System and method for allocating transmission resources

1. A method thr wirelessly transmitting user data and control information using a plurality of transmission layers, comprising:

determining a total amount of transmission resources granted to a wireless terminal for use in a subframe based on a product of a total number of subcarriers allocated to a wireless terminal and a total number of vector symbols allocated to the wireless terminal;

estimating a number of vector symbols to be allocated by the wireless terminal to a plurality of user data codewords based on the total amount of transmission resources granted to the wireless terminal for use in the subframe;

determining a number of bits in one or more the plurality of user data codewords to be transmitted by the wireless terminal during the subframe;

calculating a number of control vector symbols to allocate to control information based at least in part on the estimated number of vector symbols and the determined number of bits;

mapping one or more control codewords to the calculated number of control vector symbols, wherein the one or more control codewords comprise encoded control information; and

transmitting vector symbols carrying the user data codewords and the control codewords over the plurality of transmission layers during the subframe.

2. The method of claim 1 , wherein determining the number of bits in one or more of a plurality of user data codewords comprises calculating a total number of bits in all of the user data codewords to be transmitted during the subframe.

3. The method of claim 1 , wherein the calculated number of control vector symbols is inversely proportional to a total number of hits in all of the user data codewords to be transmitted during the subframe.

4. The method of claim 1 , wherein determining the number of bits in one or more of the plurality of user data codewords comprises calculating a total number of bits in a subset of user data codewords to be transmitted by the wireless terminal during the subframe.

5. The method of claim 4 , wherein calculating the total number of bits in a subset of the user data codewords comprises:

identifying the transmission layers over which control codewords will be transmitted during the subframe; and

calculating the total number of bits in a subset of the user data codewords that will be transmitted over the identified transmission layers.

6. The method of claim 1 , wherein calculating the number of control vector symbols to allocate to control information Comprises:

determining a number of transmission layers over which the codewords of user data will be transmitted; and

calculating the number of control vector symbols to allocate to control information based, at least in part, on the estimated number of vector symbols, the determined number of bits, and the determined number of layers.

7. The method of claim 1 , wherein calculating the number of control vector symbols to allocate to control information comprises:

determining a nominal number of control vector symbols to allocate to control information based, at least in part, on the estimated number of vector symbols and the determined number of bits; and

determining a final number of control vector symbols by multiplying the nominal number of control vector symbols and an offset value; and wherein mapping one or more control codewords to the calculated number of control vector symbols comprises mapping the one or more control codewords to the final number of control vector symbols.

8. The method of claim 1 , wherein calculating the number of control vector symbols to allocate to control information comprises:

determining a nominal number of control vector symbols to allocate to control information based, at least in part, on the estimated number of vector symbols and the determined number of bits; and

determining a final number of control vector symbols by selecting the greater of the nominal number of control vector symbols and a minimum number of control vector symbols.

9. The method of claim 1 , wherein calculating a number of control vector symbols to allocate to control information comprises:

determining, for each of the user data codewords, a payload-per-layer value by dividing a number of bits in that user data codeword by a number of layers over which that user data codeword will be transmitted; and

selecting a lowest of the payload-per-layer values for the plurality of user data codewords; and

determining a number of control vector symbols to allocate to control information based on the estimated number of vector symbols and the lowest of the payload-per-layer values for the user data codewords.

10. The method of claim 9 , wherein the calculated number of control vector symbols is inversely proportional to the lowest of the payload-per-layer values.

11. The method of claim 1 , wherein the vector symbols each comprise an information element associated with each transmission layer over which the wireless terminal will transmit in the subframe.

12. The method of claim 1 , wherein calculating the number of control vector symbols to allocate to control information comprises calculating a number of control vector symbols that is proportional to a product of:

the estimated number of vector symbols;

the determined number of bits; and

an offset value.

