由于受到模数/数模转换器的转换速率限制,软件无线电还无法完全实现宽带射频信号直接转换。利用射频前端实现宽带射频信号和中频信号之间的转换,是现阶段软件无线电技术发展中的关键技术之一。射频前端的性能直接影响到软件无线电系统...由于受到模数/数模转换器的转换速率限制,软件无线电还无法完全实现宽带射频信号直接转换。利用射频前端实现宽带射频信号和中频信号之间的转换,是现阶段软件无线电技术发展中的关键技术之一。射频前端的性能直接影响到软件无线电系统整体的工作状态。介绍了软件无线电射频前端的发展现状及常用的测试方法,举例说明了方法在超高频(Ultra High Frequency,UHF)无线收发机测试中的应用。展开更多
针对基于光纤无线技术RoF的分布式天线系统架构,设计和实现了一种基于JEDEC的JESD207标准的射频-基带数字并行接口和Xi l i nx的高速串行Rocket IOTM技术、适用于分布式基站系统的射频-基带高速串行接口方案。该方案具有使用灵活、便于...针对基于光纤无线技术RoF的分布式天线系统架构,设计和实现了一种基于JEDEC的JESD207标准的射频-基带数字并行接口和Xi l i nx的高速串行Rocket IOTM技术、适用于分布式基站系统的射频-基带高速串行接口方案。该方案具有使用灵活、便于功能扩展和易于实现等特点,已用于基于RoF的无线通信实验系统。展开更多
A radio frequency （RF） receiver frontend for single-carrier ultra-wideband （SC-UWB） is presented. The front end employs direct-conversion architecture, and consists of a differential low noise amplifier （LNA）, a...A radio frequency （RF） receiver frontend for single-carrier ultra-wideband （SC-UWB） is presented. The front end employs direct-conversion architecture, and consists of a differential low noise amplifier （LNA）, a quadrature mixer, and two intermediate frequency （IF） amplifiers. The proposed LNA employs source inductively degenerated topology. First, the expression of input impedance matching bandwidth in terms of gate-source ca- pacitance, resonant frequency and target Sll is given. Then, a noise figure optimization strategy under gain and power constraints is proposed, with consideration of the integrated gate inductor, the bond-wire inductance, and its variation. The LNA utilizes two stages with different resonant frequencies to acquire flat gain over the 7.1-8.1 GHz frequency band, and has two gain modes to obtain a higher receiver dynamic range. The mixer uses a double bal- anced Gilbert structure. The front end is fabricated in a TSMC 0.18-μm RF CMOS process and occupies an area of 1.43 mm2. In high and low gain modes, the measured maximum conversion gain are 42 dB and 22 dB, input 1 dB compression points are -40 dBm and -20 dBm, and Sll is better than -18 dB and -14.5 dB. The 3 dB IF bandwidth is more than 500 MHz. The double sideband noise figure is 4.7 dB in high gain mode. The total power consumption is 65 mW from a 1.8 V supply.展开更多
文摘由于受到模数/数模转换器的转换速率限制,软件无线电还无法完全实现宽带射频信号直接转换。利用射频前端实现宽带射频信号和中频信号之间的转换,是现阶段软件无线电技术发展中的关键技术之一。射频前端的性能直接影响到软件无线电系统整体的工作状态。介绍了软件无线电射频前端的发展现状及常用的测试方法,举例说明了方法在超高频(Ultra High Frequency,UHF)无线收发机测试中的应用。
文摘针对基于光纤无线技术RoF的分布式天线系统架构,设计和实现了一种基于JEDEC的JESD207标准的射频-基带数字并行接口和Xi l i nx的高速串行Rocket IOTM技术、适用于分布式基站系统的射频-基带高速串行接口方案。该方案具有使用灵活、便于功能扩展和易于实现等特点,已用于基于RoF的无线通信实验系统。
基金Project supported by the National Science and Technology Major Projects of China （Nos. 2011ZX03004-001-02, 2010ZX03007-001-03）.
文摘A radio frequency （RF） receiver frontend for single-carrier ultra-wideband （SC-UWB） is presented. The front end employs direct-conversion architecture, and consists of a differential low noise amplifier （LNA）, a quadrature mixer, and two intermediate frequency （IF） amplifiers. The proposed LNA employs source inductively degenerated topology. First, the expression of input impedance matching bandwidth in terms of gate-source ca- pacitance, resonant frequency and target Sll is given. Then, a noise figure optimization strategy under gain and power constraints is proposed, with consideration of the integrated gate inductor, the bond-wire inductance, and its variation. The LNA utilizes two stages with different resonant frequencies to acquire flat gain over the 7.1-8.1 GHz frequency band, and has two gain modes to obtain a higher receiver dynamic range. The mixer uses a double bal- anced Gilbert structure. The front end is fabricated in a TSMC 0.18-μm RF CMOS process and occupies an area of 1.43 mm2. In high and low gain modes, the measured maximum conversion gain are 42 dB and 22 dB, input 1 dB compression points are -40 dBm and -20 dBm, and Sll is better than -18 dB and -14.5 dB. The 3 dB IF bandwidth is more than 500 MHz. The double sideband noise figure is 4.7 dB in high gain mode. The total power consumption is 65 mW from a 1.8 V supply.
