The Design Of Analog Channel Of Arbitrary Waveform Generator With1GSPS And LXI Bus

In modern electronic measure system, arbitrary waveform generator (AWG) is animportant part of the universal measure instruments. The arbitrary wave generator ismainly composed with the digital synthesis section and the analog channel section, thedigital synthesis section is used to synthesize the signal waveform, while, the analogchannel section process the output signal of the digital section in order to meet with theusing standard.The output signal of the analog channel is the ultimate stage of the AWG.Therefore, the performance of the analog channel will directly affect the AWG.Technical difficulties of the analog channel are the purity of the output signal waveformand the output amplitude range.This thesis focuses on the design of analog channel of the AWG with1GSPS.Because this thesis will process the400MHz high frequency signals. And based on thevarious indicators in the project requirements, the thesis will ensure the flatness of theoutput signal. This thesis mainly covers the following contents:1. This thesis proposed the input circuit design, the filter design and the amplitudecontrol program. The input circuit design in analog channel is used to tackle the affectof the impedance matching by the characteristics of the output signal from the signalsynthesizing board. The filter design can filter out the spurious signals caused byzero-order hold characteristics of DAC. The output signal could have a relatively largeamplitude adjustment range because of the amplitude control program.2. As the limitations of the square wave signal generated by digital way, I designedthe Square wave generator circuit in the analog channel. It can not only produce thehigh-frequency square wave, and also has a larger duty cycle adjustment range.3. Select the associated test equipment to build a test platform, verify the functionaland performance indicators, and analyze the test results. And verify the reasonablenessof the design.Through the tests, the results indicate that the analog channels can be outputmaximum400MHz frequency signal, the signal has a higher flatness index. The adjustable amplitude range of the output signal can meet the requirements of the projectindicators. The output signal has a high purity waveform. The measured output signalindicators also meet the requirements of the indexes. The indexes are leading indomestic.