Method for measuring the transmission properties of a transmission path of a measurement system based on feedback compensation between a first transmitter and a receiver, for suppressing interferers, in the presence of an interferer, wherein the interferer has a narrow-band signal spectrum, wherein - the first transmitter sends a first signal (I4, I1) into a first transmission path, which first signal is detected by the receiver after passing through at least part of the first transmission path, - a compensation transmitter sends a second signal into a second transmission path, which second signal is detected by the receiver after passing through the second transmission path, - the first signal and the second signal are linearly superimposed in the receiver, and a receiver output signal is formed therefrom, with the following steps: - generating a feed signal by means of a generator, wherein the feed signal and the receiver output signal each form a vector in a pre-Hilbert space and the feed signal is a band-limited feed signal other than zero which has an upper limit frequency ω max and a lower limit frequency ω min, wherein the lower limit frequency ω min is different from the upper limit frequency ω max, wherein the bandwidth of the feed signal is greater than the bandwidth of the signal spectrum of the interferer; - feeding the first transmitter with the feed signal; - performing a forward transformation through a Hilbert projection from the receiver output signal of the receiver to the feed signal by multiplying the receiver output signal by the feed signal, wherein a detection signal is formed first, and by subsequent filtering by means of a filter, wherein a projection image signal is generated from the detection signal; - forming an output signal based on the projection image signal, wherein the output signal comprises information about the transmission properties of the first transmission path; - performing an inverse transformation of the output signal with the feed signal by multiplying the output signal by the feed signal, whereby a pre-signal is formed; - generating a compensation signal from the pre-signal; - feeding the compensation transmitter with the compensation signal for feedback control of the receiver output signal so that an almost constant receiver output signal is produced; characterized in that - the lower limit frequency ω min of the feed signal is greater than half the upper limit frequency ω max of the feed signal, and - the filter is a linear filter which only lets through those frequency components whose frequency magnitude is less than or equal to half the distance between the upper limit frequency ω max and the lower limit frequency ω min of the feed signal. - the first transmitter sends a first signal (I4, I1) into a first transmission path, which first signal is detected by the receiver after passing through at least part of the first transmission path, - a compensation transmitter sends a second signal into a second transmission path, which second signal is detected by the receiver after passing through the second transmission path, - the first signal and the second signal are linearly superimposed in the receiver, and a receiver output signal is formed therefrom, with the following steps: - generating a feed signal by means of a generator, wherein the feed signal and the receiver output signal each form a vector in a pre-Hilbert space and the feed signal is a band-limited feed signal other than zero which has an upper limit frequency ω max and a lower limit frequency ω min, wherein the lower limit frequency ω min is different from the upper limit frequency ω max, wherein the bandwidth of the feed signal is greater than the bandwidth of the signal spectrum of the interferer; - feeding the first transmitter with the feed signal; - performing a forward transformation through a Hilbert projection from the receiver output signal of the receiver to the feed signal by multiplying the receiver output signal by the feed signal, wherein a detection signal is formed first, and by subsequent filtering by means of a filter, wherein a projection image signal is generated from the detection signal; - forming an output signal based on the projection image signal, wherein the output signal comprises information about the transmission properties of the first transmission path; - performing an inverse transformation of the output signal with the feed signal by multiplying the output signal by the feed signal, whereby a pre-signal is formed; - generating a compensation signal from the pre-signal; - feeding the compensation transmitter with the compensation signal for feedback control of the receiver output signal so that an almost constant receiver output signal is produced; characterized in that - the lower limit frequency ω min of the feed signal is greater than half the upper limit frequency ω max of the feed signal, and - the filter is a linear filter which only lets through those frequency components whose frequency magnitude is less than or equal to half the distance between the upper limit frequency ω max and the lower limit frequency ω min of the feed signal.