# US 11,122,567 B2 · Coexistence techniques for wide area network devices operating in unlicensed bands > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,122,567 B2 - Document ID: US11122567B2 - Status: Granted - Kind: B2 - Application number: 16/181,078 - Filed: 2018-11-05 - Published: 2019-04-04 - Granted: 2021-09-14 - Earliest claimed: 2013-11-26 - Assignees: Marvell Asia Pte Ltd - Applicants: Marvell World Trade Ltd. - Inventors: Yakun Sun; Hongyuan Zhang; Mingguang Xu; Liwen Chu; Hui-Ling Lou - Web page: https://patentgrep.com/patent/US11122567B2 ## CPC - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04W 16/16: for PBS [Private Base Station] arrangements - H04W 48/16: Discovering, processing access restriction or access information - H04W 72/02: Selection of wireless resources by user or terminal - H04W 88/06: adapted for operation in multiple networks {or having at least two operational modes}, e.g. multi-mode terminals - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A communication device associated with a first wireless communication network transmits an indication that a communication channel in an unlicensed frequency band is being utilized by the first wireless communication network. The indication is transmitted to an access point of a second wireless communication network. The first wireless communication network utilizes a first wireless communication protocol developed for use in licensed frequency bands, and the second wireless communication network utilizes a second wireless communication protocol developed for use in the unlicensed frequency band. The indication is transmitted by the communication device to prompt the access point of the second wireless communication network, to determine that i) the communication channel cannot be used by the second wireless communication network, or ii) the second wireless communication network is to temporarily yield the communication channel to the first wireless communication network. ## Claims ### Claim 1 A method, comprising: receiving, at an access point of a first wireless communication network, an indication that a communication channel in an unlicensed frequency band is being utilized by a second wireless communication network, wherein the first wireless communication network utilizes a first wireless communication protocol developed for use in the unlicensed frequency band, wherein the second wireless communication network utilizes a second wireless communication protocol developed for use in frequency bands that are licensed by a government entity for wireless communication applications, and wherein the government entity does not require licenses to use the unlicensed frequency band; and in response to receiving the indication that the communication channel in the unlicensed frequency band is being utilized by the second wireless communication network that utilizes the second wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications, determining, at the access point of the first wireless communication network, that i) the communication channel cannot be used by the first wireless communication network, or ii) the first wireless communication network is to temporarily yield the communication channel to the second wireless communication network. ### Claim 2 (depends on 1) The method of claim 1, wherein receiving the indication that the communication channel in the unlicensed frequency band is being utilized by the second wireless communication network comprises: receiving, at the access point of the first wireless communication network, an announcement frame that conforms to the first wireless communication protocol developed for use in the unlicensed frequency band, wherein the announcement frame indicates that the communication channel in the unlicensed frequency band is being utilized, and wherein the announcement frame is received from a communication device of the second wireless communication network that utilizes the second wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications. ### Claim 3 (depends on 2) The method of claim 2, wherein the announcement frame is received by the access point of the first wireless communication network via the communication channel in the unlicensed frequency band. ### Claim 4 (depends on 2) The method of claim 2, wherein the announcement frame is a beacon frame that conforms to the first wireless communication protocol developed for use in the unlicensed frequency band. ### Claim 5 (depends on 2) The method of claim 2, wherein the announcement frame is a request-to-send (RTS) frame that conforms to the first wireless communication protocol developed for use in the unlicensed frequency band. ### Claim 6 (depends on 2) The method of claim 2, wherein the announcement frame is a clear-to-send (CTS) frame that conforms to the first wireless communication protocol developed for use in the unlicensed frequency band. ### Claim 7 (depends on 6) The method of claim 6, wherein the announcement frame is a CTS-to-self frame that conforms to the first wireless communication protocol developed for use in the unlicensed frequency band. ### Claim 8 (depends on 2) The method of claim 2, wherein the announcement frame is received by the access point of the first wireless communication network within a subframe defined by the second wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications. ### Claim 9 (depends on 8) The method of claim 8, wherein the announcement frame is received by the access point of the first wireless communication network within a multicast-broadcast single frequency network (MBSFN) subframe defined by the second wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications. ### Claim 10 (depends on 8) The method of claim 8, wherein the announcement frame is received by the access point of the first wireless communication network within an almost blank subframe (ABS) defined by the second wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications. ### Claim 11 A method, comprising: transmitting, by a communication device associated with a first wireless communication network, an indication that a communication channel in an unlicensed frequency band is being utilized by the first wireless communication network, wherein the indication is transmitted to an access point of a second wireless communication network, wherein the first wireless communication network utilizes a first wireless communication protocol developed for use in