| 摘要 |
1,121,638. Remote estimation of atmospheric temperature. SPERRY RAND CORP. Jan. 9, 1967 [Jan. 7, 1966], No. 1082/67. Heading G1N. Temperature is measured by a radiometer with a directional antenna receiving thermally excited radiation from oxygen molecules in the 60, 000 and 119, 000 megacycle bands. The signal is corrected for (i) variation of antenna beam width with frequency, and (ii) the frequency response of the radiometer to give the weighted-meantemperature of the conical volume in the field of the antenna. Radiometer measuring system. Locally generated noise signals (e. g. from an argon lamp 11) are added to the antenna signals and fed to a sampling-switch 5 together signals from a reference-power-source 7, differences-errorsignal is derived from synchronous detector 20 (energized from the sampling-switch-drivesource) to control a servodriven attenuator 12 so that the sum of the "local noise" plus the antenna signal equals the reference signal. The servosystem also drives a potentiometric transducer 24 which is connected together with the reference source to a "subtraction circuit" 25 to provide a signal corresponding to the antenna signal. Frequency corrections. The local-oscillator frequency-control 29 is connected through an A/D converter 30 to an addressable memory" 31, which gives directly the depth-of-penetration on line 37, and controls a transducer 32 to provide a correction for antennabeam -width and radiometer-frequency-response, from stored calibration data. |
