This is an interesting article: mainly about a miniature Tuneable YIG – yttrium-iron-garnet – filter that could replace many fixed filters.
Quote “”Wireless devices use different filters for different frequencies, with the effect that covering all frequencies or bands requires large numbers of filters that take up substantial space. (The typical smartphone includes upwards of 100 filters, to ensure that signals from different bands don’t interfere with one another.)””
The article also talks about the “FR3 band” of 7 to 24GHz for the 6G smartphones.
https://techxplore.com/news/2024-05-6g-generation-wireless-communications.html