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.

To provide a better understanding of build-to-print in general and the breadth of our offerings, as well as how our thin-film technology can benefit your applications, we’ve put together a Build-to-Print Basics series. In part 12, we tie everything we’ve discussed so far together and provide more specifics about how we use the processes and options detailed throughout this series to create the custom microwave components you need.

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.

Spectral efficiency, or bandwidth efficiency, tells us about the channel capacity over a 1Hz bandwidth. It is a measure of the efficiency of a physical layer protocol when it comes to utilizing the spectrum available. To understand how spectral efficiency is calculated, it’s first important to understand the Shannon-Hartley Theorem in the context of 5G mmWave applications (which we discussed in an earlier blog post).

Quadrature hybrid couplers are basic building blocks for many RF and microwave systems. For these couplers, the input splits into two output signals, of equal magnitude, with a 90 degree phase difference. Quadrature hybrid couplers provide improved input match for unbalanced loads. Energy splits evenly between outputs, and some energy is reflected back due to mismatch. For example, in Figure 1, there is a 90 degree phase difference between the two outputs, so the energy reflected at point A is 180 degree out of phase and cancels at the input port. At point B, the energy is in phase and sums at the isolated port, which is terminated.

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.

Looking back, 2020 was a year full of big changes regarding how RF spectrum is allocated in the US. Led by the Federal Communications Commission (FCC), multiple portions of the spectrum ranging from the C band to the V band were either opened to new uses and/or auctioned to new users throughout the year. These changes are driving a variety of new opportunities for wireless device manufacturers and broadband and cellular carriers, which is resulting in a range of exciting new challenges for RF technology vendors to help solve. 

One of the things all technical disciplines excel at is creating terminology that can trip up those who are not accustomed to speaking the language every day. Take the title of this article for example. These three words sound similar and are definitely inter-related, but they are not inter-changeable.