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
