2
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Analog Carriers and Modulation
1 Basic Sine Wave Amplitude Modulation (AM) . . . . . . . . . . . . . . .3
2AM with Adjacent Carriers . . . . . . . . . . . . . . . . . . . . . . . . . .5
3Multi-Tone Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
4Frequency Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
5FM with Dual-Tone Modulation . . . . . . . . . . . . . . . . . . . . . . . .10
6 FM Stereo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
7 Adding Noise to a Carrier Signal — AWG Noise Characteristics . . . . . . . . . . .14
Digital Modulation
8 Digital Phase Modulation — PSK . . . . . . . . . . . . . . . . . . . . . . .17
9 Baseband Digital Patterns . . . . . . . . . . . . . . . . . . . . . . . . . .19
10 Digital AM — OOK and BPSK . . . . . . . . . . . . . . . . . . . . . . . . .20
11 Digital FM — FSK . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
12 Quadrature Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . .23
13 Filtering Out Unwanted Sidebands . . . . . . . . . . . . . . . . . . . . . . .25
14 Direct Sequence Spread Spectrum . . . . . . . . . . . . . . . . . . . . . .28
For More Information on Tektronix Instrumentation . . . . . . . . . . . . . . . . . .29
AWG2000 Series Arbitrar y Waveform Generators . . . . . . . . . . . . . . . .30
TDS 744A Digitizing Oscilloscope . . . . . . . . . . . . . . . . . . . . . . .31
Table of Contents
Note: Each signal and waveform screen in this application note originates from one of three types of instruments: an
arbitrary waveform generator, a digital storage oscilloscope, or a spectrum analyzer. Each illustration is annotated
with a symbol indicating its origin:
AWG
Oscilloscope (DSO)
Spectrum Analyzer