For the purposes of Class A—
“antenna system” means a set of antennas installed on a building or structure and operated by a single telecommunications code system operator in accordance with his licence;
“development ancillary to radio equipment housing” means the construction, installation, alteration or replacement of structures, equipment or means of access which are ancillary to and reasonably required for the purposes of radio equipment housing;
“development in accordance with a licence” means development carried out by an operator in pursuance of a right conferred on that operator under the telecommunications code, and in accordance with any conditions, relating to the application of that code imposed by the terms of his licence;
“land controlled by an operator” means land occupied by the operator in right of a freehold interest or a leasehold interest under a lease granted for a term of not less than 10 years;
“mast” means a radio mast or a radio tower;
“relevant period” means a period which expires—
six months from the commencement of the construction, installation, alteration or replacement of any apparatus or structure permitted by Class A(a) or Class A(c) or from the commencement of the use permitted by Class A(b), as the case may be, or
when the need for such apparatus, structure or use ceases,
whichever occurs first;
“telecommunication apparatus” means any apparatus falling within the definition of that term in paragraph 1 of Schedule 2 to the Telecommunications Act 1984 (“the 1984 Act”)(1) (the telecommunications code), and includes radio equipment housing;
“the telecommunications code” means the code contained in Schedule 2 to the 1984 Act;
“telecommunications code system operator” means a person who has been granted a licence under section 7 of the 1984 Act (power to license systems) which applies the telecommunications code to him in pursuance of section 10 of that Act (the telecommunications code); and
“telecommunication system” has the meaning assigned to that term by section 4(1) of the 1984 Act (meaning of “telecommunication system” and related expressions).