Abstract: Sensor system resources are consumed as task number increases in multi-task scenario. The system resource requirement is found to be saturated when available resources are used up. Focusing on the multiple emitters tracking scenario with saturated resource requirement, an ESM time-frequency sweeping scheme optimization model is formulated according to the tracking performance preference of different emitters. An optimization algorithm based on period extend and a performance evaluation method with overlapped pie chart is proposed. Simulation results demonstrate that the proposed algorithm achieves better resource efficiency and more reasonable performance assessment.