US-12628147-B2 - Method for locating DC carrier

US12628147B2US 12628147 B2US12628147 B2US 12628147B2US-12628147-B2

Abstract

An apparatus comprising: means for determining one or more uplink direct current (DC) carriers needed for a radio band combination (BC); means for determining locations of each DC carrier of the radio band combination, wherein said means comprise means for determining a location of at least one DC carrier of the radio band combination according to locations of bandwidth part (BWP) carriers; means for including an indicator about the location of the at least one DC carrier in an extended DC location reporting in a UE capability indication; and means for signalling indicators about the determined location of each DC carrier in a UE capability indication.

Inventors

Hiromasa Umeda
Petri Juhani Vasenkari
Tero Henttonen

Assignees

NOKIA TECHNOLOGIES OY

Dates

Publication Date: 20260512
Application Date: 20201026

Claims (13)

1 . An apparatus comprising at least one processor and at least one memory, said at least one memory stored with computer program code thereon, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: determine one or more uplink direct current carriers needed for a radio band combination; determine locations of each direct current carrier of the radio band combination, wherein a location of at least one direct current carrier of the radio band combination is determined according to locations of bandwidth part carriers and/or component carriers, wherein for said at least one direct current carrier, the location of the direct current carrier is determined based on one of the following: a center of a lower edge of the lowest active bandwidth part and a higher edge of the highest active bandwidth part among all active component carriers in the radio band combination; or a center of a lower edge of the lowest component carrier and a higher edge of the highest component carrier among all active component carriers in the radio band combination; include an indicator about the location of the at least one direct current carrier in a direct current location reporting field; and signal at least said indicator.
2 . The apparatus according to claim 1 , wherein the at least one memory and the computer program code configured to, with the at least one processor, further cause the apparatus at least to: determine, in response to at least one of lowest and highest component carriers lacks an active bandwidth part, to replace the lacking bandwidth part by a corresponding component carrier for the determination of the location of the direct current carrier.
3 . The apparatus according to claim 1 , wherein the at least one memory and the computer program code configured to, with the at least one processor, further cause the apparatus at least to: determine whether the radio band combination used by the apparatus comprises at least one group of a plurality of component carriers; and determine, in response to at least one group of only one component carrier is included in the radio band combination, that the location of the direct current per CC is a direct current location of a bandwidth part of said component carrier.
4 . The apparatus according to claim 1 , wherein the at least one memory and the computer program code configured to, with the at least one processor, further cause the apparatus at least to: determine, in response to at least one group of a plurality of component carriers is included in the radio band combination, that one location of the direct current carrier per a group of a plurality of component carriers is defined; and determine the location of the direct current carrier as the center of the lower edge of the lowest active bandwidth part and the higher edge of the highest active bandwidth part among all active component carriers in the radio band combination used by the apparatus.
5 . The apparatus according to claim 1 , wherein the at least one memory and the computer program code configured to, with the at least one processor, further cause the apparatus at least to: indicate support for extended direct current location reporting in a user equipment capability indication.
6 . The apparatus according to claim 1 , wherein the at least one memory and the computer program code configured to, with the at least one processor, further cause the apparatus at least to: indicate whether the direct current locations are using single power amplifier or dual power amplifier architecture in a user equipment capability indication.
7 . A method comprising: determining, by an apparatus, one or more uplink direct current carriers needed for a radio band combination; determining locations of each direct current carrier of the radio band combination, wherein a location of at least one direct current carrier of the radio band combination is determined according to locations of bandwidth part carriers and/or component carriers, wherein for said at least one direct current carrier, the location of the direct current carrier is determined based on one of the following: a center of a lower edge of the lowest active bandwidth part and a higher edge of the highest active bandwidth part among all active component carriers in the radio band combination; or a center of a lower edge of the lowest component carrier and a higher edge of the highest component carrier among all active component carriers in the radio band combination; including an indicator about the location of the at least one direct current carrier in a direct current location reporting field; and signalling at least said indicator.
8 . The method according to claim 7 , comprising: determining, in response to at least one of lowest and highest component carriers lacks an active bandwidth part, to replace the lacking bandwidth part by a corresponding component carrier for the determination of the location of the direct current carrier.
9 . The method according to claim 7 , comprising: determining whether the radio band combination used by the apparatus comprises at least one group of a plurality of component carriers; and determining, in response to at least one group of only one component carrier is included in the radio band combination, that the location of the direct current per component carrier is a direct current location of a bandwidth part of said component carrier.
10 . The method according to claim 7 , comprising: determining, in response to at least one group of a plurality of component carriers is included in the radio band combination, that one location of the direct current carrier per a group of a plurality of component carriers is defined; and determining the location of the direct current carrier as the center of the lower edge of the lowest active bandwidth part and the higher edge of the highest active bandwidth part among all active component carriers in the radio band combination used by the apparatus.
11 . The method according to claim 7 , comprising: indicating support for extended direct current location reporting in a user equipment capability indication.
12 . The method according to claim 7 , comprising: indicating whether the direct current locations are using single power amplifier or dual power amplifier architecture in a user equipment capability indication.
13 . An apparatus comprising at least one processor and at least one memory, said at least one memory stored with computer program code thereon, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: determine one or more uplink direct current carriers needed for a radio band combination; determine locations of each direct current carrier of the radio band combination, wherein a location of at least one direct current carrier of the radio band combination is determined according to one of the following: the location of the direct current carrier as a center of a lower edge of the lowest active bandwidth part and a higher edge of the highest active bandwidth part among all active component carriers in the radio band combination; or the location of the direct current carrier as a center of a lower edge of the lowest component carrier and a higher edge of the highest component carrier among all active component carriers in the radio band combination; and use the determined location of the direct current carrier for uplink transmission.

