Data rate adaptation in multiple-in-multiple-out systems

• US 8,149,810 B1
• Filed: 07/14/2003
• Issued: 04/03/2012
• Est. Priority Date: 02/14/2003
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell International Limited (Marvell Technology Group Limited)
• Inventors: Narasimhan, Ravi, Sampath, Hemanth
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): Gonzalez, Amancio
• Application Number:
  US10/620,024
• Time in Patent Office: 3,186 Days
• Field of Search: 370/329, 370/343, 455/452, 455/67.13, 455/452.2, 455/101, 455/115.1
• US Class Current: 370/343
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04

Abstract

A transmit data rate adaptation method in a multiple-in-multiple-out (MIMO) system with a first transceiver and a second transceiver. The first transceiver transmits signals to the second transceiver. The second transceiver analyzes channel quality of the received signals and uses link adaptation to generate a shortlist of transmit modes to send back to the first transceiver. The first transceiver cycles through the shortlist of transmit modes to find an optimum transmit mode.

Claims

1. A system comprising:

a first transceiver operative to transmit signals in accordance with a first transmit mode over a channel; and

a second transceiver operative to receive the signals, the second transceiver including;

a channel quality module operative to determine a channel quality statistic from the signals,

a selection module operative to select N transmit modes from M transmit modes based on the determined channel quality statistic, where M>

N and where N>

1; and

a transmit module operative to transmit a signal indicating the N transmit modes to the first transceiver;

wherein the first transceiver is operative to transmit signals in accordance with a first one of the N transmit modes in response to receiving the signal indicating the N transmit modes from the second transceiver, and transmit signals in accordance with a second one of the N transmit modes in response to an indication that the signal transmitted in the first one of the N transmit modes was not received at the second transceiver, the first one of the N transmit modes being associated with a data rate higher than a data rate associated with the second one of the N transmit modes.

2. The system of claim 1, wherein the signal indicating the N transmit modes comprises the N transmit modes.

3. The system of claim 1, wherein the signal indicating the N transmit modes comprises indices to a table.

4. The system of claim 1, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

5. The system of claim 1, wherein the first transceiver is operative to continue to transmit signals in accordance with the first one of the N transmit modes in response to an indication that the signal transmitted in said first one of the N transmit modes was received at the second transceiver.

6. The system of claim 5, wherein said indication comprises an acknowledgement (ACK) signal sent by the second transmitter.

7. The system of claim 1, wherein the M transmit modes are stored in a look-up table.

8. The system of claim 7, wherein the first transceiver includes an LUT to store the M transmit modes.

9. The system of claim 8, wherein the signal indicating the N transmit modes comprises transmit mode indices corresponding to the N transmit modes.

10. The system of claim 1, wherein the first and second transceivers form a multiple-in multiple-out (MIMO) system.

11. The system of claim 10, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

12. The system of claim 11, wherein the channel quality module is operative to compare the channel quality statistic to the threshold post-processing mean SINRs corresponding to the M transmit modes and select the N transmit modes in response to said comparison.

13. The system of claim 12, wherein the channel quality module statistic comprises an estimated mean SINR.

14. The system of claim 12, wherein the channel quality statistic comprises an outage SINR.

15. The system of claim 11, wherein the M transmit modes are stored in a look-up table.

16. The system of claim 15, wherein the look-up table comprises a set of transmit modes for each of a plurality of spatial multiplexing rates.

17. The system of claim 16, wherein the lookup table with threshold post-processing mean SINRs are based on a generalized reference channel model.

18. The system of claim 17, wherein the generalized reference channel model comprises an orthogonal channel model.

19. The system of claim 17, wherein the generalized reference channel model comprises an Identically Distributed (IID) channel model.

20. The system of claim 1, wherein the first and second transceivers form a single-in single-out (SISO) system.

21. The system of claim 1, wherein the first and second transceivers form a single-in multiple-out (SIMO) system.

22. The system of claim 1, wherein the first and second transceivers form a multiple-in single-out (MISO) system.

23. The system of claim 1, wherein the second transceiver further comprises a transmit module operative to transmit a signal indicating R prohibited transmit modes, where R=M−

N.

