21 Eight Carrier HSDPA Operation (FDD only)
25.3083GPPHigh Speed Downlink Packet Access (HSDPA)Overall descriptionRelease 17Stage 2TS
Eight Carrier HSDPA operation is characterized as simultaneous reception of up to eight HS-DSCH transport channels. Certain categories of UEs may be configured with Eight Carrier HSDPA operation with or without MIMO in CELL_DCH state. Eight Carrier HSDPA operation may be activated and deactivated using HS-SCCH orders transmitted from the serving Node-B.
When the UE is configured with Eight Carrier HSDPA operation, a common transmitting MAC-ehs entity is used for data transmission, and the HS-DSCH channels shall be operated in the following manner:
– The transmitting and receiving MAC-ehs entity support up to eight HS-DSCH transport channels.
– Each of these HS-DSCH transport channels has its own associated uplink and downlink signalling, and own HARQ entity (further composed of multiple HARQ processes).
– Reordering, duplicate detection, segmentation and reassembly functions are joint for these HS-DSCH transport channels and HARQ entities.
When the UE is configured with Eight Carrier HSDPA operation:
– There is one serving HS-DSCH cell and up to seven secondary serving HS-DSCH cells.
– The TSN field in the MAC-ehs header is extended to 14 contiguous bits.
– The mobility procedures, as defined in section 9, are supported based on the serving HS-DSCH cell. A serving cell change similar to the one shown in Figure 18-1 is possible for Eight Carrier HSDPA operation.
– The DRX status is common for all serving HS-DSCH cells. The DRX activation and deactivation is possible with HS-SCCH orders.
– HS-SCCH-less operation is restricted to the serving HS-DSCH cell.
– Transmit diversity is configurable per downlink frequency.
– Certain categories of UEs may be configured to operate in MIMO mode per serving HS-DSCH cell, as follows:
– MIMO operation per serving HS-DSCH cell is performed as per section 13.
– CQI reports related to all activated serving HS-DSCH cells are transmitted
– The maximum number of MAC-ehs PDUs per TTI is 16, when eight serving HS-DSCH cells configured with MIMO operation are active.
– Certain categories of UEs may be configured to operate in multiple radio frequencies as follows:
– The UE is configured with up to eight HS-DSCH transport channels which are carried over 1 or 2 radio frequency bands.
– The downlink frequencies within a single frequency band are configured adjacent. Non-adjacent operation of downlink frequencies due to the deactivation of the configured downlink frequencies within a single frequency band may take place.
– If more than three secondary serving HS-DSCH cells are configured then two HS-DPCCH codes are used to carry feedback information (ACK/NACK, CQI and precoding control information) related to the HS-DSCH transport channels. The HS-DPCCH1 carries feedback information associated with the serving HS-DSCH cell and the 1st, 2nd, and 3rd secondary serving HS-DSCH cells. The HS-DPCCH2 carries feedback information associated with the 4th, 5th, 6th, and 7th secondary serving HS-DSCH cells.
– Eight Carrier HSDPA operation may be configured with Dual Cell E-DCH operation, as described in [3]. DCH is supported if the UE has only one Configured Uplink frequency.
– Synchronization and RLF:
– For physical channel establishment for the downlink frequencies associated with an Activated Uplink Frequency, the rules as specified for Dual Cell E-DCH operation are applied.
– Physical channel establishment is not performed for the downlink frequencies not associated with an Activated Uplink Frequency.
– RLF is based on the primary downlink frequency.
– Measurements:
– If only one uplink frequency is configured, the UE performs intra-frequency measurement only on the primary downlink frequency.
– If two uplink frequencies are configured, the UE performs intra-frequency measurement on the corresponding primary downlink frequency and secondary downlink frequency.