相控阵天线的阵元失效会造成绝对时延等性能参数的恶化。利用相控阵天线阵列综合和群时延特性的原理，分析了天线阵元随机分布失效和子阵失效情况下，天线绝对时延随之变化的趋势。通过算例仿真可知，在阵元随机失效数学模型下，天线绝对时延受失效阵元分布形式和失效阵元数量因素影响较大， 20%的阵元失效情况下时延偏差最大达到 0.39 ns；在子阵失效数学模型下，靠近阵面中心位置，子阵失效会导致绝对时延出现较大偏差。分析结果及结论可用于实际相控阵天线绝对时延的修正。

The failure of phased array antenna elements, can worsen the antenna performance such as absolute time delay. By use of the synthesis of array antennas and group delay theory，the variety of absolute time delay is analyzed, versus random distribution of elements failure and sub-array failure. By the random distribution numerical model, simulation results show that absolute time delay is affected by distribution and quantity of failure elements, and the deviation of time delay approaches to 0.39 ns on 20% elements failure. By the sub-array numerical model, the larger deviation of time delay will be caused by sub-array failure near the center of antenna array. The analysis results and the conclusion can be utilized to correct absolute time delay of phased array antenna.