It can be thought of as a major concern of the key technology in the evolution to LTE-Advanced can be considered as CA (Carrier Aggregation). Earlier stage of evolution, some operators are to CA is MC (Multi rainbow trout Carrier) immediately before rainbow trout that step and proceed. MC may have additional frequency with priority and has the advantage of the traffic off-load. These additional Carrier and LTE-A in combination with a maximum of CA DL 3Gbps UL 1.5Gbps (8 by 8 MIMO, 64QAM FDD BandWidth 100Mhz etc.), And the speed can be implemented, DL, UL everyone up to 5CC (up to 100Mhz) to can be added. However, if the form of the CA Rel.11 is a method commonly used in inter-band non-contiguous because of Harmonics and Intermoduation 2DL, 1UL support rainbow trout only. The only Rel.12 SKT 2DL, the state proposed a 2UL. Service CA is configured, the existing terminals such as traditional Rel.8 / 9, that is, even the existing user at the same time there is a Carrier of various types and the like in consideration backward carrier and overhead reduction and heterogenous network environment that receive the service.
CA configured at Cell (a CA) are largely made up of two to PCell (Primary Cell) and SCell (Secondary Cell). PCell when PCC (Primary Componet Carrier) to belong, rainbow trout RRC connection establishment / re-establishing, measuring, mobility rainbow trout procedures, random access procedures and selection, system information rainbow trout acquisition, initial random access, security key changes and Non-Access Stratum (NAS) functionality provides. PCell can not be disabled, because it is never done to monitor system information as Rel.8, in the UL PCC is carried in PUCCH for transmitting Control Information. Also only be one of the only connection RRC, PDCCH / PDSCH / PUSCH / PUCCH transmission is possible.
SCell can be added up to a maximum total of four, and if the radio provides the necessary additional resources are only acquired through the RRC Connection Reconfiguration message dedicated signaling a message made. The message includes a physical cell ID of each cell to be sent and, DL Carrier Frequency (Absolute radio Frequency Channel Nmuber) ARFCN to be included. SCell the PDCCH / PDSCH / PUSCH transmission rainbow trout is possible and, PUCCH is impossible. The MAC layer of the UE to the battery conservation supports dynamic active, inactive procedures SCell.
CIF and Cross-carrier Scheduling was introduced to the activity of the ICIC in Heterogeneous Network. For one scenario, the CC (Componet Carrier) in the case of allocating all of the L1 / L2 control channel such as the PDCCH in one CC. This interference of the control channel in the case of writing the same frequency HeNet (eg. Macro cell and interference caused by the use of a femto cell), rainbow trout because this may cause. If the data channel is not a problem because a user places the propagation delay (propogation delay) would look like if the receive data is turned on at the same time, when the same broadcast control channel because it can cause interference. rainbow trout Therefore, this scheme uses the MC (multi carrier), or to reduce the ABS (Almost rainbow trout Blank Subframe) and the interference with the use of Cross-Carrier is to reduce the interference.
Applying a DCI format of the Cross-Scheduling are added 3bit CIF, the size of the bit is always fixed, DCI Format size, regardless of the position is also fixed. Reuse of Rel.8 PDCCH structure for defense after such compatibility with existing Rel.8 / 9 (same code, the same CCE-based resource mapping, etc.) is possible. Further DCI format 0, 1, 1A, 1B, 1D, 2, 2A, a UE cross-carrier scheduling of the particular search space 2B from shall be always supported by explicitly CIF.
To address the increasing cross-carrer scheduling and scheduling blocking probability and dimension rainbow trout limits, LTE Rel.8 search space design has been extended for the CC carries cross carrier control signaling. In the UE, the location of the search space PDCCH CC are defined individually per integrated level for each PDSCH / PUSCH CC which is linked to the PDCCH CC, the search rainbow trout space of the UE in the PDCCH CC is shared in case of the same size DIC.
