Field programmable gate arrays (FPGAs) have been used in a wide range of applications including the field of telecommunications. This paper presents the use of FPGAs in the implementation of both analog and digital modulation that includes amplitude modulation, frequency modulation, phase modulation, pulse code modulation, pulse width modulation, pulse position modulation, pulse amplitude modulation, delta modulation, amplitude shift keying, frequency shift keying, phase shift keying, time division multiplexing and different encoding techniques like non-return-to-zero line code, non-return-to-zero mark line code, non-return to zero inversion line code, Unipolar return-to-zero line code, bipolar return-to-zero line code, alternate mark inversion line code, and Manchester line code. Moreover, an FPGA can be designed to emulate a particular device like an oscilloscope, a function generator, or the like. This paper describes the capability of an FPGA to internally generate a low frequency input signal and through the use of a VGA port, it is able to display the signals in an output device. However, the use of FPGAs is not limited to the aforementioned applications because of its reconfigurability and reprogrammability.
Reyes, R., Oppus, C., Monje, J., Patron, N., Guerrero, R., & Fajardo, J. (2008). FPGA Implementation of a Telecommunications Trainer System. International Journal of Circuits, Systems and Signal Processing, 2(1), 87-94.