DUAL-PERFORMANCE LOW NOISE AMPLIFIER FOR SATELLITE-BASED RADIOFREQUENCY COMMUNICATION

摘要

A low noise amplifier for a device for receiving a radiofrequency signal from a satellite comprises an amplifier maintained in a leaktight cavity of a cryostat, and a cryogenic refrigerator fixed to the exterior of the cryostat. The amplifier is: - maintained in the leaktight cavity secured to a cold finger of the cryogenic refrigerator, made from a good heat-conducting material and passing without direct contact through the wall of the cryostat; - linked to input and output couplers which each pass through the wall of the cryostat; - functional at an ambient temperature, and at least at a cryogenic temperature well below ambient temperature; and the leaktight cavity of the cryostat contains a gas at a pressure of between a pressure close to the pressure outside the cryostat and 0.1 millibars.