Baseline recovery techniques for photon counting computed tomography using active references

One embodiment is a circuit for implementing a baseline recovery ("BLR") circuit for a photon counting computed tomography ("PCCT") signal chain, the circuit comprising: a multi-level discriminator circuit for receiving a shaper voltage from the PCCT signal chain, the discriminator circuit outputting a digital signal indicative of one of the voltage ranges in which the shaper voltage falls; a digital-to-analog converter ("DAC") connected to receive the digital signal output from the discriminator circuit, the DAC converting the received digital signal into a corresponding active reference voltage; and a feedback circuit injecting a cancellation current proportional to a difference between the shaper voltage and the active reference voltage at a specific node of the PCCT signal chain. 一个实施例是一种用于实现光子计数计算机断层扫描("PCCT")信号链的基线恢复("BLR")电路的电路，所述电路包括：多电平鉴别器电路，用于从所述PCCT信号链接收整形器电压,所述鉴别器电路输出指示所述整形器电压落在其中的电压范围之一的数字信号；数模转换器("DAC")，连接以接收从鉴别器电路输出的数字信号,DAC将接收的数字信号转换为相应的有源参考电压；和反馈电路，在所述PCCT信号链的特定节点处注入与所述整形器电压与所述有源参考电压之间的差成比例的抵