Calibrated Thermal Targets PDF Print E-mail

Calibrated Hot Loads

Under contract to ESTEC and with partners AEA Technology PLC, Thomas Keating has developed a Calibrated Hot Load (CHL) for the 400 to 1100 GHz region. This will provide the temperature reference in future space missions requiring accurate radiometric calibration.

The CHL is a scaleless design based upon a tapered cone lined with microwave absorber. It is being Vibrational and thermal vacuum cycled to generate a fully space qualified design. The CHL has outstanding radiometric performance - in particular its monostatic reflectivity is very low at -70dB.

To the left you see a side view of the cone, with power and PRT sensor cable clearly visible. On the right, the cone itself.

 

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and here is a side view.

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Axel Murk has also measured the monostatic performance of the CHL at 400 GHz

JPL Calibration Load

We also machine load to other people's designs: Here is a THz design, machined for the Jet Propulsion Laboratory in Pasadena. Concentric grooves, coated with black paint absorber, provide the absorbing surface. Temperature is measured from sensors potted into the back.

and a view from the back

Technical operation of our CHL

Our colleague Nigel Keen has written a technical note on the CHL:

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