Software invades hardware in new test equipment

SOME call it software-based instrumentation or virtual instrumentation, but whatever the terminology, it's a way to perform measurements on complex microwave and communications systems faster, more efficiently, and with greater precision and accuracy. Manufacturers of test equipment are loading more code into their instruments since the types and numbers of measurements necessary to verify the proper operation of wireless communications products are too difficult as well as time consuming for the traditional dial twisting and button punching of human beings. But it's not simply a matter of writing programs to make test instrument measurements simpler and more automatic. Equipment operating at microwave frequencies runs at signal levels "down in the mud," and outside disturbances such as noise can impose significant problems on measurement accuracy and reproducibility when the test equipment is connected to a bus and controlled by a personal computer (PC). As a result, bus-based software instrumentation is not get universal at microwave frequencies since some types of measurements must still be carried out the old-fashioned way.