Research On ARM Control Module Of Agile Signal Generator

The rapid development of 5G communications and national defense security has placed higher and higher requirements on the test accuracy,phase noise,and ease of use of the signal generator.In addition,it requires functions such as frequency agility and precise power adjustment.The agile signal generator is not only used in component test,antenna,automatic test system and other fields where frequency switching time has great influence on system test,but also widely used in electronic warfare,agile frequency guidance system,frequency-agile radar and other national defense fields.The main content of this paper is about the design of ARM control module of the agile signal generator.After analyzing the requirements of the agile signal generator,the hardware scheme and software scheme of ARM control module are designed,and the hardware circuit and software function design are realized.The specific research content of this paper is as follows:1)Peripheral function circuit design.With the high performance processor IMX6 Q as the core,the peripheral circuit is built to complete the circuit schematic and layout design.2)Human-computer interaction interface design.Based on the analysis of instrument functions,Qt,a cross-platform tool,is adopted to design the interface structure and menu structure to complete the logical design of human-computer interaction interface,and various parameters can be set in the interface to realize the local control of the instrument.3)Communication design between ARM module and FPGA module of the agile signal generator.The Linux underlying communication driver is designed,and DMA technology is adopted to mount FPGA as sdram-like device on the ARM bus interface,so as to realize the rapid communication between the application program and the underlying hardware.The data structure of the agile control word is designed according to the characteristics of the agile signal generator.The multi-frequency point control word data is edited into a sequence at the ARM end,which is sent and stored in the DDR at the FPGA end.The response to the control word is made in the form of serial playback.The agile efficiency is improved by utilizing the characteristics of FPGA parallel processing.4)Interface design of automatic test system.LXI interface and SCPI command interpreter are used to realize the automatic test system interface.In LXI interface,vxi-11 protocol is mainly used to realize the instrument discovery and recognition mechanism,which can be recognized in the network.Using CGI to achieve Web access interface,the instrument can be accessed through the browser control.According to the characteristics of the instrument,a set of SCPI commands is designed.Aiming at the complex difficulties in the design of the SCPI command interpreter,the search operation time complexity of O(1)hash bucket algorithm is adopted to store the SCPI commands and realize the SCPI command interpreter.Through the above research work,this project has realized the software and hardware contents of the ARM module of the agile signal generator,including the point frequency and sweep frequency output functions realized by ARM and FPGA communication,the instrument program control operation realized by sending SCPI control command through LXI interface,and the access control of the local instrument in the Web browser.