We present a modified direct demodulation (DD) method for the detection of fast variable objects with the Insight-HXMT Galactic plane survey, which is dedicated to hunting for new transients and monitoring known variable sources. The novelty of the improved DD method is the reconstruction of the modified response matrix, in which the variability of a source is properly handled. Monte Carlo (MC) simulation results demonstrate its power for the detection of variable sources with different time scales, resulting in more accurate location and precise flux monitoring. The application of the method to the Insight-HXMT Galactic plane survey data reveals that the type-II bursts can be well detected for the Rapid Burster MXB 1730–335, with an average rate of 2 bursts ${\mathrm{\text{min}}}^{-1}$ in a manner of the well-known relaxation oscillation.

我们提出了一种改进的直接解调（DD）方法，用于通过Insight-HXMT银河系平面测量来检测快速变量对象，该方法专门用于寻找新的瞬变并监视已知的变量源。改进的DD方法的新颖之处在于修改后的响应矩阵的重构，其中可以正确处理源的可变性。蒙特卡洛（MC）仿真结果证明了其在不同时间范围内检测可变源的能力，从而可以实现更精确的位置和精确的通量监控。该方法在Insight-HXMT银河系平面调查数据中的应用表明，Rapid Burster MXB 1730-335可以很好地检测到II型爆发，平均发生率为2次爆发${\mathrm{\text{分}}}^{-\mathrm{1个}}$ 以众所周知的弛豫振荡的方式。