24. The system of claim 23, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

25. The system of claim 1, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

26. The system of claim 1, wherein N>

2.

27. A system comprising:

a first transceiver including means for transmitting signals in accordance with a first transmit mode over a channel;

a second transceiver including;

means for receiving the signals,

means for determining a channel quality statistic from the signals,

means for selecting N transmit modes from M transmit modes based on the determined channel quality statistic, where M>

N and where N>

1; and

means for transmitting a signal indicating the N transmit modes to the first transceiver; and

means for transmitting signals in accordance with a first one of the N transmit modes in response to receiving the signal indicating the N transmit modes from the second transceiver, and transmitting signals in accordance with a second one of the N transmit modes in response to an indication that the signal transmitted in the first one of the N transmit modes was not received at the second transceiver, wherein the first one of the N transmit modes is associated with a data rate higher than a data rate associated with the second one of the N transmit modes.

28. The system of claim 27, wherein the signal indicating the N transmit modes comprises the N transmit modes.

29. The system of claim 27, wherein the signal indicating the N transmit modes comprises indices to a table.

30. The system of claim 27, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

31. The system of claim 27, wherein the first transceiver further comprises means for continuing to transmit signals in accordance with the first one of the N transmit modes in response to an indication that the signal transmitted in said first one of the N transmit modes was received at the second transceiver.

32. The system of claim 31, wherein said indication comprises an acknowledgement (ACK) signal sent by the second transmitter.

33. The system of claim 27, wherein the M transmit modes are stored in a look-up table.

34. The system of claim 33, wherein the first transceiver includes an LUT to store the M transmit modes.

35. The system of claim 34, wherein the signal indicating the N transmit modes comprises transmit mode indices corresponding to the N transmit modes.

36. The system of claim 27, wherein the first and second transceivers form a multiple-in multiple-out (MIMO) system.

37. The system of claim 36, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

38. The system of claim 37, wherein the means for determining the channel quality statistic further comprises means for comparing the channel quality statistic to the threshold post-processing mean SINRs corresponding to the M transmit modes and select the N transmit modes in response to said comparison.

39. The system of claim 38, wherein the channel quality module statistic comprises an estimated mean SINR.

40. The system of claim 38, wherein the channel quality statistic comprises an outage SINR.

41. The system of claim 37, wherein the M transmit modes are stored in a look-up table.

42. The system of claim 41, wherein the look-up table comprises a set of transmit modes for each of a plurality of spatial multiplexing rates.

43. The system of claim 42, wherein the lookup table with threshold post-processing mean SINRs are based on a generalized reference channel model.

44. The system of claim 43, wherein the generalized reference channel model comprises an orthogonal channel model.

45. The system of claim 43, wherein the generalized reference channel model comprises an Identically Distributed (IID) channel model.

46. The system of claim 27, wherein the first and second transceivers form a single-in single-out (SISO) system.

47. The system of claim 27, wherein the first and second transceivers form a single-in multiple-out (SIMO) system.

48. The system of claim 27, wherein the first and second transceivers form a multiple-in single-out (MISO) system.

49. The system of claim 27, wherein the second transceiver further comprises means for transmitting a signal indicating R prohibited transmit modes, where R=M−

N.

50. The system of claim 49, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

51. The system of claim 27, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

52. The system of claim 27, wherein N>

2.

53. An apparatus comprising:

a transceiver including;

a transmit module operative to transmit signals in accordance with a first transmit mode over a channel; and

a receive module operative to receive a signal indicating N transmit modes selected from M transmit modes based on a determined channel quality statistic, where M>

N and where N>

1;

the transceiver being operative to transmit signals in accordance with a first one of the N transmit modes in response to receiving the signal indicating the N transmit modes, and transmit signals in accordance with a second one of the N transmit modes in response to an indication that the signal transmitted in the first one of the N transmit modes was not received at a second transceiver, wherein the first one of the N transmit modes is associated with a data rate higher than a data rate associated with the second one of the N transmit modes.

