At the same time , chinasat ' s digital trunking communication has successfully provided telecommunication safeguard for many important conferences such as 10th national games , apec meeting in shanghai , f1 competition , asem finance ministers ' meeting in tianjin , improving the scheduling efficiency greatly and experiencing the fateful trial 同时，中国卫通数字集群通信成功地为第十届全国运动会、上海apec会议、 f1赛事、天津亚欧37国财长会议等重大会议和赛事活动提供了通信保障，极大地提高了指挥调度的工作效率，经受了重大活动对数字集群调度通信的考验。
Abstract : this article gives an overview of technologies of major interest in the radiocommuniction area , such as the wireless access system , the 3g mobile communications system , the two - way paging system , the digital trunked communications system and the bluetooth technology , and the use of frequencies associated with them 摘要：对当前无线通信中的热点问题，如无线接入系统、第三代移动通信系统、双向寻呼移动通信系统、数字集群通信系统以及蓝牙技术等，就它们对频率使用的有关问题进行了综述。
In recent years , digital trunking communication system has come to the sight of people and attracted more attention for its significant advantages , and the tendence that digital trunking communication system will take the place of analogue truking communication system is inevitable in the private mobile communication field 近年来,数字集群通信系统以其特有的优势正在逐步进入人们的视野、引起人们的注意,其取代模拟集群通信系统也已经成为专用通信发展的趋势。
