PulseNet:

Thirty-two PulseNets are the digitizing front end and signal processors for the all-sky optical search for extraterrestrial intelligence (optical SETI). This experiment is conducted on a new 72-inch spherical telescope in Harvard, Mass. and images 1.8o by 0.2o of sky on 512 pixel pairs. It is a follow-on experiment to our 5+ year targeted search, and employs a similar search methodology. (See www.oseti.org.)

PulseNet is a 250,000 transistor integrated circuit designed at Harvard and Stanford Universities and manufactured on the TSMC 0.25 um process (through the MOSIS service).

Each PulseNet will receive the analog outputs from 16 pair of photodetectors (photomultiplier tube pixels). Each pair of pixels observes the same spot in the sky taken together they image a larger patch of sky. These analog signals are flash digitized at 1 GHz and on-chip hardware looks for coincident, large amplitude pulses in a pair of pixels (the pairing is done to reduce to false alarm rate). When such events are detected, the flash-converted samples from the coincident pair are quickly steered into on-chip memory (512 bits deep). This data is then passed to the outside world, along with the address of the coincident pixels. Additionally, the chip will have an astronomy module that will monitor the single photon count rates from any pixel pair. Thus we can image the sky as well. (Click here for a less technical description.)

Documentation:

Tools:

Testing:

Scripts:

Photos:

Return to my home page.
visits so far: