MICROWAVE MODULAR INSTRUMENT PACKAGE

AUTOMATIC TEST EQUIPMENT (ATE) FOR RADIO FREQUENCY AND MICROWAVE APPLICATIONS TYPICALLY EMPLOY CONVENTIONAL "RACK-AND-STACK" IEEE-488 INSTRUMENTS TO PROVIDE STIMULUS AND MEASUREMENT FUNCTIONS. EACH INSTRUMENT IS A STAND-ALONE TEST FUNCTION AND USUALLY CONTAINS IT'S OWN DEDICATED MICROPROCESSOR, POWER SUPPLY, CHASSIS, FRONT PANEL, AND EXTERNAL COMMUNICATIONS INTERFACE. IN ATE SYSTEM APPLICATIONS, CONSIDERABLE HARDWARE REDUNDANCY RESULTS, SINCE THESE CIRCUIT ELEMENTS ARE DUPLICATED IN EACH INSTRUMENT. SOFTWARE REDUNDANCY ALSO EXISTS, AS SEPARATE SOFTWARE MODULES ARE NEEDED FOR THE SYSTEM COMPUTER TO COMMUNICATE WITH EACH INSTRUMENT. RECENT PROGRESS HAS BEEN MADE IN THE DESIGN OF MODULAR INSTRUMENT SYSTEMS WHICH PROVIDE A COMMON CHASSIS, MICROPROCESSOR, POWER SUPPLY, AND COMMUNICATIONS INTERFACE TO HOST A NUMBER OF MODULAR INSTRUMENT PLUG-INS. THIS CONCEPT REDUCES HARDWARE/SOFTWARE REDUNDANCY, BUT TO-DATE, HAS BEEN APPLIED ONLY TO LOW-FREQUENCY ANALOG (UNDER 100 MHZ) INSTRUMENTS. IT IS PROPOSED TO INVESTIGATE THE FEASIBILITY OF EXTENDING THE MODULAR INSTRUMENT CONCEPT TO HIGHER FREQUENCY INSTRUMENTS, PARTICULARLY INTO THE MICROWAVE REGION (UP TO 40 GHZ).