“…The formation of the required frequency-energy characteristics of slot radiators and coupling holes can be ensured, for example, by using combined (with dipoles, dielectric inserts, etc.) radiators [21, 22 and references therein], or by placing in the supply waveguide channel through cavity resonators, which, in turn, are band-pass and band-stop filters [4,16,23]. There are also other constructive solutions to this problem, namely: placement between the radiating slot and the connection slot (slots) the cavity resonator [11,18], and the presence of two closely spaced slots in the wall of the main waveguide makes it possible to significantly increase the value of the coupling coefficient in a narrow frequency band [14].…”