Presents the application of such components as MT8980 and MT8924 in digital switch modules for trunking system, and design and implementation of digital switch modules, which can perform the functions of digital switc...Presents the application of such components as MT8980 and MT8924 in digital switch modules for trunking system, and design and implementation of digital switch modules, which can perform the functions of digital switch and conference call, and replace analog switch modules and maintain compatibility with analog systems so that the system can gradually and continuously updated to full digitization.展开更多
1 OverviewTrunking communication is an importantbranch in the mobile communications area.By adopting the PTT(Push-to-Talk)mode,half-duplex single calls and groupcalls can be directly set up.The trunkingtechnology is m...1 OverviewTrunking communication is an importantbranch in the mobile communications area.By adopting the PTT(Push-to-Talk)mode,half-duplex single calls and groupcalls can be directly set up.The trunkingtechnology is mainly employed in the field ofdedicated mobile communications.Like othermobile technologies,the development of trunkingtechnology undergoes a course from analogtechnology to digital technology and then to moreadvanced technologies,and its applied fieldsalso have been changed from dedicatednetworks to common networks.In 2002,ZTE organized its R&D institutes at展开更多
ZTE Corporation has launched its world-leadingGoTa Digital Trunking Communication System inBeijing—a CDMA-based new generation digitaltrunking technology for Chinese and internationalmarkets.It is the first digital t...ZTE Corporation has launched its world-leadingGoTa Digital Trunking Communication System inBeijing—a CDMA-based new generation digitaltrunking technology for Chinese and internationalmarkets.It is the first digital trunking productdeveloped by a Chinese enterprise with anindependent intellectual property right.“This is a product that the global public展开更多
1 GoTa System Features andLocation Service1.1 GoTaGoTa, the abbreviation of“Global OpenTrunking Architecture”, is anew-generation digital trunkingcommunication system based on theCDMA2000 1x technology. It makes use...1 GoTa System Features andLocation Service1.1 GoTaGoTa, the abbreviation of“Global OpenTrunking Architecture”, is anew-generation digital trunkingcommunication system based on theCDMA2000 1x technology. It makes use of manyadvantages of the CDMA technology and makesimprovement and optimization for the digitaltrunking communication system. It cansimultaneously realize multipte services including展开更多
Punch loading is a loading scenario to study the fracture mechanism of materials at low strain rates.In this paper,three punch loading experimental patterns were chosen for the study of compressional punch loading.A p...Punch loading is a loading scenario to study the fracture mechanism of materials at low strain rates.In this paper,three punch loading experimental patterns were chosen for the study of compressional punch loading.A polymer bonded explosive（PBX） simulant was experimentally studied using the digital image correlation（DIC） method.The displacement and strain fields were obtained and the fracture behavior and failure mechanisms of samples were investigated under different punch loading conditions.Moreover,scanning electron microscope（SEM） was used to examine the region of the plastic flow and the damage in the material.The formation of slip bands,shear displacement and fracture of the hard phase particle,were observed on the boundary of the dead zone due to the large shear strains.展开更多
The application of HTSC (high temperature superconductor) microwave devices in a UHF digital trunking communication system is introduced.The replacement between the HTSC microwave devices and the normal microwave devi...The application of HTSC (high temperature superconductor) microwave devices in a UHF digital trunking communication system is introduced.The replacement between the HTSC microwave devices and the normal microwave devices is conducted.The digital sensitivity of the base station in complex electromagnetic environment has been increased to 6 dB,as the results of the experiment indicated,and this means that the coverage radius of the base station has been improved about twice,that is to say,the coverage area can be extended to four times as large as that of the current method.展开更多
无线通信网络对行业用户的安全保卫、突发事件处置、日常业务开展等方面的通信保障起着十分重要的作用,但现有无线通信网络存在通信体制繁杂、集群调度能力弱、安全性低等不足,已无法满足业务发展需求。针对现有无线通信网络痛点,充分...无线通信网络对行业用户的安全保卫、突发事件处置、日常业务开展等方面的通信保障起着十分重要的作用,但现有无线通信网络存在通信体制繁杂、集群调度能力弱、安全性低等不足,已无法满足业务发展需求。针对现有无线通信网络痛点,充分考虑未来发展要求,结合用户安全及使用需求,采用国产警用数字集群(Police Digital Trunking,PDT)通信体制、国密算法和加密标准,为行业用户构建无线通信专网。通过对专网通信体制、安全保密体系架构、技术路线等的研究,对专网进行了总体设计,并提出了实现途径。展开更多
文摘Presents the application of such components as MT8980 and MT8924 in digital switch modules for trunking system, and design and implementation of digital switch modules, which can perform the functions of digital switch and conference call, and replace analog switch modules and maintain compatibility with analog systems so that the system can gradually and continuously updated to full digitization.
