In your catalogue there are antennas with a frequency range that is larger than the bandwidth. Why is this?
The operating frequency is the frequency range in which an antenna is adjusted to allow it to work within its parameters.
Once adjusted, the antenna will perform within both its frequency band and bandwidth.
For example antenna ref. 6571:
This means that the antenna can be adjusted to a frequency between 142 and 235 MHz.
Once it is adjusted, the emission and reception will be within its 5 MHz bandwidth.
So if the antenna is adjusted to work at 156 MHz, it will operate at its optimum level in a frequency band between 153.5 and 158.5 MHz.