54. The apparatus of claim 53, wherein the signal indicating the N transmit modes comprises the N transmit modes.

55. The apparatus of claim 53, wherein the signal indicating the N transmit modes comprises indices to a table.

56. The apparatus of claim 53, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

57. The apparatus of claim 53, wherein the transceiver is operative to continue to transmit signals in accordance with the first one of the N transmit modes in response to an indication that the signal transmitted in said first one of the N transmit modes was received at a second transceiver.

58. The apparatus of claim 57, wherein said indication comprises an acknowledgement (ACK) signal sent by the second transmitter.

59. The apparatus of claim 53, wherein the M transmit modes are stored in a look-up table.

60. The apparatus of claim 59, wherein the first transceiver include an LUT to store the M transmit modes.

61. The apparatus of claim 60, wherein the signal indicating the N transmit modes comprises transmit mode indices corresponding to the N transmit modes.

62. The apparatus of claim 59, wherein the transceiver forms part of a multiple-in multiple-out (MIMO) system including the transceiver and a second transceiver.

63. The apparatus of claim 62, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

64. The apparatus of claim 59, wherein the look-up table comprises a set of transmit modes for each of a plurality of spatial multiplexing rates.

65. The apparatus of claim 63, wherein the lookup table with threshold post-processing mean SINRs are based on a generalized reference channel model.

66. The apparatus of claim 65, wherein the generalized reference channel model comprises an orthogonal channel model.

67. The apparatus of claim 65, wherein the generalized reference channel model comprises an Identically Distributed (IID) channel model.

68. The apparatus of claim 53, wherein the transceivers forms part of a single-in single-out (SISO) system.

69. The apparatus of claim 53, wherein the transceiver forms part of a single-in multiple-out (SIMO) system.

70. The apparatus of claim 53, wherein the transceiver forms a multiple-in single-out (MISO) system.

71. The apparatus of claim 53, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

72. The apparatus of claim 53, wherein N>

2.

73. An apparatus comprising:

a transceiver including;

means for transmitting signals in accordance with a first transmit mode over a channel,

means for receiving a signal indicating N transmit modes selected from M transmit modes based on a determined channel quality statistic, where M>

N and where N>

1, and

means for transmitting signals in accordance with a first one of the N transmit modes in response to receiving the signal indicating the N transmit modes, and transmitting signals in accordance with a second one of the N transmit modes in response to an indication that the signal transmitted in the first one of the N transmit modes was not received at a second transceiver, the first one of the N transmit modes being associated with a data rate higher than a data rate associated with the second one of the transmit modes.

74. The apparatus of claim 73, wherein the signal indicating the N transmit modes comprises the N transmit modes.

75. The apparatus of claim 73, wherein the signal indicating the N transmit modes comprises indices to a table.

76. The apparatus of claim 73, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

77. The apparatus of claim 73, wherein the transceiver further comprises means for continuing to transmit signals in accordance with the first one of the N transmit modes in response to an indication that the signal transmitted in said first one of the N transmit modes was received at a second transceiver.

78. The apparatus of claim 77, wherein said indication comprises an acknowledgement (ACK) signal sent by the second transmitter.

79. The apparatus of claim 73, wherein the M transmit modes are stored in a look-up table.

80. The apparatus of claim 79, wherein the transceiver includes an LUT to store the M transmit modes.

81. The apparatus of claim 80, wherein the signal indicating the N transmit modes comprises transmit mode indices corresponding to the N transmit modes.

82. The apparatus of claim 79, wherein the transceiver forms part of a multiple-in multiple-out (MIMO) system including the transceiver and a second transceiver.

83. The apparatus of claim 82, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

84. The apparatus of claim 79, wherein the look-up table comprises a set of transmit modes for each of a plurality of spatial multiplexing rates.

85. The apparatus of claim 83, wherein the lookup table with threshold post-processing mean SINRs are based on a generalized reference channel model.

86. The apparatus of claim 85, wherein the generalized reference channel model comprises an orthogonal channel model.

87. The apparatus of claim 85, wherein the generalized reference channel model comprises an Identically Distributed (IID) channel model.

