Fast feedback channel with flexible bit reliability for wireless communications
View Patent ↗A single physical channel carries “fast feedback” information in such a way that each type of data is on a physical sub-channel. The sub-channels are not “logical” channels in that they cannot be separated by logical functions alone because some knowledge of the modulation mechanisms is required. Each sub-channel is independently channel coded (this is outer channel coding if an inner code is applied). The resulting code symbols from all sub-channels are then merged into one set of symbols. These code symbols can then optionally be concatenation interleaved and inner channel coded, if the performance enhancement is desired and the complexity is acceptable. The result is then extended by code symbol repetition to provide a total number of symbols greater than or equal to one of the possible quantities of symbols per frame supported by the physical channel, and then decimated (symbols deleted) to provide a number of symbols equal to one of the allowable quantities of symbols per frame. The result is then interleaved, and transmitted over the physical channel.
1. A method of combining a plurality of sub-channels to form a single physical channel, comprising the steps of:
individually channel coding at least a first and a second sub-channel of the plurality of sub-channels to form respective first and second resulting code symbols;
merging the first and second resulting code symbols to form a combined set of symbols;
interleaving the combined set of symbols so that the combined set of symbols can be transmitted over the single physical channel.
2. The method as set forth in claim 1 comprising the step of concatenation interleaving the combined set of symbols to form a concatenation interleaved set.
3. The method as set forth in claim 2 comprising the step of inner coding the concatenation interleaved set to form an inner coded set.
4. The method as set forth in claim 1 comprising the step of extending the combined set of symbols by code symbol repetition to form an extended symbol set.
5. The method as set forth in claim 4 comprising the step of decimating the extended symbol set to attain an allowable quantity of symbols per frame.
6. The method as set forth in claim 1 wherein a third sub-channel of the plurality of sub-channels is individually channel coded to form third resulting code symbols and the third resulting code symbols are combined with the first and second resulting code symbols to form the combined set of symbols.
7. The method as set forth in claim 6 wherein the third sub-channel can be turned “on” and “off” such that:
when “on”, the third resulting code symbols are combined with the first and second resulting code symbols to form the combined set of symbols; and
when “off”, the third resulting code symbols are not combined with the first and second resulting code symbols to form the combined set of symbols.
8. The method as set forth in claim 1 comprising the step of transmitting the combined set of symbols over the single physical channel.
9. The method as set forth in claim 8 comprising the step of receiving the combined set of symbols over the single physical channel and separating the combined set into the first and second sub-channels.
10. The method as set forth in claim 1 wherein the sub-channels cannot be separated from the combined set of symbols by logical functions without modulation mechanism knowledge.
11. An apparatus that recovers data transmitted on the first and second sub-channels that have been combined according to the method as set forth in claim 1 .
12. The method as set forth in claim 1 wherein the first sub-channel carries data selected from the group consisting of:
transmit sector indication information;
power control indication information;
fast frame acknowledgment information;
signal-to-noise ratio (SNR) indication information;
data rate information; and
adaptive antenna array information.
13. An apparatus to combine a plurality of sub-channels to form a single physical channel, comprising:
a first channel coder to individually channel code a first sub-channel of the plurality of sub-channels to form first resulting code symbols;
a second channel coder to individually channel code a second sub-channel of the plurality of sub-channels to form second resulting code symbols;
an interleaver to merge the first and second resulting code symbols to form a combined set of symbols and to interleave the combined set of symbols so that the combined set of symbols can be transmitted over the single physical channel.
14. The apparatus as set forth in claim 13 comprising a concatenation interleaver to interleave the combined set of symbols to form a concatenation interleaved set.
15. The apparatus as set forth in claim 14 comprising an inner coder to inner code the concatenation interleaved set to form a inner coded set.
16. The apparatus as set forth in claim 13 comprising rate matching symbol repeater to extend the combined set of symbols by code symbol repetition to form an extended symbol set.
17. The apparatus as set forth in claim 16 comprising a decimator to decimate the extended symbol set to substantially match an allowable quantity of symbols per frame.
18. The apparatus as set forth in claim 13 comprising a third channel coder to individually channel code a third sub-channel of the plurality of sub-channels to form third resulting code symbols and wherein the third resulting code symbols are combined with the first and second resulting code symbols to form the combined set of symbols.
19. The apparatus as set forth in claim 18 wherein the third sub-channel can be turned “on” and “off” such that:
when “on”, the third resulting code symbols are combined with the first and second resulting code symbols to form the combined set of symbols; and
when “off”, the third resulting code symbols are not combined with the first and second resulting code symbols to form the combined set of symbols.
20. The apparatus as set forth in claim 13 comprising a transmitter to transmit the combined set of symbols over the single physical channel.