---
kind: "section"
citation: "47 C.F.R. § 90.390"
title: "47"
number: "90.390"
heading: "Channels and priority communications."
url: "https://uscodex.org/cfr/47/90.390"
---

# §90.390. Channels and priority communications.

- (a) **Channels.** C-V2X may operate on the following band segments:
- (b) **Safety/public safety priority.** The following access priority governs all C-V2X operations:
  - (1) Communications involving the safety of life have access priority over all other C-V2X communications;
  - (2) C-V2X communications involving public safety have access priority over all other C-V2X except those communications described in (b)(1) of this section. Roadside Units (RSUs) operated by State or local governmental entities are presumptively engaged in public safety priority communications.
- (c) **Non-priority communications.** C-V2X communications not listed in [paragraph (b)](#b) of this section, are non-priority communications.
  - (1) If a dispute arises concerning non-priority communications, the licensee of the later-registered RSU must accommodate the operation of the early registered RSU, i.e., interference protection rights are date-sensitive, based on the date that the RSU is first registered (see [§ 90.389](/cfr/47/90.389.md)) and the later-registered RSU must modify its operations to resolve the dispute in accordance with [paragraph (c)(2)](#c-2) of this section.
  - (2) For purposes of this [paragraph (c)](#c), objectionable interference will be considered to exist when the Commission receives a complaint and the difference in signal strength between the earlier-registered RSU and the later-registered RSU is 18 dB or less (co-channel). Later-registered RSUs causing objectionable interference must correct the interference immediately unless written consent is obtained from the licensee of the earlier-registered RSU.

## Notes

### Amendments

[89 FR 100852, Dec. 13, 2024; 90 FR 5725, Jan. 17, 2025]

### Source

Source: 89 FR 100852, Dec. 13, 2024, unless otherwise noted.

### Source

Source: 60 FR 15253, Mar. 23, 1995, unless otherwise noted.

### Authority

Authority: 47 U.S.C. 154(i), 161, 303(g), 303(r), 332(c)(7), 1401-1473

### Source

Source: 43 FR 54791, Nov. 22, 1978, unless otherwise noted.

### Amendments

[89 FR 100852, Dec. 13, 2024; 90 FR 5725, Jan. 17, 2025]