Section: – FeatureSetCombination
Content: The IE FeatureSetCombination is a two-dimensional matrix of FeatureSet entries. Each FeatureSetsPerBand contains a list of feature sets applicable to the carrier(s) of one band entry of the associated band combination. Across the associated bands, the UE shall support the combination of FeatureSets at the same position in the FeatureSetsPerBand. All FeatureSetsPerBand in one FeatureSetCombination must have the same number of entries. The number of FeatureSetsPerBand in the FeatureSetCombination must be equal to the number of band entries in an associated band combination. The first FeatureSetPerBand applies to the first band entry of the band combination, and so on. Each FeatureSet contains either a pair of NR or E-UTRA feature set IDs for UL and DL. In case of NR, the actual feature sets for UL and DL are defined in the FeatureSets IE and referred to from here by their ID, i.e., their position in the featureSetsUplink / featureSetsDownlink list in the FeatureSet IE. In case of E-UTRA, the feature sets referred to from this list are defined in TS 36.331[ Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification ]  [10] and conveyed as part of the UE-EUTRA-Capability container. The FeatureSetUplink and FeatureSetDownlink referred to from the FeatureSet comprise, among other information, a set of FeatureSetUplinkPerCC-Ids and FeatureSetDownlinkPerCC-Ids. The number of these per-CC IDs determines the number of carriers that the UE is able to aggregate contiguously in frequency domain in the corresponding band. The number of carriers supported by the UE is also restricted by the bandwidth class indicated in the associated BandCombination, if present. In feature set combinations the UE shall exclude entries with same or lower capabilities, since the network may anyway assume that the UE supports those. NOTE 1: The UE may advertise fallback band-combinations in which it supports additional functionality explicitly in two ways: Either by setting FeatureSet IDs to zero (inter-band and intra-band non-contiguous fallback) and by reducing the number of FeatureSet-PerCC Ids in a Feature Set (intra-band contiguous fallback). Or by separate BandCombination entries with associated FeatureSetCombinations. NOTE 2: The UE may advertise a FeatureSetCombination containing only fallback band combinations. That means, in a FeatureSetCombination, each group of FeatureSets across the bands may contain at least one pair of FeatureSetUplinkId and FeatureSetDownlinkId which is set to 0/0. NOTE 3: The Network configures serving cell(s) and BWP(s) configuration to comply with capabilities derived from the combination of FeatureSets at the same position in the FeatureSetsPerBand, regardless of activated/deactivated serving cell(s) and BWP(s). FeatureSetCombination information element -- ASN1START -- TAG-FEATURESETCOMBINATION-START FeatureSetCombination ::= SEQUENCE (SIZE (1..maxSimultaneousBands)) OF FeatureSetsPerBand FeatureSetsPerBand ::= SEQUENCE (SIZE (1..maxFeatureSetsPerBand)) OF FeatureSet FeatureSet ::= CHOICE { eutra SEQUENCE { downlinkSetEUTRA FeatureSetEUTRA-DownlinkId, uplinkSetEUTRA FeatureSetEUTRA-UplinkId }, nr SEQUENCE { downlinkSetNR FeatureSetDownlinkId, uplinkSetNR FeatureSetUplinkId } } -- TAG-FEATURESETCOMBINATION-STOP -- ASN1STOP