13. A method for receiving user data and control information transmitted wirelessly over a plurality of transmission layers, comprising:

receiving a plurality of vector symbols from a wireless terminal over a plurality of transmission layers during a subframe, wherein the vector symbols carry user data codewords and control codewords;

determining a total amount of transmission resources granted to the wireless terminal for use in the subframe based on a product of a total number of subcarriers allocated to the wireless terminal and a total number of vector symbols allocated to the wireless terminal;

estimating a number of vector symbols that have been allocated to a plurality of user data codewords based on the total amount of transmission resources granted to the wireless terminal for use in the subframe;

determining a number of bits in one or more of the plurality of user data codewords carried by the received vector symbols;

calculating a number of control vector symbols that have been allocated to control information based at least in part on the estimated number of vector symbols and the determined number of bits; and

decoding the received vector symbols based on the calculated number of control vector symbols.

14. The method of claim 13 , wherein determining the number of bits in one or more of the plurality of user data codewords carried by the vector symbols comprises calculating a total number of bits in all of the user data codewords transmitted by the wireless terminal during the subframe.

15. The method of claim 13 , wherein the calculated number of control vector symbols is inversely proportional to a total number of bits in all of the user data codewords transmitted by the wireless terminal during the subframe.

16. The method of claim 13 , wherein determining, the number of bits in one or more the plurality of user data codewords carried by the vector symbols comprises calculating a total number of bits in a subset of the user data codewords transmitted by the wireless terminal during the subframe.

17. The method of claim 16 , wherein calculating the total number of bits in a subset of the received user data codewords comprises:

identifying the transmission layers over which control codewords were received; and

calculating the total number of bits in a subset of the user data codewords were received over the identified transmission layers.

18. The method of claim 13 , wherein calculating the number of control vector symbols that have been allocated to control information comprises:

determining a number of transmission layers over which the codewords of user data have been received; and

calculating the number of control vector symbols that have been allocated to control information based, at least in part, on the estimated number of vector symbols, the determined number of bits, and the determined number of layers.

19. The method of claim 13 , wherein calculating the number of control vector symbols that have been allocated to control information comprises:

determining a nominal number of control vector symbols based, at least in part, on the estimated number of vector symbols and the determined number of bits; and

determining a final number of control vector symbols that have been allocated to control information by multiplying the nominal number of control vector symbols and an offset value; and wherein decoding the received vector symbols based on the calculated number of control vector symbols comprises decoding control information carried by a number of control vector symbols equal to the final number.

20. The method of claim 13 , wherein calculating the number of control vector symbols that have been allocated to control information comprises:

determining a nominal number of control vector symbols based, at least in part, on the estimated number of vector symbols and the determined number of bits; and

determining a final number of control vector symbols that have been allocated to control information by selecting the greater of the nominal number of control vector symbols and a minimum number of control vector symbols.

21. The method of claim 13 , wherein calculating a number of control vector symbols that have been allocated to control information comprises:

determining, for each of the user data codewords, a payload-per-layer value by dividing a number of bits in that user data codeword by a number of layers over which that user data codeword was received;

selecting a lowest of the payload-per-layer values for the plurality of user data codewords; and

determining a number of control vector symbols that have been allocated to control information based on the estimated number of vector symbols and the lowest of the payload-per-layer values for the user data codewords.

22. The method of claim 21 , wherein the calculated number of control vector symbols is inversely proportional to the lowest of the payload-per-layer values.

23. The method of claim 13 , wherein the vector symbols each comprise an information element associated with each transmission layer over which the wireless terminal will transmit in the subframe.

24. The method of claim 13 , wherein calculating the number of control vector symbols that have been allocated to control information comprises calculating a number of control vector symbols that is proportional to a product of:

the estimated number of vector symbols

the determined number of bits; and

an offset value.

25. A method of scheduling wireless transmissions over a plurality of transmission layers, comprising:

receiving a scheduling request from a transmitter requesting use of transmission resources to transmit a plurality of vector symbols;

determining a transmission rank, a total number of vector symbols to be used for user data and control information, and a number of bits of user data to be carried by each of the user data codewords, accounting, at least in part, for an estimated number of control vector symbols, wherein the estimated number of control vector symbols is determined by:

determining a total amount of transmission resources to be granted to the transmitter based on a product of a total number of subcarriers to be used by the transmitter and the determined total number of vector symbols;

estimating a number of user data vector symbols to be allocated to a plurality of user data codewords based on the total amount of transmission resources granted to the transmitter;

estimating a number of bits in one or more control codewords to be transmitted, wherein the one or more control codewords comprise encoded control information; and

calculating the estimated number of control vector symbols to be used in transmitting the control codewords based at least in part, on the estimated number of user data vector symbols to be used in transmitting the user data codewords, the estimated number of bits in the one or more control codewords, and the number of bits of user data to be carried by each of the user data codewords;

generating a response to the scheduling request based on the determined transmission rank, total number of vector symbols, and number of bits of each user data codeword; and

transmitting the response to the transmitter.

