A Bird's Eye View: Transmitter Noise

Alfred T. Yerger II, Senior Field Services Engineer, Bird Technologies

For this installment in our series on environmental noise we are going to discuss transmitter noise. Transmitter noise is not always considered part of the environmental noise but it is still very much part of the environment in which our systems have to operate.

All transmitters produce transmitter noise. Transmitter noise is a combination of phase noise from the frequency synthesizer, modulation products and noise from the various amplifier stages that make up the transmitter. Transmitter noise is part of a larger collection of undesired energy produced by a transmitter known as “Out of Band Emissions” (OOBE). We define Out of Band Emissions as any emission on a frequency offset from the assigned channel center by more than 250% of the channel bandwidth.