Design And Implementation Of Software System In USB Vector Network Analyzer

The Vector Network Analyzer(VNA)is an instrument that measures the network characteristics of the device under test;it has been widely used in national defense and commercial area for its high measurement accuracy and advanced testing capabilities.With the rapid development of Internet of Things(IoT),the test for communication cables,signal receive and transmit components is more urgent now,this also brings a great challenge for testing equipment.A compacted,portable,easy to connect vector network analyzer will take a great role in manufacturing and engineering measurement.Flexible and small packed instrument will become the new development trend with the increasing integrated degree of electronic circuits.A USB Vector Network Analyzer(VNA)is small size equipment that can be connected through USB interface to any standard windows PC device,then the PC device and the connected VNA module work together as a traditional vector network analyzer.Software requirements are the most important part in software engineering,the paper first take focus on the function requirements,specification requirements and interface requirements of the USB VNA according to current VNAs.A brief introduction of the overall system design of the USB VNA system is represented then,focusing on the selection of USB interface chip,the RF generator and receiver scheme.After that is the detailed description of the communication scheme between the host PC,the interface & DSP unit and the RF & receiver unit.Software test method is prompt in the end to verify the rightness of the entire system,testing result and test cases are also presented.