Question

Relation between brightness temperature TB and physical body temperatureTp is ____

(a) TB=\((1-\mid\Gamma_s \mid^2) T_p\)

(b) TB=\(T_p/(1-\mid\Gamma_s \mid^2)\)

(c) TB=\((1-\mid\Gamma_s \mid)T_p\)

(d) TB=\((1-\mid\Gamma_s \mid)^2 T_p\)

I have been asked this question during an internship interview.

Asked question is from Antenna Noise Temperature in portion Antenna Parameters – II of Antennas

Answer 1

The correct option is (a) TB=\((1-\mid\Gamma_s \mid^2) T_p\)

The explanation is: The relation between brightness temperature and the physical body temperature is given by TB=\((1-\mid\Gamma_s \mid^2) T_p\)

Here Γs  is the reflection coefficient for a given polarization and emissivity =\(1-\mid\Gamma_s \mid^2.\)