# US 9,521,019 B2 · Efficient uplink feedback in a wireless communication system

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- Number: US 9,521,019 B2
- Document ID: US9521019B2
- Status: Granted
- Kind: B2
- Application number: 13/663,809
- Filed: 2012-10-30
- Published: 2013-03-14
- Granted: 2016-12-13
- Earliest claimed: 2007-03-21
- Assignees: Samsung Electronics Co., Ltd.
- Applicants: Samsung Electronics Co., Ltd.
- Inventors: Farooq Khan; Zhouyue Pi
- Web page: https://patentgrep.com/patent/US9521019B2

## CPC

- H04L 25/03343: {Arrangements at the transmitter end}
- H04L 2025/03414: {Multicarrier}
- H04L 2025/03426: {transmission using multiple-input and multiple-output channels}
- H04L 2025/03802: {Signalling on the reverse channel}
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)

## Abstract

A method for transmitting control information by transmitting a reference signal from a first transceiver to a second transceiver, in response to the reception of the reference signal, determining at the second transceiver a plurality of control channel elements based upon the received reference signal, jointly encoding the plurality of control channel elements at the second transceiver to generate a control signal, and transmitting the control signal from the second transceiver to the first transceiver.

## Claims

### Claim 1

A method for transmitting control information by a user equipment (UE), the method comprising:
receiving a reference signal from a first transceiver;
in response to the reception of the reference signal, determining a plurality of control information based upon the received reference signal;
jointly encoding the plurality of control information using a block code;
modulating the encoded control information to generate a plurality of modulated symbols using a modulation scheme;
multiplying a selected sequence with the modulated symbols to generate a plurality of multiplied sequences;
mapping the plurality of multiplied sequences into two sets of resource elements in time and frequency domains in a subframe, the two sets of resource elements allocated to the UE,
a first set of the two sets of resource elements being located in one edge of the subframe in the frequency domain and in a first half of the subframe in the time domain, and
a second set of the two sets of resource elements being located in an opposite edge of the subframe in the frequency domain and in a second half of the subframe in the time domain; and
converting the mapped sequences to radio frequency signals for transmission.

### Claim 2 (depends on 1)

The method of claim 1, wherein the control information is at least one of channel quality information (CQI), a precoding matrix indication (PMI), and a rank indication (RI).

### Claim 3 (depends on 1)

The method of claim 1, wherein the modulation scheme is quadrature phase shift key (QPSK) modulation.

### Claim 4 (depends on 1)

The method of claim 1, further comprising:
applying a constant amplitude zero autocorrelation (CAZAC) sequence to the modulated symbols to generate a plurality of CAZAC-modulated sequences; and
transmitting the plurality of CAZAC-modulated sequences using a number of subcarriers,
wherein the number of subcarriers is an integer multiple of a length of the CAZAC sequence, and
wherein the length of the CAZAC sequence is 12.

### Claim 5 (depends on 1)

The method of claim 1, further comprising:
applying a constant amplitude zero autocorrelation (CAZAC) sequence to the modulated symbols to generate a plurality of CAZAC-modulated sequences; and
transmitting the plurality of CAZAC-modulated sequences using a number of subcarriers,
wherein the number of subcarriers is an integer multiple of a length of the CAZAC sequence,
wherein the plurality of CAZAC-modulated sequences are mapped into the two sets of resource elements.

### Claim 6

A user equipment (UE), comprising:
a receiver configured to receive a reference signal from a first transceiver; and
a controller configured to:
in response to the reception of the reference signal, determine a plurality of control information based upon the received reference signal,
jointly encode the plurality of control information using a block code,
modulate the encoded control information to generate a plurality of modulated symbols using a modulation scheme,
multiply a selected sequence to with the modulated symbols to generate a plurality of multiplied sequences,
map the plurality of multiplied sequences into two sets of resource elements in time and frequency domains in a subframe, the two sets of resource elements allocated to the UE,
a first set of the two sets of resource elements being located in one edge of the subframe in the frequency domain and in a first half of the subframe in the time domain, and
a second set of the two sets of resource elements being located in an opposite edge of the subframe in the frequency domain and in a second half of the subframe in the time domain, and
convert the mapped sequences to radio frequency signals for transmission.

### Claim 7 (depends on 6)

The UE of claim 6, wherein the control information is at least one of channel quality information (CQI), a precoding matrix indication (PMI), and a rank indication (RI).

### Claim 8 (depends on 6)

The UE of claim 6, wherein the modulation scheme is quadrature phase shift key (QPSK) modulation.

### Claim 9 (depends on 6)

The UE of claim 6, wherein the controller configured to:
apply a constant amplitude zero autocorrelation (CAZAC) sequence to the modulated symbols to generate a plurality of CAZAC-modulated sequences; and
cause transmission of the plurality of CAZAC-modulated sequences using a number of subcarriers,
wherein the number of subcarriers is an integer multiple of a length of the CAZAC sequence, and
wherein the length of the CAZAC sequence is 12.

### Claim 10 (depends on 6)

The UE of claim 6, wherein the controller configured to:
apply a constant amplitude zero autocorrelation (CAZAC) sequence to the modulated symbols to generate a plurality of CAZAC-modulated sequences; and
cause transmission of the plurality of CAZAC-modulated sequences using a number of subcarriers,
wherein the number of subcarriers is an integer multiple of a length of the CAZAC sequence, and
wherein the plurality of CAZAC-modulated sequences are mapped into the two sets of resource elements.

### Claim 11

A method for receiving control information from a user equipment (UE) at a base station, comprising:
transmitting a reference signal from a first transceiver; and
receiving signals from the UE at the base station, the signals generated by:
receiving the reference signal at the UE;
in response to the reception of the reference signal, determining a plurality of control information based upon the received reference signal,
jointly encoding the plurality of control information using a block code,
modulating the encoded control information to generate a plurality of modulated symbols using a modulation scheme,
multiplying a selected sequence with the modulated symbols to generate a plurality of multiplied sequences,
mapping the plurality of multiplied sequences into two sets of resource elements in time and frequency domains in a subframe, the two sets of resource elements allocated to the UE,
a first set of the two sets of resource elements being located in one edge of the subframe in the frequency domain and in a first half of the subframe in the time domain, and
a second set of the two sets of resource elements being located in an opposite edge of the subframe in the frequency domain and in a second half of the subframe in the time domain; and
converting the mapped sequences to radio frequency signals for transmission.

### Claim 12 (depends on 11)

The method of claim 11, wherein the control information is at least one of channel quality information (CQI), a precoding matrix indication (PMI), and a rank indication (RI).

### Claim 13 (depends on 11)

The method of claim 11, wherein the modulation scheme is quadrature phase shift key (QPSK) modulation.

### Claim 14 (depends on 11)

The method of claim 11, wherein the received signals are generated by:
applying a constant amplitude zero autocorrelation (CAZAC) sequence to the modulated symbols to generate a plurality of CAZAC-modulated sequences; and
transmitting the plurality of CAZAC-modulated sequences using a number of subcarriers,
wherein the number of subcarriers is an integer multiple of a length of the CAZAC sequence, and
wherein the length of the CAZAC sequence is 12.

### Claim 15 (depends on 11)

The method of claim 11, wherein the received signals are generated by:
applying a constant amplitude zero autocorrelation (CAZAC) sequence to the modulated symbols to generate a plurality of CAZAC-modulated sequences; and
transmitting the plurality of CAZAC-modulated sequences using a number of subcarriers,
wherein the number of subcarriers is an integer multiple of a length of the CAZAC sequence, and
wherein the plurality of CAZAC-modulated sequences are mapped into the two sets of resource elements.