# US 10,375,690 B2 · Special subframe configuration in unlicensed spectrum > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,375,690 B2 - Document ID: US10375690B2 - Status: Granted - Kind: B2 - Application number: 14/819,178 - Filed: 2015-08-05 - Published: 2016-02-11 - Granted: 2019-08-06 - Earliest claimed: 2014-08-08 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Wanshi Chen; Tao Luo; Ravi Teja Sukhavasi - Web page: https://patentgrep.com/patent/US10375690B2 ## CPC - H04W 72/0446: Resources in time domain, e.g. slots or frames - H04L 1/1887: {Scheduling and prioritising arrangements} - H04L 5/00: Arrangements affording multiple use of the transmission path - H04W 74/0808: using carrier sensing, e.g. carrier sense multiple access [CSMA] - H04W 84/045: {using private Base Stations, e.g. femto Base Stations, home Node B} - 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 Apparatuses and methods for special subframe configuration in unlicensed spectrum are disclosed. For example, the disclosure presents an example method including identifying a time period for an extended clear channel assessment (ECCA) operation. Further, the example method may include determining a guard period portion included in a special subframe of a frame structure based on the identified time period. An apparatus may include means for identifying a time period for an extended clear channel assessment (ECCA) operation. Further, the example apparatus may include means for determining a guard period portion included in a special subframe of a frame structure based on the identified time period. ## Claims ### Claim 1 A method for configuring special subframes in a wireless communication system, comprising: identifying, by a load-based equipment (LBE), a time period for an extended clear channel assessment (ECCA) operation that determines whether a channel is clear for data communication, wherein the time period for the ECCA operation is based on an integer, the integer being randomly selected from a range between one and an upper limit integer or is an integer associated with a network entity; determining, by the LBE, a special subframe configuration for a special subframe of a frame structure and a guard period portion included in the special subframe based on the integer, the special subframe comprising an uplink (UL) portion, the guard period portion and a downlink (DL) portion; and transmitting, by the LBE via a broadcast message or a dedicated message, the special subframe configuration including a duration for the guard period portion that is equal to or greater than the identified time period, wherein a device receiving the transmitted broadcast message or dedicated message performs the ECCA operation in accordance to the identified time period. ### Claim 2 (depends on 1) The method of claim 1, wherein identifying the time period for the ECCA operation includes calculating, by the LBE, the time period by multiplying a clear channel assessment (CCA) observation time by the randomly selected integer. ### Claim 3 (depends on 1) The method of claim 1, wherein the guard period portion is determined dynamically in a frame-by-frame or a subframe-by-subframe basis. ### Claim 4 (depends on 1) The method of claim 1, wherein identifying the time period for the ECCA operation includes calculating, by the LBE, the time period by multiplying a CCA observation time by the integer associated with the network entity. ### Claim 5 (depends on 1) The method of claim 1, wherein determining the guard period portion includes determining the guard period portion based on at least one of a time offset or a minimal duration of the guard period portion. ### Claim 6 (depends on 1) The method of claim 1, wherein determining the guard period portion includes determining the guard period portion based on a set of supported guard periods. ### Claim 7 (depends on 6) The method of claim 6, wherein transmitting the duration for the guard period portion further comprises transmitting durations for the set of supported guard periods in a broadcast message or a dedicated message. ### Claim 8 (depends on 1) The method of claim 1, further comprising: determining, by the LBE, either the DL portion or the UL portion of the special subframe; and calculating, by the LBE, a remaining portion of the special subframe based on the determined guard period portion and the determined DL portion or UL portion. ### Claim 9 (depends on 8) The method of claim 8, wherein determining either a DL portion or an UL portion of the special subframe is based on information indicated in the broadcast message or the dedicated message. ### Claim 10 (depends on 1) The method of claim 1, wherein determining the guard period portion in the special subframe includes determining a guard period for a downlink ECCA operation or for an uplink ECCA operation. ### Claim 11 (depends on 1) The method of claim 1, further comprising identifying two or more sets of supported guard periods corresponding to two or more special subframes based on signaling received from a network entity. ### Claim 12 (depends on 1) The method of claim 1, wherein the duration for the guard period portion equals one plus ceiling of (the randomly selected integer times the ECCA observation time divided by a duration of a symbol). ### Claim 13 An apparatus for configuring special subframes in a wireless communication system, comprising: means for identifying a time period for an extended clear channel assessment (ECCA) operation that determines whether a channel is clear for data communication, wherein the time period for the ECCA operation is based on an integer, the integer being randomly selected from a range between one and an upper limit integer or an integer associated with a network entity; means for determining a special subframe configuration for a special subframe of a frame structure and a guard period portion included in the special subframe based on the integer, the special subframe comprising an uplink (UL) portion, the guard period portion and a downlink (DL) portion; and means for transmitting, via a broadcast message or a dedicated message, the special subframe configuration including a duration for the guard period portion that is equal to or greater than the identified time period, wherein a device receiving the transmitted broadcast message or dedicated message performs the ECCA operation in accordance to the identified time period. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the means for identifying the time period for the ECCA operation includes means for calculating the time period by multiplying a clear channel assessment (CCA) observation time by the randomly selected integer. ### Claim 15 (depends on 13) The apparatus of claim 13, wherein the guard period portion is determined dynamically in a frame-by-frame or a subframe-by-subframe basis. ### Claim 16 (depends on 13) The apparatus of claim 13, wherein the means for identifying the time period for the ECCA operation includes means for calculating the time period by a CCA observation time by the integer associated with the network entity. ### Claim 17 (depends on 13) The apparatus of claim 13, wherein the duration for the guard period portion equals one plus ceiling of (the randomly selected integer times the ECCA observation time divided by a duration of a symbol). ### Claim 18 An apparatus for configuring special subframes in a wireless communication system, comprising: a memory configured to store instructions; and at least one processor communicatively coupled with the memory, wherein the at least one processor is configured to execute the instructions to: identify a time period for an extended clear channel assessment (ECCA) operation that determines whether a channel is clear for data communication, wherein the time period for the ECCA operation is based on an integer, the integer being randomly selected from a range between one and an upper limit integer or is an integer associated with a network entity; determine a special subframe configuration for a special subframe of a frame structure and a guard period portion included in the special subframe based on the integer, the special subframe comprising an uplink (UL) portion, the guard period portion and a downlink (DL) portion; and transmit, via a broadcast message or a dedicated message, the special subframe configuration including a duration for the guard period portion that is equal to or greater than the identified time period, wherein a device receiving the transmitted broadcast message or dedicated message performs the ECCA operation in accordance to the identified time period. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein the at least one processor is configured to execute further instructions to calculate the time period by multiplying a clear channel assessment (CCA) observation time by the randomly selected integer. ### Claim 20 (depends on 18) The apparatus of claim 18, wherein the guard period portion is determined dynamically in a frame-by-frame or a subframe-by-subframe basis. ### Claim 21 (depends on 18) The apparatus of claim 18, wherein the at least one processor is configured to execute further instructions to calculate the time period by multiplying a CCA observation time by the integer associated with the network entity. ### Claim 22 (depends on 18) The apparatus of claim 18, wherein the duration for the guard period portion equals one plus ceiling of (the randomly selected integer times the ECCA observation time divided by a duration of a symbol). ### Claim 23 A non-transitory computer-readable medium storing executable code for configuring special subframes in a wireless communication system, comprising instructions, that when executed by a processor, cause the processor to: identify a time period for an extended clear channel assessment (ECCA) operation that determines whether a channel is clear for data communication, wherein the time period for the ECCA operation is based on an integer, the integer being randomly selected from a range between one and an upper limit integer or is an integer associated with a network entity; determine a special subframe configuration for a special subframe of a frame structure and a guard period portion included in the special subframe based on the integer, the special subframe configuration comprising an uplink (UL) portion, the guard period portion and a downlink (DL) portion; and transmit, via a broadcast message or a dedicated message, the special subframe configuration including a duration for the guard period portion that is equal to or greater than the identified time period, wherein a device receiving the transmitted broadcast message or dedicated message performs the ECCA operation in accordance to the identified time period. ### Claim 24 (depends on 23) The non-transitory computer-readable medium of claim 23, further comprising instructions, that when executed by the processor, cause the processor to calculate the time period by multiplying a clear channel assessment (CCA) observation time by the randomly selected integer. ### Claim 25 (depends on 23) The non-transitory computer-readable medium of claim 23, wherein the guard period portion is determined dynamically in a frame-by-frame or a subframe-by-subframe basis. ### Claim 26 (depends on 23) The non-transitory computer-readable medium of claim 23, further comprising instructions, that when executed by the processor, cause the processor to calculate the time period by multiplying a CCA observation time by the integer associated with the network entity. ### Claim 27 (depends on 23) The non-transitory computer-readable medium of claim 23, wherein the duration for the guard period portion equals one plus ceiling of (the randomly selected integer times the ECCA observation time divided by a duration of a symbol).