26. An apparatus for wirelessly transmitting user data and control information using a plurality of transmission layers, the apparatus comprising:

a plurality of antennas;

a transmitter configured to transmit vector symbols over a plurality of transmission layers using the plurality of antennas; and

electronic circuitry configured to:

determine a total amount of transmission resources granted to a wireless terminal for use in a subframe based on a product of a total number of subcarriers allocated to a wireless terminal for use in a subframe and a total number of vector symbols allocated to the wireless terminal for use in the subframe;

estimate a number of vector symbols to be allocated to a plurality of user data codewords based on the total amount of transmission resources granted to the wireless terminal for use in the subframe;

determine a number of bits in one or more of a plurality of user data codewords to be transmitted during the subframe;

calculate a number of control vector symbols to allocate to control information based at least in part on the estimated number of vector symbols and the determined number of bits;

map one or more control codewords to the calculated number of control vector symbols, wherein the one or more control codewords comprise encoded control information; and

transmit vector symbols carrying the user data codewords and the control codewords over the plurality of transmission layers during the subframe using the transmitter.

27. A node for receiving user data and control information transmitted wirelessly over a plurality of transmission layers, the node comprising:

a plurality of antennas;

a receiver configured to transmit vector symbols over a plurality of transmission layers using the plurality of antennas; and

electronic circuitry configured to:

receive a plurality of vector symbols from a wireless terminal over a plurality of transmission layers during a subframe using the receiver, wherein the vector symbols carry user data codewords and control codewords;

determine a total amount of transmission resources granted to the wireless terminal for use in the subframe based on a product of a total number of subcarriers allocated to the wireless terminal and a total number of vector symbols allocated to the wireless terminal;

estimate a number of vector symbols that have been allocated to transmission of a plurality of user data codewords based on the total amount of transmission resources granted to the wireless terminal for use in the subframe;

determine a number of bits in one or more of the plurality of user data codewords carried by the vector symbols;

calculate a number of control vector symbols that have been allocated to control information based at least in part on the estimated number of vector symbols and the determined number of bits; and

decode the received vector symbols based on the calculated number of control vector symbols.

28. A node for scheduling wireless transmissions over a plurality of transmission layers, the node comprising:

a receiver operable to receive information from wireless terminal;

a transmitter operable to transmit information to the wireless terminal; and

a processor operable to:

receive a scheduling request from the wireless terminal using the receiver, the scheduling request requesting use of transmission resources to transmit a plurality of vector symbols;

determine a transmission rank, a total number of vector symbols to be used for user data and control information, and a number of bits of user data to be carried by each of the user data codewords, accounting, at least in part, for an estimated number of control vector symbols, wherein the processor is operable to determine the estimated number of control vector symbols by:

determine a total amount of transmission resources to be granted to the wireless terminal based on a product of a total number of subcarriers to be used by the wireless terminal and the determined total number of vector symbols;

estimate a number of user data vector symbols to be allocated to a plurality of user data codewords based on the total amount of transmission resources granted to the wireless terminal;

estimating a number of bits in one or more control codewords to be transmitted, wherein the one or more control codewords comprise encoded control information; and

calculating the estimated number of control vector symbols to be used in transmitting the control codewords based at least in part on the estimated number of user data vector symbols to be used in transmitting the user data codewords, the estimated number of bits in the one or more control codewords, and the number of bits of user data to be carried by each of the user data codewords;

generate a response to the scheduling request based on the determined transmission rank, total number of vector symbols, and number of hits of each user data codeword; and

transmit the response to the wireless terminal using the transmitter.