Citation
Abstract
The operating noise temperature (T ) of radio frequency (RF) receiving systems op can be calculated using measured power ratios obtained when switching between calibration loads at different temperatures. One method uses the Rayleigh–Jeans (R-J) approximation to determine the noise temperature of the calibration loads [4–6]. An exact calculation uses Planck’s radiation law [4–6]. We show that small receiver (T ) and antenna (T ) noise temperature errors resulting from the use of e i the R-J approximation are self-compensating, and the simpler approximation can be used with an insignificant T error. The accuracy of T , consisting of the op op sum of the calibrated antenna noise temperature and the receiver noise temperature, is adequate using the simplified R-J approximation (physical temperature) at frequencies as high as 100 GHz.
Keywords
Details
- Volume
- 42-154
- Published
- August 15, 2003
- Pages
- 1–7
- File Size
- 125.4 KB