A high resolution phoswich detector has been developed to reduce event mispositioning and improve the spatial resolution of the detector. Crystal identification electronics and algorithm is designed for identifying LYSO and YSO crystals in phoswich detector coupled to PMT. After shaping and filtering,events are sampled at 105 MSPS by an analog to digital converter (ADC) and acquired by FPCA. A crystal identification algorithm based on Auto - Regressive Moving - Average with noise ( ARMAX) model is proposed. Excellent discrimination rate ( >98% ) has been achieved without considering crosstalk between crystals. For LYSO/YSO array,the system achieves a discrimination rate of ( 93.6% ) . Then the 2Dmap of each kind of crystal has also been generated individually which has little overlap.%设计并实现了一种高分辨率复合晶体探测器和电子学,并提出一种系统辨识的算法.复合晶体探测由LYSO( Lu2-xYxSiO5)和YSO(Y2SiO5)两种晶体交错排列而成,目的在于提高晶格的定位能力,改善空间分辨率.由甄别电路完成对PMT(photomultiplier tube)原始信号的处理,使用了高速ADC对信号连续采样,由FPGA完成波形采集,并能够完成实时基线恢复.甄别算法是分析了探测器响应和电子学采集模型之后提出的,是一种系统辨识算法.晶体甄别是基于提取与信号的衰减时间常数相关量来完成的.对LYSO和YSO的单晶体条实验,其甄别率超过98％；并绘制了甄别后两种晶体的二维直方图(2Dmap),有效地减少晶格间交叠,提高了空间分辨率.
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