Method for reducing interferences between a first carrier current signal transmitted between modems of a power grid and a second signal transmitted between modems of another grid

Device for reducing interference between a first signal of the carrier current type (Se) transmitted between modems (MCPLE) in an electrical network (Re) and a second signal (S) transmitted between modems (M) in another network (R), the said signals (Se, S) being coded by distribution of the data on allocated carrier frequencies of the same reserved frequency band, the said device comprising

• means (MM) so that each modem (MCPL) in the electrical network measures transmission characteristics of each carrier frequency (F) allocated for coding the first signal (Se) or that may be so allocated, and
• means (MO) for optimising the distribution of the data of the first signal (Se) over carrier frequencies so as to minimise the transmission power level of carrier frequencies subject to the constraint of a transmission rate of the first signal (Se), characterised in that it also comprises
• means (MD) for detecting, by analysing the measured transmission characteristics, at least one carrier frequency (F2,n), referred to as the second carrier frequency, which is allocated or may be allocated for coding the second signal (S) and is common with at least one carrier frequency (F1,m), referred to as the first carrier frequency, which is allocated for coding the first signal (Se) and the measured transmission characteristics of which are degraded with respect to the those of a previous measurement, and in that
• the means (MO) for optimising the distribution of the data of the first signal (Se) subject to the constraint of a transmission rate of the first signal (Se) are provided for minimising the transmission power level of the first carrier frequencies (F1,m) that are common with the second carrier frequencies (F2,n) thus detected.

Modem, referred to as the master modem, provided for managing the distribution of carrier frequencies, referred to as first carrier frequencies, of a first signal of the carrier current type (Se) transmitted over an electrical network, the said modem comprising

• means (MR) for receiving transmission characteristics of each carrier frequency that may used measured by each other modem in the electrical network, and
• means (MO) for optimising the distribution of the data of the first signal (Se) over carrier frequencies so as to minimise the transmission power level of carrier frequencies subject to the constraint of a transmission rate of the first signal (Se), characterised in that it also comprises
• means (MD) for detecting, by analysing the said measured transmission characteristics, at least one carrier frequency (F2,n), referred to as the second carrier frequency, which is allocated or may be allocated for coding a second signal (S) transmitted between modems in another network, and is common with at least one carrier frequency (F1,m), referred to as the first carrier frequency, which is allocated for coding the first signal (Se) and the measured transmission characteristics of which are degraded with respect to the those of a previous measurement, and in that
• the means (MO) for optimising the distribution of the data of the first signal (Se) subject to the constraint of a transmission rate of the first signal (Se) are provided for minimising the transmission power level of the first carrier frequencies (F1,m) that are common with the second carrier frequencies (F2,n) thus detected.