Briefly explain the three factors which justify the need of modulating low frequency signal into high frequencies.

Explanation

To justify the need for modulating low-frequency signals into high frequencies, we can consider the following three factors:

### Step-by-Step Solution:

1. **Antenna Size Requirement**:
- Low-frequency signals have longer wavelengths. According to the principles of antenna design, the size of the antenna is directly related to the wavelength of the signal it is intended to receive or transmit. Longer wavelengths necessitate larger antennas, which can be impractical for many applications.
- **Conclusion**: Modulating low-frequency signals into high frequencies allows for the use of smaller antennas, making the system more feasible and efficient.

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