterway Services, 2006.##
[16]     Khorrami, A.; Afifi, A.; Amiri, P.; Aghazade, T. “Design and Fabrication of a Loran Pulse Based on PWM Method for LPS Navigation System”; Radar 2014, 2, 51-58.##
[17]     Wei, X.; Yan, L.; Qing, L. “Loran-C Synchronous Interference Suppression Using Improved Adaptive
Algorithms”; IEEE Trans. Audio, Speech, Language Process. 2007, 57, 47-49.##
[18]     Yinbing, Z.; Xu, J.; Qiu, T.; Cui, G. “Synchronous Carrier Wave Interference Suppression Based on Accumulation and Average in Loran-C”; Ninth IEEE Int. Conf. on Electronic Measurement & Instruments, 2009.##
[19]  Xiaoli, Xi; Zhou, L.; Zhang, J.; Liu, J.; Wang, L. “Combined IE-FDTD Algorithm for Long-Range Loran-C Ground-Wave Propagation”; IEEE Trans. Antennas Propag. 2012, 60, 3802-3808.##
[20]  Liatos, P.; Hussein, A. M. “Characterization of 100-kHz Noise in the Lightning Current Derivative Signals Measured at the CN Tower”; IEEE Trans. Electromagn. Compat. 2005, 47, 986-997.##
[21]  Dean, C. B. “Automatic Pulse Sharping with the AN/FPN-42 and AN/FPN-44A Loran-C Transmitters”; Master's Thesis, Naval Postgraduate School, 1992.##
[22]  Bayat, M.; Madani, M. H. “Loran Phase Code Revisited for Continuous Wave Interference Cancellation”; IET Sci. Measurement & Tech. 2017, 11, 322-330.##
[23]  Arthur, H.; Gerard, O.; Chris, S.; Charles, S. “Design and Performance of a Low Frequency Time and Frequency Dissemination Service”; Proc. Int. Meeting, FAA APNT
Public 2013, 75-84.##
[24]  Helwig, A.; Offermans, G.; Schue, C. “Low Frequency (LF) Solutions for Alternative Positioning, Navigation, Timing and Data (APNT&D) and Associated Receiver Technology”; Proc. Int. Meeting, ION 2011, 166- 183.##
[25]  Narins, M. “Alternative Positioning, Navigation, and Timing Initiative Assumptions and Requirements”; Proc. Int. Meeting, FAA APNT Public 2010, 41-49.##
[26]  Tu, Y. J.; Jong, T. L.; Liaw, C. M. “Development of a Class-D Audio Amplifier with Switch Mode Rectifier Front-end and its Waveform Control”; IET Power Electronics 2011, 4, 1002-1014.##
Volume 10, Issue 4 - Serial Number 38
September 2020
Pages 351-360
  • Receive Date: 06 November 2018
  • Revise Date: 08 December 2018
  • Accept Date: 08 January 2019
  • Publish Date: 21 January 2020