Abstract
The capability of modern FPGAs has become sufficient to implement complex systems such as a universal receiver with one FPGA. A universal demodulator decodes the three usual modulation algorithms: AM, FM, and PM. This article investigates what types of coherent receivers are suitable for an FPGA implementation. It is shown that both phase-locked loops and Costas loops can be implemented, each with its own advantages. These receivers are used in this article to demodulate WeatherFAX pictures transmitted in central Europe by the low frequency radio stations DCF37 and DCF54 (Carrier 117,4 kHz and 134,2 kHz; Frequency modulation F1C:±150 Hz).
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References
E. Allmann and T. Wolf. Design and Implementation of a Full Digital Zero IF Receiver with FPGA and Floatingpoint DSP. Masterthesis ST 493, Institut für Datentechnik, TH-Darmstadt, 1991.
R. Best. Theorie und Anwendung des Phase-locked Loops. AT Verlag, 1987.
H. Choi. Effect of Gain and Phase Imbalance on the Performance of Lock Detector of Costas Loop. IEEE International Conference on Communications, Seattle, p. 218–222, June 1987.
F. Gardner. Phaselock Techniques. John Wiley, 1979.
H. Geschwinde. Einführung in die PLL-Technik. Vieweg, 1984.
J. Guyot and H. Schmitt. Implementation of a all digital Costas-Loop with FPGA for Coherent Demodulation of Low Frequency Signals. Mastherthesis DT 581, Institut für Datentechnik, TH-Darmstadt, 1993.
J. Holmes. Tracking-Loop Bias Due to Costas Loop Arm Filter Imbalance. IEEE Transactions on Communications, p. 2271–3, Oktober 1982.
W. Lindsey and C. Chie. A Survey of Digital Phase-Locked Loops. Proceedings of the IEEE, p. 410–431, April 1981.
U. Meyer-Bäse et al. Coordinate Rotation DIgital Computer (CORDIC) Synthesis for FPGA. In International Workshop on Field Programmable Logic and Applications, Prag, p. 397–408, September 1994.
U. Meyer-Bäse. The Use of Powerful Algorithms in the Realization of Universal Sampling Receivers in FPGA Technics. Ph.D. thesis, Institut für Datentechnik, TH-Darmstadt, 1995.
U. Meyer-Bäse. A New Class of Forced Response Stable Frequency Sampling Filter for Decimation and Interpolation. IEEE Transactions C&S, December 1995. submitted.
D. McCarty. Digital PLL Suits FPGAs. Elektronic Design, p. 81, March 1992.
A. Makarios and T. Tozer. False-Look Avoidance Scheme for Costas Loops. Electronics Letters, p. 490–2, July 1981.
A. Mararios and T. Tozer. False-Lock Performance Improvement in Costas Loops. IEEE Transactions on Communications, p. 2285–88, October 1982.
R. Resch and P. Schreiner. Implementation of a All-Digital Phase-Locked Loop with Programmable Gate Arrays for Low Frequency FM Demodulation. Masterthesis ST 595, Institut für Datentechnik, TH-Darmstadt, 1993.
R. Sanneman and J. Rowbotham. Unlock Characteristics of the Optimum Type II Phase-Locked Loop. IEEE Transactions on Aerospace and navigational Electronics, p. 15–24, March 1964.
J. Stensby. False Lock in Costas Loops. Proceedings of the 20. Southeastern Symposium on System Theory, p. 75–79, March 1988.
A. Viterbi. Principles of Coherent Communication. McGraw-Hill, 1966.
Xilinx. Databook. XC2000, XC3000, and XC4000, 1993.
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© 1996 Springer-Verlag Berlin Heidelberg
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Meyer-Bäse, U. (1996). Coherent demodulation with FPGAs. In: Hartenstein, R.W., Glesner, M. (eds) Field-Programmable Logic Smart Applications, New Paradigms and Compilers. FPL 1996. Lecture Notes in Computer Science, vol 1142. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-61730-2_17
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DOI: https://doi.org/10.1007/3-540-61730-2_17
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