# US 12,120,753 B2 · Communication apparatus and communication method for multi-band random access > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,120,753 B2 - Document ID: US12120753B2 - Status: Granted - Kind: B2 - Application number: 17/293,864 - Filed: 2019-10-30 - Published: 2022-01-13 - Granted: 2024-10-15 - Earliest claimed: 2018-11-28 - Assignees: Panasonic Intellectual Property Corporation of America - Applicants: Panasonic Intellectual Property Corporation of America - Inventors: Lei Huang; Yoshio Urabe; Rojan Chitrakar - Web page: https://patentgrep.com/patent/US12120753B2 ## CPC - H04W 74/085: {collision avoidance} - H04W 72/0446: Resources in time domain, e.g. slots or frames - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04L 5/00: Arrangements affording multiple use of the transmission path - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A station apparatus includes a receiver and a controller. The receiver, in operation, receives a Trigger frame allocating Random Access Resource Units (RA-RUs) over multiple bands. The Trigger frame includes a User Info field that comprises a Band Indication subfield for specifying a first band among the multiple bands, an RU Allocation subfield for indicating a first RA-RU of one or more contiguous RA-RUs in the first band, and a Number of RA-RU subfield for indicating a number of the contiguous RA-RUs minus one in the first band. The controller, in operation: sets a first Orthogonal Frequency Division Multiple Access (OFDMA) random access backoff (OBO) counter to 0 if an initial value of the first OBO counter is not larger than a number of eligible RA-RUs in the first band, which is a subset of contiguous RA-RUs in the Trigger frame; and randomly selects one of the eligible RA-RUs. ## Claims ### Claim 1 A station (STA) apparatus comprising: a receiver which, in operation, receives a Trigger frame allocating Random Access Resource Units (RA-RUs) over multiple bands, the Trigger frame including a first User Info field that comprises a first Band Indication subfield for specifying a first band among the multiple bands, a first RU Allocation subfield for indicating a first RA-RU of one or more contiguous RA-RUs in the first band specified by the first Band Indication subfield, and a first Number of RA-RU subfield for indicating a number of the contiguous RA-RUs minus one in the first band specified by the first Band Indication subfield; and a controller which, in operation: sets a first Orthogonal Frequency Division Multiple Access (OFDMA) random access backoff (OBO) counter to 0 if an initial value of the first OBO counter is not larger than a number of first eligible RA-RUs in the first band, which is a first subset of contiguous RA-RUs specified by the Trigger frame; and randomly selects one of the first eligible RA-RUs in the first band. ### Claim 2 (depends on 1) The STA apparatus of claim 1, wherein an RA-RU is determined to be eligible if the STA apparatus supports all transmit parameters indicated in a Common Info field of the Trigger frame and in the first User Info field of the Trigger frame corresponding to the RA-RU; and if the STA apparatus is not associated with a Basic Service Set (BSS) it intends to transmit to and a predetermined subfield of the first User Info field of the Trigger frame corresponding to the RA-RU is a first predetermined number. ### Claim 3 (depends on 1) The STA apparatus of claim 1, wherein an RA-RU is determined to be eligible if the STA apparatus supports all transmit parameters indicated in a Common Info field of the Trigger frame and in the first User Info field of the Trigger frame corresponding to the RA-RU; and if the STA apparatus is an associated communication apparatus and a Transmitter Address (TA) field of the Trigger frame is set to a BSS identifier (ID) of an associated BSS and a predetermined subfield of the first User Info field of the Trigger frame corresponding to the RA-RU is a second predetermined number. ### Claim 4 (depends on 1) The STA apparatus of claim 1, wherein the first OBO counter corresponds to the multiple bands. ### Claim 5 (depends on 1) The STA apparatus of claim 1, wherein the Trigger frame includes a second Band Indication subfield for specifying a second band among the multiple bands, a second RU Allocation subfield for indicating a second RA-RU of one or more contiguous RA-RUs in the second band, and a second Number of RA-RU subfield for indicating a number of the contiguous RA-RUs minus one in the second band, and wherein a second subset of the contiguous RA-RUs specified by the Trigger frame constitutes second eligible RA-RUs in the second band, from which one eligible RA-RU is randomly selected, and the STA further comprises: a transmitter which, in operation, transmits a first Trigger Based Physical layer Protocol Data Unit (TB PPDU) in the selected first eligible RA-RU in the first