In a ruling issued on the 2nd of October 2020, the Federal Communications Commission (FCC) in the USA announced that the amateur radio service is going to lose access to the 3.4 GHz microwave band. It is proposed that the spectrum from 3.3 to 3.55 GHz be cleared for 5G networks.
Up to now, radio amateurs in the US had a secondary allocation from 3.3 to 3.5 GHz based on a non-interference basis to primary users. The FCC have now proposed clearing 3.4 to 3.5 GHz in the short term and 3.3 to 3.4 GHz at a later date.
Excerpt from the ruling regarding the amateur allocation...
C. Sunset of Secondary Amateur Allocation
allocation from the 3.3-3.5 GHz band. As we did with radiolocation operations, we adopt changes to our rules today that provide for the sunset of the secondary amateur allocation in the band, but allow continued use of the band for amateur operations, pending resolution of the issues raised in the Further Notice. Secondary non-federal amateur licensees operating in this band as of the effective date of this Report and Order may continue while the Commission finalizes plans to reallocate spectrum in the 3.45- 3.55 GHz band. Authorizations will sunset on a date consistent with the first possible grant of flexible use authorizations to new users in that portion of the band—for example, 90 days after the close of the auction if we adopt a licensing scheme that will result in an auction to assign licenses.77 We revise the Table of Allocations accordingly.78
34. Clearing all secondary operations, including amateur operations, from this spectrum will allow us to maximize the band for potential flexible use operations in the future. Further, to prevent adjacent-channel issues and to preserve the possibility of additional clearing for flexible use licensing below 3.45 GHz, we find that sunsetting the secondary amateur allocation from the entire 3.3-3.5 GHz portion of the band is in the public interest.
In a separate auction for some spectrum at 3.6 GHz recently, some $4.5 Billion was raised so the spectrum around 3.4 GHz may well raise a similar amount.
The ARRL and AMSAT had made a case for continued use of the shared amateur allocation but the FCC has now rejected this.
The big losers in all this is probably AMSAT and the amateur radio satellite community. The 3.4 GHz (9cm) band had possibilities for uplinks and downlinks for geostationary satellites or lunar probes. With the US losing the band, it will probably curtail such possibilities.
The loss of an amateur band in the low GHz region also represents the thin end of the wedge. With the demand for spectrum by commercial and other interests, many of the amateur bands worldwide are potentially under threat.