A transmitter is the ground-based radio unit that sends control commands to a drone. In FPV and radio-control systems such as ExpressLRS, it converts pilot input into RF packets and broadcasts them to the receiver onboard the aircraft. The transmitter is only one part of the link, but it strongly influences latency, range, and reliability through its power output, packet rate, modulation settings, and antenna quality.
In cyber security and operational safety, the transmitter matters because a control link is only as robust as its weakest component. Poor configuration, interference, or mismatched settings can make a link unstable even when the transmitter is functioning normally. Attackers and defenders both care about this layer: adversaries may try to jam, disrupt, or spoof radio control, while defenders tune transmitter settings and hardware placement to preserve link margin and reduce failures under stress.