88. The apparatus of claim 73, wherein the transceivers forms part of a single-in single-out (SISO) system.

89. The apparatus of claim 73, wherein the transceiver forms part of a single-in multiple-out (SIMO) system.

90. The apparatus of claim 73, wherein the transceiver forms a multiple-in single-out (MISO) system.

91. The apparatus of claim 73, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

92. The apparatus of claim 73, wherein N>

2.

93. An apparatus comprising:

a transceiver including;

a channel quality module operative to determine a channel quality statistic from one or more received signals,

a selection module operative to select N transmit modes from M transmit modes based on the determined channel quality statistic, where M>

N and where N>

1; and

a transmit module operative to transmit a signal indicating the N transmit modes to a second, different transceiver;

wherein the transceiver is operative to receive signals in accordance with a first one of the N transmit modes from the second transceiver in response to the signal indicating the N transmit modes, and, in response to not receiving the signals in accordance with a first one of the N transmit modes, receiving signals in accordance with a second one of the N transmit modes, the first one of the N transmit modes being associated with a data rate higher than a data rate associated with a second one of the N transmit modes.

94. The apparatus of claim 93, wherein the signal indicating the N transmit modes comprises the N transmit modes.

95. The apparatus of claim 93, wherein the signal indicating the N transmit modes comprises indices to a table.

96. The apparatus of claim 93, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

97. The apparatus of claim 93, wherein the M transmit modes are stored in a look-up table.

98. The apparatus of claim 97, wherein the signal indicating the N transmit modes comprises transmit mode indices corresponding to the N transmit modes.

99. The apparatus of claim 93, wherein the transceiver forms part of a multiple-in multiple-out (MIMO) system.

100. The apparatus of claim 99, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

101. The apparatus of claim 100, wherein the channel quality module is operative to compare the channel quality statistic to the threshold post-processing mean SINRs corresponding to the M transmit modes and select the N transmit modes in response to said comparison.

102. The apparatus of claim 101, wherein the channel quality module statistic comprises an estimated mean SINR.

103. The apparatus of claim 101, wherein the channel quality statistic comprises an outage SINR.

104. The apparatus of claim 100, wherein the M transmit modes are stored in a look-up table.

105. The apparatus of claim 104, wherein the look-up table comprises a set of transmit modes for each of a plurality of spatial multiplexing rates.

106. The apparatus of claim 105, wherein the lookup table with threshold post-processing mean SINRs are based on a generalized reference channel model.

107. The apparatus of claim 106, wherein the generalized reference channel model comprises an orthogonal channel model.

108. The apparatus of claim 106, wherein the generalized reference channel model comprises an Identically Distributed (IID) channel model.

109. The apparatus of claim 93, wherein the transceiver forms part of a single-in single-out (SISO) system.

110. The apparatus of claim 93, wherein the transceiver forms part of a single-in multiple-out (SIMO) system.

111. The apparatus of claim 93, wherein the transceiver forms part of a multiple-in single-out (MISO) system.

112. The apparatus of claim 93, wherein the transceiver further comprises a transmit module operative to transmit a signal indicating R prohibited transmit modes, where R=M−

N.

113. The apparatus of claim 112, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

114. The apparatus of claim 93, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

115. The apparatus of claim 93, wherein N>

2.

116. An apparatus comprising:

a transceiver including;

means for determining a channel quality statistic from one or more received signals,

means for selecting N transmit modes from M transmit modes based on the determined channel quality statistic, where M>

N and where N>

1;

means for transmitting a signal indicating the N transmit modes to a second, different transceiver; and

means for receiving signals in accordance with a first one of the N transmit modes from the second transceiver in response to the signal indicating the N transmit modes, and, in response to not receiving the signals in accordance with a first one of the N transmit modes, receiving signals in accordance with a second one of the N transmit modes, the first one of the N transmit modes being associated with a data rate higher than a data rate associated with a second one of the N transmit modes.

117. The apparatus of claim 116, wherein the signal indicating the N transmit modes comprises the N transmit modes.

118. The apparatus of claim 116, wherein the signal indicating the N transmit modes comprises indices to a table.

119. The apparatus of claim 116, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

120. The apparatus of claim 116, wherein the M transmit modes are stored in a look-up table.

121. The apparatus of claim 120, wherein the signal indicating the N transmit modes comprises transmit mode indices corresponding to the N transmit modes.

