Data symbol mapping for multiple-input multiple-output hybrid automatic repeat request

1. A system comprising:

an encoding module

that receives symbols for transmission over K subcarriers and T antennas,

that encodes the symbols using a space time code, and

that generates space time coded (STC) versions of the symbols, where K and T are integers greater than 1;

a symbol selection module that selects T adjacent ones of the symbols and that selects STC versions of the T adjacent ones of the symbols;

a subcarrier selection module that selects one of the K subcarriers for transmitting

the T adjacent ones of the symbols and

the STC versions of the T adjacent ones of the symbols; and

a mapping module

that maps the T adjacent ones of the symbols onto the T antennas for transmission over the selected one of the K subcarriers, respectively, and

that maps the STC versions of the T adjacent ones of the symbols onto the T antennas for transmission over the selected one of the K subcarriers.

2. The system of claim 1 , wherein the mapping module maps the T adjacent ones of the symbols onto the T antennas when the selected one of the K subcarriers is used at a first time, and wherein the mapping module maps the STC versions of the T adjacent ones of the symbols onto the T antennas when the selected one of the K subcarriers is used at a second time.

3. The system of claim 1 , wherein the mapping module maps the T adjacent ones of the symbols onto the T antennas in a first order of the T antennas, and maps the STC versions of the T adjacent ones of the symbols onto the T antennas in a second order of the T antennas that is opposite of the first order.

4. The system of claim 1 , wherein when one of the T adjacent ones of the symbols is mapped onto a first one of the T antennas, an STC version of the one of the T adjacent ones of the symbols is mapped onto a second one of the T antennas.

5. The system of claim 1 , wherein the STC versions of the T adjacent ones of the symbols include complex conjugates of the T adjacent ones of the symbols.

6. The system of claim 1 , wherein the symbols include orthogonal frequency division multiplexing (OFDM) symbols, and wherein the T antennas operate as multiple-input multiple-output (MIMO) antennas.

7. A transmitter comprising the system of claim 1 and further comprising:

the T antennas; and

T driver modules that drive the T antennas, respectively,

wherein the T driver modules transmit the T adjacent ones of the symbols over the selected one of the K subcarriers via the T antennas, respectively, and

wherein the T driver modules transmit the STC versions of the T adjacent ones of the symbols over the selected one of the K subcarriers via the T antennas.

8. A system comprising the transmitter of claim 7 and further comprising:

a receiver that includes:

a preprocessing module

that receives the T adjacent ones of the symbols and the STC versions of the T adjacent ones of the symbols transmitted over the one of the K subcarriers,

that decodes the STC versions of the T adjacent ones of the symbols, and

that generates decoded symbols;

a combining module that combines the decoded symbols and corresponding ones of the T adjacent ones of the symbols; and

a decoding module that decodes the T adjacent ones of the symbols based on a combination of

the decoded symbols and

the corresponding ones of the T adjacent ones of the symbols.

9. A receiver comprising:

a preprocessing module

that receives T adjacent symbols transmitted over a subcarrier via T antennas, respectively, where T is an integer greater than 1,

that receives space time coded (STC) versions of the T adjacent symbols transmitted over the subcarrier via the T antennas,

that decodes the STC versions of the T adjacent symbols, and

that generates decoded symbols;

a combining module that combines the decoded symbols and corresponding ones of the T adjacent symbols; and

a decoding module that decodes the T adjacent symbols based on a combination of

the decoded symbols and

the corresponding ones of the T adjacent symbols.

10. A transmitter comprising:

a control module that selects first and second mapping modes to map symbols onto K subcarriers and T antennas during first and second transmissions of the symbols, respectively, where K and T are integers greater than 1;

a first mapping module that maps T adjacent ones of the symbols onto the T antennas for transmission over one of the K subcarriers, respectively, when the first mapping mode is selected; and

a second mapping module

that maps the T adjacent ones of the symbols onto the T antennas for transmission over the one of the K subcarriers, respectively, and

that maps space time coded (STC) versions of the T adjacent ones of the symbols onto the T antennas for transmission over the one of the K subcarriers when the second mapping mode is selected.

11. The transmitter of claim 10 , wherein the second mapping module maps the T adjacent ones of the symbols onto the T antennas, respectively, when the one of the K subcarriers is used at a first time, and wherein the second mapping module maps the STC versions of the T adjacent ones of the symbols onto the T antennas when the one of the K subcarriers is used at a second time that occurs after the first time.

12. The transmitter of claim 10 wherein:

the T adjacent ones of the symbols are mapped onto the T antennas in a first order of the T antennas in the first and second mapping modes; and

the STC versions of the T adjacent ones of the symbols are mapped onto the T antennas in a second order of the T antennas in the second mapping mode, where the second order is opposite of the first order.

13. The transmitter of claim 10 wherein when one of the T adjacent ones of the symbols is mapped onto a first one of the T antennas in the second mapping mode, an STC version of the one of the T adjacent ones of the symbols is mapped onto a second one of the T antennas.

14. The transmitter of claim 10 wherein the STC versions of the T adjacent ones of the symbols include complex conjugates of the T adjacent ones of the symbols.

15. The transmitter of claim 10 wherein the symbols include orthogonal frequency division multiplexing (OFDM) symbols, and wherein the T antennas operate as multiple-input multiple output (MIMO) antennas.

16. The transmitter of claim 10 further comprising:

the T antennas; and

T driver modules that drive the T antennas, respectively,

wherein the T driver modules transmit the T adjacent ones of the symbols over the one of the K subcarriers via the T antennas, respectively, during the first and second transmissions, and

wherein the T driver modules transmit the STC versions of the T adjacent ones of the symbols over the one of the K subcarriers via the T antennas during the second transmission.

17. A system comprising the transmitter of claim 16 and further comprising:

a receiver that includes:

a preprocessing module that receives the T adjacent ones of the symbols transmitted over the one of the K subcarriers via the T antennas, respectively, during the first and second transmissions;

a combining module that combines

the T adjacent ones of the symbols transmitted over the one of the K subcarriers via the T antennas during the first transmission with

corresponding ones of the T adjacent ones of the symbols transmitted over the one of the K subcarriers via the T antennas during the second transmission; and

a decoding module that decodes the T adjacent ones of the symbols based on a combination of the T adjacent ones of the symbols transmitted over the one of the K subcarriers via the T antennas during the first and second transmissions.

18. A system comprising the transmitter of claim 16 and further comprising:

a receiver that includes:

a preprocessing module

that receives the T adjacent ones of the symbols and the STC versions of the T adjacent ones of the symbols transmitted over the one of the K subcarriers during the second transmission,

that decodes the STC versions of the T adjacent ones of the symbols, and

that generates decoded symbols;

a combining module that combines the decoded symbols and corresponding ones of the T adjacent ones of the symbols; and

a decoding module that decodes the T adjacent ones of the symbols based on a combination of

the decoded symbols and

the corresponding ones of the T adjacent ones of the symbols.

19. A receiver comprising:

a preprocessing module

that receives T adjacent symbols transmitted over a subcarrier via T antennas during a first transmission, respectively, where T is an integer greater than 1, and

that receives the T adjacent symbols and space time coded (STC) versions of the T adjacent symbols transmitted over the subcarrier via the T antennas during a second transmission;

a combining module that combines

the T adjacent symbols transmitted over the subcarrier via the T antennas during the first transmission with

corresponding ones of the T adjacent symbols transmitted over the subcarrier via the T antennas during the second transmission; and

a decoding module that decodes the T adjacent symbols based on a combination of the T adjacent symbols transmitted over the subcarrier via the T antennas during the first and second transmissions.