1. The Clear-PEM Electronics System.
- Author
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Albuquerque, Edgar, Bento, Pedro, Leong, Carlos, Gonçalves, Fernando, Nobre, Joäo, Rego, Joel, Relvas, Paulo, Lousã, Pedro, Rodrigues, Pedro, Teixeira, Isabel C., Teixeira, João P., Silva, Luís, Silva, M. Medeiros, Trindade, Andreia, and Varela, João
- Subjects
POSITRON emission ,POSITRON emission tomography ,MAMMOGRAMS ,SCANNING systems ,MEDICAL imaging systems ,IMAGE processing ,ETHERNET ,FIELD programmable gate arrays ,BREAST cancer - Abstract
The Clear-PEM detector system is a compact positron emission mammography scanner with about 12000 channels aiming at high sensitivity and good spatial resolution. Front-end, Trigger, and Data Acquisition electronics are crucial components of this system. The on-detector front-end is implemented as a data-driven synchronous system that identifies and selects the analog signals whose energy is above a predefined threshold. The off-detector trigger logic uses digitized front-end data streams to compute pulse amplitudes and timing. Based on this information it generates a coincidence trigger signal that is used to initiate the conditioning and transfer of the relevant data to the data acquisition computer. To minimize dead-time, the data acquisition electronics makes extensive use of pipeline processing structures and derandomizer memories with multievent capacity. The system operates at 100-MHz clock frequency, and is capable of sustaining a data acquisition rate of 1 million events per second with an efficiency above 95 %, at a total single photon background rate of 10 MHz. The basic component of the front-end system is a low-noise amplifier-multiplexer chip presently under development. The off-detector system is designed around a dual-bus crate backplane for fast intercommunication between the system boards. The trigger and data acquisition logic is implemented in large FPGAs with 4 million gates. Monte Carlo simulation results evaluating the trigger performance, as well as results of hardware simulations are presented, showing the correctness of the design and the implementation approach. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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