METHOD AND SYSTEM ALLOWING THE DYNAMIC ALLOCATION OF POWER AND/OR OF MODULATION IN A SYSTEM COMPRISING N CHANNELS

摘要

A method and system is provided for dynamic allocation of power required on a number n with n greater than 1 of an HF communication system, comprising an amplifier of maximum total power and at least one step in which the power and/or the modulation is managed on all the n pathways of said system so as to optimize a given probability of error termed the operating point for a maximum bitrate under the constraint of the total power imposed by the operation of said system.

主权项

1. A method of dynamic allocation of power required for each channel of an HF communication system comprising a number n of channels for signal transmission, the system comprising an amplifier of maximum total power Ptot, and comprising:
a step of initializing the system in which m modulation schemes are defined, and the value SNR of the minimum signal-to-noise ratio which makes it possible to guarantee the target error probability is established for each of the m coding schemes considered and for a channel model considered, a step where a value of power Pnec required in order to attain the value SNR is determined as a function of a value of channel or pathway quality Qch obtained by return pathway, a step of classifying the various channels chn by decreasing level of Qch, generating a vector of n values ordered in a decreasing manner, so that for a given modulation m the power required Pmj in order to transmit on channel j is less than or equal to Pmj+1, where j varies from 1 to at the maximum n channels and eliminate the channels comprising unauthorized frequencies for transmission or having a value of quality lying beyond a level deemed unacceptable a step where for each channel n, by using the value of Qch and the operating value of SNR, a power matrix P=[Pij]i=1 . . . m, j=1 . . . n is deduced, satisfying Pij<=Pij+1 for all j=1 . . . n−1, i:1 . . . m, a row of the matrix corresponds to the transmission of the bitrate di with by construction the relation di>di+1 i=1 . . . m−1, where i varies from 1 to m modulations and j varies from 1 to n channels, for an identical modulation scheme used for all the n channels, a step of determining the number of channels to be used, by considering the matrix P row by row, by computing the power Pi(k)=Σj=1 . . . kPij and the value of the bitrate for a set of k channels, di(k)=kxdi for k from 1 to n, k is the channel index, di=bitrate for the ith modulation, and the selection of a combination of the n channels offering a maximum total bitrate Dtotmax while complying with the total power constraint.