122. The apparatus of claim 116, wherein the transceiver forms part of a multiple-in multiple-out (MIMO) system.

123. The apparatus of claim 122, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

124. The apparatus of claim 123, wherein the means for determining the channel quality statistic further comprises means for comparing the channel quality statistic to the threshold post-processing mean SINRs corresponding to the M transmit modes and select the N transmit modes in response to said comparison.

125. The apparatus of claim 124, wherein the channel quality module statistic comprises an estimated mean SINR.

126. The apparatus of claim 124, wherein the channel quality statistic comprises an outage SINR.

127. The apparatus of claim 123, wherein the M transmit modes are stored in a look-up table.

128. The apparatus of claim 127, wherein the look-up table comprises a set of transmit modes for each of a plurality of spatial multiplexing rates.

129. The apparatus of claim 128, wherein the lookup table with threshold post-processing mean SINRs are based on a generalized reference channel model.

130. The apparatus of claim 129, wherein the generalized reference channel model comprises an orthogonal channel model.

131. The apparatus of claim 129, wherein the generalized reference channel model comprises an Identically Distributed (IID) channel model.

132. The apparatus of claim 116, wherein the transceiver forms part of a single-in single-out (SISO) system.

133. The apparatus of claim 116, wherein the transceiver forms part of a single-in multiple-out (SIMO) system.

134. The apparatus of claim 116, wherein the transceiver further comprises means for transmitting a signal indicating R prohibited transmit modes, where R=M−

N.

135. The apparatus of claim 134, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

136. The apparatus of claim 116, wherein the transceiver forms part of a multiple-in single-out (MISO) system.

217. The apparatus of claim 116, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

218. The apparatus of claim 116, wherein N>

2.

137. A method comprising:

transmitting signals from a first transceiver in accordance with a first transmit mode over a channel;

receiving the signals at a second transceiver;

determining a channel quality statistic from the signals;

selecting N transmit modes from M transmit modes based on the determined channel quality statistic, where M>

N and where N>

1;

transmitting a signal indicating the N transmit modes to the first transceiver;

transmitting signals from the first transceiver in accordance with a first one of the N transmit modes in response to receiving the signal indicating the N transmit modes from the second transceiver; and

transmitting signals from the first transceiver in accordance with a second one of the N transmit modes in response to an indication that the signal transmitted in the first one of the N transmit modes was not received at the second transceiver, wherein the first one of the N transmit modes is associated with a data rate higher than a data rate associated with the second one of the N transmit modes.

138. The method of claim 137, wherein the signal indicating the N transmit modes comprises the N transmit modes.

139. The method of claim 137, wherein the signal indicating the N transmit modes comprises indices to a table.

140. The method of claim 137, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

141. The method of claim 137, further comprising continuing to transmit signals from the first transceiver in accordance with the first one of the N transmit modes in response to an indication that the signal transmitted in said first one of the N transmit modes was received at the second transceiver.

142. The method of claim 141, wherein said indication comprises an acknowledgement (ACK) signal sent by the second transmitter.

143. The method of claim 137, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

144. The method of claim 143, wherein said determining the channel quality statistic further comprises comparing the channel quality statistic to the threshold post-processing mean SINRs corresponding to the M transmit modes and select the N transmit modes in response to said comparison.

145. The method of claim 144, wherein the channel quality module statistic comprises an estimated mean SINR.

146. The method of claim 144, wherein the channel quality statistic comprises an outage SINR.

147. The method of claim 137, further comprising transmitting a signal indicating R prohibited transmit modes, where R=M−

N.

148. The method of claim 147, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

149. The method of claim 137, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

150. The method of claim 137, wherein N>

2.

151. A method comprising:

transmitting signals in accordance with a first transmit mode over a channel;

receiving a signal indicating N transmit modes selected from M transmit modes based on a determined channel quality statistic, where M>

N and where N>

1;

transmitting signals in accordance with a first one of the N transmit modes in response to receiving the signal indicating the N transmit modes; and

transmitting signals in accordance with a second one of the N transmit modes in response to an indication that the signal transmitted in the first one of the N transmit modes was not received at a second transceiver, wherein the first one of the N transmit modes is associated with a data rate higher than a data rate associated with the second one of the N transmit modes.

