Wireless precoding methods
View Patent ↗Various wireless precoding systems and methods are presented. In some embodiments, a wireless transmitter comprises an antenna precoding block, a transform block, and multiple transmit antennas. The antenna precoding block receives frequency coefficients from multiple data streams and distributes the frequency coefficients across multiple transmit signals in accordance with frequency-dependent matrices. The transform block transforms the preceded frequency coefficients into multiple time domain transmit signals to be transmitted by the multiple antennas. The frequency coefficients from multiple data streams may be partitioned into tone groups, and all the frequency coefficients from a given tone group may be redistributed in accordance with a single matrix for that tone group. In some implementations, the frequency coefficients within a tone group for a given data stream may also be precoded. In some alternative embodiments, tone group preceding may be employed in a single channel system.
1. A wireless transmitter comprising:
tone group precoding matrix blocks having inputs coupled to outputs of bit allocation blocks and having outputs, the tone group precoding matrix blocks distributing signal energy across the tone groups for each of the multiple data streams to distribute the data bits across multiple tones;
antenna precoding matrix blocks having inputs coupled to the outputs of the tone group precoding matrix blocks and having outputs, the antenna precoding matrix blocks being applied to the tones; and
inverse fast Fourier Transform and parallel to serial blocks having inputs coupled to the outputs of the antenna precoding matrix blocks.
2. The wireless transmitter of claim 1 in which there is a separate antenna precoding matrix block for each tone.
3. The wireless transmitter of claim 1 in which there is one antenna precoding matrix block for a group of tones.
4. The wireless transmitter of claim 1 in which 256 available tones are divided into 32 groups of 8 tones each and there are 32 antenna precoding matrix blocks, one for each group.
5. The wireless transmitter of claim 1 in which the tone group precoding matrix blocks distribute signal energy equally across the tone groups for each of the multiple data streams.
6. The wireless transmitter of claim 1 in which the antenna precoding matrix blocks are applied to the tones to distribute the energy of the tones equally across the outputs of the antenna precoding matrix blocks.
7. The wireless transmitter of claim 1 in which the tone group precoding matrix blocks, and antenna precoding matrix blocks are free of feedback from a receiver.
8. A wireless transmitter comprising:
tone group precoding matrix blocks having inputs coupled to outputs of bit allocation blocks and having outputs, the tone group precoding matrix blocks distributing signal energy across the tone groups for each of the multiple data streams to distribute the data bits across multiple tones;
an antenna precoding matrix block having inputs coupled to the outputs of the tone group precoding matrix blocks and having outputs, the antenna precoding matrix block being applied to the tones; and
inverse fast Fourier Transform and parallel to serial blocks having inputs coupled to the outputs of the antenna precoding matrix block.
9. The wireless transmitter of claim 8 in which 256 available tones are divided into 32 groups of 8 tones each and there are 32 antenna precoding matrix blocks, one for each group.
10. The wireless transmitter of claim 8 in which the tone group precoding matrix blocks distribute signal energy equally across the tone groups for each of the multiple data streams.
11. The wireless transmitter of claim 8 in which the antenna precoding matrix blocks are applied to the tones to distribute the energy of the tones equally across the outputs of the antenna precoding matrix blocks.
12. The wireless transmitter of claim 8 in which the tone group precoding matrix blocks, and antenna precoding matrix blocks are free of feedback from a receiver.
13. The method of claim 8 in which there is a separate antenna preceding matrix block for each tone.
14. A method, comprising:
receiving at least one data stream;
apportioning data bits from the at least one data stream among available tones;
outputting a quadrature amplitude modulation (QAM) constellation signal point for each tone;
distributing signal energy across the tone groups for the at least one data stream to distribute the data bits across multiple tones; and
distributing the data bits across multiple antennas.
15. The method of claim 14 in which there is one antenna precoding matrix block for a group of tones.
16. The method of claim 14 in which 256 available tones are divided into 32 groups of 8 tones each and there are 32 antenna precoding matrix blocks, one for each group.
17. The method of claim 14 in which the tone group precoding matrix blocks distribute signal energy equally across the tone groups for each of the multiple data streams.
18. The wireless transmitter of claim 14 in which the antenna precoding matrix blocks are applied to the tones to distribute the energy of the tones equally across the outputs of the antenna precoding matrix blocks.
19. The method of claim 14 in which the tone group precoding matrix blocks, and antenna precoding matrix blocks are free of feedback from a receiver.