Eliminating Harmonic content generated in modern RF modules is very important for the overall system performance as well as the end User’s experience. Additional filtering is used in several stages of such Mid/High Band modules used for LTE/5G and other mobile applications. Most of those make use of traditional LC filtering offering rejection level in the order of 10-15dB at a targeted frequency range. Those increase the system losses and result in higher NF and current consumption. An alternative, utilizing BAW resonators forming a Low Pass (LP) can reduce the losses and cost, providing rejections better than 20dB across a very wide range of frequencies. That could improve the on-phone interference between RF systems such as MHB SPADS for LTE, UWB, UHB, Wi-Fi to name a few.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Qorvo US, INC., "Acoustic LP filtering for High Frequency Spurious Harmonics Rejections", Technical Disclosure Commons, (December 13, 2022)