152. The method of claim 151, wherein the signal indicating the N transmit modes comprises the N transmit modes.

153. The method of claim 151, wherein the signal indicating the N transmit modes comprises indices to a table.

154. The method of claim 151, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

155. The method of claim 151, further comprising continuing to transmit signals in accordance with the first one of the N transmit modes in response to an indication that the signal transmitted in said first one of the N transmit modes was received at a second transceiver.

156. The method of claim 155, wherein said indication comprises an acknowledgement (ACK) signal sent by the second transmitter.

157. The method of claim 151, wherein the M transmit modes are stored in a look-up table.

158. The method of claim 151, wherein the signal indicating the N transmit modes comprises transmit mode indices corresponding to the N transmit modes.

159. The method of claim 151, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

160. The method of claim 151, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

161. The method of claim 151, wherein N>

2.

162. A method comprising:

receiving signals transmitted in accordance with a first transmit mode over a channel;

determining a channel quality statistic from the one or more signals received over a channel;

selecting N transmit modes from M transmit modes based on the determined channel quality statistic, where M>

N and where N>

1;

transmitting a signal indicating the N transmit modes to a transceiver that transmitted the received signals;

receiving signals in accordance with a second one of the N transmit modes;

wherein the signals in accordance with the second one of the N transmit modes are transmitted in response to an indication that signals in accordance with the first one of the N transmit modes were not received, and

wherein the first one of the N transmit modes is associated with a data rate higher than a data rate associated with a second one of the N transmit modes.

163. The method of claim 162, wherein the signal indicating the N transmit modes comprises the N transmit modes.

164. The method of claim 162, wherein the signal indicating the N transmit modes comprises indices to a table.

165. The method of claim 162, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

166. The method of claim 162, wherein the signal indicating the N transmit modes comprises transmit mode indices corresponding to the N transmit modes.

167. The method of claim 162, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

168. The method of claim 167, wherein said determining the channel quality statistic further comprises comparing the channel quality statistic to the threshold post-processing mean SINRs corresponding to the M transmit modes and select the N transmit modes in response to said comparison.

169. The method of claim 168, wherein the channel quality module statistic comprises an estimated mean SINR.

170. The method of claim 168, wherein the channel quality statistic comprises an outage SINR.

171. The method of claim 167, wherein the M transmit modes are stored in a look-up table.

172. The method of claim 162, further comprising transmitting a signal indicating R prohibited transmit modes, where R=M−

N.

173. The method of claim 172, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

174. The method of claim 162, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

175. The method of claim 162, wherein N>

2.

176. A non-transitory computer-readable medium having instructions stored thereon, which, when executed by a processor, causes the processor to perform operations comprising:

determining a channel quality statistic from signals transmitted from a first transceiver in accordance with a first transmit mode over a channel and received at a second transceiver;

selecting N transmit modes from M transmit modes based on the determined channel quality statistic, where M>

N and where N>

1;

generating a signal indicating the N transmit modes for transmission to the first transceiver; and

controlling the first transceiver to transmit signals in accordance with a first one of the N transmit modes in response to receiving the signal indicating the N transmit modes from the second transceiver, and transmit signals in accordance with a second one of the N transmit modes in response to an indication that the signal transmitted in the first one of the N transmit modes was not received at the second transceiver, wherein the first one of the N transmit modes is associated with a data rate higher than a data rate associated with the second one of the N transmit modes.

177. The computer-readable medium of claim 176, wherein the signal indicating the N transmit modes comprises the N transmit modes.

178. The computer-readable medium of claim 176, wherein the signal indicating the N transmit modes comprises indices to a table.

179. The computer-readable medium of claim 176, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

180. The computer-readable medium of claim 176, further comprising controlling the first transceiver to continue to transmit signals from the first transceiver in accordance with the first one of the N transmit modes in response to an indication that the signal transmitted in said first one of the N transmit modes was received at the second transceiver.

