Microwave sensor system with a variable frequency for the measurement of the tropopause and method for this purpose,

摘要

An apparatus (30) for measuring the properties of the tropopause (26) includes a variable frequency microwave radiometer (40) operating over a range of from about 118.0 to about 119.0 GHz. The radiometer (40) receives as an input a frequency selector signal (52) and produces as an output a measured power level at a measurement frequency corresponding to the input frequency selector signal (52). The apparatus (30) further includes a feedback controller (42) having as an input the measured power level and producing as an output the frequency selector signal (52). The feedback controller (42) varies the frequency selector signal (52) to a target frequency so as to produce a minimum value in the measured power level. The tropopause equivalent altitude is determined from the target frequency.