Method and apparatus for configuring cell-specific reference signal

• US 9,270,436 B2
• Filed: 10/24/2011
• Issued: 02/23/2016
• Est. Priority Date: 06/21/2011
• Status: Active Grant

• Current Assignee: Xi'An Zhongxing New Software Co., Ltd. (ZTE Corporation)
• Original Assignee: ZTE Corporation
• Inventors: Liu, Xuebin, Li, Lian, Dong, Hui
• Primary Examiner(s): Marcelo, Melvin
• Assistant Examiner(s): Solinsky, Peter
• Application Number:
  US14/128,186
• Publication Number:
  US 20140133426A1
• Time in Patent Office: 1,583 Days
• Field of Search: 370/329
• US Class Current: 1/1
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/16 Deriving transmission power values from another channel
• CPC Class Codes: H04W 52/283 Power depending on the position of the mobile
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels

Abstract

The disclosure provides a method and an apparatus for configuring a Cell-Specific Reference Signal (CRS). The method includes: a cell is divided into a central area and a marginal area; a CRS is divided into a central CRS, a marginal CRS and a common CRS; a value that is obtained by adding a fixed first power value to a preset reference Energy Per Resource Element (EPRE) is configured as an EPRE value of the marginal CRS; a value that is obtained by subtracting a fixed second power value from the preset reference EPRE is configured as an EPRE value of the central CRS; and the reference EPRE is configured as the EPRE value of the common CRS. The disclosure can improve an SINR of a marginal area of a cell and enhance downlink performance of a UE in the marginal area of the cell, without affecting downlink performance of a UE in a central area of the cell.

Claims

1. A method for configuring a Cell-Specific Reference Signal (CRS) in a cell including a central area and a marginal area, wherein the central area is an area in which a difference value of Reference Signal Received Power (RSRP) between the cell and a neighbour cell is higher than a predefined threshold and the marginal area is an area in which the difference value of Reference Signal Received Power (RSRP) between the cell and the neighbour cell is lower than the predefined threshold, the method comprising:

dividing the CRS into a central CRS, a marginal CRS and a common CRS, wherein the central CRS is a CRS which is located on a transmission resource section used in the central area of the cell and is on a same symbol as a dedicated channel of the central area;

the marginal CRS is a CRS which is located on a transmission resource section used in the marginal area of the cell and is on a same symbol as a dedicated channel of the marginal area; and

the common CRS is a CRS, except for the central CRS and the marginal CRS, which is adjacent to a downlink common channel in frequency domain and is on a same symbol as the downlink common channel;

configuring a value that is obtained by adding a fixed first power value to a preset reference Energy Per Resource Element (EPRE), as an EPRE value of the marginal CRS;

configuring a value that is obtained by subtracting a fixed second power value from the preset reference EPRE, as an EPRE value of the central CRS;

configuring the reference EPRE as an EPRE value of the common CRS; and

receiving and transmitting data between the cell and a User Equipment (UE) with respect to the configured values.

2. The method according to claim 1, wherein the dedicated channel comprises:

a Physical Downlink Shared Channel (PDSCH) bearing User Equipment (UE) dedicated data and a Physical Downlink Control Channel (PDCCH) bearing UE dedicated scheduling information.

3. The method according to claim 2, wherein when the transmission resource is frequency domain resource, the first power value and the second power value are determined through:

determining a first difference between an EPRE of a preset dedicated PDSCH of the marginal area of the cell and the reference EPRE, and determining a second difference between an EPRE of a preset dedicated PDSCH of the central area of the cell and the reference EPRE; and

setting the first difference as the first power value, and setting the second difference as the second power value;

wherein the first difference, the first power value, the second difference and the second power value satisfy that;

a sum of, a configured power of the dedicated PDSCH of the central area of the cell and a configured power of the central CRS, a configured power of the dedicated PDSCH of the marginal area of the cell and a configured power of the marginal CRS, and a configured power of the common CRS and a configured power of the common channel of the cell is, on a same symbol, not greater than a maximum power of the cell.