文摘1 OverviewTrunking communication is an importantbranch in the mobile communications area.By adopting the PTT(Push-to-Talk)mode,half-duplex single calls and groupcalls can be directly set up.The trunkingtechnology is mainly employed in the field ofdedicated mobile communications.Like othermobile technologies,the development of trunkingtechnology undergoes a course from analogtechnology to digital technology and then to moreadvanced technologies,and its applied fieldsalso have been changed from dedicatednetworks to common networks.In 2002,ZTE organized its R&D institutes at
文摘ZTE Corporation has launched its world-leadingGoTa Digital Trunking Communication System inBeijing—a CDMA-based new generation digitaltrunking technology for Chinese and internationalmarkets.It is the first digital trunking productdeveloped by a Chinese enterprise with anindependent intellectual property right.“This is a product that the global public
文摘1 GoTa System Features andLocation Service1.1 GoTaGoTa, the abbreviation of“Global OpenTrunking Architecture”, is anew-generation digital trunkingcommunication system based on theCDMA2000 1x technology. It makes use of manyadvantages of the CDMA technology and makesimprovement and optimization for the digitaltrunking communication system. It cansimultaneously realize multipte services including
基金Sponsored by the National Natural Science Foundation of China(10832003,11076032)the National Basic Research Program of China(613830202)the Program for New Century Excellent Talents(NCET-06-0159)
文摘Punch loading is a loading scenario to study the fracture mechanism of materials at low strain rates.In this paper,three punch loading experimental patterns were chosen for the study of compressional punch loading.A polymer bonded explosive（PBX） simulant was experimentally studied using the digital image correlation（DIC） method.The displacement and strain fields were obtained and the fracture behavior and failure mechanisms of samples were investigated under different punch loading conditions.Moreover,scanning electron microscope（SEM） was used to examine the region of the plastic flow and the damage in the material.The formation of slip bands,shear displacement and fracture of the hard phase particle,were observed on the boundary of the dead zone due to the large shear strains.
基金supported by the National High-Tech Research and Development Program of China (Grant No. 2007AA03Z212)
文摘The application of HTSC (high temperature superconductor) microwave devices in a UHF digital trunking communication system is introduced.The replacement between the HTSC microwave devices and the normal microwave devices is conducted.The digital sensitivity of the base station in complex electromagnetic environment has been increased to 6 dB,as the results of the experiment indicated,and this means that the coverage radius of the base station has been improved about twice,that is to say,the coverage area can be extended to four times as large as that of the current method.
文摘无线通信网络对行业用户的安全保卫、突发事件处置、日常业务开展等方面的通信保障起着十分重要的作用,但现有无线通信网络存在通信体制繁杂、集群调度能力弱、安全性低等不足,已无法满足业务发展需求。针对现有无线通信网络痛点,充分考虑未来发展要求,结合用户安全及使用需求,采用国产警用数字集群(Police Digital Trunking,PDT)通信体制、国密算法和加密标准,为行业用户构建无线通信专网。通过对专网通信体制、安全保密体系架构、技术路线等的研究,对专网进行了总体设计,并提出了实现途径。
