Which of the following modulated signal has the best noise-tolerance ?

Options

A. long-wave
B. short-wave
C. medium-wave
D. amplitude-modulated

Answer

To determine which modulated signal has the best noise tolerance, we need to analyze the characteristics of different types of waves and their susceptibility to noise. Here’s a step-by-step solution:

### Step 1: Understand Noise
- **Definition**: Noise refers to unwanted signals that interfere with the transmission of desired signals between a transmitter and a receiver.
- **Impact**: Noise can distort the original signal, making it difficult for the receiver to accurately interpret the transmitted information.

### Step 2: Define Noise Tolerance
- **Noise Tolerance**: This refers to the ability of a signal to withstand interference from noise without significant degradation in quality. A signal with high noise tolerance can maintain its integrity despite the presence of noise.

### Step 3: Analyze Different Wave Types
- **Long Wave**: These waves have longer wavelengths and are generally more susceptible to noise.
- **Medium Wave**: These waves have moderate wavelengths and show moderate noise tolerance.
- **Short Wave**: These waves have shorter wavelengths and are known to have the best noise tolerance among the three types.

### Step 4: Order of Noise Tolerance
- Based on the analysis:
1. **Short Wave** - Best noise tolerance
2. **Medium Wave** - Moderate noise tolerance
3. **Long Wave** - Least noise tolerance

### Step 5: Conclusion
- From the analysis, we conclude that the modulated signal with the best noise tolerance is the **Short Wave**.

### Final Answer
- **Short Wave** has the best noise tolerance.

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