4. The method according to claim 2, wherein when the transmission resource is frequency domain resource, the first power value and the second power value are determined through:

determining a first difference between an EPRE of a preset dedicated PDSCH of the marginal area of the cell and the reference EPRE, and determining a second difference between an EPRE of a preset dedicated PDSCH of the central area of the cell and the reference EPRE; and

according to a result of system simulation and network testing, adjusting the first difference to obtain the first power value, and adjusting the second difference to obtain the second power value;

wherein the first difference, the first power value, the second difference and the second power value satisfy that;

a sum of, a configured power of the dedicated PDSCH of the central area of the cell and a configured power of the central CRS, a configured power of the dedicated PDSCH of the marginal area of the cell and a configured power of the marginal CRS, and a configured power of the common CRS and a configured power of the common channel of the cell is, on a same symbol, not greater than a maximum power of the cell.

5. The method according to claim 2, wherein when the transmission resource is time domain resource, the first power value and the second power value are determined through:

determining a first difference between an EPRE of a preset dedicated PDSCH of the marginal area of the cell and the reference EPRE;

setting the first difference as a first power value of a marginal CRS which is on the same symbol as the dedicated PDSCH;

determining a second difference between an EPRE of a preset dedicated PDSCH of the central area of the cell and the reference EPRE;

setting the second difference as a second power value of a central CRS which is on the same symbol as the dedicated PDSCH;

determining a third difference between an EPRE of a preset dedicated PDCCH of the marginal area of the cell and the reference EPRE;

setting the third difference as a first power value of a marginal CRS which is on the same symbol as the dedicated PDCCH;

determining a fourth difference between an EPRE of a preset dedicated PDCCH of the central area of the cell and the reference EPRE; and

setting the fourth difference as a second power value of a central CRS which is on the same symbol as the dedicated PDCCH;

wherein the first difference, the first power value of the marginal CRS which is on the same symbol as the dedicated PDSCH, the second difference, the second power value of the central CRS which is on the same symbol as the dedicated PDSCH, the third difference, the first power value of the marginal CRS which is on the same symbol as the dedicated PDCCH, and the fourth difference and the second power value of the central CRS which is on the same symbol as the dedicated PDCCH satisfy that;

a sum of, a configured power of the dedicated PDCCH of the central area of the cell and a configured power of the dedicated PDSCH of the central area of the cell and a configured power of the central CRS, a configured power of the dedicated PDCCH of the marginal area of the cell and a configured power of the dedicated PDSCH of the marginal area of the cell and a configured power of the marginal CRS, and a configured power of the common CRS and a configured power of the common channel of the cell is, on a same symbol, not greater than a maximum power of the cell.

6. The method according to claim 2, wherein when the transmission resource is time domain resource, the first power value and the second power value are determined through:

determining a first difference between an EPRE of a preset dedicated PDSCH of the marginal area of the cell and the reference EPRE;

determining a second difference between an EPRE of a preset dedicated PDSCH of the central area of the cell and the reference EPRE;

determining a third difference between an EPRE of a preset dedicated PDCCH of the marginal area of the cell and the reference EPRE; and

determining a fourth difference between an EPRE of a preset dedicated PDCCH of the central area of the cell and the reference EPRE; and

according to a result of system simulation and network testing, adjusting the first difference, the second difference, the third difference and the fourth difference respectively to obtain the first power value of the marginal CRS which is on the same symbol as the dedicated PDSCH, the second power value of the central CRS which is on the same symbol as the dedicated PDSCH, the first power value of the marginal CRS which is on the same symbol as the dedicated PDCCH and the second power value of the central CRS which is on the same symbol as the dedicated PDCCH;

wherein the first difference, the first power value of the marginal CRS which is on the same symbol as the dedicated PDSCH, the second difference, the second power value of the central CRS which is on the same symbol as the dedicated PDSCH, the third difference, the first power value of the marginal CRS which is on the same symbol as the dedicated PDCCH, and the fourth difference and the second power value of the central CRS which is on the same symbol as the dedicated PDCCH satisfy that;

a sum of, a configured power of the dedicated PDCCH of the central area of the cell and a configured power of the dedicated PDSCH of the central area of the cell and a configured power of the central CRS, a configured power of the dedicated PDCCH of the marginal area of the cell and a configured power of the dedicated PDSCH of the marginal area of the cell and a configured power of the marginal CRS, and a configured power of the common CRS and a configured power of the common channel of the cell is, on a same symbol, not greater than a maximum power of the cell.

