This Recommendation provides radio-frequency (RF) channel arrangements for fixed wireless systems (FWSs) operating in the 4 GHz frequency range (3 400-4 200 MHz), which may be used for low, mediumand high-capacity systems. The main text presents a homogeneous pattern of 10 MHz slots, with which specific arrangements for channels multiple of the slots can be designed. Annex 1 presents a number of RF arrangements with channel separation of 30, 40 and 80 MHz, designed in this frequency band, according tothe recommended 10 MHz pattern.