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Techniques to reduce transmit power required for transmission of messages from an access terminal to reduce interference to transmissions from other access terminals. In one aspect, messages to be transmitted are defined and/or coded such that they may be detected at different received signal qualit

Techniques to reduce transmit power required for transmission of messages from an access terminal to reduce interference to transmissions from other access terminals. In one aspect, messages to be transmitted are defined and/or coded such that they may be detected at different received signal qualities. The codewords may be defined having different distances to their nearest codewords. In another aspect, messages to be transmitted are assigned to different points in a signal constellation, with the points being located such that they may be received at different signal qualities. Codewords that may be received at a lower signal quality may be assigned to messages more likely to be transmitted at higher transmit power levels (e.g., when the access terminal is located further away) or to more frequently transmitted messages.

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What is claimed is: 1. In a wireless communication system, a method for transmitting a message from a first entity to a second entity, comprising: determining, at the first entity, at least one characteristic of a communication link through which a signal is received from the second entity; forming

What is claimed is: 1. In a wireless communication system, a method for transmitting a message from a first entity to a second entity, comprising: determining, at the first entity, at least one characteristic of a communication link through which a signal is received from the second entity; forming the message indicative of a state of the communication link; assigning a codeword to the message, the assigned codeword being selected from an alphabet of a plurality of codewords, a minimum distance of the assigned codeword to its nearest codeword in the alphabet being associated with the state of the communication link; and transmitting the message from the first entity to the second entity at a particular power level determined based at least in part on the message, wherein the minimum distance of the codeword is based at least in part on how frequently the message is transmitted. 2. The method of claim 1, wherein the power level is determined based at least in part on the minimum distance of the codeword. 3. The method of claim 1, wherein the power level is determined based at least in part on an expected frequency of the codeword being transmitted. 4. The method of claim 1, wherein the power level is determined based at least in part on a particular number of times the codeword is repeated for a transmission. 5. The method of claim 1, wherein the message comprises a data rate control message indicative of a rate for a data transmission requested from the second entity. 6. The method of claim 1, wherein the at least one characteristic comprises a carrier-to-noise-plus interference ratio (C/I). 7. The method of claim 5, wherein the message is selected from a plurality of data rate control messages. 8. The method of claim 1, wherein the minimum distance of the codeword is based at least in part on a signal quality of the communication link. 9. In a wireless communication system, a method for transmitting a message from a first entity to a second entity, comprising: identifying a codeword associated with the message, wherein the identified codeword is one of a plurality of codewords defined for an alphabet, and wherein at least two codewords in the alphabet have unequal distances to their nearest codewords; determining a transmit power level for the identified codeword, based at least in part on a distance of the identified codeword to its nearest codeword in the alphabet; and transmitting the identified codeword from the first entity to the second entity at the determined transmit power level, wherein the message to be transmitted is one of a plurality of possible messages, wherein the plurality of codewords in the alphabet are assigned to the plurality of possible messages in accordance with a particular assignment scheme, and wherein the plurality of codewords in the alphabet are assigned to the plurality of possible messages such that messages to be transmitted at higher transmit power levels are assigned with codewords having larger distances to their nearest codewords. 10. The method of claim 9, wherein the transmit power level for the identified codeword is determined to achieve a particular level of performance. 11. The method of claim 10, wherein the particular level of performance is approximately one percent frame error rate or better. 12. In a wireless communication system, a method for transmitting a message from a first entity to a second entity, comprising: identifying a codeword associated with the message, wherein the identified codeword is one of a plurality of codewords defined for an alphabet, and wherein at least two codewords in the alphabet have unequal distances to their nearest codewords; determining a transmit power level for the identified codeword, based at least in part on a distance of the identified codeword to its nearest codeword in the alphabet; and transmitting the identified codeword from the first entity to the second entity at the determined transmit power level, wherein the message to be transmitted is one of a plurality of possible messages, wherein the plurality of codewords in the alphabet are assigned to the plurality of possible messages in accordance with a particular assignment scheme, and wherein the plurality of codewords in the alphabet are assigned to the plurality of possible messages such that messages to be transmitted frequently are assigned with codewords having larger distances to their nearest codewords. 13. The method of claim 9, wherein the alphabet includes N codewords having minimum distances of d1 through dN, and wherein the minimum distances conform to the following: description="In-line Formulae" end="lead"d1 ≧d2≧ . . . ≧ dN-1≧dN, and d1>dN .description="In-line Formulae" end="tail" 14. The method of claim 9, wherein the message identifies a particular data rate for a data transmission requested by the first entity from the second entity. 