Spread spectrum clocking [SSM] (Part 2)

In this Video we show the impact of various modulation shapes on the frequency spectrum of a spread spectrum modulated carrier signal and briefly compare their performance. Tutor: Nikolaus Juch Contents: 0:00 Configuration 0:56 Square modulation 1:30 Sinusoidal modulation 1:43 Triangular modulation 1:56 Upramp modulation 2:10 Downramp modulation Equipment used: Rohde&Schwarz FSV Signal analyzer + DC block Settings: Center Frequency = 2.5 MHz Frequency span = 4 MHz RBW = 20 kHz Ref. level = 90 dBµV Rigol DG1022 Arbitary waveform Generator Settings: Waveform = Sine Frequency = 2.5 MHz Amplitude = 100 mVrms FM – Settings: deviation = 500 kHz Modulation Frequency = 20 kHz Modulation shapes: rectangular, sinusoidal, triangular, up- and down ramp