Radio base station and user equipment and methods therein

• US 8,638,880 B2
• Filed: 01/18/2011
• Issued: 01/28/2014
• Est. Priority Date: 01/18/2010
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Baldemair, Robert, Astely, David, Gerstenberger, Dirk, Larsson, Daniel, Parkvall, Stefan
• Primary Examiner(s): Singh, Hirdepal
• Application Number:
  US13/119,504
• Publication Number:
  US 20110261858A1
• Time in Patent Office: 1,106 Days
• Field of Search: 375/219, 375/259, 375/260, 375/263, 375/267, 375/268, 375/271, 375/295, 375/302, 375/303, 375/308, 375/316, 375/329, 375/347
• US Class Current: 375/308
• CPC Class Codes: H04J 11/0033 by pre-cancellation of known interference, e.g. using a matched filter, dirty paper coder or Thomlinson-Harashima precoder correlative coding in synchronous or start-stop systems H04L25/497
• CPC Class Codes: H04J 11/005 of intercell interference
• CPC Class Codes: H04L 5/0019 in which one code is applied, as a temporal sequence, to all frequencies
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network

Abstract

Embodiments herein include a method in a user equipment (UE) for transmitting uplink control information in time slots of a subframe over a radio channel to a radio base station. The uplink control information is comprised in a block of bits.

The UE maps the block of bits to a sequence of complex valued modulation symbols. The UE block spreads the sequence across Discrete Fourier Transform Spread-Orthogonal Frequency Division Multiplexing (DFTS-OFDM) symbols. This is performed by applying a spreading sequence to the sequence of complex valued modulation symbols, to achieve a block spread sequence of complex valued modulation symbols. The UE further transforms the block-spread sequence, per DFTS-OFDM symbol. This is performed by applying a matrix that depends on a DFTS-OFDM symbol index and/or slot index to the block-spread sequence. The UE also transmits the block spread sequence, as transformed, over the radio channel to the radio base station.

Claims

1. A method in a user equipment for transmitting uplink control information in time slots of a subframe over a radio channel to a radio base station, wherein the user equipment and radio base station are comprised in a radio communications network, wherein the radio channel is configured to carry the uplink control information, wherein the uplink control information is comprised in a block of bits, and wherein the method comprises:

mapping the block of bits to a sequence of complex valued modulation symbols,

block spreading the sequence of complex valued modulation symbols across Discrete Fourier Transform Spread-Orthogonal Frequency Division Multiplexing (DFTS-OFDM) symbols by applying a spreading sequence to the sequence of complex valued modulation symbols, to achieve a block spread sequence of complex valued modulation symbols,

transforming, per DFTS-OFDM symbol, the block-spread sequence of complex valued modulation symbols by applying a matrix to the block-spread sequence of complex valued modulation symbols, wherein the matrix comprises matrix elements that are cyclically shifted depending on at least one of a DFTS-OFDM symbol index and a slot index, and

transmitting the block spread sequence of complex valued modulation symbols, as transformed, over the radio channel to the radio base station.

2. The method according to claim 1, wherein the matrix corresponds to a Discrete Fourier Transformation operation, together with a cyclic shift operation, of rows or columns of matrix elements.

3. The method according to claim 1, further comprising

error correction encoding the block of bits, and

scrambling the block of bits before mapping the block of bits to the sequence of complex valued modulation symbols.

4. The method according to claim 1, further comprising OFDM modulating, per DFTS-OFDM symbol, the block spread sequence of complex valued modulation symbols, as transformed.

5. The method according to claim 1, wherein said transmitting comprises transmitting a first part of the sequence of complex valued modulation symbols in a first time slot and a second part of the sequence of complex valued modulation symbols in a second time slot.

6. The method according to claim 1, wherein the block of bits corresponds to uplink control information and comprises jointly encoded acknowledgements and non-acknowledgements.

7. A method in a radio base station for receiving uplink control information in time slots of a subframe over a radio channel from a user equipment, wherein the radio channel is configured to carry uplink control information, wherein the uplink control information is comprised in a block of bits, wherein the user equipment and radio base station are comprised in a radio communications network, and wherein the method comprises:

receiving a sequence of complex valued modulation symbols,

Orthogonal Frequency Division Multiplexing (OFDM) demodulating the sequence of complex valued modulation symbols,

transforming, per Discrete Fourier Transform Spread (DFTS)-OFDM symbol, the OFDM demodulated sequence of complex valued modulation symbols by applying a matrix to that OFDM demodulated sequence, wherein the matrix comprises matrix elements that are cyclically shifted depending on at least one of a DFTS-OFDM symbol index and a slot index,

block despreading the OFDM demodulated sequence of complex valued modulation symbols, as transformed, with a despreading sequence, and

mapping the despread sequence of complex valued modulation symbols to a block of bits.

