S5180B is the first CMT VNA with built-in Pulse Modulation Generation/Measurement capabilities. The Pulse Modulation feature is a paid software option sold separately from the VNA and is only compatible with the S5180B VNA due to hardware requirements. S5180B has a built-in pulse modulator, synchronizer, and a set of logical generators supporting various pulse generation options and corresponding measurement modes. Pulses can be generated Synchronously or Asynchronously with respect to VNA measurement timing.   URL: https://coppermountaintech.com/vna/s5180b-2-port-18-ghz-analyzer/?utm_source=mwj&utm_medium=vendor+view&utm_campaign=website