Informing in groups of IAB MT-DU resource misalignment
Systems and methods for reducing signaling overhead between an Integrated Access and Backhaul (IAB) node and its parent node when switching between timing alignment cases are disclosed. In some embodiments, the method comprises sending one or more sets of desired numbers of guard symbols for two or more timing switching groups, respectively. The method further comprises receiving one or more sets of provided numbers of guard symbols for the two or more timing switching groups, respectively and determining available time resources for uplink transmission and/or downlink reception in two adjacent time units based on one of the one or more sets of provided numbers of guard symbols for one of the two or more timing switching groups that corresponds to timing alignment cases used in the two adjacent time units.
1 . A method performed by an Integrated Access and Backhaul, IAB, node, comprising:
sending to a parent IAB node, one or more sets of desired numbers of guard symbols for two or more timing switching groups, respectively, wherein:
each timing switching group of the two or more timing switching groups comprises one or more timing alignment cases; and
each set of desired numbers of guard symbols comprises a desired number of guard symbols for the one or more timing alignment cases comprised in the respective timing switching group of the two or more timing switching groups;
receiving, from the parent IAB node, one or more sets of provided numbers of guard symbols for the two or more timing switching groups, respectively; and
determining available time resources for one or more of: uplink transmission and downlink reception in two adjacent time units based on one of the one or more sets of provided numbers of guard symbols for one of the two or more timing switching groups that corresponds to timing alignment cases used in the two adjacent time units.
2 . The method of claim 1 , wherein:
the IAB node comprises an IAB-Mobility Termination, IAB-MT, and an IAB-Distributed Unit, IAB-DU; and
the desired numbers of guard symbols are numbers of symbols that the IAB-MT indicates to the parent IAB node not to use for the IAB-MT in slots where the IAB node transitions between the IAB-MT and the IAB-DU.
3 . The method of claim 1 , wherein:
the IAB node comprises an IAB-Mobility Termination, IAB-MT, and an IAB-Distributed Unit, IAB-DU; and
the provided numbers of guard symbols are numbers of symbols that are not be used for the IAB-MT in slots where the IAB node transitions between IAB-MT and IAB-DU.
4 . The method of claim 1 further comprising performing one or more of: uplink transmission and downlink reception in the two adjacent time units based on the determined available time resources.
5 . The method of claim 1 , wherein the two or more timing switching groups comprise one or more of the following:
a first timing switching group comprising one or more of the following timing alignment cases:
Switching from IAB-MT Rx in timing Case #1 to IAB-DU Tx in timing Case #1;
Switching from IAB-MT Rx in timing Case #1 to IAB-DU Rx in timing Case #1;
Switching from IAB-MT Tx in timing Case #1 to IAB-DU Tx in timing Case #1;
Switching from IAB-MT Tx in timing Case #1 to IAB-DU Rx in timing Case #1;
Switching from IAB-DU Rx in timing Case #1 to IAB-MT Tx in timing Case #1;
Switching from IAB-DU Rx in timing Case #1 to IAB-MT Rx in timing Case #1;
Switching from IAB-DU Tx in timing Case #1 to IAB-MT Tx in timing Case #1;
Switching from IAB-DU Tx in timing Case #1 to IAB-MT Rx in timing Case #1;
a second timing switching group comprising one or more of the following timing alignment cases:
Switching from IAB-MT Rx in timing Case #1 to IAB-DU Tx in timing Case #6;
Switching from IAB-MT Rx in timing Case #1 to IAB-DU Rx in timing Case #7;
Switching from IAB-MT Tx in timing Case #1 to IAB-DU Tx in timing Case #6;
Switching from IAB-MT Tx in timing Case #1 to IAB-DU Rx in timing Case #7;
Switching from IAB-DU Rx in timing Case #1 to IAB-MT Tx in timing Case #6;
Switching from IAB-DU Rx in timing Case #1 to IAB-MT Rx in timing Case #7;
Switching from IAB-DU Tx in timing Case #1 to IAB-MT Tx in timing Case #6;
Switching from IAB-DU Tx in timing Case #1 to IAB-MT Rx in timing Case #7;
a third timing switching group comprising one or more of the following timing alignment cases:
Switching from IAB-MT Rx in timing Case #7 to IAB-DU Tx in timing Case #1;
Switching from IAB-MT Rx in timing Case #7 to IAB-DU Rx in timing Case #1;
Switching from IAB-MT Tx in timing Case #6 to IAB-DU Tx in timing Case #1;
Switching from IAB-MT Tx in timing Case #6 to IAB-DU Rx in timing Case #1;
Switching from IAB-DU Rx in timing Case #7 to IAB-MT Tx in timing Case #1;
Switching from IAB-DU Rx in timing Case #7 to IAB-MT Rx in timing Case #1;
Switching from IAB-DU Tx in timing Case #6 to IAB-MT Tx in timing Case #1;
Switching from IAB-DU Tx in timing Case #6 to IAB-MT Rx in timing Case #1;
a fourth timing switching group comprising one or more of the following timing alignment cases:
Switching from IAB-MT Rx in timing Case #7 to IAB-DU Tx in timing Case #6;
Switching from IAB-MT Rx in timing Case #7 to IAB-DU Rx in timing Case #7;
Switching from IAB-MT Tx in timing Case #6 to IAB-DU Tx in timing Case #6;
Switching from IAB-MT Tx in timing Case #6 to IAB-DU Rx in timing Case #7;
Switching from IAB-DU Rx in timing Case #7 to IAB-MT Tx in timing Case #6;
Switching from IAB-DU Rx in timing Case #7 to IAB-MT Rx in timing Case #7;
Switching from IAB-DU Tx in timing Case #6 to IAB-MT Tx in timing Case #6;
Switching from IAB-DU Tx in timing Case #6 to IAB-MT Rx in timing Case #7.
