世界各国的电台和生产厂家正在促进数字声音广播(DAB)的发展。DAB可以播放小型唱片(DC)和数字小型盒带(DCC)的数字声音。目前,正在进行现场试验,以便于研究人员搜集制定频率规划的资料。根据这些数据,研究人员就可以制定出发射机功率和发射机位置密度的最佳标准。 既使在接收条件较差的情况下,数字声音广播也能给出CD质量的音质。为了克服因多径传播和其它物理条件引起的无线电信号失真,数字声音广播采用编码正交频分多工(COFDM)传输系统。 此外,数字声音广播的另一个优点是没有信号衰落。选择电台时,用户只要向收音机输入所需节 Radio and manufacturers around the world are promoting the development of digital sound broadcasting (DAB). DAB can play digital sounds on compact discs (DCs) and digital compact cassettes (DCCs). At present, field trials are under way to facilitate the researchers in collecting information on the development of frequency planning. Based on these data, researchers can work out the best standards for transmitter power and transmitter position density. Even in poor reception conditions, digital sound broadcasting gives CD quality sound quality. To overcome radio signal distortion caused by multipath propagation and other physical conditions, digital sound broadcasting employs a Coded Orthogonal Frequency Division Multiplexing (COFDM) transmission system. In addition, another advantage of digital sound broadcasting is that there is no signal fading. When selecting a station, the user simply enters the desired section into the radio