Fig. 1. Structure and data processing diagram of the time delay measurement system

Fig. 2. Impact of disturbed signals on the measurement results of the phase difference. (a) Frequencies of disturbed signals; (b) amplitudes of disturbed signals

Fig. 3. Stability analysis of the SSE measurement for a 2-km fiber length. (a) Phase difference; (b) corresponding fiber length

Fig. 4. Accuracy analysis of SSE measurement for different lengths of optical fiber. (a) Linearity; (b) measurement deviation

Fig. 5. Analysis of factors influencing the accuracy of SSE measurements. (a)(b) Frequency and amplitude of the calibrated phase signal; (c) sampling rate of the system