7. The method according to claim 4, further comprising:

informing, through a signalling reconfiguration message, a UE in the cell of a power difference between the configured EPRE of the dedicated PDSCH of the marginal area of the cell and the configured EPRE of the marginal CRS which is on the same symbol as the dedicated PDSCH and a power difference between the configured EPRE of the dedicated PDSCH of the central area of the cell and the configured EPRE of the central CRS which is on the same symbol as the dedicated PDSCH.

14. The method according to claim 6, further comprising:

informing, through a signalling reconfiguration message, a UE in the cell of a power difference between the configured EPRE of the dedicated PDSCH of the marginal area of the cell and the configured EPRE of the marginal CRS which is on the same symbol as the dedicated PDSCH and a power difference between the configured EPRE of the dedicated PDSCH of the central area of the cell and the configured EPRE of the central CRS which is on the same symbol as the dedicated PDSCH.

8. An apparatus for configuring a Cell-Specific Reference Signal (CRS) in a cell including

a central area and a marginal area, wherein the central area is an area in which a difference value of Reference Signal Received Power (RSRP) between the cell and a neighbour cell is higher than a predefined threshold and the marginal area is an area in which the difference value of Reference Signal Received Power (RSRP) between the cell and the neighbour cell is lower than the predefined threshold, the apparatus comprising;

a CRS division unit, configured to divide the CRS into a central CRS, a marginal CRS and a common CRS, wherein the central CRS is a CRS which is located on a transmission resource section used in the central area of the cell and is on a same symbol as a dedicated channel of the central area;

the marginal CRS is a CRS which is located on a transmission resource section used in the marginal area of the cell and is on a same symbol as a dedicated channel of the marginal area; and

the common CRS is a CRS, except for the central CRS and the marginal CRS, which is adjacent to a downlink common channel in frequency domain and is on the same symbol as the downlink common channel;

a configuration unit, configured to;

configure a value that is obtained by adding a fixed first power value to a preset reference Energy Per Resource Element (EPRE), as an EPRE value of the marginal CRS;

configure a value that is obtained by subtracting a fixed second power value from the preset reference EPRE, as an EPRE value of the central CRS; and

configure the reference EPRE as an EPRE value of the common CRS; and

the apparatus configured to receive and transmit data between the cell and a User Equipment (UE) with respect to the configured values.

9. The apparatus according to claim 8, wherein the configuration unit comprises:

a determination subunit, configured to determine a first difference between an EPRE of a preset dedicated Physical Downlink Shared Channel (PDSCH) of the marginal area of the cell and the reference EPRE, and determine a second difference between an EPRE of a preset dedicated PDSCH of the central area of the cell and the reference EPRE; and

a value setting subunit, configured to set the first difference as the first power value and set the second difference as the second power value;

wherein the first difference, the first power value, the second difference and the second power value satisfy that;

a sum of, a configured power of the dedicated PDSCH of the central area of the cell and a configured power of the central CRS, a configured power of the dedicated PDSCH of the marginal area of the cell and a configured power of the marginal CRS, and a configured power of the common CRS and a configured power of the common channel of the cell is, on a same symbol, not greater than a maximum power of the cell.

10. The apparatus according to claim 8, wherein the configuration unit comprises:

a determination subunit, configured to determine a first difference between an EPRE of a preset dedicated PDSCH of the marginal area of the cell and the reference EPRE, and determine a second difference between an EPRE of a preset dedicated PDSCH of the central area of the cell and the reference EPRE; and

a value setting subunit, configured to, according to a result of system simulation and network testing, adjust the first difference to obtain the first power value and adjust the second difference to obtain the second power value;

wherein the first difference, the first power value, the second difference and the second power value satisfy that;

a sum of, a configured power of the dedicated PDSCH of the central area of the cell and a configured power of the central CRS, a configured power of the dedicated PDSCH of the marginal area of the cell and a configured power of the marginal CRS, and a configured power of the common CRS and a configured power of the common channel of the cell is, on a same symbol, not greater than a maximum power of the cell.

