How to make receiver system temperature constant?

[tony_lth]

My customer needs my receiver system temperature constant. My receiver system includes LNA, Pre-filter, Mixer, and isolator. How to keep the receiver system temperature constant?
Someone suggests use some part numbers to heat the components to more than 50 degree, but I have no idea bout that circuits. Who can give suggestions or typical circuits or application notes about the heating systems.
Thanks in advance.

 

[FvM]

I guess, you are aware of temperature controlled crystal oscillators, TXCOs. You can design a similar electronical thermostate for the RF system as a whole. It involves a metal enclosure (you'll already have it with a RF system), heater, temperature sensor and controller. You most easily achieve a homogenous temperature with widespread heater elements at the enclosure's outside, e.g. foil heaters. Wrap thermal insulation around it, e.g. styrofoam.

 

[biff44]

Mount the temperature sensitive components on a metal plate, put that plate on thermal insulating standoffs, and add proportional controlled heater elements. Make sure the heaters are electrically isolated from the metal plate! Also, make sure there is a power supply shutoff/crowbar in case the temperature runs away with the RF components heat!

I would set it at 50 deg C.

 

[chris109]

I agree with FvM stick a foil heater to the metal can protecting the RF components and place a thermister inside the can. Then if you have a spare ADC input, use that to monitor the temp from the thermistor (create a simple thermostat), use MOSFET to switch the heater, switch ON at 48C and off at 52C. If no spare ADC then use a comparator to switch the MOSFET. Also for protection use an inline thermistor switch attached to the inside of the can to protect against over temp.

Or depending on how accurate your temp control needs to be, you can buy panel heaters to just heat the entire control panel (if you have the space), they have built-in thermostat control.

 

[tony_lth]

Thank you very much. I am just curious whether the OCXO have any decreasing-temperarure function?