Complex systems require complex test solutions. That simple statement summarizes the measurement needs for a slew of emerging wireless communications standards, such as WiMAX and Long Term Evolution (LTE) systems. Such systems rely on complex digital modulation schemes, multicarrier configurations, and multiple-input, multiple-output (MIMO) antenna and channel architectures. Because of the diversity of signal formats, no traditional signal generator or signal analyzer can meet the measurement requirements for these emerging wireless standards.
Rather than try to design an instrument that can meet all current requirements, many test-equipment manufacturers are adopting a software-defined-radio (SDR) approach that allows present and future test needs to be met by the use of digital hardware and software programmability. The approach has worked wonders for military users, who must communicate among scores of different radio platforms via the programmability of SDR tactical radios. As evidenced by the Aeroflex 7000 series test solution below, and by many previous SDR-based test instruments from other manufacturers, the days of traditional "fixed-function" test gear may be passing.