An All Digital Qam Modulator with Radio Frequency Output
نویسندگان
چکیده
A software defined radio (SDR) terminal promotes programmable realizations of the physical layer functionalities. A lot of research work has been done in applying digital signal processors (DSP) and field programmable gate arrays (FPGA) to implement the baseband functionalities of the physical layer. In this paper, the programmable solutions are extended to the radio frequency (RF) band for the transmitter. Digital pulse width modulation (PWM) technique is used to generate binary signals at radio frequency. A QAM modulator, combined with PWM, is implemented using off the shelf FPGA. The output of this all digital transmitter has a center frequency of 800 MHz.
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