GBPP -- Green Bank-Berkeley Pulsar Processor
The Green Bank-Berkeley Pulsar Processor, GBPP, was originally called
the Coherent Dispersion Removal Processor, or CDRP. In 1994 a half system CDRP-0
was brought to Green Bank; in 1995 a full system CDRP-2 was brought to Green
Bank. In 1996 the designed CDRP-2 system was completed with the addition of an agile
analog stage of electronics. Observing activities with the 85ft telescope were
consolidated with CDRP-2. CDRP-0 was shipped back to Berkeley. CDRP-2 was renamed
GBPP to provide uniformity amongst the various processors completed or under
construction.
- GBPP - Schematic of processor showing major components.
- Table of nominal bandwidth capability as a function of
Dispersion Measure (column density of electrons) and radio frequency.
- Results from 610 MHz observing with 85ft telescope in Green Bank are available
for the Crab and Vela pulsars.
These present the profiles from individual channels along with bandpass spectra and
average profile over all channels; note that the left and right halves of each display
are from orthogonal linear polarizations.
- Tuning data for synthesizer used as LO in Analog Crate.
- DFB - Schematic of Digital Filter Board showing the major
elements one of its eight channels.
Also of interest here is our DFB paper describing the
DFB which is being submitted to PASP.
- DB - Schematic of Dedisperser Board showing major
elements. Also of interest here is our paper describing the VLSI device developed by
Amar Kapadia et al. which provides the computational kernal of this board -- a 1024-point
complex deconvolution of the dispersion effects of the intervening plasma.
- GBPP - documentation for operations in Green Bank. This is
a somewhat uneven, somewhat rambling compilation of notes and tables in straigth ascii
text. Section hierachy goes from top (>>__) to bottom (>>>>) which is useful for
obtaining summary of contents via grep. Introductory material under online software is
a set of end-to-end instructions for use on 140ft. Also the program sched with its
associated files of hardware.tbl, ty.dat, and scan.exp is important to overall
understanding of current use.
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