用matlab仿真实现了25 kHz 带宽内同时传送总共48 kbit/s 的两路语音(每路速率9. 6 kbit/s) 和两路数据信息(速率分别为19. 2 kbit/s 和9. 6 kbit/s) , 仿真结果表明达到了较好的误码性能。并比较了4 种数字调制方式下O FDM 系统的误码性能。
上传时间: 2014-01-22
上传用户:aeiouetla
ITU规范G.704。E1帧结构定义。Synchronous frame structures used at 1544, 6312, 2048, 8448 and 44 736 kbit/s hierarchical levels
标签: Synchronous structures frame 1544
上传时间: 2016-03-24
上传用户:lnnn30
英文版G.729语音压缩标准。 GENERAL ASPECTS OF DIGITAL TRANSMISSION SYSTEMS CODING OF SPEECH AT 8 kbit/s USING CONJUGATE-STRUCTURE ALGEBRAIC-CODE-EXCITED LINEAR-PREDICTION (CS-ACELP)
标签: TRANSMISSION GENERAL ASPECTS DIGITAL
上传时间: 2016-09-29
上传用户:15071087253
Profibus DP software slave for MSP430F2252. Tested on Siemens S7 with 19200 and 93750 kbit
标签: Profibus software Siemens Tested
上传时间: 2014-09-07
上传用户:zsjzc
高速发展的DSP技术为语音信号处理领域提供了良好的发展平台,使得实时实现各种复杂的算法称为可能。G.729语音编码是国际电信联盟(ITU-T)于1996年获准通过的采用共轭结构代数码激励线性预测技术的具有8 kbit/s码速率的语音算法建议,广泛应用于数字移动通信、IP电话和数字卫星通信中。本文研究了G.729语音编码原理和在TMS320C5416定点DSP芯片上实时实现该编码器过程中的软、硬件设计。主要涉及有以下几方面内容: 1.介绍语音编码技术和DSP技术的发展概况。 2.研究了基于CELP结构的G.729编码的算法原理。 3.根据G.729声码器实时实现的需要,介绍硬件平台的组成,研究了系统软件的设计和基于算法和实时需要的软件优化。 4.利用DSP代码调试工具对系统性能进行分析,得出测试结果。
上传时间: 2013-07-11
上传用户:woshiayin
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
The NCV7356 is a physical layer device for a single wire data linkcapable of operating with various Carrier Sense Multiple Accesswith Collision Resolution (CSMA/CR) protocols such as the BoschController Area Network (CAN) version 2.0. This serial data linknetwork is intended for use in applications where high data rate is notrequired and a lower data rate can achieve cost reductions in both thephysical media components and in the microprocessor and/ordedicated logic devices which use the network.The network shall be able to operate in either the normal data ratemode or a high-speed data download mode for assembly line andservice data transfer operations. The high-speed mode is onlyintended to be operational when the bus is attached to an off-boardservice node. This node shall provide temporary bus electrical loadswhich facilitate higher speed operation. Such temporary loads shouldbe removed when not performing download operations.The bit rate for normal communications is typically 33 kbit/s, forhigh-speed transmissions like described above a typical bit rate of83 kbit/s is recommended. The NCV7356 features undervoltagelockout, timeout for faulty blocked input signals, output blankingtime in case of bus ringing and a very low sleep mode current.
上传时间: 2013-10-24
上传用户:s蓝莓汁
IA4420 工作在315/433/868/915MHz 频段(IA4421 工作在433/868/915MHz 频段); 2. 低电压工作,工作电压2.2V~5.4V; 3. 低功耗模式,待机电流0.3uA; 4. 调制模式FSK,并具备高度集成的PLL; 5. 低发射功率、高接收灵敏度设计,发射功率5~10 dbm 可调,接收灵敏度-109 dbm; 6. 内置时钟输出,可省掉MCU 的晶振; 7. 传输数据率高,数字信号可达115.2 kbit/s,模拟信号可达256 kbit/s; 8. 发射频偏与接收带宽可调; 9. 内部有数字滤波器,并可以根据要求选择不同的方式; 10. SPI 的控制接口,方便使用; 11. 接收时有数据同步码识别器,系统检测同步码后将后面的数据输出; 12. 有16 位的收发缓存器,用来缓存接收到或要发送的数据(接收数据有两种方式,用户可以按需选择); 13. 有低电压检测器,从2.2-5.4V 可调; 14. 有定时唤醒功能,定时时间可达几天; 15. 天线的兼容性强,有天线自动调节功能,并可采用PCB 或外置天线; 16. 工作温度范围-40~85,储存温度范围-55~125℃; 17. 采用微小TSSOP16 封装。
上传时间: 2014-10-30
上传用户:aa17807091
ITU-T G.729语音压缩算法。 description: Fixed-point description of commendation G.729 with ANNEX B Coding of Speech at 8 kbit/s using Conjugate-Structure Algebraic-Code-Excited Linear-Prediction (CS-ACELP) with Voice Activity Decision(VAD), Discontinuous Transmission(DTX), and Comfort Noise Generation(CNG).
标签: description commendation Fixed-point 729
上传时间: 2014-11-23
上传用户:thesk123
AT88SC0104(at88sc,at88sc0104c)烧录器软件下载,压缩包里面附带使用说明书 AT88SC0104C 1-kbit 用户存储器, 带身份认证和加密 AT88SC0204C 2-kbit 用户存储器, 带身份认证和加密 AT88SC0404C 4-kbit 用户存储器, 带身份认证和加密 AT88SC0808C 8-kbit 用户存储器, 带身份认证和加密 AT88SC1616C 16-kbit 用户存储器, 带身份认证和加密 AT88SC3216C 32-kbit 用户存储器, 带身份认证和加密 AT88SC6416C 64-kbit 用户存储器, 带身份认证和加密 AT88SC12816C 128-kbit 用户存储器,带身份认证和加密 AT88SC25616C 256-kbit 用户存储器,带身份认证和加密
上传时间: 2016-04-03
上传用户:x4587