High-Power Millimeter Wave Direct Detection by Glow Discharge Detector

Glow discharge detector (GDD) composed of a commercial miniature neon tube is utilized for direct detection of high-power millimeter waves. The detector was exposed directly to 95-GHz high power emitted from a gyrotron and the detector readings were recorded as a function of the incident power. The response of the GDD was examined for 35-dB range. A linear regime was observed followed by a saturation regime. The detection was done without an amplifying stage as done for low power detection. The detector handling of high power without damage was experimentally demonstrated, even when exposed directly to high power. A dependence of the detector rise time on the measured power was observed. This detector can be used in a diagnostic setup of high power devices such as gyrotrons and free electron lasers. Since the cost of such detector is approximately three orders of magnitude less than a commercial W-band crystal detector, an array of detectors can be made for spatial analysis of a high power device output.