Abstract: The frequency-based method utilizing Effective Vibration Length (EVL) can mitigate boundary effects in short cables, yet existing real-time cable tension identification methods assuming constant EVL may introduce significant errors. This study constructs a complex boundary model of finite element method for short cables and reveals that EVL fluctuates when cable tension varies. To address this, a spline interpolation correction method based on cable tension-EVL data is proposed. Numerical experiments demonstrate that when identifying real-time cable tension using theoretical real-time frequency, the uncorrected relative error ranges from ‒0.98% to ‒9.57%, whereas after correction, the relative error is reduced to ‒2.34%～‒5.08%, with peak errors nearly halved. By comparing four time-frequency analysis methods, it is confirmed that the Synchro-squeezing Transform (SST) offers superior time-frequency resolution. Under the combined application of the EVL correction method and SST, the real-time cable tension identification error at peak and valley positions is reduced from 20% to within 10%. This research validates the effectiveness of integrating dynamic EVL correction with SST time-frequency analysis in enhancing the accuracy of real-time monitoring for short cable tensions.