Abstract:

The paper proposes a method of designing a low cost,digital and intelligent frequency tester,with the use of modern digital signal processing and display technology based on Direct Digital Synthesis.The system realizes the frequency and phase measurement of tested network from a range of 20 Hz to 150 MHz,and completes the function of the data storage,-3 dB bandwidth calculation,peak search and so on.The structure achieves a range of precision of 1dBm and phase detection accuracy of 1 degree.

Key words: DSP;DDS;amplitude characteristic measurement;phase characteristic measurement