In telecommunications, particularly in radio, signal strength refers to the magnitude of the electric field at a reference point that is a significant distance from the transmitting antenna. It may also be referred to as received signal level or field strength. Typically, it is expressed in voltage per length or signal power received by a reference antenna. High-powered transmissions, such as those used in broadcasting, are expressed in dB-millivolts per metre (dBmV/m). For very low-power systems, such as mobile phones, signal strength is usually expressed in dB-microvolts per metre (dBµV/m) or in decibels above a reference level of one milliwatt (dBm). In broadcasting terminology, 1 mV/m is 1000 µV/m or 60 dBµ (often written dBu).
- Examples
- 100 dBµ or 100 mV/m: blanketing interference may occur on some receivers
- 60 dBµ or 1.0 mV/m: frequently considered the edge of a radio station's protected area in North America
- 40 dBµ or 0.1 mV/m: the minimum strength at which a station can be received with acceptable quality on most receivers
Read more about Signal Strength: Relationship To Average Radiated Power, Cellphone Signals
Famous quotes containing the words signal and/or strength:
“The experience of a sense of guilt for wrong-doing is necessary for the development of self-control. The guilt feelings will later serve as a warning signal which the child can produce himself when an impulse to repeat the naughty act comes over him. When the child can produce his on warning signals, independent of the actual presence of the adult, he is on the way to developing a conscience.”
—Selma H. Fraiberg (20th century)
“We meet I don’t say when
But must bring to the meeting the maturest,
The longest-saved-up, raciest, localest
We have strength of reserve in us to bring.”
—Robert Frost (1874–1963)