Hi XFSong,
it is possible to control your Agilent 33220 over GPIB, USB or Ethernet. For all of them, you can use the VISA-driver-technology to communicate with the instrument from LabVIEW. Please refer to the user manual of your device to learn more about all available functions and commands. There will be a command to get the values from the device and to send the values. It is possible to display them with LabVIEW, if you can get the signals with one of the above mentioned ports.
National Instruments
District Sales Manager