CDMA 2000第三层协议标准 Upper Layer (Layer 3) Signaling Standard for cdma2000 Standards for Spread Spectrum Systems
标签: Layer 2000 Signaling Standards
上传时间: 2015-05-12
上传用户:tuilp1a
Program-controlled switching technology, introduced on the 7th and Signaling technology exchange program
标签: technology Program-controlled introduced switching
上传时间: 2014-01-14
上传用户:ruixue198909
In 揚erformance of multi-carrier DS CDMA Systems?we apply a multi-carrier Signaling technique to a direct-sequence CDMA system, where a data sequence multiplied by a spreading sequence modulates multiple carriers, rather than a single carrier. The receiver provides a correlator for each carrier, and the outputs of the correlators are combined with a maximal-ratio combiner. This type of Signaling has the desirable properties of exhibiting a narrowband interference suppression effect, along with robustness to fading, without requiring the use of either an explicit RAKE structure or an interference suppression filter.
标签: multi-carrier erformance Signaling technique
上传时间: 2017-07-31
上传用户:宋桃子
DSSS Signaling for Range Estimation
标签: Estimation Signaling Range DSSS
上传时间: 2017-08-11
上传用户:缥缈
数字射频存储器(Digital Radio FreqlJencyr:Memory DRFM)具有对射频信号和微波信号的存储、处理及传输能力,已成为现代雷达系统的重要部件。现代雷达普遍采用了诸如脉冲压缩、相位编码等更为复杂的信号处理技术,DRFM由于具有处理这些相干波形的能力,被越来越广泛地应用于电子对抗领域作为射频频率源。目前,国内外对DRFM技术的研究还处于起步阶段,DRFM部件在采样率、采样精度及存储容量等方面,还不能满足现代雷达信号处理的要求。 本文介绍了DRFM的量化类型、基本组成及其工作原理,在现有的研究基础上提出了一种便于工程实现的设计方法,给出了基于现场可编程门阵列(Field Programmable Gate Array FPGA)实现的幅度量化DRFM设计方案。本方案的采样率为1 GHz、采样精度12位,具体实现是采用4个采样率为250 MHz的ADC并行交替等效时间采样以达到1 GHz的采样率。单通道内采用数字正交采样技术进行相干检波,用于保存信号复包络的所有信息。利用FPGA器件实现DRFM的控制器和多路采样数据缓冲器,采用硬件描述语言(Very High Speed}lardware Description Language VHDL)实现了DRFM电路的FPGA设计和功能仿真、时序分析。方案中采用了大量的低压差分信号(Low Voltage Differential Signaling LVDS)逻辑的芯片,从而大大降低了系统的功耗,提高了系统工作的可靠性。本文最后对采用的数字信号处理算法进行了仿真,仿真结果证明了设计方案的可行性。 本文提出的基于FPGA的多通道DRFM系统与基于专用FIFO存储器的DRFM相比,具有更高的性能指标和优越性。
上传时间: 2013-06-01
上传用户:lanwei
The MAX3243E device consists of three line drivers, five line receivers, and a dual charge-pump circuit with±15-kV ESD (HBM and IEC61000-4-2, Air-Gap Discharge) and ±8-kV ESD (IEC61000-4-2, Contact Discharge)protection on serial-port connection pins. The device meets the requirements of TIA/EIA-232-F and provides theelectrical interface between an asynchronous communication controller and the serial-port connector. Thiscombination of drivers and receivers matches that needed for the typical serial port used in an IBM PC/AT, orcompatible. The charge pump and four small external capacitors allow operation from a single 3-V to 5.5-Vsupply. In addition, the device includes an always-active noninverting output (ROUT2B), which allowsapplications using the ring indicator to transmit data while the device is powered down. The device operates atdata Signaling rates up to 250 kbit/s and a maximum of 30-V/ms driver output slew rate.
标签: MULTICHANNEL 5.5 TO RS
上传时间: 2013-10-19
上传用户:ddddddd
A Computer-On-Module, or COM, is a Module with all components necessary for a bootable host computer, packaged as a super component. A COM requires a Carrier Board to bring out I/O and to power up. COMs are used to build single board computer solutions and offer OEMs fast time-to-market with reduced development cost. Like integrated circuits, they provide OEMs with significant freedom in meeting form-fit-function requirements. For all these reasons the COM methodology has gained much popularity with OEMs in the embedded industry. COM Express® is an open industry standard for Computer-On-Modules. It is designed to be future proof and to provide a smooth transition path from legacy parallel interfaces to LVDS (Low Voltage Differential Signaling) interfaces. These include the PCI bus and parallel ATA on the one hand and PCI Express and Serial ATA on the other hand.
上传时间: 2013-11-05
上传用户:Wwill
The Cyclone® III PCI development board provides a hardware platform for developing and prototyping low-power, high-performance, logic-intensive PCI-based designs. The board provides a high-density of the memory to facilitate the design and development of FPGA designs which need huge memory storage, and also includes Low-Voltage Differential Signaling (LVDS) interface of the High-Speed Terasic Connectors (HSTCs) for extra high-speed interface application.
标签: development developing prototypi provides
上传时间: 2017-01-29
上传用户:jjj0202
High volume USB 2.0 devices will be designed using ASIC technology with embedded USB 2.0 support. For full-speed USB devices the operating frequency was low enough to allow data recovery to be handled in a vendors VHDL code, with the ASIC vendor providing only a simple level translator to meet the USB Signaling requirements. Today s gate arrays operate comfortably between 30 and 60 MHz. With USB 2.0 Signaling running at hundreds of MHz, the existing design methodology must change.
标签: technology 2.0 USB designed
上传时间: 2014-01-02
上传用户:二驱蚊器
High volume USB 2.0 devices will be designed using ASIC technology with embedded USB 2.0 support. For full-speed USB devices the operating frequency was low enough to allow data recovery to be handled in a vendors VHDL code, with the ASIC vendor providing only a simple level translator to meet the USB Signaling requirements. Today s gate arrays operate comfortably between 30 and 60 MHz. With USB 2.0 Signaling running at hundreds of MHz, the existing design methodology must change.
标签: technology 2.0 USB designed
上传时间: 2017-07-05
上传用户:zhoujunzhen