15. The method of claim 9, wherein the first entity comprises an access terminal in the wireless communication system. 16. The method of claim 9, wherein the wireless communication system comprises a CDMA system. 17. The method of claim 9, wherein the plurality of codewords in the alphabet are associated with a plurality of points in a signal constellation, and wherein at least two points in the signal constellation have unequal distances to their nearest codewords. 18. The method of claim 17, wherein the plurality of points in the signal constellation are selected from points in signal constellations for quadrature phase shift keying (QPSK), M-ary phase shift keying (M-PSK), M-ary quadrature amplitude modulation (M-QAM), or a combination thereof. 19. An access terminal in a wireless communication system, comprising: a receiver configured to receive a signal from an access network and determine at least one characteristic of a communication link through which the signal is received; a data processor configured to form a message indicative of a state of the communication link and assign a codeword to the message, the codeword being selected from an alphabet of a plurality of codewords, a minimum distance of the codeword to its nearest codeword in the alphabet being associated with the state of the communication link; and a transmitter unit configured to transmit the message at a particular power level determined based at least in part on the message, wherein the minimum distance of the codeword is based at least in part on how frequently the message is transmitted. 20. An access terminal in a wireless communication system, comprising: a data processor configured to identify a codeword associated with a message, wherein the identified codeword is one of a plurality of codewords defined for an alphabet, and wherein at least two codewords in the alphabet have unequal distances to their nearest codewords, the data processor further configured to determine a transmit power level for the identified codeword, based at least in part on a distance of the identified codeword to its nearest codeword in the alphabet; and a transmitter unit operatively coupled to the data processor and configured to transmit the identified codeword at the determined transmit power level, wherein the plurality of codewords in the alphabet are assigned to the plurality of possible messages such that messages to be transmitted at higher transmit power levels are assigned with codewords having larger distances to their nearest codewords. 21. The access terminal of claim 20, further comprising: a signal quality measurement unit configured to receive samples for a received signal and to determine a received signal quality of signals transmitted from one or more transmitting sources, wherein the transmit power level is associated with the received signal quality of a transmitting source to which the identified codeword is transmitted. 22. A communication unit in a wireless communication system, comprising: a receiver configured to receive a signal from a transmitting source and determine at least one characteristic of a communication link through which the signal is received; a data processor configured to form a message indicative of a state of the communication link and assign a codeword to the message, the assigned codeword being selected from an alphabet of a plurality of codewords, a minimum distance of the assigned codeword to its nearest codeword in the alphabet being associated with the state of the communication link; and a transmitter unit configured to transmit the message at a particular power level determined based at least in part on the message, wherein the minimum distance of the codeword is based at least in part on how frequently the message is transmitted. 23. An apparatus in a wireless communication system, comprising: means for receiving a signal from a transmitting source and determining at least one characteristic of a communication link through which the signal is received; means for forming a message indicative of a state of the communication link; means for assigning a codeword to the message, the assigned codeword being selected from an alphabet of a plurality of codewords, a minimum distance of the assigned codeword to its nearest codeword in the alphabet being associated with the state of the communication link; and means for transmitting the message at a particular transmit power determined based at least in part on the message, wherein the minimum distance of the codeword is based at least in part on how frequently the message is transmitted. 24. The access terminal of claim 19, wherein the power level is determined based at least in part on the minimum distance of the codeword. 25. The access terminal of claim 19, wherein the at least one characteristic comprises a carrier-to-noise-plus interference ratio (C/I). 26. The access terminal of claim 19, wherein the message comprises a data rate control message indicative of a rate for a data transmission requested from the second entity. 27. The access terminal of claim 19, wherein the minimum distance of the codeword is based at least in part on a signal quality of the communication link. 28. The access terminal of claim 20, wherein the plurality of codewords in the alphabet are associated with a plurality of points in a signal constellation, and wherein at least two points in the signal constellation have unequal distances to their nearest codewords. 29. An apparatus in a wireless communication system, comprising: means for identifying a codeword associated with a message, wherein the identified codeword is one of a plurality of codewords defined for an alphabet, and wherein at least two codewords in the alphabet have unequal distances to their nearest codewords; means for determining a transmit power level for the identified codeword, based at least in part on a distance of the identified codeword to its nearest codeword in the alphabet; and means for transmitting the identified codeword at the determined transmit power levels wherein the plurality of codewords in the alphabet are assigned to the plurality of possible messages such that messages to be transmitted at higher transmit power levels are assigned with codewords having larger distances to their nearest codewords.