METHOD AND APPARATUS TO ADJUST RECEIVED SIGNAL

• US 20110235622A1
• Filed: 03/26/2010
• Published: 09/29/2011
• Est. Priority Date: 03/26/2010
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: KASHER, Assaf
• Granted Patent: US 8,711,760 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 2025/03426 transmission using multiple-input and multiple-output channels
• CPC Class Codes: H04L 25/03343 Arrangements at the transmitter end
• CPC Class Codes: H04L 25/03891 Spatial equalizers MIMO diversity systems H04B7/0413
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 52/226 using past references to control power, e.g. look-up-table
• CPC Class Codes: H04W 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo

Abstract

A wireless communication device, a wireless communication system and a method to adjust transmitted signals constellation in a maximum likelihood multiple-input-multiple-output receiver by transmitting an EVM deviation value. The EVM deviation value may be added to a pre-stored error value at the receiver.

Claims

1. A method comprising:

measuring a noise level value; and

transmitting the noise level value indicating a quality of the noise level in relation to a required noise level for a transmitted constellation of data streams.

2. The method of claim 1, wherein transmitting the noise level value comprises:

transmitting a deviation of an error vector magnitude value (EVM) in a field of a frame.

3. The method of claim 2, comprising:

estimating an estimated EVM from a received signal;

calculating an EVM deviation value from a pre-stored EVM value and the estimated EVM; and

transmitting the deviation value with the field of the frame.

4. A method of adjusting a received signal in a multiple-input-multiple-output receivers system, the method comprising:

receiving a deviation of an error vector magnitude (EVM) value with a received data stream;

detecting a symbol from the received data stream using a maximum likelihood detection scheme;

adding the deviation EVM value to a pre-stored EVM value; and

placing the symbol on a desired constellation point.

5. The method of claim 4, wherein receiving comprises:

receiving a frame that include the deviation EVM value.

6. The method of claim 4, comprising:

receiving a modulation coding scheme and adding the EVM deviation value to a pre-stored EVM value according to the modulation coding scheme.

7. The method of claim 4 comprising:

adjusting the received signal for transmitter noise by adding the deviation EVM value to a pre-stored EVM value in order to place the symbol on a desired constellation point.

8. A wireless communication device comprising:

a multiple-input-multiple-output (MIMO) receivers system to receive a deviation of an error vector magnitude (EVM) value with a received data stream; and

a detector to detect a symbol from the received data stream using a maximum likelihood detection scheme and to add the deviation EVM value to a pre-stored EVM value and placing the symbol on a desired constellation point.

9. The wireless communication device of claim 8, wherein the MIMO receivers system is able to receive a frame that includes the deviation EVM value.

10. The wireless communication device of claim 9 wherein the frame includes a modulation coding scheme and the detector is able to add the EVM deviation value to a pre-stored EVM value according to the modulation coding scheme.

11. The wireless communication device of claim 8 comprising:

a memory to store in a table the pre stored EVM value, wherein;

the detector is able to adjust the received signal for a transmitter noise by adding the deviation EVM value to the pre-stored EVM value from the table in order to place the symbol on a desired constellation point.

12. The wireless communication device of claim 8 wherein the detector comprises a maximum likelihood detector.

13. The wireless communication device of claim 11 wherein the transmitter noise comprises white noise.

14. A wireless communication system comprising:

an antenna array operably coupled to a multiple-input-multiple-output (MIMO) receivers system to receive a deviation of an error vector magnitude (EVM) value with a received data stream; and

a detector to detect a symbol from the received data stream using a maximum likelihood detection scheme and to add the deviation EVM value to a pre-stored EVM value in order to place the symbol on a desired constellation point.

15. The wireless communication system of claim 14, wherein the MIMO receivers are able to receive a frame that includes the deviation EVM value.

16. The wireless communication system of claim 15 wherein the frame includes a modulation coding scheme and the detector is able to add the EVM deviation value to a pre-stored EVM value according to the modulation coding scheme.

17. The wireless communication system of claim 14 comprising:

a memory to store in a table the pre stored EVM value;

wherein

the detector is able to adjust the received signal for transmitter noise by adding the deviation EVM value to the pre-stored EVM value from the table in order to place the symbol on a desired constellation point.

18. The wireless communication system of claim 14 wherein the detector comprises a maximum likelihood detector.

19. The wireless communication system of claim 14 wherein the transmitter noise comprises white noise.

20. The wireless communication system of claim 14 is able to operate within a wireless local area network using Orthogonal Frequency-Division Multiplexing (OFDM) scheme.