Control de amplitud en un entorno de carga variable

摘要

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for varying symbol amplitude. In one aspect, a system includes a symbol generator that includes a waveform generator configured to output waveforms at a plurality of selectable fundamental frequencies and with a selectable duty cycle. The symbol generator can also include a bandpass filter having a pass-band that corresponds to a communications channel of a communications network. The system can also include data processing apparatus operable to interact with the symbol generator and further operable to determine that at least a threshold number of endpoints that receive symbols from the symbol generator are experiencing a same type of transmission error. In response to the determination, the data processing apparatus can cause the waveform generator to adjust at least one of the fundamental frequency or a duty cycle of the waveforms. The fundamental frequency can be adjusted to a frequency having a harmonic that is within the pass-band.