frequency bands that are licensed by a government entity for wireless communication applications, wherein the government entity does not require licenses to use the unlicensed frequency band, and wherein the second wireless communication network utilizes a second wireless communication protocol developed for use in the unlicensed frequency band; wherein the indication is transmitted by the communication device to prompt the access point of the second wireless communication network, to determine that i) the communication channel cannot be used by the second wireless communication network, or ii) the second wireless communication network is to temporarily yield the communication channel to the first wireless communication network. ### Claim 12 (depends on 11) The method of claim 11, further comprising: generating, at the communication device associated with the first wireless communication network, an announcement frame that conforms to the second wireless communication protocol developed for use in the unlicensed frequency band, wherein the announcement frame indicates that the communication channel in the unlicensed frequency band is being utilized; wherein transmitting the indication comprises transmitting the announcement frame. ### Claim 13 (depends on 12) The method of claim 12, wherein transmitting the announcement frame comprises transmitting the announcement frame via the communication channel in the unlicensed frequency band. ### Claim 14 (depends on 12) The method of claim 12, wherein the announcement frame is a beacon frame that conforms to the second wireless communication protocol developed for use in the unlicensed frequency band. ### Claim 15 (depends on 12) The method of claim 12, wherein the announcement frame is a request-to-send (RTS) frame that conforms to the second wireless communication protocol developed for use in the unlicensed frequency band. ### Claim 16 (depends on 12) The method of claim 12, wherein the announcement frame is a clear-to-send (CTS) frame that conforms to the second wireless communication protocol developed for use in the unlicensed frequency band. ### Claim 17 (depends on 16) The method of claim 16, wherein the announcement frame is a CTS-to-self frame that conforms to the second wireless communication protocol developed for use in the unlicensed frequency band. ### Claim 18 (depends on 12) The method of claim 12, wherein transmitting the announcement frame comprises transmitting the announcement frame within a subframe defined by the first wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications. ### Claim 19 (depends on 18) The method of claim 18, wherein the announcement frame is transmitted within a multicast-broadcast single frequency network (MBSFN) subframe defined by the first wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications. ### Claim 20 (depends on 18) The method of claim 18, wherein the announcement frame is transmitted within an almost blank subframe (ABS) defined by the first wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications. ### Claim 21 An apparatus, comprising: a network interface device associated with a first wireless communication network that utilizes a first wireless communication protocol developed for use in frequency bands that are licensed by a government entity for wireless communication applications, the network interface device having one or more integrated circuit devices configured to: transmit an indication that a communication channel in an unlicensed frequency band is being utilized by the first wireless communication network, wherein the indication is transmitted to an access point of a second wireless communication network, wherein the government entity does not require licenses to use the unlicensed frequency band, and wherein the second wireless communication network utilizes a second wireless communication protocol developed for use in the unlicensed frequency band; wherein the indication is transmitted by the network interface device to prompt the access point of the second wireless communication network, to determine that i) the communication channel cannot be used by the second wireless communication network, or ii) the second wireless communication network is to temporarily yield the communication channel to the first wireless communication network. ### Claim 22 (depends on 21) The apparatus of claim 21, wherein the one or more integrated circuit devices are further configured to: generate an announcement frame that conforms to the second wireless communication protocol developed for use in the unlicensed frequency band, wherein the announcement frame indicates that the communication channel in the unlicensed frequency band is being utilized; and transmit the indication by transmitting the announcement frame. ### Claim 23 (depends on 22) The apparatus of claim 22, wherein the one or more integrated circuit devices are further configured to: transmit the announcement frame via the communication channel in the unlicensed frequency band. ### Claim 24 (depends on 22) The apparatus of claim 22, wherein the announcement frame is one of: a beacon frame that conforms to the second wireless communication protocol developed for use in the unlicensed frequency band, a request-to-send (RTS) frame that conforms to the second wireless communication protocol developed for use in the unlicensed frequency band, a clear-to-send (CTS) frame that conforms to the second wireless communication protocol developed for use in the unlicensed frequency band, or a CTS-to-self frame that conforms to the second wireless communication protocol developed for use in the unlicensed frequency band. ### Claim 25 (depends on 22) The apparatus of claim 22, wherein the one or more integrated circuit devices are further configured to: transmit the announcement frame within a subframe defined by the first wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications. ### Claim 26 (depends on 25) The apparatus of claim 25, wherein the one or more integrated circuit devices are further configured to transmit the announcement frame within one of: a multicast-broadcast single frequency network (MBSFN) subframe defined by the first wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications, or an almost blank subframe (ABS) defined by the first wireless communication protocol developed for use in frequency bands that are licensed by the government entity for wireless communication applications.