During the first-ever virtual Menlo Micro Switch Summit, Knowles Precision Devices joined John Richardson, founder and president of X-Microwave, and Tom Clickenbeard, applications engineer at Menlo Microsystems, to give a presentation on Prototyping Using X-Microwave’s XM-Blocks with Knowles Precision Devices RF Filters and MEMS Switches.

As early adopters of beamforming technology in the 1960s, aerospace and defense organizations have a lot of experience using the initial large-scale active electronically scanned arrays (AESAs) for military radar tracking applications. But these arrays aren’t as convenient for some applications today as the operational frequencies of the targets of interest for many military applications are increasing. This means the wavelengths of the signals that need to be monitored are getting shorter and these radar applications need denser arrays since antenna spacing needs to be set at one half the wavelength. For example, at 25GHz, the wavelength in free space is approximately 12mm (0.47”), leading to half-wave spacing for antennas of 6mm (0.24”). Also, as arrays become denser, the new challenge for RF system designers is avoiding interference in these tighter spaces, especially when transmitting signals.

Today, electronic warfare applications need to detect a wide variety of signals ranging from UHF communications to GPS and other data signals in the L band to high-frequency radar signals that can fall in the X, S, or K bands. Therefore, these receivers need to operate across an extremely wide range of bandwidths to pick up and understand signals anywhere from 300MHz to 20GHz and beyond. However, a basic general wideband antenna isn’t sufficient for these applications because selectivity is needed to determine what you are actually listening to. Additionally, as if the task of designing an ultra-wideband receiver with selectivity wasn’t challenging enough, RF designers are simultaneously facing pressure to reduce the size, weight, and power (SWaP) of these applications as well.

Whether you’re stopping by the International Microwave Symposium (IMS) in person at the Georgia World Congress Center in Atlanta this week, or preparing to attend virtually from June 20 – 25, you can join the team at Knowles Precision Devices for some exciting information and presentations.

Mark your calendars for Thursday, May 13 at 11 AM EDT to join Knowles Precision Devices, Microwave Journal, and RFMW for a live webinar where we will discuss the filtering challenges for digital broadband receivers in electronic warfare applications.

As the RF spectrum becomes more crowded and the number of bandwidth battles grows each year, RF designers are looking for innovative designs that minimize interference while also increasing signal transmission power. Since phased arrays can efficiently maximize gain and signal directivity and minimize interference for both Tx and Rx, adoption of this architecture by RF designers is growing. This means RF designers are also on a quest for phased array filtering options that can help meet the size, weight, and power (SWaP) needs and performance demands required by today’s RF applications. As a result, our engineers have spent a significant amount of time working on an innovative approach that can meet this seemingly impossible combination of requirements.

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

When designing an RF or microwave application, you will always need some level of filtering to attenuate or remove unwanted signals from the desired channel. Since the end goal of what a filter must accomplish is quite broad, it may seem daunting to know what qualities to look for in a filter to get there.