Method and apparatus for implementing space frequency block coding in an orthogonal frequency division multiplexing wireless communication system
A method and apparatus for implementing space frequency block coding (SFBC) in an orthogonal frequency division multiplexing (OFDM) wireless communication system may be provided. Channel quality information (CQI) may be received, for example, on a per group of OFDM sub-carrier basis. A channel coded data stream may be generated. SFBC encoding may be performed on the channel coded data stream in an open loop mode, for example, such that the SFBC encoding is performed using a plurality of pairs of OFDM sub-carriers. A portion of the channel coded data stream that is SFBC encoded using a pair of OFDM sub-carriers of an OFDM symbol may be SFBC encoded independently of another portion of the channel coded data stream that is SFBC encoded using other pairs of OFDM sub-carriers of the OFDM symbol. The SFBC encoded data may be transmitted over the plurality of OFDM sub-carriers as an OFDM signal.
1. A transmitter comprising:
a plurality of transmit antennas;
circuitry configured to receive channel quality information (CQI), wherein the CQI is received on a per group of orthogonal frequency division multiplexing (OFDM) sub-carrier basis;
wherein the circuitry is further configured to generate a channel coded data stream;
wherein the circuitry is further configured to perform space frequency block coding (SFBC) encoding on the channel coded data stream in an open loop mode such that the SFBC encoding is performed using a plurality of pairs of OFDM sub-carriers, wherein a portion of the channel coded data stream that is SFBC encoded using a pair of OFDM sub-carriers of an OFDM symbol is SFBC encoded independently of another portion of the channel coded data stream that is SFBC encoded using other pairs of OFDM sub-carriers of the OFDM symbol; and
wherein the circuitry is further configured to transmit the SFBC encoded data stream over the plurality of pairs of OFDM sub-carriers using the plurality of transmit antennas as an OFDM signal.
2. The transmitter of claim 1 , wherein the circuitry is further configured to generate the channel coded data stream based on the received CQI, and wherein channel state information (CSI) is not provided to the transmitter by a receiver device that receives the OFDM symbol when operating in the open loop mode.
3. The transmitter of claim 1 , wherein each portion of the channel coded data stream that is SFBC encoded using a pair of OFDM sub-carriers is encoded using an Alamouti type SFBC code.
4. The transmitter of claim 1 , wherein the circuitry is further configured to select a coding rate and modulation type used for the channel coded data stream on a per group of OFDM sub-carrier basis based on the received CQI.
5. The transmitter of claim 1 , wherein the transmitter is a base station.
6. The transmitter of claim 2 , wherein the CSI is used for precoding at the transmitter.
7. A method comprising:
receiving channel quality information (CQI), wherein the CQI is received on a per group of orthogonal frequency division multiplexing (OFDM) sub-carrier basis;
generating a channel coded data stream;
performing space frequency block coding (SFBC) encoding on the channel coded data stream in an open loop mode such that the SFBC encoding is performed using a plurality of pairs of OFDM sub-carriers, wherein a portion of the channel coded data stream that is SFBC encoded using a pair of OFDM sub-carriers of an OFDM symbol is SFBC encoded independently of another portion of the channel coded data stream that is SFBC encoded using other pairs of OFDM sub-carriers of the OFDM symbol; and
transmitting the SFBC encoded data stream over the plurality of pairs of OFDM sub-carriers using a plurality of transmit antennas as an OFDM signal.
8. The method of claim 7 , further comprising:
generating the channel coded data stream based on the received CQI, wherein channel state information (CSI) is not provided by a receiver device that receives the OFDM symbol when operating in the open loop mode.
9. The method of claim 7 , wherein each portion of the channel coded data stream that is SFBC encoded using a pair of OFDM sub-carriers is encoded using an Alamouti type SFBC code.
10. The method of claim 7 , further comprising:
selecting a coding rate and modulation type used for the channel coded data stream on a per group of OFDM sub-carrier basis based on the received CQI.
11. The method of claim 7 , wherein the method is performed by a base station.
12. The method of claim 8 , wherein the CSI is used for precoding.
13. A WTRU comprising a processor and a receiver, the processor configured to:
send channel quality information (CQI), wherein the CQI is sent on a per group of orthogonal frequency division multiplexing (OFDM) sub-carrier basis; and
receive, via the receiver, an OFDM signal, wherein the OFDM signal comprises a channel coded data stream that was space frequency block coding (SFBC) encoded in an open loop mode such that the SFBC encoding was performed using a plurality of pairs of OFDM sub-carriers, and wherein a portion of the channel coded data stream that is SFBC encoded using a pair of OFDM sub-carriers of an OFDM symbol is SFBC encoded independently of another portion of the channel coded data stream that is SFBC encoded using other pairs of OFDM sub-carriers of the OFDM symbol.
14. The WTRU of claim 13 , wherein the channel coded data stream was generated based on the sent CQI, and wherein channel state information (CSI) is not sent when operating in the open loop mode.
15. The WTRU of claim 13 , wherein each portion of the channel coded data stream that is SFBC encoded using a pair of OFDM sub-carriers is encoded using an Alamouti type SFBC code.
16. The WTRU of claim 13 , wherein the channel coded data stream is encoded according to a coding rate and modulation type on a per group of OFDM sub-carrier basis based on the sent CQI.
17. The WTRU of claim 13 , wherein the CQI is sent to an access point and wherein the OFDM signal is received from the access point.
18. The WTRU of claim 14 , wherein the CSI is used for precoding.
19. A method comprising:
sending channel quality information (CQI), wherein the CQI is sent on a per group of orthogonal frequency division multiplexing (OFDM) sub-carrier basis; and
receiving an OFDM signal, wherein the OFDM signal comprises a channel coded data stream that was space frequency block coding (SFBC) encoded in an open loop mode such that the SFBC encoding was performed using a plurality of pairs of OFDM sub-carriers, and wherein a portion of the channel coded data stream that is SFBC encoded using a pair of OFDM sub-carriers of an OFDM symbol is SFBC encoded independently of another portion of the channel coded data stream that is SFBC encoded using other pairs of OFDM sub-carriers of the OFDM symbol.
20. The method of claim 19 , wherein the channel coded data stream was generated based on the sent CQI, and wherein channel state information (CSI) is not sent when operating in the open loop mode.
21. The method of claim 19 , wherein each portion of the channel coded data stream that is SFBC encoded using a pair of OFDM sub-carriers is encoded using an Alamouti type SFBC code.
22. The method of claim 19 , wherein the channel coded data stream is encoded according to a coding rate and modulation type on a per group of OFDM sub-carrier basis based on the sent CQI.
23. The method of claim 19 , wherein the CQI is sent to an access point and wherein the OFDM signal is received from the access point.
24. The method of claim 19 , wherein the method is performed by a WTRU.
25. The method of claim 20 , wherein the CSI is used for precoding.