181. The computer-readable medium of claim 180, wherein said indication comprises an acknowledgement (ACK) signal sent by the second transmitter.

182. The computer-readable medium of claim 176, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

183. The computer-readable medium of claim 182, wherein said determining the channel quality statistic further comprises comparing the channel quality statistic to the threshold post-processing mean SINRs corresponding to the M transmit modes and select the N transmit modes in response to said comparison.

184. The computer-readable medium of claim 183, wherein the channel quality module statistic comprises an estimated mean SINR.

185. The computer-readable medium of claim 183, wherein the channel quality statistic comprises an outage SINR.

186. The computer-readable medium of claim 176, further comprising controlling the first transceiver to transmit a signal indicating R prohibited transmit modes, where R=M−

N.

187. The computer-readable medium of claim 186, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

188. The computer-readable medium of claim 176, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

189. The computer-readable medium of claim 176, wherein N>

2.

190. A non-transitory computer-readable medium having instructions stored thereon, which, when executed by a processor, causes the processor to perform operations comprising:

controlling a first transceiver to transmit signals in accordance with a first transmit mode over a channel;

controlling the first transceiver to transmit signals in accordance with a first one of the N transmit modes in response to a signal indicating the N transmit modes selected from M transmit modes at a second transceiver based on a determined channel quality statistic, where M>

N and where N>

1; and

controlling the first transceiver to transmit signals in accordance with a second one of the N transmit modes in response to an indication that the signal transmitted in the first one of the N transmit modes was not received at a second transceiver, wherein the first one of the N transmit modes is associated with a data rate higher than a data rate associated with the second one of the N transmit modes.

191. The computer-readable medium of claim 190, wherein the signal indicating the N transmit modes comprises the N transmit modes.

192. The computer-readable medium of claim 190, wherein the signal indicating the N transmit modes comprises indices to a table.

193. The computer-readable medium of claim 190, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

194. The computer-readable medium of claim 190, further comprising controlling the first transceiver to continue to transmit signals in accordance with the first one of the N transmit modes in response to an indication that the signal transmitted in said first one of the N transmit modes was received at a second transceiver.

195. The computer-readable medium of claim 194, wherein said indication comprises an acknowledgement (ACK) signal sent by the second transmitter.

196. The computer-readable medium of claim 190, wherein the M transmit modes are stored in a look-up table.

197. The computer-readable medium of claim 190, wherein the signal indicating the N transmit modes comprises transmit mode indices corresponding to the N transmit modes.

198. The computer-readable medium of claim 190, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

199. The computer-readable medium of claim 190, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

200. The computer-readable medium of claim 190, wherein N>

2.

201. A non-transitory computer-readable medium having instructions stored thereon, which, when executed by a processor, causes the processor to perform operations comprising:

determining a channel quality statistic from signals transmitted over a channel;

selecting N transmit modes from M transmit modes based on the determined channel quality statistic, where M>

N and where N>

1; and

controlling a transceiver to transmit a signal indicating the N transmit modes to a second, different transceiver that transmitted signals in accordance with the first transmit mode;

receiving signals in accordance with a first one of the N transmit modes from the second transceiver in response to the signal indicating the N transmit modes, and, in response to not receiving the signals in accordance with a first one of the N transmit modes, receiving signals in accordance with a second one of the N transmit modes, the first one of the N transmit modes being associated with a data rate higher than a data rate associated with a second one of the N transmit modes.

202. The computer-readable medium of claim 201, wherein the signal indicating the N transmit modes comprises the N transmit modes.

203. The computer-readable medium of claim 201, wherein the signal indicating the N transmit modes comprises indices to a table.

204. The computer-readable medium of claim 201, wherein the signal indicating the N transmit modes comprises one or more memory addresses.

205. The computer-readable medium of claim 201, wherein the signal indicating the N transmit modes comprises transmit mode indices corresponding to the N transmit modes.

206. The computer-readable medium of claim 201, wherein each of the M transmit modes has a corresponding threshold post-processing mean signal-to-interference-and-noise ratios (SINRs).

