本文件适用于甚高频（VHF）数字链路（VDL）模式4地基无线电 在甚高频波段使用高斯滤波的空地通信发射机和接收机 频移键控（GFSK）调制，信道间隔为25kHz，能够调谐到任何25kHz 国际民航组织甚高频数字链路（VDL）标准和 推荐做法[i.5]。制造商应注意，未来地面收发器的调谐范围也可能涵盖任何25 kHz 从108000兆赫到111975兆赫的通道。本文件要求证明无线电设备的结构应确保 有效使用并支持有效使用无线电频谱，以避免有害干扰“[i。 2].除本文件外，其他欧洲标准规定了与基本要求有关的技术要求 根据指令2014/53/EU[i.2]第3条的其他部分以及单一指令的基本要求 欧洲天空互操作性法规552/2004[i.10]及相关实施规则和/或基本要求 根据欧洲广告标准联盟第216/2008号基本法规[i.3]，经第1108/2009号法规修订[i.4]可适用于 本文件范围内的设备。

The present document applies to 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) [i.5].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 present document contains requirements to demonstrate that ". Radio equipment shall be so constructed that it both effectively uses and supports the efficient use of radio spectrum in order to avoid harmful interference" [i.2].In addition to the present document, other ENs that specify technical requirements in respect of essential requirements under other parts of Article 3 of the Directive 2014/53/EU [i.2] as well as essential requirements under the Single European Sky Interoperability Regulation 552/2004 [i.10] and related implementing rules and/or essential requirements under the EASA basic regulation No 216/2008 [i.3] as amended by Regulation No 1108/2009 [i.4] may apply to equipment within the scope of the present document.