  The first generation Low-Level radio frequency(LLRF) control system
independently developed by IMPCAS, the operating frequency is 162.5MHz for
China ADS, which consists of superconducting cavity amplitude stability
control, phase stability control and the cavity resonance frequency control.
The LLRF control system is based on four samples IQ quadrature demodulation
technique consisting an all-digital closed-loop feedback control. This paper
completed the first generation of ADS LLRF control system in the
low-temperature superconducting cavities LLRF stability and performance online
tests. Through testing, to verify the performance of LLRF control system, to
analysis on emerging issues, and in accordance with the experimental data, to
summarize LLRF control system performance to accumulate experience for the
future control of superconducting cavities.
