*Question E7F03:
What type of digital signal processing filter is used to generate an SSB signal?*  

*Correct Answer is  C: A Hilbert-transform filter*  

### AI Response: (may contain errors)  

To generate a Single Sideband (SSB) signal, a specific type of digital signal processing filter is required. The correct answer is:

**C: A Hilbert-transform filter**

### Explanation of the Correct Answer:
- **Hilbert-transform filter**: This filter is essential in SSB modulation because it creates a 90-degree phase shift of the input signal. This phase shift allows the generation of the upper or lower sideband of the modulated signal while suppressing the carrier and the unwanted sideband. The Hilbert transform effectively helps in creating an analytic signal, which is crucial for SSB transmission.

### Why the Other Choices are Incorrect:
- **A: An adaptive filter**: 
  - Adaptive filters adjust their parameters based on the input signal characteristics. While they are useful in various applications like noise cancellation, they are not specifically designed for generating SSB signals.

- **B: A notch filter**: 
  - A notch filter is used to eliminate specific frequency components from a signal, typically to remove interference or noise at a particular frequency. It does not create the necessary phase shifts for SSB modulation.

- **D: An elliptical filter**: 
  - Elliptical filters are used for their sharp roll-off characteristics and can be used in various filtering applications. However, they do not provide the specific phase manipulation required for SSB signal generation.

### Summary:
- The Hilbert-transform filter is the key to generating SSB signals due to its ability to create the necessary phase shifts.
- Other filters like adaptive, notch, and elliptical filters serve different purposes and do not fulfill the requirements for SSB modulation.

This understanding is crucial for the Extra Class exam, as it highlights the specific role of the Hilbert-transform filter in SSB signal processing.