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The “Parkes Spectrometer”, v1.0, was built by Peter McMahon for the Parkes Radio Telescope as an evaluation design for a new multi-beam system. It is a dual polarization, power spectrometer with a 1024 channel Polyphase Filter Bank, using the CASPER IBOB hardware platform. A 30kHz readout rate (i.e. 30,000 spectra per second) was targeted, and this necessitated the use of 10Gbit/s Ethernet.


Each spectrometer:

Frequency channels: 1024 (2048 real samples per spectrum)
Signal input: 5MHz - 400MHz or

400MHz - 800MHz or 800MHz - 1.2GHz

-20dBm to -10dBm (-15dBm nominal) 50Ohm SMA

Integration time: Minimum: 5.12us (195kHz spectral dump rate)

Maximum: 655us (1.5kHz spectral dump rate)

Polyphase filter: 2 taps, Hamming window
Output: Test mode: 100Mbit Ethernet. 32-bits per spectral bin.

Observing mode: 10Gbit Ethernet. 8-bits per spectral bin.

Both spectrometers:

Clock input: 800MHz, 0dBm to +4dBm, 50Ohm SMA
1PPS input: 0 to 3V pulse nominal (into 50Ohms)

2V minimum, 5V maximum. Optional.

Power input: 5V, 7A
Mechanical: 1x IBOB and 1x iADC board on a 6U, 8HP plate
Control and monitor: Set up accumulation and corresponding sync period.

Set up IP addresses, ports, MAC addresses, and ARP table.

Set scaling: 18-bits, binary point at 12.

Set output bit selection.

Set ARM (optional).

User Guide

The August 2008 version of the User Guide is available for download.

Sample Processing Code for Gulp Dumps


The latest build of the Parkes spectrometer is available for download.

This download contains the Simulink models, the compiled bitstream (for the LWIP-enabled version), the User Guide, and the sample C code for processing gulp dumps from the Parspec.

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