Variable single carrier frequency division multiple access (SC-FDMA) coding

• US 20110080877A1
• Filed: 10/05/2009
• Published: 04/07/2011
• Est. Priority Date: 10/05/2009
• Status: Abandoned Application

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Nentwig, Markus
• Application Number:
  US12/588,118
• Publication Number:
  US 20110080877A1
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/005 Iterative decoding, including iteration between signal detection and decoding operation
• CPC Class Codes: H04L 1/0066 Parallel concatenated codes
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1822 involving configuration of automatic repeat request [ARQ] with parallel processes
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04W 52/262 taking into account adaptive modulation and coding [AMC] scheme AMC per se H04L1/0001

Abstract

A method can include applying a first modulation and coding scheme to a first part of a symbol, applying a second modulation and coding scheme to a second part of the symbol, and combining the first part of the symbol and the second part of the symbol to form the symbol to be transmitted. The first modulation and coding scheme differs from the second modulation and coding scheme and wherein the first part of the symbol is temporally different from the second part of the symbol.

Claims

1. A method, comprising:

applying a first modulation and coding scheme to a first part of a symbol;

applying a second modulation and coding scheme to a second part of the symbol; and

combining the first part of the symbol and the second part of the symbol to form the symbol to be transmitted,

wherein the first modulation and coding scheme differs from the second modulation and coding scheme and wherein the first part of the symbol is temporally different from the second part of the symbol.

2. The method of claim 1, further comprising:

selecting at least one of the first modulation and coding scheme or the second modulation and coding scheme based on a respective transmission environment parameter depending on a transmission context of a corresponding part of the symbol.

3. The method of claim 1, further comprising:

selecting at least one of the first modulation and coding scheme or the second modulation and coding scheme based on an expected signal-to-noise ratio of a corresponding part of the symbol.

4. The method of claim 1, further comprising:

obtaining an estimate of a first transmission environment parameter for the first part of the symbol; and

obtaining an estimate of a second transmission environment parameter for the second part of the symbol,

wherein application of the first modulation and coding scheme is based on the first transmission environment parameter and application of the second modulation and coding scheme is based on the second transmission environment parameter.

5. The method of claim 1, further comprising:

applying a first transmit power to the first part of the symbol; and

applying a second transmit power to a second part of the symbol,

wherein the first transmit power is different from the second transmit power.

6. The method of claim 1, wherein the applying the first modulation and coding scheme to the first part of the symbol comprises applying the first modulation and coding scheme to the head and the tail of the symbol, and wherein the applying the second modulation and coding scheme to the second part of the symbol, comprises applying the second modulation and coding scheme to the middle of the symbol.

7. The method of claim 1, further comprising:

dividing a data stream into a plurality of data streams;

performing the applying the first modulating and coding scheme on a first data stream of the plurality of streams; and

performing the applying the second modulating and coding scheme on a second data stream of the plurality of streams.

8. An apparatus, comprising:

at least one memory including computer program code;

at least one processor,

wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to perform

apply a first modulation and coding scheme to a first part of a symbol;

apply a second modulation and coding scheme to a second part of the symbol; and

combine the first part of the symbol and the second part of the symbol to form the symbol to be transmitted,

wherein the first modulation and coding scheme differs from the second modulation and coding scheme and wherein the first part of the symbol is temporally different from the second part of the symbol.

9. The apparatus of claim 8, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to perform:

select at least one of the first modulation and coding scheme or the second modulation and coding scheme based on a respective transmission environment parameter depending on the transmission context of the corresponding part of the symbol.

10. The apparatus of claim 8, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to perform:

select at least one of the first modulation and coding scheme or the second modulation and coding scheme based on an expected signal-to-noise ratio of the corresponding part of the symbol.

11. The apparatus of claim 8, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to perform:

obtain an estimate of a first transmission environment parameter for the first part of the symbol; and

obtain an estimate of a second transmission environment parameter for the second part of the symbol,

wherein application of the first modulation and coding scheme is based on the first transmission environment parameter and application of the second modulation and coding scheme is based on the second transmission environment parameter.

12. The apparatus of claim 8, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to perform:

apply a first transmit power to the first part of the symbol; and

apply a second transmit power to a second part of the symbol,

wherein the first transmit power is different from the second transmit power.

13. The apparatus of claim 8, wherein the first part of the symbol comprises the head and the tail of the symbol, and wherein the second part of the symbol comprises the middle of the symbol.

14. The apparatus of claim 8, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to perform:

divide a data stream into a plurality of data streams;

perform the applying the first modulating and coding scheme on a first data stream of the plurality of streams; and

perform the applying the second modulating and coding scheme on a second data stream of the plurality of streams.

15. A method, comprising:

estimating a time-varying signal-to-noise ratio over at least one predetermined time interval of a transmission symbol, relative to a start of the transmission symbol, at a receiver to yield an estimate; and

initiating transmission of the estimate to a transmitter at an opposite end of a communication link from the receiver.

16. The method of claim 15, wherein the estimating is done based on an average of a large number of received symbols.

17. The method of claim 15, further comprising:

receiving a transmission symbol comprising a first part and a second part;

demodulating the first part of the transmission symbol according to a first modulation and coding scheme; and

demodulating the second part of the transmission symbol according to a second modulation and coding scheme,

wherein the first modulation and coding scheme differs from the second modulation and coding scheme.

18. An apparatus, comprising:

at least one memory including computer program code; and

at least one processor,

wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to perform

estimate a time-varying signal-to-noise ratio over at least one predetermined time interval of a transmission symbol, relative to a start of the transmission symbol, to yield an estimate; and

initiate transmission of the estimate to a transmitter at an opposite end of a communication link from the apparatus.

19. The apparatus of claim 18, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to estimate the signal-to-noise ratio based on an average of a large number of received symbols.

20. The apparatus of claim 18, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to perform:

receive a transmission symbol comprising a first part and a second part;

demodulate the first part of the transmission symbol according to a first modulation and coding scheme; and

demodulate the second part of the transmission symbol according to a second modulation and coding scheme,

wherein the first modulation and coding scheme differs from the second modulation and coding scheme.