A parabolic reflective antenna of 2m diameter operates at a frequency of 129Hz, Determine the; Area of antenna Antenna gain

Area of Antenna

The area of a parabolic antenna is given by:

```
A = π(D/2)^2
```

where:

- A is the area (m²)
- D is the diameter (m)

Plugging in the given values:

```
A = π(2m/2)^2 = 3.14 m²
```

Antenna Gain

The antenna gain of a parabolic antenna is given by:

```
G = (4πA)/(λ²)
```

where:

- G is the antenna gain (dB)
- A is the area (m²)
- λ is the wavelength (m)

The wavelength is related to the frequency by:

```
λ = c/f
```

where:

- c is the speed of light (3 x 10^8 m/s)
- f is the frequency (Hz)

Plugging in the given values:

```
λ = 3 x 10^8 m/s / 129 Hz = 2.326 x 10^6 m
```

Now we can calculate the antenna gain:

```
G = (4π - 3.14 m²) / (2.326 x 10^6 m)² = 0.00044 dB
```

Therefore, the antenna gain is 0.00044 dB.