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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© 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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