ČSN ETSI EN 301 842-4 V1.3.1

The present document applies to the following radio equipment types: - Very High Frequency (VHF) Digital Link (VDL) Mode 4 ground-based radio transmitters and receivers for air-ground communications operating in the VHF band, using Gaussian-filtered Frequency Shift Keying (GFSK) Modulation with 25 kHz channel spacing and capable of tuning to any of the 25 kHz channels from 112,000 MHz to 136,975 MHz as defined in ICAO VHF Digital Link (VDL) Standards and Recommended Practices (SARPs) [7]. The present document provides part 4 of the technical specifications. The present document is designed to ensure that equipment certified to it will be compatible with the relevant ICAO VHF Digital Link (VDL) Standards and Recommended Practices (SARPs) [7] and VDL Mode 4 Technical Manual (TM) [1]. Manufacturers should note that in future the tuning range for the ground transceivers may also cover any 25 kHz channel from 108,000 MHz to 111,975 MHz. The scope of the present document is limited to ground stations. The equivalent specification for airborne stations is ETSI EN 302 842 [i.1]. A description of the scope of the VDL Mode 4 system is provided in part 2 of these technical specifications (see ETSI EN 301 842-2 [5], clause 1).