System and method for multi-user and multi-cell MIMO transmissions

Patent metadata

Field	Value
Publication number	US-9094167-B2
Application number	US-69238510-A
Country	US
Kind code	B2
Filing date	Jan 22, 2010
Priority date	Feb 2, 2009
Publication date	Jul 28, 2015
Grant date	Jul 28, 2015

Abstract

A base station can communicate with a plurality of subscriber stations in a Multi-User (MU) Multiple-Input Multiple-Output (MIMO) system. The base station includes a transmitter and plurality of antenna configured to transmit control information. The base station can transmit a resource block to a first subscriber station. The resource block includes at least two downlink reference signal (DRS) patterns. The base station can assign a first DRS pattern for use by the first subscriber station. The base station informs the subscriber station regarding the assignment by reserving a state in a downlink grant. In response, the subscriber station can utilize the first DRS pattern as a pilot resource element and, optionally, avoid other DRS patterns.

First claim

What is claimed is:

1. For use in a wireless communication network, a first base station configured to perform a coordinated multipoint transmission to a plurality of subscriber stations, the first base station comprising:
a plurality of antennas configured to transmit data and control information;
a transmitter coupled to the plurality of antennas, the transmitter configured to transmit a plurality of symbols in a sub-frame; and
a controller comprising processing circuitry configured to use a scrambling sequence for a physical downlink shared channel (PDSCH) that is the same as used by a second base station functioning as an anchor cell and performing coordinated multipoint transmission with the first base station, and to synchronize the transmission of the plurality of symbols by puncturing PDSCH symbols assigned to a first portion of a PDSCH of the first base station, the first portion corresponding to a second portion of a PDSCH of the second base station, the second portion overlapping with a control region of the first base station when the first base station has a control region size greater than a control region size in the second base station.

2. The first base station as set forth in claim 1 , wherein the controller is configured to synchronize the transmission of the plurality of symbols by starting the transmission of the plurality of symbols with an equal symbol number in a corresponding resource element as in the transmission from the second base station.

3. For use in a wireless communication network, a first base station configured to perform a coordinated multipoint transmission to a plurality of subscriber stations, the first base station comprising:
a plurality of antennas configured to transmit data and control information;
a transmitter coupled to the plurality of antennas, the transmitter configured to transmit a plurality of symbols in a sub-frame; and
a controller comprising processing circuitry configured to synchronize the transmission of the plurality of symbols by puncturing PDSCH symbols assigned to a first portion of a PDSCH of the first base station, the first portion corresponding to a second portion of a PDSCH of the second base station, a second portion overlapping with a control region of the first base station when the first base station has a control region size greater than a control region size in the second base station.

4. The first base station as set forth in claim 3 , wherein the controller is configured to receive an uplink control information message comprising a common rank indicator.

5. The first base station as set forth in claim 3 , wherein the controller is configured to receive an uplink control information message comprising a common channel quality indicator.

6. For use in a wireless communication network, a subscriber station configured to receive a coordinated multipoint transmission from a plurality of base stations, the subscriber station comprising:
a plurality of antennas configured to receive data and control information; and
a receiver coupled to the plurality of antennas, the receiver configured to receive transmissions from at least two base stations using a same scrambling sequence for a physical downlink shared channel (PDSCH),
wherein a first of the base stations configured to function as a non-anchor cell uses the scrambling sequence generated by a second of the base stations configured to function as an anchor cell, and the first base station is configured to synchronize the transmission of the plurality of symbols by puncturing PDSCH symbols assigned to a first portion of a PDSCH of the first base station, the first portion corresponding to a second portion of a PDSCH of the second base station, the second portion overlapping with a control region of the first base station when the first base station has a control region size greater than the second base station.

7. The subscriber station as set forth in claim 6 , wherein the physical downlink shared channel (PDSCH) transmission from the first base station is synchronized with the PDSCH from the second base station such that the transmission of a plurality of symbols from the first base station is based on a physical control format indicator of the second base station.

8. The subscriber station as set forth in claim 6 , wherein the receiver is configured to receive punctured resource elements in the PDSCH of the transmission from the first base station.

9. The subscriber station as set forth in claim 6 , wherein the transmission of a plurality of symbols from the first base station is synchronized by starting a transmission of a plurality of symbols with an equal number of symbols in a corresponding resource element in a transmission from the second base station.

10. For use in a wireless communication network, a subscriber station configured to receive a coordinated multipoint transmission from a plurality of base stations, the subscriber station comprising:
a plurality of antennas configured to receive data and control information; and
a receiver coupled to the plurality of antennas, the receiver configured to receive a transmission of a plurality of symbols from a first base station, wherein the transmission is synchronized by puncturing PDSCH symbols assigned to a first portion of a PDSCH of the first base station, the first portion corresponding to a second portion of a PDSCH of a second base station, the second portion overlapping with a control region of the first base station when the first base station has a control region size greater than a control region size in the second base station.

11. The subscriber station as set forth in claim 10 , wherein the subscriber station further comprises a controller configured to transmit an uplink control information message to the plurality of base stations, the uplink control information message comprising a common rank indicator.

12. The subscriber station as set forth in claim 10 , wherein the subscriber station further comprises a controller configured to transmit an uplink control information message to the plurality of base stations, the uplink control information message comprising a common channel quality indicator.

13. For use in a wireless communication network, a method for operating a first base station capable of performing a coordinated multipoint transmission with a plurality of subscriber stations, the method comprising:
transmitting a plurality of symbols in a sub-frame;
using, by a controller, a scrambling sequence for a physical downlink shared channel (PDSCH) that is the same as used by a second base station functioning as an anchor cell and performing coordinated multipoint transmission with the first base station; and
synchronizing, by the controller, the transmission of the plurality of symbols by puncturing PDSCH symbols assigned to a first portion of a PDSCH of the first base station, the first portion corresponding to a second portion of a PDSCH of the second base station, the second portion overlapping with a control region of the first base station when the first base station has a control region size greater than the second base station.

14. The method as set forth in claim 13 , wherein synchronizing the transmission of the plurality of symbols comprises synchronizing the transmission of the plurality of symbols based on a physical control format indicator of the second base station.

15. The method as set forth in claim 14 , wherein synchronizing the transmission of the plurality of symbols comprises starting the transmission of the plurality of symbols with an equal symbol number in a corresponding resource element as in

Assignees

• Zhang Jianzhong
• Lee Juho
• Li Ying-Yang
• Liu Lingjia
• Nam Young-Han
• Samsung Electronics Co Ltd

Inventors

• Zhang Jianzhong
• Lee Juho
• Li Ying-Yang
• Liu Lingjia
• Nam Young-Han

Classifications

• H04L5/0048

  Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091) · CPC title

• H04L5/0094

  Indication of how sub-channels of the path are allocated · CPC title

• H04L5/0007

  the frequencies being orthogonal, e.g. OFDM(A) or DMT · CPC title

• H04B7/0452

  Multi-user MIMO systems · CPC title

• H04L5/0053 Primary

  Allocation of signalling, i.e. of overhead other than pilot signals · CPC title