Bipolar analog signal multiplexing for position-sensitive PET block detectors

Area of Science:

• Instrumentation
• Signal Processing
• Detector Technology

Background:

• Extending axial length or ring radius measurements often requires numerous data acquisition channels.
• High channel counts increase system complexity and cost.

Purpose of the Study:

• To present a novel block detector multiplexing technique to simplify system extension.
• To reduce the number of required data acquisition channels and wire routing density.

Main Methods:

• A bipolar multiplexing circuit encodes detector position signals using polarity combinations.
• Multiple block detectors share a single readout channel for signal discrimination.
• The technique was tested with 1 to 16 block detectors and four data acquisition channels.

Main Results:

• Multiplexing significantly reduced the number of data acquisition channels and wire routing density.
• Timing, energy, and spatial performance remained largely unaffected at low count rates.
• Performance degradation was observed at increased total count rates across all blocks.

Conclusions:

• Bipolar multiplexing offers an effective solution for simplifying detector system scalability.
• The technique is suitable for applications requiring extended measurements with reduced hardware complexity.
• Careful consideration of count rates is necessary to mitigate performance degradation.