Innovating essential high technology systems with demanding specifications is always challenging; making any sort of difference requires extensive resources and deep subject matter knowledge.

But that’s what keeps it interesting.

RF circuits for applications in the mmWave range (30 to 300 GHz) require high-performance filtering to meet the high-data, high-speed functionality that operating at these higher frequencies promises. However, filters for devices operating in the mmWave range will not function optimally if your printed circuit board (PCB) is not configured appropriately. For this reason, RF design engineers need to make a number of critical PCB design decisions that range from selecting the right materials to developing a board configuration that will limit common issues such as spurious-wave-mode propagation, conductor and radiation losses, unwanted resonance, and dispersion.

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).

The millimeter wave (mmWave) part of the electromagnetic spectrum is at the high end of the microwave region, which spans ~300 MHz to 300 GHz, and is usually taken to mean frequencies from ~30 GHz to 300 GHz and wavelengths in the range of 1mm to 1cm (Table 1). This dramatically increases available bandwidth, thus expanding achievable data rates, which makes these frequencies extremely interesting to teams around the world working on fifth generation (5G) communications.

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.

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. 

As radio architectures evolve, the need for filters is also evolving. At the same time, the industry is working to miniaturizes mmWave devices while continually minimizing costs. This means RF designers need filter solutions that offer a smaller footprint while keeping prices manageable.

Planning is in the works for Fifth Generation (5G) communication systems that will enable a hundred-fold increase in user data-rates – and with this increase comes a need for significant increases in bandwidth over what is currently available. Why does bandwidth follow when we ask for an increase in data rates? 

As 5G innovation forges on, radio systems continue to emerge. Each system has a range of requirements, including specific RF filter performance needs, and it’s up to the 5G FR2 Ecosystem of suppliers to meet that demand. In response, Knowles Precision Devices (KPD) supports a wide variety of 5G radio applications.

At Knowles Precision Devices, we support a wide variety of industries and applications with unique needs; the product catalog is constantly evolving to accommodate. We are often asked which frequencies we support. While our microwave products excel at higher frequencies, the catalog spans a wide range.