Design Of Hign Capability LXI Signal Generator

Signal generator is the basis for automatic testing. Its functions determine the diversity of the tasks of testing and its capability affects the precision of test results. Arbitrary waveform and pulse generating technology is studied in this thesis, and a high capability signal generator is designed, which is based on LXI bus and is composed of an arbitrary waveform generator and a nanosecond pulse generator. This signal generator meets the LXI C Class equipment specifications, and it can meet the needs of testing tasks of scientific research and industrial. This design is of great significance to construct LXI Automatic Testing System for China.The arbitrary waveform generator of this signal generator is based on Direct Digital Synthesis (short for DDS), which is carried out in FPGA by Verilog HDL hardware description language. There is very high performance of frequency resolution by using 48-bit phase accumulator. The pulse generator is designed by using high bandwidth transistors as ultra-fast switches and by the process of charging and discharging of capacitor and by the Step Recovery Diode step effect. The voltage of negative pulse can exceed 8 Volts and the pulse duration can shorter than 2 ns. This signal generator is controlled by a circuit board, also called for Kernel Board, which is integrated by ARM microprocessor. Thanks to the facility of LXI equipment, this design is debugged and developed only by serial port and LAN port.There is a software system meeting LXI specifications, by which the equipment can be controlled by two ways. One way is using web browser based on WEB interface and web can communicate with server (Kernel Board) by CGI programs. Control panel by MFC and IVI-COM drivers are designed for the equipment. Users only need a cable to control the equipment completely on any computer after installing software packages provided above.Finally, this thesis tests outputs of the equipment, and analyzes error of frequency and voltage. And for more, there is In-depth analysis for testing results of pulse generator. Testing results show that the design in this thesis meets all requirements.