Methods and arrangements for signaling control information in a communication system

Patent metadata

Field	Value
Publication number	US-9838099-B2
Application number	US-201615084905-A
Country	US
Kind code	B2
Filing date	Mar 30, 2016
Priority date	Oct 8, 2007
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

The invention relates to devices and methods for signalling control information associated with transmission of data over a wireless channel. A second communication device receives (S 2 ) data from a first communication device, wherein the data comprises an indication of recommended precoders and a recommendation of a first transmission rank to possibly use during transmission. The second communication device determines (S 4 ) a second transmission rank to use for transmitting data, and transmits (S 6 ) a confirmation message to the first communication device. The confirmation message comprises a confirmation that transmission of data from the second communication device is using at least parts of each recommended precoder associated with a frequency resource that falls within the transmission of data and an indicator of the second transmission rank to use.

First claim

The invention claimed is:

1. User equipment for communication with a base station over a radio channel, the user equipment comprising:
a processor for determining (R 2 ) a recommended precoder and a recommended transmission rank to possibly use when transmitting data from a base station;
a transmitter for transmitting (R 4 ) feedback data to the base station, wherein the feedback data comprise an indication of one recommended precoder per subband and the recommended transmission rank; and
a receiver for receiving (R 6 ) from the base station a message, wherein the message includes
a confirmation that transmission of data from the base station is using a column subset of each recommended precoder, and
an indicator of the transmission rank to be used, wherein said indicator also indicates which column or columns of the recommended precoder to use to support the transmission rank to be used, wherein the same column number or column numbers are selected for each precoder, and wherein the indicated transmission rank and the indicated column or columns of the recommended precoders are used to receive transmissions from the base station.

2. The user equipment according to claim 1 , wherein the processor for determining a recommended precoder is adapted to determine several precoders, one per subband,
wherein the feedback data to the base station comprise the indication of one recommended precoder per subband and the recommended transmission rank.

3. The user equipment according to claim 1 , wherein the feedback data to the base station comprise a single recommended transmission rank.

4. The user equipment according to claim 1 , wherein the transmitter is adapted to furthermore feed back quality assessments of the layers or codewords.

5. The user equipment according to claim 1 , wherein the message is coded with a message number.

6. The user equipment according claim 1 , wherein the same column number or column numbers are used for all precoders over frequency.

7. The user equipment according to claim 1 , wherein the message furthermore comprises codeword-to-layer mapping, and the user equipment is adapted to apply the codeword-to-layer mapping indicated in the message.

8. The user equipment according to claim 1 , wherein the recommended transmission rank is distinct from the transmission rank to be used.

9. A base station for communicating with a user equipment over a radio channel, the base station comprising:
a receiver for receiving (R 4 ) feedback data from the user equipment, wherein the feedback data comprise an indication of one recommended precoder per subband and a recommended transmission rank; and
a transmitter for transmitting to the user equipment a message, wherein the message includes
a confirmation that transmission of data from the base station is using a column subset of each recommended precoder, and
an indicator of the transmission rank to be used,

wherein said indicator also indicates which column or columns of the recommended precoder to use to support the transmission rank to be used,
wherein the same column number or column numbers are selected for each precoder, and wherein the indicated transmission rank and the indicated column or columns of the recommended precoder are used for transmissions to the user equipment.

10. The base station according to claim 9 , wherein the feedback data furthermore comprises quality assessments of the layers or codewords.

11. The base station according to claim 9 , wherein the base station is adapted to code the message that comprises a confirmation that transmission of data from the base station is using the recommended precoder and an indicator of the transmission rank to be used, by using a message number.

12. The base station according to claim 9 , wherein the same column number or column numbers are used for all precoders over frequency.

13. The base station according to claim 9 , wherein the message furthermore comprises codeword-to-layer mapping, and the base station is adapted to apply the codeword-to-layer mapping indicated in the message.

14. The base station according to claim 9 , wherein feedback data comprise several precoders, including one precoder per subband.

15. The base station according to claim 9 , wherein the feedback data comprise a single recommended transmission rank.

16. The base station according to claim 9 , wherein the recommended transmission rank is distinct from the transmission rank to be used.

Assignees

• Ericsson Telefon Ab L M
• Telefonaktiebolget Lm Ericsson (Publ)

Inventors

• Göransson Bo
• Jöngren George

Classifications

• H04W72/542

  using measured or perceived quality · CPC title

• H04W72/21

  in the uplink direction of a wireless link, i.e. towards the network · CPC title

• H04B7/0654

  at the receiver, e.g. antenna verification at mobile station · CPC title

• H04B7/0639

  Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection · CPC title

• H04B7/0417 Primary

  Feedback systems · CPC title