MULTIPLE-OUTPUT TRANSMITTER FOR TRANSMITTING A PLURALITY OF SPATIAL STREAMS

• US 20090279629A1
• Filed: 07/20/2009
• Published: 11/12/2009
• Est. Priority Date: 11/16/2004
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Chimitt, William J., Ling, Stanley K., Sandhu, Sumeet
• Granted Patent: US 7,899,128 B2
• Time in Patent Office: Days
• US Class Current: 375/261
• CPC Class Codes: H04B 7/0669 using different channel coding between antennas space-time coding H04L1/0618
• CPC Class Codes: H04B 7/0697 using spatial multiplexing
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 27/2626 Arrangements specific to the transmitter only
• CPC Class Codes: H04L 5/0044 allocation of payload

Abstract

A multiple output transmitter is configured for transmitting a single input data stream over two or more spatial channels using OFDM signals. The transmitter includes a commutator to select bits from the single input data stream for two or more bit streams and two or more encoders each to encode bits of one of the bit streams. The commutator operates at a bit rate and sequentially provides the selected bits of the input data stream to the encoders. A spatial bit sequencer selects groups of encoded bits from each of the encoders and assigns individual bits of a selected group at the bit-rate to block permuters in a sequential manner to distribute bits from the selected group across the block permuters. The block permuters produce interleaved blocks of bits for an associated spatial stream. The commutator assigns bits of the input bit stream to more than one encoder to allow each encoder to operate at a lower rate.

Claims

1. A transmitter configured for transmitting a single input data stream over two or more spatial channels using orthogonal frequency division multiplexed (OFDM) signals, the transmitter comprising:

a commutator to select bits from the single input data stream for two or more bit streams;

two or more encoders, each to encode bits of one of the bit streams, wherein the commutator operates at a bit rate and sequentially provide the selected bits of the input data stream to the encoders;

a spatial bit sequencer; and

a block permuter associated with each spatial stream, the spatial bit sequencer to select groups of encoded bits from each of the encoders and to assign individual bits of a selected group at the bit-rate to each of the block permuters in a sequential manner to distribute bits from the selected group across the block permuters, the block permuters to perform a block interleaving operation on blocks of bits of an associated spatial stream to produce interleaved blocks of bits for the associated spatial streams.

2. The transmitter of claim 1 wherein the commutator assigns bits of the input bit stream to more than one encoder to allow each encoder to operate at a lower rate.

3. The transmitter of claim 2 further comprising a QAM mapper for each spatial stream to map bits of the spatial streams to QAM symbols for subsequent transmission.

4. The transmitter of claim 3 further comprising:

bit-grouping shifters to shift bits within symbol-bit groupings of the interleaved blocks of bits by a spatial stream index of an associated spatial stream, each spatial stream having a different spatial stream index; and

bit-position permuters to rotate bits among I and Q subgroups of the symbol-bit groupings based on the spatial stream index.

5. The transmitter of claim 4 wherein the spatial stream index is zero for a first spatial stream, one for a second spatial stream, two for a third spatial stream and three for a forth spatial stream.

6. The transmitter of claim 5 further comprising transmission circuitry to transmit the QAM symbols for each of the spatial streams over an associated spatial channel,

wherein the transmission circuitry is configured to transmit the OFDM symbols in accordance with an IEEE 802.16 communication standard.

7. The transmitter of claim 6 wherein the transmitter comprises four of the encoders, four of the block permuters and four of the QAM mappers for transmitting the single input data stream over up to four of the spatial channels,

wherein the commutator select bits from the single input data stream for four bit streams, and

wherein the spatial bit sequencer operates at one-fourth the bit rate to select groups of the encoded bits from each of the four encoders.

8. A method for transmitting a single input data stream over two or more spatial channels using orthogonal frequency division multiplexed (OFDM) signals with a transmitter, the method comprising:

selecting bits from the single input data stream for two or more bit streams;

separately encoding bits of each of the bit streams wherein the bits are selected at a bit rate and sequentially provided for encoding by separate encoders;

selecting groups of encoded bits from each of the encoders and assigning individual bits of a selected group at the bit-rate to block permuters in a sequential manner to distribute bits from the selected group across the block permuters,

performing a block interleaving operation on blocks of bits of an associated spatial stream to produce interleaved blocks of bits for the associated spatial streams.

9. The method of claim 8 wherein the bits of the input bit stream are assigned to more than one encoder to allow each encoder to operate at a lower rate.

10. The method of claim 9 further comprising mapping, with a QAM mapper for each spatial stream, bits of the spatial streams to QAM symbols for subsequent transmission.

11. The method of claim 10 further comprising:

shifting bits within symbol-bit groupings of the interleaved blocks of bits by a spatial stream index of an associated spatial stream, each spatial stream having a different spatial stream index; and

rotating bits among I and Q subgroups of the symbol-bit groupings based on the spatial stream index.

12. The method of claim 11 wherein the spatial stream index is zero for a first spatial stream, one for a second spatial stream, two for a third spatial stream and three for a forth spatial stream.

13. The method of claim 12 further comprising transmitting the QAM symbols for each of the spatial streams over an associated spatial channel,

wherein the transmissions of the OFDM symbols are in accordance with an IEEE 802.16 communication standard.

14. A transmitter configured for transmitting a single input data stream over two or more spatial channels using orthogonal frequency division multiplexed (OFDM) signals, the transmitter comprising:

a block permuter associated with each spatial stream;

a spatial bit sequencer to select groups of encoded bits from each of two or more encoders and to assign individual bits of a selected group at a bit-rate to each of the block permuters in a sequential manner to distribute bits from the selected group across the block permuters, the block permuters to perform a block interleaving operation on blocks of bits of an associated spatial stream to produce interleaved blocks of bits for the associated spatial streams;

bit-grouping shifters to shift bits within symbol-bit groupings of the interleaved blocks of bits by a spatial stream index of an associated spatial stream, each spatial stream having a different spatial stream index; and

bit-position permuters to rotate bits among I and Q subgroups of the symbol-bit groupings based on the spatial stream index.

15. The transmitter of claim 14 further comprising:

a commutator to select bits from the single input data stream for two or more bit streams;

the two or more encoders, each to encode bits of one of the bit streams, wherein the commutator operates at the bit rate and sequentially provides the selected bits of the input data stream to the encoders,

wherein the commutator assigns bits of the input bit stream to more than one encoder to allow each encoder to operate at a lower rate.