Microwave engineering miscellaneous Easy Questions and Answers

Microwave engineering miscellaneous

Consider the following statements regarding a cavity wavemeter in a reaction type of circuit as shown in Fig.
1. The distance d is made either zero or approximately a guide half-wave length, so that an effective short circuit appears at the waveguide wall when the cavity is at resonance.
2. A dip in the load power occurs as the wavemeter is tuned through resonance.
3. The magnitude of the cavity impedance depends only on the distance d.
4. The magnitude of the power dip depends only on the Q of the cavity.

1. 1 alone is correct
1. 2 alone is correct
1. 1 and 3 are correct
1. 2 and 4 are correct

1. Low attenuation coefficient
1. High attenuation coefficient
1. High VSWR
1. Low VSWR

On a resistively terminated high frequency loss-less transmission line fed by a 500 MHz source, the VSWR is found to be equal to 2 and the first voltage minimum is measured at 30 cm from the load end. What is the value of the ‘normalised’ load resistance?

When 10 mW power is incident at port 1 of the directional coupler shown in Fig. the power meter at port 4 reads 10 μW. When the same power is incident at port 2, the meter reads 10 nW. What are the coupling loss and directivity?