The Study Of Intelligent Three-Channel Phase Hunting Arbitrary Waveform Generator

AWG (Arbitrary Waveform Generator) is a commonly used singal source, and one of the most widely used equipment in the field of modern electronics testing. Because it can generate wave signals, including the ideal and non-ideal ones, it is widely used in communications, radar, navigation, aerospace and other fields. In addition to pure sine wave, square, triangular wave, and other conventional wave, AWG can also produce a linear FM, PM, AM signal and program-controlled low-duty cycle square signal, and also generate arbitrary Waveform and noise signal according to the user's testing demand. AWG's flexiable output signal make it as an integral part of the comprehensive testing system.What this thesis concentrates on is a new-style of AWG that based on Direct Digital Synthesis (DDS) technique which came into being in the 1970s. DDS is an advanced technology on frequency synthesis and its primary advantages lie in controlling facility, continuous phase and fine uturefrequency resolution. It is an important field of the AWG design. This thesis has introduced in detail the composition, working principles and the properties of DDS, telling the designing process of signal generators, anglicizing the reason of DDS phase noise and giving the method of reducing the noise.Realization of DDS depends on the digital devicesof high speed and high performance and AD9854 which is specialized for DDS. In this paper, the system based on C8051F120 is selected to realize DDS. Its high-speed, low-power, multifunctional, cost effective is particularly suitable for the central controller chip of instruments. AD9854 is cheap, steady, swift and is suitable to be used as signal generators.This paper attempts to use the advanced embedded system and give a further research on how to design the AWG based on C8051F120 embedded system and DDS technique from the view of project application. The author has researched and developed an AWG with the technique of DDS. The system framework, circuit framework, designing method, detailed software flow chart and program of arbitrary waveform editor are given in this paper. The result of experimentation proves that this AWG has attained the desire of design.Finally, the main research contents of full text are summarized, main research conclusions and innovation points are given, and the insufficiency of this paper and research emphases in the future are pointed out.