RFSim99
RFSim99 is an S parameter based linear circuit simulator for RF Engineers.
RFSim99 features:
Schematic Editor Front-End
Grid,Smith,Polar & Numerical Output
1 and 2 port S Parameter File Blocks
Stability circles
Tolerance Analysis
Auto-Match (automatic match network generation inc. simultaneous 2 port)
Filter, Attenuator and Match Network Design Assistants
Network Analyzer Direct File Import
RF Calculator
Help and Example Files