A Virtual Implementation of VSG & VSA

Vector signal generator (VSG) and vector signal analyzer (VSA) are instruments widely used for the measurement of digital communication systems. In this project a virtual VSG and a virtual VSA have been developed by using the graphical programming language LabVIEW. The analogue electrical interface of the instruments is implemented by using National Instrument Data Acquisition Unit (DAQ). The virtual VSG can generate modulated vector signals based on various digital modulation formats, change the signal bandwidth to pre-allocated spectrum, and transmit the modulated signal through analog channel. The generated vector signals can be analyzed by the VSA, which integrates the functions of digital demodulator, oscilloscope, spectrum analyzer, constellation diagram analyzer, and bit error rate tester (BERT). It can measure the data from analog channel, recover the original message signal from modulated signal, display the constellation diagram, calculate the bit error rate, etc. Finally, a general analysis of bit error probability is present via statistical simulation.