BMS 631 - LECTURE 1 Flow Cytometry: Theory J.Paul Robinson Professor of Immunopharmacology School of Veterinary Medicine, Purdue University

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Digital Signal Processing (DSP)

•DSP processors signal continuously at very high rates

•e.g. Take a compact disc which samples at 44.1kHz

•Two conversions are performed (one for each stereo channel) of at least 16 bit resolution are performed every 22.7msec (44.1k/1 second)

•Thus for 16 bit data (2 bytes) at 2 samples per measurement we would have 2 x 44.1 x 2 bytes = 176400 bytes/sec = 10,584,000 bytes/min = 635,040,000 bytes/hour (=620 Mbytes/hour)

•So for really high speed samples we need very high sampling indeed around 20-40 MHz

•This is very costly and is now being achieved at different levels by the manufacturers and essentially removes a huge amount of electronics (pulse width, integration circuits, thresh-holding circuits, comparator circuits, etc)

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