This paper presents a high efficiency Doherty power amplifier suitable for TV band applications. A class AB power amplifier is firstly implemented using a commercial GaN HEMT from Cree Incorporation, achieving a high ...This paper presents a high efficiency Doherty power amplifier suitable for TV band applications. A class AB power amplifier is firstly implemented using a commercial GaN HEMT from Cree Incorporation, achieving a high power-added-efficiency of 77.78% and a 40.593 dBm output power with an associated gain of 21.65 dB. The Doherty amplifier has then been designed following the previous class AB scheme for the main amplifier and a class C scheme for the peak one. This amplifier attained a high power-added-efficiency of 81.94%, a 42.77 dBm output power, an associated gain of 21.32 dB, and an operating frequency bandwidth between 550 and 1000 MHz (58.06% fractional bandwidth) which made it suitable for TV band applications.展开更多
高功率电磁脉冲可在电子信息设备电缆上耦合产生浪涌骚扰,瞬态电压抑制器(transient voltage suppressor,TVS)是抑制浪涌骚扰的重要防护器件。现有TVS器件多为Si基材料,受限于材料特性,在响应速度和通流能力上存在不足。因此,选择Si C...高功率电磁脉冲可在电子信息设备电缆上耦合产生浪涌骚扰,瞬态电压抑制器(transient voltage suppressor,TVS)是抑制浪涌骚扰的重要防护器件。现有TVS器件多为Si基材料,受限于材料特性,在响应速度和通流能力上存在不足。因此,选择Si C材料设计新型Si C-TVS器件,新型器件采用NPN结构,通过动态响应仿真确定了基本参数,对器件在高功率电磁脉冲下的热失效进行了仿真研究。采用深度刻蚀槽工艺加工了该批器件,选取结面积和工作电压相近的Si-TVS进行对比测试;测试结果表明:新研制的Si C-TVS器件在快前沿脉冲下的响应速度显著优于Si-TVS;在10/1000μs浪涌脉冲注入下,Si C-TVS的通流能力为Si-TVS的6倍。展开更多
对于广播电视制播工程项目,为确保直播内容安全播出和内容编辑的时效性,与直播相关的系统和内容编辑系统的核心设备需要接入不间断电源(Uninterruptible Power Supply,UPS)供电回路。因此,在供配电系统设计过程中,如何选择合适的UPS电...对于广播电视制播工程项目,为确保直播内容安全播出和内容编辑的时效性,与直播相关的系统和内容编辑系统的核心设备需要接入不间断电源(Uninterruptible Power Supply,UPS)供电回路。因此,在供配电系统设计过程中,如何选择合适的UPS电源设备技术架构成为一个关键问题。主要探讨了广播电视制播工程项目中UPS电源设备的选用,对UPS高频机和UPS工频机进行了比较分析,进而给出了广播电视制播工程中UPS电源设备的选用策略。展开更多
文摘This paper presents a high efficiency Doherty power amplifier suitable for TV band applications. A class AB power amplifier is firstly implemented using a commercial GaN HEMT from Cree Incorporation, achieving a high power-added-efficiency of 77.78% and a 40.593 dBm output power with an associated gain of 21.65 dB. The Doherty amplifier has then been designed following the previous class AB scheme for the main amplifier and a class C scheme for the peak one. This amplifier attained a high power-added-efficiency of 81.94%, a 42.77 dBm output power, an associated gain of 21.32 dB, and an operating frequency bandwidth between 550 and 1000 MHz (58.06% fractional bandwidth) which made it suitable for TV band applications.
文摘对于广播电视制播工程项目,为确保直播内容安全播出和内容编辑的时效性,与直播相关的系统和内容编辑系统的核心设备需要接入不间断电源(Uninterruptible Power Supply,UPS)供电回路。因此,在供配电系统设计过程中,如何选择合适的UPS电源设备技术架构成为一个关键问题。主要探讨了广播电视制播工程项目中UPS电源设备的选用,对UPS高频机和UPS工频机进行了比较分析,进而给出了广播电视制播工程中UPS电源设备的选用策略。
