A frequency model of OCXO for holdover mode of DP-PLL

A frequency model of an OCXO (ovened controlled crystal oscillator) is suggested to implement a holdover algorithm in a DP-PLL (digital processing-phase locked loop) system. This model is presented simply with second order polynomials with respect to temperature and aging of the OCXO. The model parameters are obtained from experimental data by applying the LSM (least squares method). The holdover algorithm is simulated with the identified model using another experimental data.