6 . The method of claim 1 , wherein sending the one or more sets of desired numbers of guard symbols for two or more timing switching groups, respectively, to the parent IAB node comprises sending the one or more sets of desired numbers of guard symbols for two or more timing switching groups, respectively, to the parent IAB node via one or more Medium Access Control Control Elements, MAC CEs.
7 . The method of claim 6 wherein each MAC CE of the one or more MAC CEs comprises one or more of sub-carrier spacing, SCS, bits to indicate that the one or more sets of desired numbers of guard symbols correspond to one or more of Group-2, Group-3, or Group-4, respectively.
8 . The method of claim 1 , wherein receiving the one or more sets of provided numbers of guard symbols for the two or more timing switching groups, respectively, comprises receiving the one or more sets of provided numbers of guard symbols for the two or more timing switching groups, respectively, from the parent IAB node via one or more Medium Access Control Control Elements, MAC CEs.
9 . The method of claim 8 wherein each MAC CE of the one or more MAC CEs comprises one or more bits that indicate one of the two or more timing switching groups for which the MAC CE contains the respective set of provided numbers of guard symbols.
10 . An Integrated Access and Backhaul, IAB, node, adapted to:
send, to a parent IAB node, one or more sets of desired numbers of guard symbols for two or more timing switching groups, respectively, wherein:
each timing switching group of the two or more timing switching groups comprises one or more timing alignment cases; and
each set of desired numbers of guard symbols comprises a desired number of guard symbols for the one or more timing alignment cases comprised in the respective timing switching group of the two or more timing switching groups;
receive, from the parent IAB node, one or more sets of provided numbers of guard symbols for the two or more timing switching groups, respectively; and
determine available time resources for one or more of: uplink transmission and downlink reception in two adjacent time units based on one of the one or more sets of provided numbers of guard symbols for one of the two or more timing switching groups that corresponds to timing alignment cases used in the two adjacent time units.
11 . A method performed by a parent Integrated Access and Backhaul, IAB, node, comprising:
receiving, from a IAB node, one or more sets of desired numbers of guard symbols for two or more timing switching groups, respectively, wherein:
each timing switching group of the two or more timing switching groups comprises one or more timing alignment cases; and
each set of desired numbers of guard symbols comprises a desired number of guard symbols for the one or more timing alignment cases comprised in the respective timing switching group of the two or more timing switching groups;
sending, to the IAB node, one or more sets of provided numbers of guard symbols for the two or more timing switching groups, respectively;
determining available time resources for one or more of: uplink transmission and downlink reception in two adjacent time units based on one of the one or more sets of provided numbers of guard symbols for one of the two or more timing switching groups that corresponds to timing alignment cases used in the two adjacent time units.
12 . The method of claim 11 , wherein:
the IAB node comprises an IAB-Mobility Termination, IAB-MT, and an IAB-Distributed Unit, IAB-DU, and
the desired numbers of guard symbols are numbers of symbols that the IAB-MT indicates to the parent IAB node not to use for the IAB-MT in slots where the IAB node transitions between the IAB-MT and the IAB-DU.
13 . The method of claim 11 , wherein:
the IAB node comprises an IAB-Mobility Termination, IAB-MT, and an IAB-Distributed Unit, IAB-DU, and
the provided numbers of guard symbols are numbers of symbols that are not be used for the IAB-MT in slots where the IAB node transitions between the IAB-MT and the IAB-DU.
14 . The method of claim 11 further comprising performing one or more of: uplink transmission and downlink reception in the two adjacent time units based on the determined available time resources.
