Reradiation

In telecommunication, the term reradiation has the following meanings:

1. Electromagnetic radiation, at the same or different wavelengths, i.e., frequencies, of energy received from an incident wave.
2. Undesirable radiation of signals locally generated in a radio receiver. This type of radiation might cause interference or reveal the location of the device.

Near-field effects of an AM antenna may extend out two miles (3 km) or more. Cellular and microwave towers within this radius can reflect the AM signal out at a different frequency. This process results in interfering frequencies called reradiation.  This article incorporates public domain material from the General Services Administration document "Federal Standard 1037C" (in support of MIL-STD-188).