Many critical military operations around the world are increasingly relying on a variety of electronic warfare devices for a range of threat suppression, detection, and neutralization activities. This means that numerous devices operating across the RF spectrum including low-frequency devices in the VHF band and mmWave devices in the Ka band are necessary. As shown in Figure 1, when many electronic warfare devices are in use, a large number of signals are being sent and received and crossing paths. Therefore, it’s easy for any one of these devices to experience issues with interference if proper filtering techniques are not in place.

In part one of our two-part RF filter trends series, we discussed several emerging trends effecting the “jobs” RF filters need to perform. In this second part, we expand on these trends by digging into more of the technical trends and providing an overview of the filtering solutions that can help RF filter designers stay on top of those trends.

As an RF engineer, whether you are building a 5G antenna to mount on top of a street light or a satellite that will be launched into space, you are likely being asked to reduce three key factors – size, weight, and power (SWaP). The need to reduce SWaP is becoming increasingly common, but also increasingly tricky, because even though wavelength and the corresponding critical dimensions decrease as frequency goes up, RF circuits generally scale in size and complexity with the wavelengths supported. Thus, it can be really difficult to find companies who are up for the challenge of providing components that are designed to help reduce SWaP

To ensure Knowles Precision Devices (KPD) customers achieve optimal performance and are successful with our products, we have compiled a number of techniques to mitigate PCB variation and reduce the unwanted effects of microstrip technology (e.g. cross talk and radiation).