A Novel Generalized Simulation Technology of Aerospace TT&C Channel

A novel generalized simulation method is proposed to simulate the dynamic transmission delay of wideband and arbitrary signal in aerospace Tracking, telemetry and command (TT&C) channel. This method orthogonally demodulates the wideband and arbitrary Radio-frequency (RF) signal into complex baseband by a Local oscillator (LO) signal. Then the method of dynamic interpolation and delay reconstruction is proposed to obtain the delay reconstruction signal of complex baseband signal based on the variation rules of satellite-to-earth location. Meanwhile, the method of satellite-to-earth distance subsection and polynomial fitting is applied to obtain the delay reconstruction signal of LO signal. The simulated output signal is achieved through the synthesis of two delay reconstruction signals mentioned above. The proposed method can accurately simulate the variation characteristics of time delay and Doppler when wideband and arbitrary RF signal transmits in channel, without knowing any priori knowledge, such as signal form, signal parameters, and so on.