APPARATUS AND METHOD FOR TRANSMITTING OF CHANNEL QUALITY INDICATOR AND ACKNOWLEDGEMENT SIGNALS IN SC-FDMA COMMUNICATION SYSTEMS

• US 20090022135A1
• Filed: 07/16/2008
• Published: 01/22/2009
• Est. Priority Date: 07/16/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: PAPASAKELLARIOU, Aris, Cho, Joon-Young
• Granted Patent: US 8,391,268 B2
• Time in Patent Office: Days
• US Class Current: 370/344
• CPC Class Codes: H04J 11/00 Orthogonal multiplex systems, e.g. using WALSH codesH04J13/00 takes precedence
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 23/02 adapted for orthogonal signalling
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals

Abstract

A method and apparatus for multiplexing positive or negative acknowledgement signals (ACK or NACK, respectively) and channel quality indication (CQI) signals from a user equipment (UE) to a serving base station (Node B) during a CQI transmission time interval (TTI) in a single-carrier frequency division multiple access (SC-FDMA) communication system. The UE does not have simultaneous data transmission. The multiplexing of acknowledgement signals is implicitly achieved by the UE applying different orthogonal covers on the reference signal (RS) symbols transmitted in the CQI TTI, depending on whether the UE sends ACK or NACK. At the Node B receiver, the detection of ACK or NACK is based on the accumulated RS energy, after removing each of the possible orthogonal covers applied at the UE transmitter. For robust system performance, absence of ACK/NACK and NACK are mapped onto the same orthogonal cover.

Claims

1. A method for transmitting a first type of information bits using a signal in a communication system, the signal having a duration of at least one slot, the at least one slot including a first number and a second number of symbols, wherein a reference signal is transmitted in the first number of symbols and a second type of information bits are transmitted in the second number of symbols, the method comprising:

scaling the first number of symbols by a first orthogonal cover, if an information bit of the first type has a first value;

scaling the first number of symbols by a second orthogonal cover, if the information bit of the first type has a second value; and

transmitting the first number of symbols.

2. The method as in claim 1, wherein the first type of information bits are acknowledgement (ACK/NACK) bits associated with correct (ACK) or incorrect (NACK) reception of data.

3. The method as in claim 1, wherein the second type of information bits are Channel Quality Indication (CQI) bits.

4. The method as in claim 1, wherein the first number of symbols is two, the first orthogonal cover is {1, 1}, and the second orthogonal cover is {1, −

1}.

5. A method for receiving a first type of information bits using a signal in a communication system, the signal having a duration of at least one slot, the at least one slot including a first number and a second number of symbols, wherein a reference signal is received in the first number of symbols and a second type of information bits are received in the second number of symbols, the method comprising:

scaling the first number of symbols by a first orthogonal cover to acquire a scaled first number of symbols;

summing the scaled first number of symbols to obtain a first energy value;

scaling the first number of symbols by a second orthogonal cover to acquire a scaled second number of symbols;

summing the scaled second number of symbols to obtain a second energy value;

comparing the first energy value and the second energy value;

determining a first value for the first type of information bits, if the first energy value is larger than the second energy value; and

determining a second value for the first type of information bits, if the second energy value is larger than the first energy value.

6. The method as in claim 5, wherein the first type of information bits are acknowledgement (ACK/NACK) bits associated with correct (ACK) or incorrect (NACK) reception of data.

7. The method as in claim 5, wherein the second type of information bits are Channel Quality Indication (CQI) bits.

8. The method as in claim 5, further comprising:

determining a channel estimate by applying the first orthogonal cover to the first number of symbols, if the first energy value is larger than the second energy value, and by applying the second orthogonal cover to the first number of symbols, if the second energy value is larger than the first energy value.

9. The method as in claim 5, wherein the first number of symbols is two, the first orthogonal cover is {1, 1}, and the second orthogonal cover is {1, −

1}.

10. A method for transmitting positive and negative acknowledgement (ACK/NACK) bits using a signal in a communication system, the acknowledgement (ACK/NACK) bits are in response to data reception, the signal having a duration of at least one slot, the at least one slot including a first number and a second number of symbols, wherein a reference signal is transmitted in the first number of symbols, the method comprising:

scaling the first number of symbols by a first orthogonal cover, if the acknowledgement bit is negative (NACK);

scaling the first number of symbols by a second orthogonal cover, if the acknowledgement bit is positive (ACK);

scaling the first number of symbols by the first orthogonal cover, if no acknowledgement bit exists; and

transmitting the first number of symbols.

11. The method as in claim 10, wherein the first number of symbols is two, the first orthogonal cover is {1, 1}, and the second orthogonal cover is {1, −

1}.

12. The method as in claim 10, wherein the communication system is a single-carrier frequency domain multiple access communication system.

13. An apparatus for transmitting a first type of information bits using a signal in a communication system, the signal having a duration of at least one slot, the at least one slot including a first number and a second number of symbols, wherein a reference signal is transmitted in the first number of symbols and a second type of information bits are transmitted in the second number of symbols, the apparatus comprising:

a multiplier unit for scaling the first number of symbols by a first orthogonal cover, if an information bit of the first type has a first value, and for scaling the first number of symbols by a second orthogonal cover, if the information bit of the first type has a second value; and

a transmitter unit for transmitting the first number of symbols.

14. The apparatus as in claim 13, wherein the first type of information bits comprise acknowledgement bits (ACK/NACK) associated with the correct (ACK) or incorrect (NACK) reception of data.

15. The apparatus as in claim 13, wherein the second type of information bits comprise Channel Quality Indication (CQI) bits.

16. The apparatus as in claim 13, wherein the first number of symbols is two, the first orthogonal cover is {1, 1}, and the second orthogonal cover is {1, −

1}.

17. The apparatus as in claim 13, wherein the communication system comprises a single-carrier frequency domain multiple access communication system.

18. An apparatus for transmitting positive or negative acknowledgement (ACK/NACK) bits using a signal in a communication system, the acknowledgement (ACK/NACK) bits are in response to data reception, the signal having a duration of at least one slot, the at least one slot including a first number and a second number of symbols, wherein a reference signal is transmitted in the first number of symbols, the apparatus comprising:

a multiplier unit for scaling the first number of symbols by a first orthogonal cover, if the acknowledgement bit is negative (NACK), or if no acknowledgement bit exists, and for scaling the first number of symbols by a second orthogonal cover, if the acknowledgement bit is positive (ACK); and

a transmitter unit for transmitting the first number of symbols.

19. The apparatus as in claim 18, wherein the first number of symbols is two, the first orthogonal cover is {1, 1}, and the second orthogonal cover is {1, −

1}.

20. The apparatus as in claim 18, wherein the communication system comprises a single-carrier frequency domain multiple access communication system.