A method for monitoring a condition of an electrical cable, said method comprising: - applying a broadband signal wave to a first end of the electrical cable, wherein the broadband signal wave is phase and amplitude modulated by at least a cable impedance of the electrical cable, - acquiring at the first end of the cable the phase and amplitude modulated broadband signal wave transmitted and reflected by the electrical cable, - calculating a complex cable impedance Z DUT as a function of frequency f specified by an amplitude and a phase, for the acquired reflected broadband signal wave, - translating the calculated complex cable impedance into a time domain t'; - calculating a frequency f' in the time domain t', wherein the frequency f' is the fundamental frequency of a pseudo-periodic function of radial frequency w' and amplitude A in the time domain t' due to wave reflection of the broadband signal wave at a distance d from an end of the cable, and wherein the frequency f' is calculated by applying: f ' = ω ' 2 π = 2 d v r v 0 in which v 0 is the speed of light in a vacuum and v r, is an estimated relative phase velocity of an electrical signal in the cable; - performing a power spectrum analysis of both amplitude and phase of the complex cable impedance in the time domain t' to find and localize any local degradation to the insulation of the cable; - identifying fre quency components f" 1, f" 2,.... f" n in the power spectrum of the time domain t' due to wave reflections of the broadband signal wave at locations x 1, x 2,...,x n along the cable, the wave reflections being due to discontinuities in electrical parameters of the cable; and calculating each of the locations x i by applying: x i = v r v 0 f i " 2 - establishing a relationship between a real and an imaginary part of a phase impedance spectrum Fourier transform of the power spectrum in an interval around at least one of the locations x 1, x 2,...,x n along the cable, and - identifying impedance changes in at least one of the locations x 1, x 2,...,x n along the cable from said real and imaginary part. - applying a broadband signal wave to a first end of the electrical cable, wherein the broadband signal wave is phase and amplitude modulated by at least a cable impedance of the electrical cable, - acquiring at the first end of the cable the phase and amplitude modulated broadband signal wave transmitted and reflected by the electrical cable, - calculating a complex cable impedance Z DUT as a function of frequency f specified by an amplitude and a phase, for the acquired reflected broadband signal wave, - translating the calculated complex cable impedance into a time domain t'; - calculating a frequency f' in the time domain t', wherein the frequency f' is the fundamental frequency of a pseudo-periodic function of radial frequency w' and amplitude A in the time domain t' due to wave reflection of the broadband signal wave at a distance d from an end of the cable, and wherein the frequency f' is calculated by applying: f ' = ω ' 2 π = 2 d v r v 0 in which v 0 is the speed of light in a vacuum and v r, is an estimated relative phase velocity of an electrical signal in the cable; - performing a power spectrum analysis of both amplitude and phase of the complex cable impedance in the time domain t' to find and localize any local degradation to the insulation of the cable; - identifying fre quency components f" 1, f" 2,.... f" n in the power spectrum of the time domain t' due to wave reflections of the broadband signal wave at locations x 1, x 2,...,x n along the cable, the wave reflections being due to discontinuities in electrical parameters of the cable; and - establishing a relationship between a real and an imaginary part of a phase impedance spectrum Fourier transform of the power spectrum in an interval around at least one of the locations x 1, x 2,...,x n along the cable, and - identifying impedance changes in at least one of the locations x 1, x 2,...,x n along the cable from said real and imaginary part.