Today’s 4G wireless communication systems with carrier aggregation are predominantly using LTE signals modulated over several bandwidths, typically 5, 10, 15, 20 and 40 MHz. Signals generally span from 700 to 6000 MHz. Filtering is often required to reduce harmonics and improve dynamic range when testing LTE products. To replace the large number of fixed filters usually required, the company has developed and is now shipping a filtering system that can tune a bandpass filter anywhere in the 700 to 6000 MHz range with continuously adjustable bandwidth. The system has software interfaces for automated testing corresponding to the two hardware interfaces (Ethernet and GPIB), as well as a convenient web-based user interface for devices such as smartphone, tablet and traditional computer.