15 . The method of claim 11 , wherein the two or more timing switching groups comprise one or more of the following:
a first timing switching group comprising one or more of the following timing alignment cases:
Switching from IAB-MT Rx in timing Case #1 to IAB-DU Tx in timing Case #1;
Switching from IAB-MT Rx in timing Case #1 to IAB-DU Rx in timing Case #1;
Switching from IAB-MT Tx in timing Case #1 to IAB-DU Tx in timing Case #1;
Switching from IAB-MT Tx in timing Case #1 to IAB-DU Rx in timing Case #1;
Switching from IAB-DU Rx in timing Case #1 to IAB-MT Tx in timing Case #1;
Switching from IAB-DU Rx in timing Case #1 to IAB-MT Rx in timing Case #1;
Switching from IAB-DU Tx in timing Case #1 to IAB-MT Tx in timing Case #1;
Switching from IAB-DU Tx in timing Case #1 to IAB-MT Rx in timing Case #1;
a second timing switching group comprising one or more of the following timing alignment cases:
Switching from IAB-MT Rx in timing Case #1 to IAB-DU Tx in timing Case #6;
Switching from IAB-MT Rx in timing Case #1 to IAB-DU Rx in timing Case #7;
Switching from IAB-MT Tx in timing Case #1 to IAB-DU Tx in timing Case #6;
Switching from IAB-MT Tx in timing Case #1 to IAB-DU Rx in timing Case #7;
Switching from IAB-DU Rx in timing Case #1 to IAB-MT Tx in timing Case #6;
Switching from IAB-DU Rx in timing Case #1 to IAB-MT Rx in timing Case #7;
Switching from IAB-DU Tx in timing Case #1 to IAB-MT Tx in timing Case #6;
Switching from IAB-DU Tx in timing Case #1 to IAB-MT Rx in timing Case #7;
a third timing switching group comprising one or more of the following timing alignment cases:
Switching from IAB-MT Rx in timing Case #7 to IAB-DU Tx in timing Case #1;
Switching from IAB-MT Rx in timing Case #7 to IAB-DU Rx in timing Case #1;
Switching from IAB-MT Tx in timing Case #6 to IAB-DU Tx in timing Case #1;
Switching from IAB-MT Tx in timing Case #6 to IAB-DU Rx in timing Case #1;
Switching from IAB-DU Rx in timing Case #7 to IAB-MT Tx in timing Case #1;
Switching from IAB-DU Rx in timing Case #7 to IAB-MT Rx in timing Case #1;
Switching from IAB-DU Tx in timing Case #6 to IAB-MT Tx in timing Case #1;
Switching from IAB-DU Tx in timing Case #6 to IAB-MT Rx in timing Case #1;
a fourth timing switching group comprising one or more of the following timing alignment cases:
Switching from IAB-MT Rx in timing Case #7 to IAB-DU Tx in timing Case #6;
Switching from IAB-MT Rx in timing Case #7 to IAB-DU Rx in timing Case #7;
Switching from IAB-MT Tx in timing Case #6 to IAB-DU Tx in timing Case #6;
Switching from IAB-MT Tx in timing Case #6 to IAB-DU Rx in timing Case #7;
Switching from IAB-DU Rx in timing Case #7 to IAB-MT Tx in timing Case #6;
Switching from IAB-DU Rx in timing Case #7 to IAB-MT Rx in timing Case #7;
Switching from IAB-DU Tx in timing Case #6 to IAB-MT Tx in timing Case #6;
Switching from IAB-DU Tx in timing Case #6 to IAB-MT Rx in timing Case #7.
16 . The method of claim 11 , wherein receiving the one or more sets of desired numbers of guard symbols for two or more timing switching groups, respectively, from the IAB node comprises receiving the one or more sets of desired numbers of guard symbols for two or more timing switching groups, respectively, from the IAB node via one or more Medium Access Control Control Elements, MAC CEs.
17 . The method of claim 16 wherein each MAC CE of the one or more MAC CEs comprises one or more of sub-carrier spacing, SCS, bits to indicate that the one or more sets of desired numbers of guard symbols correspond to one or more of Group-2, Group-3, or Group-4, respectively.
18 . The method of claim 11 , wherein sending the one or more sets of provided numbers of guard symbols for the two or more timing switching groups, respectively, comprises sending the one or more sets of provided numbers of guard symbols for the two or more timing switching groups, respectively, to the IAB node via one or more MAC CEs.
19 . The method of claim 18 wherein each MAC CE of the one or more MAC CEs comprises one or more bits that indicate one of the two or more timing switching groups for which the MAC CE contains the respective set of provided numbers of guard symbols.
20 . A parent Integrated Access and Backhaul, IAB, node, adapted to:
receive, from a IAB node, one or more sets of desired numbers of guard symbols for two or more timing switching groups, respectively, wherein:
each timing switching group of the two or more timing switching groups comprises one or more timing alignment cases; and
each set of desired numbers of guard symbols comprises a desired number of guard symbols for the one or more timing alignment cases comprised in the respective timing switching group of the two or more timing switching groups;
send, to the IAB node, one or more sets of provided numbers of guard symbols for the two or more timing switching groups, respectively;
determine available time resources for one or more of: uplink transmission and downlink reception in two adjacent time units based on one of the one or more sets of provided numbers of guard symbols for one of the two or more timing switching groups that corresponds to timing alignment cases used in the two adjacent time units.