Wireless device, a network node and methods therein for enabling and performing an uplink control channel transmission

Abstract

A method performed by a wireless device for performing an uplink control channel transmission in a serving cell in a wireless communications network is provided. The wireless device is configured with a set of serving cell(s) in the wireless communications network. First, the wireless device determines a number of serving cells of the set of serving cell(s) that are relevant to consider when performing the uplink control channel transmission in the serving cell. Secondly, the wireless device selects an uplink control channel format from a set of uplink control channel formats for uplink control channel transmissions based on the determined number of serving cells. Then, the wireless device performs the uplink control channel transmission in the serving cell using the selected uplink control channel format. A wireless device for performing an uplink control channel transmission in a serving cell in a wireless communications network is also provided.

1 . A method performed by a wireless device for performing an uplink control channel transmission in a serving cell in a wireless communications network when the wireless device is configured with a set of serving cells based on Radio Resource Control, RRC, and Medium Access Control Elements, MAC CE, signalling, comprising said serving cell, in the wireless communications network, the method comprising 
 performing the uplink control channel transmission in the serving cell by using an uplink control channel format from a set of uplink control channel formats based on a number of serving cells that the wireless device has been scheduled on by a dynamic scheduling signalling from a network node.   
     
     
         2 . The method according to  claim 1 , wherein the number of serving cells of the set of serving cells being the number of serving cells that the wireless device has been scheduled on within a configured time period. 
     
     
         3 . The method according to  claim 1 , wherein the uplink control channel format for the uplink control channel transmission is selected from the set of uplink control channel formats based on one or more threshold values for the determined number of serving cells. 
     
     
         4 . The method according to  claim 3 , wherein the uplink control channel format for the uplink control channel transmission is selected from the set of uplink control channel formats further based on the existence of and/or the length of a periodic Channel State Information, CSI, in the wireless device. 
     
     
         5 . The method according to  claim 1 , wherein the uplink control channel transmission in the serving cell using the selected uplink control channel format is performed according to one or more of the following:
 at the beginning of the next subsequent subframe in the wireless communications network,   at the beginning of the next subsequent radio frame in the wireless communications network,   - according to information received from a network node in the wireless communications network,   upon or after the expiry of a timer for switching the uplink control channel format for uplink control channel transmissions, and   at a fixed or predetermined time instant.   
     
     
         6 . The method according to  claim 5 , wherein the uplink control channel transmission in the serving cell using the selected uplink control channel format is performed based on the configuration of the serving cell. 
     
     
         7 . The method according to  claim 1 , further comprising receiving information indicating the set of uplink control channel formats for uplink control channel transmissions from a network node in the wireless communications network. 
     
     
         8 . The method according to  claim 7 , wherein the information is received in a Radio Resource Control, RRC, message. 
     
     
         9 . A wireless device for performing an uplink control channel transmission in a serving cell in a wireless communications network when the wireless device is configured with a set of serving cells based on Radio Resource Control, RRC, and Medium Access Control Elements, MAC CE, signalling, comprising said serving cell, in the wireless communications network, the wireless device comprising a processor and a memory, said memory containing instructions executable by said processor, wherein the wireless device is operative to 
 perform the uplink control channel transmission in the serving cell by using an uplink control channel format from a set of uplink control channel formats based on a number of serving cells that the wireless device has been scheduled on by a dynamic scheduling signalling from a network node.   
     
     
         10 . The wireless device according to  claim 9 , wherein the number of serving cells of the set of serving cells being the number of serving cells that the wireless device has been scheduled on within a configured time period. 
     
     
         11 . The wireless device according to  claim 9 , wherein the uplink control channel format for the uplink control channel transmission is selected from the set of uplink control channel formats based on one or more threshold values for the determined number of serving cells. 
     
     
         12 . The wireless device according to  claim 9 , wherein the uplink control channel format for the uplink control channel transmission is selected from the set of uplink control channel formats further based on the existence of and/or the length of a periodic Channel State Information, CSI, in the wireless device. 
     
     
         13 . The wireless device according to  claim 9 , wherein the uplink control channel transmission in the serving cell using the selected uplink control channel format is performed according to one or more of the following:
 at the beginning of the next subsequent subframe in the wireless communications network,   at the beginning of the next subsequent radio frame in the wireless communications network,   according to information received from a network node in the wireless communications network,   upon or after the expiry of a timer for switching the uplink control channel format for uplink control channel transmissions, and   at a fixed or predetermined time instant.   
     
     
         14 . The wireless device according to  claim 9 , wherein the uplink control channel transmission in the serving cell using the selected uplink control channel format is performed based on the configuration of the serving cell. 
     
     
         15 . The wireless device according to  claim 9 , further comprising receiving information indicating the set of uplink control channel formats for uplink control channel transmissions from a network node in the wireless communications network. 
     
     
         16 . The wireless device according to  claim 15 , wherein the information is received in a Radio Resource Control, RRC, message.