In telecommunication, reference noise is the magnitude of circuit noise chosen as a reference for measurement.
Many different levels with a number of different weightings are in current use, and care must be taken to ensure that the proper parameters are stated.
Specific ones include: dBa, dBa(F1A), dBa(HA1), dBa0, dBm, dBm(psoph), dBm0, dBrn, dBrnC, dBrnC0, dBrn(f1-f2), dBrn(144-line), dBx.
Famous quotes containing the words reference and/or noise:
“These roses under my window make no reference to former roses or to better ones; they are for what they are; they exist with God to-day. There is no time to them. There is simply the rose; it is perfect in every moment of its existence.”
—Ralph Waldo Emerson (1803–1882)
“You may say a cat uses good grammar. Well, a cat does—but you let a cat get excited once; you let a cat get to pulling fur with another cat on a shed, nights, and you’ll hear grammar that will give you the lockjaw. Ignorant people think it’s the noise which fighting cats make that is so aggravating, but it ain’t so; it’s the sickening grammar they use.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)