What happens to the signal bandwidth when the resolution of an image is increased while the sampling rate remains unchanged?

Increasing the resolution of an image while keeping the sampling rate constant will lead to an increase in signal bandwidth. This is because a higher resolution means that there are more pixels per unit area, which results in a more detailed image. Each pixel carries information, so with more pixels and the same sampling rate, the amount of information transmitted increases, thus requiring a broader bandwidth to accommodate this increase.

Bandwidth is fundamentally connected to the amount of data that needs to be processed or transmitted. As the resolution rises, the sheer volume of data that represents the image also grows, necessitating a wider bandwidth to handle the transmission of that data effectively.

In other options, the idea that bandwidth decreases or remains unchanged does not align with the principles of signal processing, where more information (higher resolution) generally requires an increased bandwidth to transmit accurately. Fluctuating bandwidth is also not applicable in this context, as the change in bandwidth due to a shift in image resolution is predictable rather than variable.