band and transmits a second TB PPDU in the selected second eligible RA-RU in the second band if both the selected first eligible RA-RU in the first band and the selected second eligible RA-RU in the second band are considered to be idle, wherein the first and second TB PPDUs carry a same Medium Access Control Protocol Data Unit (MPDU) or Aggregate MPDU. ### Claim 6 (depends on 1) The STA apparatus of claim 1, wherein a range of a first OFDMA Contention Window (OCW), which corresponds to the first OBO counter, is specific to the type of STA apparatus. ### Claim 7 (depends on 6) The STA apparatus of claim 6, wherein the first OBO counter corresponds to the first band. ### Claim 8 (depends on 6) The STA apparatus of claim 6, wherein a second Band Indication subfield further specifies a second band among the multiple bands, and the controller, when in operation: sets a second OBO counter to 0 if an initial value of the second OBO counter is not larger than a number of eligible RA-RUs in the second band; and randomly selects one of the eligible RA-RUs in the second band for Trigger Based Physical layer Protocol Data Unit (TB PPDU) transmission; wherein the second OBO counter is initialized according to a second OCW. ### Claim 9 (depends on 8) The STA apparatus of claim 8, wherein the range of the first OCW is specific to the first band and a range of the second OCW is specific to the second band. ### Claim 10 (depends on 9) The STA apparatus of claim 9, further comprising: a transmitter which, in operation, transmits a first TB PPDU in the selected eligible RA-RU in the first band and a second TB PPDU in the selected eligible RA-RU in the second band if both the selected eligible RA-RUs are considered to be idle, wherein the first and second TB PPDUs carry a same Medium Access Control Protocol Data Unit (MPDU), or a same Aggregated MPDU (A-MPDU), or different MPDUs, or different A-MPDUs. ### Claim 11 (depends on 1) The STA apparatus of claim 1, wherein the first User Info field includes a subfield that is set to a first predetermined value to indicate the RA-RU(s) allocated by the first User Info field are reserved for associated STA apparatuses operating in one of the multiple bands. ### Claim 12 (depends on 11) The STA apparatus of claim 11, wherein the subfield is set to a second predetermined value to indicate the RA-RU(s) allocated by the first User Info field are reserved for STA apparatuses which are operating in one of the multiple bands and are not associated with a BSS they intend to transmit to. ### Claim 13 A communication method for uplink Orthogonal Frequency Division Multiple Access (OFDMA) based random access, the method comprising: initializing a first Orthogonal Frequency Division Multiple Access (OFDMA) random access backoff (OBO) counter according to a first OFDMA Contention Window (OCW); receiving a Trigger frame having Random Access Resource Units (RA-RUs) over multiple bands, the Trigger frame including a first User Info field that comprises a first Band Indication subfield for specifying a first band among the multiple bands, a first RU Allocation subfield for indicating a first RA-RU of one or more contiguous RA-RUs in the first band specified by the first Band Indication subfield, and a first Number of RA-RU subfield for indicating a number of the contiguous RA-RUs minus one in the first band specified by the first Band Indication subfield; setting the first OBO counter to 0 if an initial value of the first OBO counter is not larger than a number of first eligible RA-RUs in the first band, which is a first subset of contiguous RA-RUs specified by the Trigger frame; and randomly selecting one of the first eligible RA-RUs in each of the multiple bands. ### Claim 14 (depends on 13) The method of claim 13, further comprising: randomly selecting one of eligible RA-RUs in a second band further specified by a second Band Indication subfield; and transmitting a first Trigger Based Physical layer Protocol Data Unit (TB PPDU) carrying a Medium Access Control Protocol Data Unit (MPDU) or Aggregate MPDU in the selected eligible RA-RU in the first band and a second TB PPDU carrying the same MPDU or Aggregate MPDU in the selected eligible RA-RU in the second band if both the selected eligible RA-RUs are considered to be idle. ### Claim 15 (depends on 13) The method of claim 13, wherein a second Band Indication subfield further specifies a second band among the multiple bands, and the method further comprising: initializing a second OBO counter according to a second OCW; setting the second OBO counter to 0 if an initial value of the second OBO is not larger than a number of eligible RA-RUs in the second band, which is a second subset of the contiguous RA-RUs in the Trigger frame; and randomly selecting one of the eligible RA-RUs in the second band for Trigger Based Physical layer Protocol Data Unit (TB PPDU) transmission.