what is narrow band modulation?
narrow-band frequency modulation. [â²narÂ·Å Â¦band â²frÄÂ·kwÉnÂ·sÄ âmÃ¤jÂ·Éâ²lÄÂ·shÉn] (communications) Frequency-modulated broadcasting system used primarily for two-way voice communication, typically having a maximum deviation of 15 kilohertz or less.