Effective radiated power

== Related terms ==
According to the [[Institution of Electrical Engineers]] (UK), ERP is often used as a general reference term for radiated power, but strictly speaking should only be used when the antenna is a half-wave dipole,<ref name=barclay>{{cite book  | others=Institution of Electrical Engineers (contributor) | title=Propagation of Radiowaves | publisher=Institution of Engineering and Technology | series=Volume 2 of Electromagnetics and Radar, IET Digital Library|editor-first=Les|editor-last=Barclay | year=2003 | isbn=978-0-85296-102-5 | url=https://books.google.com/books?id=fBoTO48FBD8C&pg=PA14 | access-date=14 September 2020 | pages=13–14|place=London}}</ref> and is used when referring to FM transmission.<ref name=3mtr/>

==={{anchor}}EMRP===
'''Effective monopole radiated power''' ('''EMRP''') may be used in Europe, particularly in relation to [[medium wave]] broadcasting antennas. This is the same as ERP, except that a short vertical antenna (i.e. a short [[monopole antenna|monopole]]) is used as the reference antenna instead of a half-wave [[dipole]].<ref name=barclay/>

==={{anchor}}CMF===
'''Cymomotive force''' ('''CMF''') is an alternative term used for expressing radiation intensity in [[volt]]s, particularly at the lower frequencies.<ref name=barclay/> It is used in [[Australian law|Australian legislation]] regulating AM broadcasting services, which describes it as: "for a transmitter, [it] means the product, expressed in volts, of: (a)  the electric field strength at a given point in space, due to the operation of the transmitter; and (b)  the distance of that point from the transmitter's antenna".<ref>{{cite web | title=Broadcasting Services (Technical Planning) Guidelines 2017 | website=Federal Register of Legislation|publisher=Australian Government | date=28 September 2017 | url=https://www.legislation.gov.au/Details/F2017L01290 | access-date=14 September 2020}} [[File:CC-BY icon.svg|50px]] Text was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0 Attribution 4.0 International  (CC BY 4.0)] licence.</ref>

It relates to [[AM broadcasting]] only, and expresses the field strength in "[[microvolt]]s per metre at a distance of 1 kilometre from the transmitting antenna".<ref name=3mtr>{{cite web | title=3MTR may get a power increase | website=radioinfo | date=24 November 2011 | url=https://www.radioinfo.com.au/news/3mtr-may-get-power-increase | access-date=14 September 2020}}</ref>