A low bandwidth signal does not have more power.

Signal Bandwidth is the Bandwidth of particular frequency at which signal is transmitted and Bandwidth of spectrum which can able two show number of signal between Intrest of frequency.

facsimile signal requires a bandwidth of only about 1000 Hz

In signal processing, baseband describes signals and systems whose range of frequencies is measured from zero to a maximum bandwidth or highest signal frequency; it is sometimes used as a noun for a band of frequencies starting at zero.

Bandwidth can be interpreted several different ways. Most commonly it's the rate data is transferred. However, it's originally from signal processing and it was to measure frequencies measured in hertz.