Artificial Pulsar User's Guide
The NRAO in Green Bank has developed a hardware test fixture for validating pulsar data acquisition systems.
This system is called the Artificial Pulsar
. The test fixture has dual polarization outputs.
There are different length cables attaching the signals to the backend inputs, so the relative timing
of signals can not be assumed to be simultaneous.
This note summarizes its functions and typical settings. The artificial pulsar has two major components:
- A commercial signal generation unit that has pulse capability
- A broadband noise source and signal combiner with gain/attenuation capabilities and monitor functions.
Artificial Pulsar hardware, showing the signal generator and gain control,
The signal generator allows a variety of pulse intensities and profiles. The following settings
are commonly used:
- Pulse Frequency: 300 Hz
- Pulse On Output Level: +15 dBm
- Pulse Off Output Level: 0
- Duty Cycle: 1%
- Edge Time: 5.8 nanoseconds
The gain control unit attenuations are:
- Pulsar Attenuation: 22 dB
- Output Attenuation: 3 dB
The gain control unit has an LED readout, with switch selector. With the switch at the "Pulsar" setting, the LED reads 2.75
Output Pulsar Profile
Someone should put a plot here!
- 28 Aug 2008