11. The apparatus according to claim 8, wherein the configuration unit comprises:

a determination sub-unit, configured to;

determine a first difference between an EPRE of a preset dedicated PDSCH of the marginal area of the cell and the reference EPRE;

determine a second difference between an EPRE of a preset dedicated PDSCH of the central area of the cell and the reference EPRE;

determine a third difference between an EPRE of a preset dedicated Physical Downlink Control Channel (PDCCH) of the marginal area of the cell and the reference EPRE; and

determine a fourth difference between an EPRE of a preset dedicated PDCCH of the central area of the cell and the reference EPRE; and

a value setting subunit, configured to;

set the first difference as a first power value of a marginal CRS which is on the same symbol as the dedicated PDSCH;

set the second difference as a second power value of a central CRS which is on the same symbol as the dedicated PDSCH;

set the third difference as a first power value of a marginal CRS which is on the same symbol as the dedicated PDCCH; and

set the fourth difference as a second power value of a central CRS which is on the same symbol as the dedicated PDCCH;

wherein the first difference, the first power value of the marginal CRS which is on the same symbol as the dedicated PDSCH, the second difference, the second power value of the central CRS which is on the same symbol as the dedicated PDSCH, the third difference, the first power value of the marginal CRS which is on the same symbol as the dedicated PDCCH, and the fourth difference and the second power value of the central CRS which is on the same symbol as the dedicated PDCCH satisfy that;

a sum of, a configured power of the dedicated PDCCH of the central area of the cell and a configured power of the dedicated PDSCH of the central area of the cell and a configured power of the central CRS, a configured power of the dedicated PDCCH of the marginal area of the cell and a configured power of the dedicated PDSCH of the marginal area of the cell and a configured power of the marginal CRS, and a configured power of the common CRS and a configured power of the common channel of the cell is, on a same symbol, not greater than a maximum power of the cell.

12. The apparatus according to claim 8, wherein the configuration unit comprises:

a determination sub-unit, configured to;

determine a first difference between an EPRE of a preset dedicated PDSCH of the marginal area of the cell and the reference EPRE;

determine a second difference between an EPRE of a preset dedicated PDSCH of the central area of the cell and the reference EPRE;

determine a third difference between an EPRE of a preset dedicated PDCCH of the marginal area of the cell and the reference EPRE; and

determine a fourth difference between an EPRE of a preset dedicated PDCCH of the central area of the cell and the reference EPRE; and

a value setting subunit, configured to;

according to a result of system simulation and network testing, adjust the first difference, the second difference, the third difference and the fourth difference respectively to obtain the first power value of the marginal CRS which is on the same symbol as the dedicated PDSCH, the second power value of the central CRS which is on the same symbol as the dedicated PDSCH, the first power value of the marginal CRS which is on the same symbol as the dedicated PDCCH and the second power value of the central CRS which is on the same symbol as the dedicated PDCCH;

wherein the first difference, the first power value of the marginal CRS which is on the same symbol as the dedicated PDSCH, the second difference, the second power value of the central CRS which is on the same symbol as the dedicated PDSCH, the third difference, the first power value of the marginal CRS which is on the same symbol as the dedicated PDCCH, and the fourth difference and the second power value of the central CRS which is on the same symbol as the dedicated PDCCH satisfy that;

a sum of, a configured power of the dedicated PDCCH of the central area of the cell and a configured power of the dedicated PDSCH of the central area of the cell and a configured power of the central CRS, a configured power of the dedicated PDCCH of the marginal area of the cell and a configured power of the dedicated PDSCH of the marginal area of the cell and a configured power of the marginal CRS, and a configured power of the common CRS and a configured power of the common channel of the cell is, on a same symbol, not greater than a maximum power of the cell.

13. The apparatus according to claim 10, further comprising:

a signalling reconfiguration message transmitting unit, configured to inform, through a signalling reconfiguration message, a User Equipment (UE) in the cell of a power difference between the configured EPRE of the dedicated PDSCH of the marginal area of the cell and the configured EPRE of the marginal CRS which is on the same symbol as the dedicated PDSCH and a power difference between the configured EPRE of the dedicated PDSCH of the central area of the cell and the configured EPRE of the central CRS which is on the same symbol as the dedicated PDSCH.

15. The apparatus according to claim 12, further comprising:

a signalling reconfiguration message transmitting unit, configured to inform, through a signalling reconfiguration message, a User Equipment (UE) in the cell of a power difference between the configured EPRE of the dedicated PDSCH of the marginal area of the cell and the configured EPRE of the marginal CRS which is on the same symbol as the dedicated PDSCH and a power difference between the configured EPRE of the dedicated PDSCH of the central area of the cell and the configured EPRE of the central CRS which is on the same symbol as the dedicated PDSCH.