207. The computer-readable medium of claim 206, wherein said determining the channel quality statistic further comprises comparing the channel quality statistic to the threshold post-processing mean SINRs corresponding to the M transmit modes and select the N transmit modes in response to said comparison.

208. The computer-readable medium of claim 207, wherein the channel quality module statistic comprises an estimated mean SINR.

209. The computer-readable medium of claim 207, wherein the channel quality statistic comprises an outage SINR.

210. The computer-readable medium of claim 206, wherein the M transmit modes are stored in a look-up table.

211. The computer-readable medium of claim 201, further comprising controlling a transceiver to transmitting a signal indicating R prohibited transmit modes to the transceiver that transmitted signals in accordance with the first transmit mode, where R=M−

N.

212. The computer-readable medium of claim 211, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

213. The computer-readable medium of claim 201, wherein the signal indicating the N transmit modes is part of an acknowledgment (ACK) or no acknowledgment (NACK) signal.

214. The computer-readable medium of claim 201, wherein N>

2.

215. An apparatus comprising:

a transceiver including;

a transmit module operative to transmit signals in accordance with a first transmit mode over a channel, and

a receive module operative to receive a signal indicating R prohibited transmit modes selected from M transmit modes based on a determined channel quality statistic, where M>

R,

the transceiver being operative to transmit signals to a second, different transceiver in accordance with a first permitted transmit mode other than any of the R prohibited transmit modes in response to receiving the signal indicating the R prohibited transmit modes, and transmit signals in accordance with a second permitted transmit mode other than any of the R prohibited transmit modes in response to an indication that the signal transmitted in accordance with a first permitted transmit mode was not received at the second transceiver, the first permitted transmit mode being associated with a data rate higher than a data rate associated with the second permitted transmit mode.

216. The apparatus of claim 215, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

219. An apparatus comprising:

a transceiver including;

means for transmitting signals in accordance with a first transmit mode over a channel,

means for receiving a signal indicating R prohibited transmit modes selected from M transmit modes based on a determined channel quality statistic, where M>

R, and

means for transmitting signals to a second, different transceiver in accordance with a first permitted transmit mode other than any of the R prohibited transmit modes in response to receiving the signal indicating the R prohibited transmit modes, and transmit signals in accordance with a second permitted transmit mode other than any of the R prohibited transmit modes in response to an indication that the signal transmitted in accordance with a first permitted transmit mode was not received at the second transceiver, the first permitted transmit mode being associated with a data rate higher than a data rate associated with the second permitted transmit mode.

220. The apparatus of claim 219, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

221. A method comprising:

transmitting signals in accordance with a first transmit mode over a channel;

receiving a signal indicating R prohibited transmit modes selected from M transmit modes based on a determined channel quality statistic, where M>

R;

transmitting signals in accordance with a first permitted transmit mode other than any of the R prohibited transmit modes in response to receiving the signal indicating the R prohibited transmit modes; and

transmitting signals in accordance with a second permitted transmit mode other than any of the R prohibited transmit modes in response to an indication that the signal transmitted in accordance with a first permitted transmit mode was not received at the second transceiver, the first permitted transmit mode being associated with a data rate higher than a data rate associated with the second permitted transmit mode.

222. The method of claim 221, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.

223. A non-transitory computer-readable medium having instructions stored thereon, which, when executed by a processor, causes the processor to perform operations comprising:

controlling a first transceiver to transmit signals in accordance with a first transmit mode over a channel;

controlling the first transceiver to transmit signals in accordance with a first permitted transmit mode other than any of R prohibited transmit modes in response to receiving a signal indicating R prohibited transmit modes selected from M transmit modes at a second transceiver based on a determined channel quality statistic, where M>

R; and

controlling the first transceiver to transmit signals in accordance with a second permitted transmit mode other than any of the R prohibited transmit modes in response to an indication that the signal transmitted in accordance with a first permitted transmit mode was not received at the second transceiver, the first permitted transmit mode being associated with a data rate higher than a data rate associated with the second permitted transmit mode.

224. The computer-readable medium of claim 223, wherein the signal indicating the R prohibited transmit modes comprises one of indices to a table, memory addresses, and the R prohibited transmit modes.