EXTENDING PHYSICAL DOWNLINK CONTROL CHANNELS

• US 20110075624A1
• Filed: 09/28/2010
• Published: 03/31/2011
• Est. Priority Date: 09/28/2009
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Papasakellariou, Aris, Cho, Joon-Young
• Granted Patent: US 9,295,043 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0092 Indication of how the channel is divided
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 48/10 using broadcasted information
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 72/1273 of downlink data flows
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 76/20 Manipulation of established connections
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support

Abstract

Methods and apparatus for transmitting and receiving Downlink Control Information (DCI) in a single cell in order to support communication over multiple cells. The DCI is conveyed by DCI formats transmitted through Physical Downlink Control CHannels (PDCCHs) in a UE-Common Search Space (UE-CSS) and in a UE-Dedicated Search Space (UE-DSS). A distinct UE-DSS is defined in the single cell for each of the multiple cells. Each distinct UE-DSS has the same structure as a conventional UE-DSS and a location that is determined by the same parameters as the location of the conventional UE-DSS and by the respective cell identity (Cell_ID).

Claims

1. A method for extending a Physical Downlink Control CHannel (PDCCH) region in a single cell to provide Downlink Control Information (DCI) to a User Equipment (UE) in order to enable communication over a plurality of cells in a communication system wherein the UE receives DCI from a Node B through a DCI format transmitted over a PDCCH and wherein the PDCCH is transmitted through Control Channel Elements (CCEs) in a UE-Common Search Space (UE-CSS) or in a UE-Dedicated Search Space (UE-DSS), the method comprising the steps of:

transmitting, by the Node B, PDCCHs in a UE-CSS; and

transmitting, by the Node B, PDCCHs in a plurality of UE-DSSs,

wherein the UE-CSS is common to the plurality of cells, and

wherein the plurality of UE-DSSs correspond to the plurality of cells, respectively.

2. The method of claim 1, wherein each of the plurality of UE-DSS has a same structure as the UE-DSS for communication over the single cell.

3. The method of claim 1, wherein the DCI formats include Cyclic Redundancy Check (CRC) bits and an intended cell for a DCI format transmitted in the UE-CSS is identified by applying a cell-specific mask to the CRC of the DCI format.

4. The method of claim 1, wherein each of the plurality of cells includes a cell identity which is UE-specific and informed to the UE through higher layer signaling from the Node B.

5. A method for extending a Physical Downlink Control CHannel (PDCCH) region in a single cell to provide Downlink Control Information (DCI) to a User Equipment (UE) in order to enable communication over a plurality of cells in a communication system wherein the UE receives DCI from a Node B through a DCI format transmitted over a PDCCH and wherein the PDCCH is transmitted through Control Channel Elements (CCEs) in a UE-Common Search Space (UE-CSS) or in a UE-Dedicated Search Space (UE-DSS), the method comprising the steps of:

informing the UE, by the Node B, of a Cell Identity (Cell_ID) for each of the plurality of cells;

defining a plurality of UE-DSSs corresponding to the plurality of cells, respectively, wherein each of the plurality of UE-DSSs is identified by parameters of the UE-DSS for the single cell and by the Cell_ID of a corresponding cell; and

transmitting a plurality of PDCCHs in the plurality of UE-DSSs.

6. The method of claim 5, wherein a DCI for the cell wherein a PDCCH is transmitted is provided only by the PDCCH in that cell.

7. The method of claim 5, wherein the UE-DSS for the cell wherein a PDCCH is transmitted is the same for single cell communication and for multiple cell communication.

8. The method of claim 5, wherein a predetermined subset of the DCI formats includes a Cell Indicator (CI) Information Element (IE) and remaining DCI formats in a set of DCI formats do not include the CI IE.

9. The method of claim 8, wherein the CI IE value is determined from a respective Cell_ID value.

10. The method of claim 9, wherein the CI value is the respective Cell_ID value.

11. The method of claim 8, wherein a number of bits for the CI IE in DCI formats providing DCI for a downlink of the communication system is different than a number of bits for the CI IE in DCI formats providing DCI for an uplink of the communication system.

12. The method of claim 8, wherein the CI IE is included in the DCI formats when cells have a same operating bandwidth, and is not included in the DCI formats when the cells have different operating bandwidths.

13. A User Equipment (UE) apparatus for receiving Downlink Control Information (DCI) in DCI formats transmitted from a Node B over Physical Downlink Control CHannels (PDCCHs) in a single cell, the DCI enabling communication over a plurality of cells, wherein a PDCCH is transmitted through Control Channel Elements (CCEs) in a UE-Common Search Space (UE-CSS) or in a UE-Dedicated Search Space (UE-DSS), the UE apparatus comprising:

a CCE identification unit for identifying CCEs in the UE-CSS and the UE-DSS; and

a receiver for receiving PDCCHs in the UE-CSS of the single cell and in a plurality of UE-DSSs, wherein the plurality of UE-DSSs corresponds to the plurality of cells, respectively.

14. The UE apparatus of claim 13, wherein each of the plurality of UE-DSSs has a same structure as the UE-DSS for communication over the single cell.

15. The UE apparatus of claim 13, wherein the DCI formats include Cyclic Redundancy Check (CRC) bits and an intended cell for a DCI format transmitted in the UE-CSS is identified by applying a cell-specific mask to the CRC of the DCI format.

16. The UE apparatus of claim 13, wherein each of the plurality of cells has a cell identity that is UE-specific and is informed to the UE through higher layer signaling from the Node B.

17. A User Equipment (UE) apparatus for receiving Downlink Control Information (DCI) in DCI formats transmitted from a Node B over Physical Downlink Control CHannels (PDCCHs) in a single cell, the DCI enabling communication over a plurality of cells, wherein a PDCCH is transmitted through Control Channel Elements (CCEs) in a UE-Common Search Space (UE-CSS) or in a UE-Dedicated Search Space (UE-DSS), the UE apparatus comprising of:

a receiver for receiving a Cell Identity (Cell_ID) for each of the plurality of cells transmitted by the Node B; and

a CCE identification unit for identifying CCEs in the UE-CSS and the UE-DSS; and

a receiver for receiving PDCCHs in the UE-CSS of the single cell and in a plurality of UE-DSSs corresponding to the plurality of cells, respectively,

wherein each of the plurality of UE-DSSs is identified by parameters of a UE-DSS for a single cell and by a Cell_ID of a corresponding cell.

18. The UE apparatus of claim 17, wherein a DCI for the cell wherein PDCCH is transmitted is provided only by a PDCCH in that cell.

19. The UE apparatus of claim 17, wherein at least one of the DCI formats includes a Cell Indicator (CI) Information Element (IE) and remaining DCI formats do not include the CI IE.

20. The UE apparatus of claim 19, wherein the CI IE value is determined from a respective Cell_ID value.

21. The UE apparatus of claim 20, wherein the CI value is the respective Cell_ID value.