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针对地空频率域电磁法 (GAFEM) 的大范围、快速探测需求, 研制了一种适用于GAFEM的高灵敏度、低噪声、低质量的空心线圈传感器 (ACS) .首先, 根据一维正演计算了收发距10 km处的等效面积归一化响应电压, 进而确定传感器灵敏度和噪声水平的指标需求;然后, 建立ACS的电路等效模型, 并对电路噪声进行分析计算, 引进拉格朗日乘子法来优化ACS的设计参数以达到灵敏度、噪声和质量指标要求;最后, 根据优化参数设计空心线圈传感器, 在电磁屏蔽室对其进行测试, 结果显示在噪声参考频率 (100 Hz) 处, 优化传感器噪声为0.09 pT/Hz1/2, 灵敏度为14.7 mV/nT, 总质量为1.25 kg.野外实验表明, 地面同一测点处, 本文优化ACS测量的磁场幅度与AMTC-30磁棒的测量值一致;且在空中飞行中, 该ACS能获得有效磁场信号.“,”To meet the requirements of big survey area and rapid exploration of ground-airborne frequency-domain electromagnetic method, an air-core sensor (ACS) is developed for GAFEM with high sensitivity, low noise and low weight. First, based on the one-dimension forward method, the equivalent area normalized response voltage at 10 km is calculated. And the index requirements for ACS′s sensitivity and noise levels are determined. Then, the circuit model of the sensor is built, and the noise of the air-core sensor is analyzed. Low noise and low weight are achieved by optimizing the design parameters of the sensor through lagrangian multiplier method. Finally, according to the optimized parameters, the air-core coil sensor is designed and fabricated, and the sensor is tested in the electromagnetic shielding room. Results show that the noise of coil at noise reference point (100 Hz) reaches 0.09 pT/Hz1/2, the sensitivity is 14.7 mV/nT, and the total weight is 1.25 kg. In addition, field experiments show that the optimized ACS obtained the magnetic which is consistent with that of the AMTC-30 at the same measuring point, and the ACS can acquire effective magnetic data in the practical survey.