MIMO control signaling in a wireless communication system

A method for performing data transmission, the method comprising the steps of:

• modulating a data signal at a transmitter with either a single codeword or two codewords;
• transmitting the modulated data signal accompanied by a control signal via the transmitter, with:
• when the data signal is modulated with the single codeword, the control signal is coded with a first signal format for carrying information regarding the single codeword;
• when the data signal is modulated with the two codewords transmission is used, the control signal is coded with a second signal format for carrying information regarding both of the two codewords.

A transmitter for transmitting data to a receiver,

• the transmitter modulating a data signal with either a single codeword or two codewords, with:
• when the transmitter modulates the data signal with the single codeword, the transmitter coding a control signal using a first signal format for carrying information regarding the single codeword, and
• when the transmitter modulates the data signal with the two codewords, the transmitter coding the control signal using a second signal format for carrying information regarding both of the two codewords, and
• the transmitter transmitting the control signal accompanied by the control signal.

A receiver for receiving data signal accompanied by a control signal from a transmitter, comprising:

• a decoder decoding the control signal using either a first signal format or a second signal format, the first signal format being used when the data signal has been transmitted using a single codeword, and the second signal format being used when the data signal has been transmitted using a second codeword;
• a first determination unit determining whether the control signal has been decoded by the decoder;
• a processor processing the data signal;
• and
• a control unit sending instructions to:
• instruct the decoder to decode the control signal using the first signal format;
• instruct the first determination unit to determine whether the control signal has been decoded by using the first signal format;
• when the control signal is decoded using the first signal, instruct the processor to process the data signal by assuming that the data is transmitted using the single codeword transmission;
• when the the control signal is not decoded, instruct the decoder to decode the control signal using the second signal format;
• instruct the first determination unit to determine whether the decoding using the second signal format is successfully performed;
• when the control signal is decoded using the second signal format, instruct the processor to process the data signal by assuming that the data is transmitted using the two codewords transmission;
• and
• when the control signal is not decoded using the second signal format, terminating the processing of the data signal.