[[["容易理解","easyToUnderstand","thumb-up"],["確實解決了我的問題","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["難以理解","hardToUnderstand","thumb-down"],["資訊或程式碼範例有誤","incorrectInformationOrSampleCode","thumb-down"],["缺少我需要的資訊/範例","missingTheInformationSamplesINeed","thumb-down"],["翻譯問題","translationIssue","thumb-down"],["其他","otherDown","thumb-down"]],["上次更新時間：2025-09-04 (世界標準時間)。"],[],[],null,["# Priority Access Licenses\n\nThe Citizens Broadband Radio Service (CBRS) band operates as a shared spectrum with three tiers\nof users. The [Priority Access License (PAL)](/spectrum-access-system/docs/key-terms#pal)\nresides in Tier 2. The following diagram shows the tiers in the CBRS band.\n[](/static/spectrum-access-system/docs/images/about-pal.svg) Tiers in the CBRS band (click to enlarge)\n\nInterference protection\n-----------------------\n\nTo get protection from\n[General Authorized Access (GAA)](/spectrum-access-system/docs/key-terms#gaa)---users\nin the third tier---interference, you can buy a PAL at an auction. Each\nPAL receives interference protection in\n[PAL Protection Areas (PPAs)](/spectrum-access-system/docs/key-terms#ppa)\non a 10-MHz channel from 3550 MHz to 3650 MHz. The interference\nprotection tiers are explained as follows.\n\n### Tier 1\n\nTier 1 [incumbents](/spectrum-access-system/docs/key-terms#incubment) get\nprotection from both PAL and GAA users. Within a protection area, channel\navailability and power limitations apply to PAL and GAA users equally.\n\nFor example, in a [Dynamic Protection Area (DPA)](/spectrum-access-system/docs/key-terms#dpa),\ngrants on PAL channels can be suspended due to DPA activations. The CBSDs\ncan request grants on GAA channels, but aren't protected from GAA interference.\n\n### Tier 2\n\nTier 2 PAL users get interference protection from GAA users. When a PPA goes\ninto effect, GAA users with grants on PAL channels that are determined to cause\ninterference to the PPA have their grants terminated with [error code 500](/spectrum-access-system/docs/cbsd/errors-grant-suspension#troubleshooting-matrix).\nSometimes, the grant termination includes suggested operating parameters such as\na lower [Effective Isotropic Radiated Power (EIRP)](/spectrum-access-system/docs/key-terms#eirp).\n\nAlthough PAL users have a right to protection in the entire county, they are\nprotected only where they have deployed CBSDs and only on their\nPAL channels. The PPAs generally cover only part of a county's license area,\nleaving space where GAA users can operate freely on PAL channels. In every\ncounty, there are eight channels that are never allocated for PAL. That means\nthat all 15 channels could be available to GAA users in any county.\n\n### Tier 3\n\nTier 3 GAA users are unlicensed with no guaranteed interference protection. In this tier,\nCBSD operates as licensed-by-rule.\n\nPAL auction\n-----------\n\nThe PAL auction was closed on August 25, 2020. A maximum of seven channels were\nauctioned in each US county where a single operator was limited to a maximum of\nfour channels in any county. The [Federal Communications Commission (FCC)](/spectrum-access-system/docs/key-terms#fcc)\ndatabase publishes the list of PAL licensees. Licenses are valid for ten years.\nPAL licensees can use their PAL licenses with any SAS with a start\ndate indicated in the [CBRS status summary](https://cbrs.wirelessinnovation.org/cbrs-status-summary).\n\nPAL channel allocation\n----------------------\n\nSAS administrators coordinated to develop a methodology for PAL\nchannel allocation in accordance with the CBRS functional and\noperational requirement developed in WInnforum. The methodology is developed by\nreceiving the inputs from each operator on their channel preference for their\nauctioned logical PAL channels.\n\nAll PAL licensees received information on the PAL Channel Assignment Procedure\nin December 2020. If you didn't get the email about the PAL channel assignment\nprocedure, or if you want to know more about the assignment procedure, write an\nemail to SAS administrators at\n[cbrs_pal_channels@outlook.com](mailto:cbrs_pal_channels@outlook.com).\n\nSecondary market\n----------------\n\nThe PAL licensees can sell or sub-license their PALs to other operators for all\nor part of the license area. Sub-license agreements can be recorded by Google\nSAS in the [FCC Universal Licensing System (ULS) database](https://www.fcc.gov/wireless/universal-licensing-system).\nTo verify a licensee's claim of a PAL or sub-licensed PAL, SAS\nchecks the FCC ULS database.\n\nWhat's next\n-----------\n\n- Learn how to [use PALs in the SAS Portal](/spectrum-access-system/docs/use-pals).\n- Learn about [SAS sync (or IAP)](/spectrum-access-system/docs/sas-sync).\n- Learn about [Spectrum Access System](/spectrum-access-system/docs/overview).\n- Learn about [key SAS terms](/spectrum-access-system/docs/key-terms).\n- [Troubleshoot SAS issues](/spectrum-access-system/docs/troubleshooting)."]]
