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Balancing criteria

back to balancing overview

1. Introduction

This isn't really an MR, but it is being used to document the default balancing criteria for the various backends.

2. Background

Present criteria :: device is regarded as balanced if power is within NN dB of the target.

This psuedo-MR is part of a series of MRs aimed at creating a production Balancing API in Python. For more information regarding this effort, please refer to the BalancingMetaMR.

3. Requirements

This is where we want input from the staff. Do we want different criteria when RFI is present?

In the following scheme, the criterion depends on the backend that is in use. Here are some suggestions, dependent on backend.

Back End normal with RFI
Spectrometer 1.0 dB 1.5 dB
Spigot 1.0 dB 1.5 dB
SpectralProcessor 2.0 dB 2.0 dB
VLBA 1 dB 3 dB
Radar 1 dB 1.5 dB
BCPM 1 dB 2 dB

(no idea as yet what to use for GASP or CGSR2)

(We do not propose to implement RFI rejection for the Spectral Processor because of the inherent difficulties.)

These numbers are not based on any rigorous analysis. The VLBA and BCPM have their own leveling mechanisms. So if their input levels are within 2-3 dB of the ideal, they are just fine. The Spectral Processor has a high dynamic range, so the level is not very critical.

One problem with the dependence on backend is that the Managers for the Prime Focus, IF Rack, and (to be written) Converter Rack do not know what the backend is. They would have to have an additional parameter giving them the dB tolerance criterion.

We could just adopt criteria for the device with the most stringent requirements, i.e., the Spectrometer/Spigot, and adopt them for all devices, thus eliminating the need for knowing the backend.

-- FrankGhigo - 25 May 2006

Topic BalanceCriteria . { Edit | Attach | Ref-By | Printable | Diffs | r1.5 | > | r1.4 | > | r1.3 | More }
Revision r1.5 - 10 Dec 2006 - 18:06 GMT - AmyShelton
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Software.BalanceCriteria moved from Software.ModificationRequest11C506 on 02 Jun 2006 - 15:15 by FrankGhigo - put it back