Short identifiers for device-to-device (D2D) broadcast communications
Methods, apparatuses, systems, and computer program products for transmitting/receiving scheduling assignment(s) (SAs) are provided. One method is directed to including a short version of a target ID (i.e., short ID) in a SA. The method may also include transmitting the SA including the short ID to one or more monitoring UE(s). The monitoring UE(s) may then compare the short ID to target ID(s) being monitored. The corresponding data from the SA may be decoded if there is a match between the short ID and any of the target ID(s).
1. An apparatus, comprising:
at least one processor; and
at least one memory including computer program code,
the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus at least to
generate a short identifier by taking bits from any pre-defined position of a layer-2 target identifier;
include the short identifier comprising a short version of the layer-2 target identifier in a scheduling assignment;
transmit the scheduling assignment comprising the short identifier; and
include in a data transmission, corresponding to the scheduling assignment, information on layer-2 target identifier determination;
wherein the layer-2 target identifier is included to be used to uniquely identify a target receiving user equipment (UE) or a target receiving user equipment (UE) group which the data transmission is meant for,
wherein the short identifier is included to be used at the target receiving user equipment (UE) to determine, by comparing with the layer-2 target identifier, if the target receiving user equipment (UE) needs to decode the corresponding data transmission to obtain information for determining the layer-2 target identifier of the data transmission.
2. The apparatus according to claim 1 , wherein the at least one memory and the computer program code are further configured, with the at least one processor, to cause the apparatus at least to generate the short identifier by following a preconfigured mapping table connecting target identifiers to short identifiers.
3. The apparatus according to claim 1 , wherein the layer-2 target identifier comprises a layer-2 identifier of the target user equipment or the target user equipment (UE) group.
4. The apparatus according to claim 1 , wherein the apparatus comprises a device-to-device (D2D) user equipment.
5. The apparatus according to claim 1 , wherein the at least one memory and the computer program code are further configured, with the at least one processor, to cause the apparatus at least to generate the short identifier by taking the 5 least significant bits of the target identifier.
6. A method, comprising:
generating a short identifier by taking bits from any pre-defined position of a layer-2 target identifier;
including, by a user equipment, the short identifier comprising a short version of the layer-2 target identifier in a scheduling assignment;
transmitting the scheduling assignment comprising the short identifier; and
including in a data transmission, corresponding to the scheduling assignment, information on layer-2 target identifier determination,
wherein the layer-2 target identifier is included to be used to uniquely identify a target receiving user equipment (UE) or a target receiving user equipment (UE) group which the data transmission is meant for,
wherein the short identifier is included to be used at the target receiving user equipment (UE) to determine, by comparing with the layer-2 target identifier, if the target receiving user equipment (UE) needs to decode the corresponding data transmission to obtain information for determining the layer-2 target identifier of the data transmission.
7. The method according to claim 6 , further comprising generating the short identifier by following a preconfigured mapping table connecting target identifiers to short identifiers.
8. The method according to claim 6 , wherein the layer-2 target identifier comprises a layer-2 identifier of the target user equipment or the target receiving user equipment (UE) group.
9. The method according to claim 6 , further comprising generating the short identifier by taking the 5 least significant bits of the target identifier.
10. An apparatus, comprising:
at least one processor; and
at least one memory including computer program code,
the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus at least to
receive a scheduling assignment from a transmitting user equipment, wherein the scheduling assignment comprises a short identifier that represents a short version of a layer-2 target identifier; and
identify the short identifier from the scheduling assignment,
wherein the short identifier is generated by taking bits from any pre-defined position of the layer-2 target identifier; and
receive, in a data transmission, corresponding to the scheduling assignment, information for determining layer-2 target identity of the data transmission,
wherein the layer-2 target identifier is received to be used to uniquely identify transmissions that are meant for the apparatus,.
wherein the short identifier is received to be used at the apparatus to determine, by comparing with the layer-2 target identifier, if the apparatus needs to decode the corresponding data transmission to obtain information for determining the layer-2 target identifier of the data transmission.
11. The apparatus according to claim 10 , wherein the at least one memory and the computer program code are further configured, with the at least one processor, to cause the apparatus at least to compare the short identifier to short identifiers corresponding to target identifiers being monitored by the apparatus.
12. The apparatus according to claim 10 , wherein the at least one memory and the computer program code are further configured, with the at least one processor, to cause the apparatus at least to decode a data transmission corresponding to the scheduling assignment with the short identifier that matches a target identifier being monitored by the apparatus.
13. The apparatus according to claim 10 , wherein the apparatus comprises a device-to-device (D2D) user equipment.
14. A method, comprising:
receiving, by a user equipment, a scheduling assignment from a transmitting user equipment, wherein the scheduling assignment comprises a short identifier that represents a short version of a layer-2 target identifier;
identifying the short identifier from the received scheduling assignment,
wherein the short identifier is generated by taking bits from any pre-defined position of the layer-2 target identifier; and
receiving, in a data transmission, corresponding to the scheduling assignment, information for determining layer-2 target identity of the data transmission,
wherein the layer-2 target identifier is received to be used to uniquely identify transmissions that are meant for the user equipment,.
wherein the short identifier is received to be used at the user equipment to determine, by comparing with the layer-2 target identifier, if the user equipment needs to decode the corresponding data transmission to obtain information for determining the layer-2 target identifier of the data transmission.
15. The method according to claim 14 , further comprising comparing the short identifier to short identifiers corresponding to target identifiers being monitored by the user equipment.
16. The method according to claim 15 , further comprising decoding a data transmission corresponding to the scheduling assignment with the short identifier that matches a target identifier being monitored by the user equipment.
17. An apparatus, comprising:
at least one processor; and
at least one memory including computer program code,
the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus at least to
select a first layer-2 identifier of a user equipment group of a first length;
create a second identifier of a second length that is shorter than the first length from the first layer-2 identifier,
wherein the second identifier is composed from certain bits of the first layer-2 identifier;
transmit the second identifier in a scheduling assignment message; and
transmit, in resources to be used for data transmission, information on the first layer-2 identifier,
wherein the first layer-2 identifier is configured to be used to uniquely identify transmissions that are meant for target receiving user equipment (UEs),
wherein the second identifier is transmitted to be used at the target receiving user equipment (UE) to determine, by comparing with the first layer-2 identifier, if the target receiving user equipment (UE) needs to decode the corresponding data transmission to obtain information for determining the first layer-2 identifier of the data transmission.
18. The apparatus according to claim 17 , wherein the at least one memory and the computer program code are further configured, with the at least one processor, to cause the apparatus at least to:
apply a mapping table that has been configured or signaled beforehand for the user equipment.
19. The apparatus according to claim 17 , wherein the first identifier comprises a target identifier.