Mathematical modelling and research of output spectrum of synthesizers based on high-speed DAC for 5G

Abstract

Abstract The paper presents a mathematical model of the output signal of high-speed digital-to-analogue converters in special operating modes. This model simulates the output signal of a high-speed digital-to-analogue converters in time and frequency domain for the research of their frequency spectrum. The model consists of nonlinearities which cause undesirable frequency components (spurs) in the output spectrum. These are nonlinearities due to output signal sampling, phase code truncation and amplitude quantization errors. The paper describes PLL+DAC synthesizer which allows reducing the number and level of spurs in output spectrum.