Transmission of acknowledge/not acknowledge (ACK/NACK) bits and their embedding in the reference signal

1. A method for transmitting in a wireless cellular network, comprising:

determining a data value for an ACK/NACK status information;

mapping the data value for the ACK/NACK status information to a cyclic shift amount of a reference signal, wherein the ACK/NACK status information is embedded in the reference signal;

constructing a pre-defined base signal using orthogonal frequency-division multiplexing (OFDM) modulation, where OFDM modulation comprises mapping a constant amplitude sequence onto a set of tones;

cyclically shifting the base signal in the time-domain by the mapped cyclic shift amount representative of the data value to form a cyclic shifted base signal; and

transmitting the cyclic shifted base signal to a receiver, whereby the receiver can determine the data value by determining the shift amount, wherein the cyclic shifts are different cyclic shift of constant amplitude zero cyclic auto-correction (CAZAC) sequence with zero auto-correlation properties providing orthogonal transmissions.

2. The method of claim 1 , further comprising transmitting a channel quality indicator (CQI) in conjunction with a cyclic shifted constant amplitude zero cyclic auto-correlation (CAZAC) like sequence, whereby the receiver may use the cyclic shifted CAZAC-like sequence as a reference signal for coherent demodulation of the CQI.

3. The method of claim 1 , further comprising modifying a constant amplitude zero cyclic auto-correction (CAZAC) like sequence before cyclic shifting.

4. The method of claim 1 , wherein the data value is an acknowledge (ACK/NACK) status bit.

5. The method of claim 1 , wherein the same data value is re-transmitted a second or more times for redundancy.

6. The method of claim 5 , wherein the data value is mapped to a different cyclic shift amount that is used for the second re-transmission.

7. The method of claim 2 , further comprising:

receiving a signal at the receiver that includes the transmitted cyclic shifted constant amplitude zero cyclic auto-correlation (CAZAC) like sequence;

determining the shift amount of the transmitted cyclic shifted CAZAC-like sequence; and

extracting the data value in accordance with the shift amount.

8. The method of claim 7 , wherein determining the shift amount comprises:

demodulating the received signal with the based CAZAC-like sequence to obtain the estimated channel taps; and

estimating the shift amount based on a location of a maximum channel tap.

9. The method of claim 7 , wherein determining the shift amount comprises:

demodulating the received signal with the base CAZAC-like sequence to obtain the estimated channel taps; and

estimating the shift amount based on a maximum section energy wherein a length of the CAZAC-like sequence is divided into N sections.

10. The method of claim 7 , further comprising using the cyclic shifted CAZAC-like sequence as a reference signal for coherent demodulation of the CQI.

11. A method for transmitting in a wireless cellular network, comprising:

determining a data value for an ACK/NACK status information;

mapping the data value for the ACK/NACK status information to a cyclic shift amount of a reference signal, wherein the ACK/NACK status information is embedded in the reference signal;

forming a subframe with a plurality of symbols with certain symbols designated as reference signals (RS) symbols;

determining when an acknowledge (ACK/NACK) response is expected;

when ACK/NACK response is not expected, inserting a pre-defined reference signal in the duration of symbols designated as RS symbols;

when an ACK/NACK response is expected, embedding the ACK/NACK response in one or more of the symbols designated as RS symbols; and

transmitting the subframe to a receiver, whereby the receiver can determine the ACK/NACK in the RS symbol, when present, and also use the RS symbol for coherent demodulation of a CQI (channel quality indicator) or data, wherein a cyclic shift is different cyclic shift of constant amplitude zero cyclic auto-correction (CAZAC) sequence with zero auto-correlation properties providing orthogonal transmissions.

12. The method of claim 11 wherein the RS comprises a base constant amplitude zero cyclic auto-correction (CAZAC) like sequence and embedding the acknowledge (ACK/NACK) response comprises:

determining a data value for the ACK/NACK response;

mapping the data value to a cyclic shift amount; and

cyclic shifting the base CAZAC-like sequence by the mapped cyclic shift amount representative of the data value to form a cyclic shifted CAZAC-like sequence.

13. A user equipment (UE) device for use in a wireless cellular network, comprising:

means for forming a subframe with a plurality of symbols with certain symbols designated as reference signal (RS) symbols;

means for determining when an acknowledge (ACK/NACK) response is expected;

means for inserting an RS in the duration of symbols designated as RS symbols when ACK/NACK response is not expected;

means for determining and mapping a data value for the ACK/NACK status information to a cyclic shift amount of a reference signal, wherein the ACK/NACK status information is embedded in the reference signal;

means for embedding the ACK/NACK response in one or more of the symbols designated as RS symbols when an ACK/NACK response is expected; and

means for transmitting the subframe to a receiver, whereby the receiver can determine the ACK/NACK in the RS symbol, when present, and also use the RS symbol for coherent demodulation of a CQI (channel quality indicator) or data, wherein cyclic shift are different cyclic shift of constant amplitude zero cyclic auto-correction (CAZAC) sequence with zero auto-correlation properties providing orthogonal transmissions.

14. The UE of claim 13 wherein the RS comprises a base CAZAC-like sequence and wherein the means for embedding the ACK/NACK response comprises:

means for determining a data value for the ACK/NACK response;

means for mapping the data value to a cyclic shift amount; and

means for cyclic shifting the base CAZAC-like sequence by the mapped cyclic shift amount representative of the data value to form a cyclic shifted CAZAC-like sequence.