To support the cross-carrier control signaling in order to simplify the search space expansion, the introduction of each additional CC may be offset. The picture in Figure 1 is shown in CCm carrying the PDCCH signaling for CCj and CCk. Start for CC m CCE index is based is derived from LTE Rel.8. Starting CCE index for all CCs are specified through a portion offset as compared to CC m. The offset may be a random or hard-coding the layer 3 is configured.
In principle, if the cross-carrier scheduling approach for UE specific SS There are two design per CC. One single Rel.8 hash (hash) works based on SS UE specific configuration per CC. The method starts CCE index of the UE for a particular SS referent rainbow trout lances CC is configured by the Rel.8 hash function, SS of the other CC is in the PDCCH CC can be configured in a variety of ways. The CC is the referent lances can be one of the self-scheduling or scheduling CC.
Method with a continuous (consecutive) UE specific SS, offset based UE specific SS, SS interlaced UE specific configuration, Sparse interlaced UE specific SS configuration, and the like. Interlace look at the specific UE SS configuration, the method may be distributed through the CC by the SS on multiple interlaces CC of one or several PDCCH list, PDCCH blocking For SS overlaped. rainbow trout In addition, it is possible to re-use the formula rainbow trout for the UE-specific rainbow trout hashing Rel.8 SS starting CCE index calculation. Rel.8 UE specific SS construction with cross-carrier scheduling, but can vary in the PDCCH list for each CC. Interlaced SS construction itda the benefit does not affect Rel.8 UE and Rel.10 UE PDCCH decoding in single-carrier capability.
Support for explicit signaling to perform flexible cross-carrier scheduling is the gain. However, if a defect signal of the explicit signaling rainbow trout is added which leads to an overhead. 3 bit CI's for making the CIF Joint Coding and Control Format Indicator (CFI) is effective to avoid an additional signal because there is a bit that is not used in the actual CIF.
RRC signaling is used to transmit the CFI value to the UE. The table "CCn" (n = 0, 1, 2, 3, 4) are shifted PDSCH is mapped to the index at which the CC represents the value. In addition, unless the "CFI = N" is between CFI CFI carrier scheduling and displays a value that is transmitted through the RRC signaling. In order to avoid the errors of the number of CFI values that change in CC available from the table, CC can be set as the number of continuous estimation of the CFI value is changed from the maximum range.
Figure shows an example of when the available number of CC 2, the component carrier index 0 is displayed, when the CIF 000 (subject to the CFI PCFICH in CC0, cross-carrier scheduling is not applied.) And CIF 001 is displayed CFI is a component carrier index 1 and a value of 1. In addition, Figure 1 (b) shows another example of a possible when the number of CC 4, 000 CIF display component carrier index 0 (subject to the CFI in CC0 PCFICH, cross-carrier scheduling is not applied.) And a 111 CFI The component carrier index CFI value N = 3 and is controlled by a quasi-static control rainbow trout by the RRC signaling.
To overcome the defect of the method 1 that is, only the quasi-static CFI value is only possible number of CC is greater. The CIF table is configured via RRC signaling. 3 is a table to show an example, when two CFI value, N1 and N2 is the signal via the RRC signaling. CFI value of dynamic signaling by this table can be used for the N1 and N2. RRc additional signaling may allow more yungnyeo rainbow trout a CIF maps.
Potential PHICH resource conflicts rainbow trout that cells with a small number of uplink MU-MIMO configurations and PHICH group already exists in the LTE Rel.8. This problem can be solved by the eNB scheduler is used in the UL DM RS cyclic shift shown acceptable response. Therefore, PHICH resource collision rainbow trout avoidance is a unique feature rainbow trout of LTE Rel.8 eNB scheduler that can be applied to both single and split PHICH resources.
R1-100041 Ericsson, ST-Ericsson Mapping of CIF to component carriers
'LTE> rainbow trout RAN' other articles of the category TDD eIMTA Part.1 (0) 2014/07/10 LTE-A 3DL, 1U
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