Line of sight (LOS) communication is also known as

Options

A. Ground wave communication
B. Space wave communication
C. Sky wave communication
D. ionospheric communication

Answer

### Step-by-Step Solution:

1. **Understanding Line of Sight (LOS) Communication**:
- Line of sight communication refers to a method of transmitting signals where the transmitter and receiver are directly visible to each other. This means that the signal travels in a straight line without any obstacles in between.

2. **Frequency Characteristics**:
- In line of sight communication, the frequencies used are typically greater than 40 megahertz. This high frequency is essential for effective transmission over distances and helps in minimizing the effects of obstacles.

3. **Relation to Space Wave Communication**:
- Line of sight communication is closely related to space wave communication. Both utilize high frequencies (greater than 40 MHz) to ensure that signals can penetrate the atmosphere and reach their destination effectively.

4. **Conclusion**:
- Given the characteristics of line of sight communication and its association with high-frequency transmission, it is also referred to as space wave communication.

### Final Answer:
Line of sight (LOS) communication is also known as **space wave communication**.

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