47 CFR § 90.370 - Permitted frequencies.
(a) Dedicated Short-Range Communications Service (DSRCS) systems are permitted to operate in the 5895–5925 MHz band.
(b) DSRCS authorizations granted prior to the July 2, 2021 may remain on existing frequencies in the 5850–5895 MHz band until July 5, 2022, at which time they may only operate in the 5895–5925 MHz band.
(c) Frequencies in the 5895–5925 MHz band will not be assigned for the exclusive use of any licensee; Channels are available on a shared basis only for use in accordance with the Commission's rules. All licensees shall cooperate in the selection and use of channels in order to reduce interference. This includes monitoring for communications in progress and any other measures as may be necessary to minimize interference.
(d) Licensees of Roadside Units (RSUs) suffering or causing harmful interference within a communications zone, as defined in § 90.375 of this part, are expected to cooperate and resolve this problem by mutually satisfactory arrangements. If the licensees are unable to do so, the Commission may impose restrictions including specifying the transmitter power, antenna height and direction, additional filtering, or area or hours of operation of the stations concerned. The use of any channel at a given geographical location may be denied when, in the judgment of the Commission, its use at that location is not in the public interest; use of any such channel may be restricted as to specified geographical areas, maximum power, or such other operating conditions, contained in this part or in the station authorization.