Method and/or system for reduction of PAPR

• US 8,040,787 B2
• Filed: 12/02/2005
• Issued: 10/18/2011
• Est. Priority Date: 12/02/2004
• Status: Active Grant

• Current Assignee: New Jersey Institute of Technology
• Original Assignee: New Jersey Institute of Technology
• Inventors: Latinovic, Zoran, Bar-Ness, Yeheskel
• Primary Examiner(s): Ngo; Ricky
• Assistant Examiner(s): HAN, CLEMENCE S
• Application Number:
  US11/293,852
• Publication Number:
  US 20060245346A1
• Time in Patent Office: 2,146 Days
• Field of Search: None
• US Class Current: 370/203
• CPC Class Codes: H04B 7/02 Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas RAKE receivers H04B1/7115
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/0606 Space-frequency coding
• CPC Class Codes: H04L 1/0643 block codes
• CPC Class Codes: H04L 27/2614 Peak power aspects
• CPC Class Codes: H04L 27/2615 Reduction thereof using coding

Abstract

Methods and/or systems for reducing peak-to-average-power ratio (PAPR) may utilize rotation among transmit channels and/or inversion of polyphase sequences of sub-blocks of an orthogonal frequency-division multiplex (OFDM) sequence in a multi-input multi-output (MIMO) scheme.

Claims

1. A method of transmitting a signal comprising:

preparing an orthogonal frequency-division multiplex (OFDM) sequence for transmission using a multi-input multi-output (MIMO) scheme using space-frequency block coding (SFBC), including performing rotation among transmit channels, wherein said rotation among transmit channels comprises a shifting of one or more sub-blocks in the time domain, and phase rotation of polyphase sequences of at least some sub-blocks of said OFDM sequence, based on a peak-to-average-power ratio (PAPR) reduction criterion, to thus obtain a prepared OFDM sequence; and

transmitting the prepared OFDM sequence.

2. The method of claim 1, wherein the sub-blocks of the OFDM sequence having polyphase sequences that are channel-rotated and phase-rotated so that out of the possible combinations of channel-rotation and phase-rotation of polyphase sequences of sub-blocks that combination of channel-rotation and phase-rotation that reduces PAPR the most is selected for transmission.

3. The method of claim 1, wherein preparing further comprises performing rotation in time based on a further partition of at least one sub-block.

4. An apparatus comprising:

a transmitter employing a multi-input multi-output orthogonal frequency-division multiplex (MIMO-OFDM) scheme using space-frequency block coding (SFBC);

said transmitter adapted to transmit an OFDM sequence in which polyphase sequences of at least some sub-blocks of said OFDM sequence have been rotated among transmit channels, wherein said rotation among transmit channels comprises a shifting of one or more sub-blocks in the time domain, and phase-rotated according to a peak-to-average-power ratio (PAPR) reduction criterion, so as to reduce PAPR.

5. The apparatus of claim 4, wherein the transmitter is adapted to select the sub-blocks of the OFDM sequence having polyphase sequences that are channel-rotated and phase-rotated so that out of the possible combinations of channel-rotation and phase-rotation of polyphase sequences of sub-blocks that combination of channel-rotation and phase-rotation that reduces PAPR the most is selected for transmission.

6. The apparatus of claim 4, wherein the transmitter is adapted to perform rotation in time based on a further partition of at least one sub-block.

7. An apparatus comprising:

a computing device;

said computing device adapted to;

prepare an orthogonal frequency-division multiplex (OFDM) sequence for transmission using a multi-input multi-output (MIMO) scheme using space-frequency block coding (SFBC), including performing rotation among transmit channels, wherein said rotation among transmit channels comprises a shifting of one or more sub-blocks in the time domain, and phase-rotating of polyphase sequences of at least some sub-blocks of said OFDM sequence, based on a peak-to-average-power ratio (PAPR) reduction criterion, to thus obtain a prepared OFDM sequence; and

transmit the prepared OFDM sequence.

8. The apparatus of claim 7, wherein said computing device is adapted to select the sub-blocks of the OFDM sequence having polyphase sequences that are channel-rotated and phase-rotated so that out of the possible combinations of channel-rotation and phase-rotation of polyphase sequences of sub-blocks that combination of channel-rotation and phase-rotation that reduces PAPR the most is selected for transmission.

9. The apparatus of claim 7, wherein said computing device is further adapted to perform rotation in time based on a further partition of at least one sub-block.

10. An article comprising a non-transitory computer-readable storage medium containing instructions that, upon execution by a system, result in operations comprising:

preparing an orthogonal frequency-division multiplex (OFDM) sequence for transmission using a multi-input multi-output (MIMO) scheme using space-frequency block coding (SFBC), including performing rotation among transmit channels, wherein said rotation among transmit channels comprises a shifting of one or more sub-blocks in the time domain, and phase rotation of polyphase sequences of at least some sub-blocks of said OFDM sequence, based on a peak-to-average-power ratio (PAPR) reduction criterion, to thus obtain a prepared OFDM sequence; and

transmitting the prepared OFDM sequence.

11. The article of claim 10, wherein the sub-blocks of the OFDM sequence having polyphase sequences that are channel-rotated and phase-rotated so that out of the possible combinations of channel-rotating and phase-rotating ofpolyphase sequences of sub-blocks that combination of channel-rotating and phase-rotating that reduces PAPR the most is selected for transmission.

12. The article of claim 10, wherein preparing further comprises performing rotation in time based on a further partition of at least one sub-block.