Description

TECHNICAL FIELD The present invention relates to DC carrier locating operations. BACKGROUND One new concept in 5G NR (New Radio) networks is a feature known as bandwidth parts (BWPs). BWPs enable more flexibility in assigning multiple, different signal types to be sent in a given bandwidth. While the 5G base stations typically can utilize the wider bandwidths, the user equipment (UE) capabilities will vary and not all UEs will be capable to use the larger available bandwidths. BWPs enable multiplexing of different signals and signal types for better utilization and adaptation of spectrum and UE power. A UE will always have at least one uplink (UL) BWP and one downlink (DL) BWP configured for each serving cell, and at least one such BWP will be active for both UL and DL. The UL Direct Current (DC) subcarrier in OFDM is a subcarrier that is not usable for data transmission. As the DC carrier location may vary depending on which UL BWP is used, the UE is required to indicate to the network what is the DC location of each BWP for a single-carrier case. However, as defined in 3GPP Release 15, the UE is not required to report a certain location, such as a center frequency, for any UL BWP but the UE has various options: It may report the center frequency of each UL BWP, but it may also simply choose to indicate the same DC carrier for all UL BWPs. The UE may even indicate the DC carrier location to the network as “outside carrier” or “unknown”. The above arrangement works well with a single-carrier case without any uplink (UL) carrier aggregation (CA). However, for intra-band UL CA, it may not be sufficient as the UE may use either a single power amplifier (PA) or multiple PA architecture (e.g., dual-PA architecture), in which case the DC location for each carrier or multiple carriers which one PA (or each one of the PAs) covers may again change depending on the combination of UL BWPs chosen in each serving cell. SUMMARY Now, an improved method and technical equipment implementing the method has been invented, by which the above problems are alleviated. Various aspects include a method, an apparatus and a non-transitory computer readable medium comprising a computer program, or a signal stored therein, which are characterized by what is stated in the independent claims. Various details of the embodiments are disclosed in the dependent claims and in the corresponding images and description. The scope of protection sought for various embodiments of the invention is set out by the independent claims. The embodiments and features, if any, described in this specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various embodiments of the invention. According to a first aspect, there is provided an apparatus comprising means for obtaining, from a user equipment (UE), a UE capability indication about one or more uplink direct current (DC) carriers needed by a radio band combination (BC) used by the UE; means for determining, from the UE capability indication whether the UE supports extended DC location reporting; means for determining, in accordance with the support or non-support of extended DC location reporting in UE capability indication, whether a location of at least one DC carrier is to be determined as a default location or according to locations of bandwidth part (BWP) carriers and/or component carriers (CC) in response to detecting an indicator about the location of at least one DC carrier in an extended DC location reporting field in the UE capability indication; and means for using the determined location of the DC carrier for uplink reception. According to an embodiment, the apparatus comprises means for determining, in response to the UE supporting extended DC location reporting, location of the DC carrier as a center of a lower edge of the lowest active bandwidth part (BWP) and a higher edge of the highest active BWP among all active component carriers (CC) in the radio band combination used by the UE; and means for determining, in response to the UE not supporting extended DC location reporting, location of the DC carrier as a center of a lower edge of the lowest component carrier (CC) and a higher edge of the highest component carrier (CC) among all active component carriers (CC) in the radio band combination used by the UE. According to an embodiment, the apparatus comprises means for determining, in response to the UE supporting extended DC location reporting and at least one of lowest and highest CCs lacks an active BWP, to replace the lacking BWP by a corresponding CC for the determination of the location of the DC carrier. According to an embodiment, the apparatus comprises means for determining, in response to the radio band combination used by the UE needing more than one DC carrier, whether the radio band combination (BC) used by the UE comprises at least one group of consisting of one component carrier (CC); and means f