Optimum bit rates and power levels are determined for subchannels in multicarrier communication systems. A tangent of the rate-power curve has a slope λ. The slope is defined by the quotient difference between high/low power and high/low rate. A particular λ is evaluated to find its corresponding total power followed by an update of λ, in the form of an increase or decrease, to get closer to the optimal solution. Each λ is evaluated to find the optimal operating point for each subchannel on the rate-power curve by summing the power allocated to the subchannels, and comparing the result to the power budget. Look-up tables are stored for individual channels, but similarity between channels permits joint use of look-up tables by multiple channels. The tables are used to determine the rate-power characteristics at each iteration. An optimal solution is found when either a newly chosen power allocation meets the power budget exactly or a newly chosen power budget equals the high or low power of a previous iteration.
|Original language||English (US)|
|U.S. patent number||6400773|
|State||Published - Jun 4 2002|