| 摘要 |
PURPOSE:To decrease the number of switches and to eliminate the need for the sky horn fitting hole of a satellite structure by providing a receiving antenna with the function of a sky horn and the function of a room temperature dummy. CONSTITUTION:The receiving antenna 1 rotates around axes Xa and Xb parallel to the earth 9 continuously in one direction. Therefore, the receiving antenna 1 faces the earth 9 to be measured in one-third (120 deg. visual angle) as long as one turn and antenna temperature TA is measured. Further, the antenna 1 operates as a noise source (low-temperature side) for temperature calibration in the half of the remaining two thirds of one turn to measure antenna temperature T1; and the antenna faces the room temperature dummy calibrated by a temperature sensor provided to the upper part in the remaining half and operates as a noise source (high-temperature side) for temperature calibration to measure antenna temperature T2. This cycle is repeated to perform the reception of a noise radio wave from the object of observation which is required for the microwave radiometer and its temperature calibration. |