8. A user equipment for transmitting uplink control information in time slots of a subframe over a radio channel to a radio base station, wherein the radio channel is configured to carry uplink control information, wherein the uplink control information is comprised in a block of bits, and wherein the user equipment comprises

a mapping circuit configured to map the block of bits to a sequence of complex valued modulation symbols,

a block spreading circuit configured to block spread the sequence of complex valued modulation symbols across Discrete Fourier Transform Spread-Orthogonal Frequency Division Multiplexing (DFTS-OFDM) symbols by applying a spreading sequence to the sequence of complex valued modulation symbols, to achieve a block spread sequence of complex valued modulation symbols,

a transforming circuit configured to transform, per DFTS-OFDM symbol, the block-spread sequence of complex valued modulation symbols by applying a matrix to the block-spread sequence of complex valued modulation symbols, wherein the matrix comprises matrix elements that are cyclically shifted depending on at least one of a DFTS-OFDM symbol index and a slot index, and

a transmitter configured to transmit the block spread sequence of complex valued modulation symbols, as transformed, over the radio channel to the radio base station.

9. The user equipment according to claim 8, wherein the matrix corresponds to a Discrete Fourier Transformation operation, together with a cyclic shift operation, of rows or columns of matrix elements.

10. The user equipment according to claim 8, further comprising

an error correction coding circuit configured to error correction encode the block of bits, and

a scrambling circuit configured to scramble the block of bits before mapping the block of bits to the sequence of complex valued modulation symbols.

11. The user equipment according to claim 8, further comprising an OFDM modulator configured to OFDM modulate, per DFTS-OFDM symbol, the block spread sequence of complex valued modulation symbols, as transformed.

12. The user equipment according to claim 8, wherein the transmitter is configured to transmit a first part of the sequence of complex valued modulation symbols in a first time slot and a second part of the sequence of complex valued modulation symbols in a second time slot.

13. The user equipment according to claim 8, wherein the block of bits corresponds to uplink control information and comprises jointly encoded acknowledgements and non-acknowledgements.

14. A radio base station for receiving uplink control information in time slots of a subframe over a radio channel from a user equipment, wherein the radio channel is configured to carry uplink control information, wherein the uplink control information is comprised in a block of bits, and wherein the radio base station comprises:

a receiver configured to receive a sequence of complex valued modulation symbols,

an Orthogonal Frequency Division Multiplexing (OFDM) demodulating circuit configured to OFDM demodulate the sequence of complex valued modulation symbols,

a transforming circuit configured to transform, per Discrete Fourier Transform Spread (DFTS)-OFDM symbol, the OFDM demodulated sequence of complex valued modulation symbols by applying a matrix to that OFDM demodulated sequence, wherein the matrix comprises matrix elements that are cyclically shifted depending on at least one of a DFTS-OFDM symbol index and a slot index,

a block despreading circuit configured to block despread the OFDM demodulated sequence of complex valued modulation symbols, as transformed, with a despreading sequence, and

a mapping circuit configured to map the despread sequence of complex valued modulation symbols to a block of bits.

15. A method in a terminal for transmitting uplink control information in a slot of a subframe over a channel to a base station in a wireless communication system, wherein the uplink control information is comprised in a code word, and wherein the method comprises:

mapping the code word to modulation symbols;

block spreading the modulation symbols across Discrete Fourier Transform Spread-Orthogonal Frequency Division Multiplexing (DFTS-OFDM) symbols by repeating the modulation symbols for each DFTS-OFDM symbol and applying a block spreading sequence of weight factors to the repeated modulation symbols, to achieve a respective weighted copy of the modulation symbols for each DFTS-OFDM symbol;

transforming, for each DFTS-OFDM symbol, the respective weighted copy of the modulation symbols by applying a matrix to the respective weighted copy of the modulation symbols, wherein the matrix comprises matrix elements that are cyclically shifted depending on at least one of a DFTS-OFDM symbol index and a slot index; and

transmitting, on each DFTS-OFDM symbol, the respective weighted copy of the modulation symbols, as transformed, to the base station.

16. The method according to claim 15, wherein the channel is a Physical Uplink Control Channel.

17. The method according to claim 15, wherein the code word is a number of bits.

18. The method according to claim 15, wherein the modulation symbols are Quadrature Phase-Shift Keying symbols or Binary Phase-Shift Keying symbols.

19. The method according to claim 15, wherein the block spreading sequence is an orthogonal sequence.

20. The method according to claim 15, wherein said transforming comprises cyclically shifting rows or columns of the matrix, and wherein the matrix is a Discrete Fourier Transform matrix.