·G.729的編解碼C源碼(使用Intel的IPP包)堪稱效率最高-g.729 arranges decodes the c source code (to use intel the ipp package) to may be called the efficiency to be highest.文件列表: G729 ....\api ....\...
·詳細(xì)說明：GSM的編解碼C源碼(使用Intel的IPP包)堪稱效率最高。-GSM arranges decodes the c source code (to use intel the ipp package) to may be called the efficiency to be highest文件列表: GSMAMR ......\api ...
This application report discusses the design of non-invasive optical plethysmographyalso called as pulsoximeter using the MSP430FG437 Microcontroller (MCU). Thepulsoximeter consists of a peripheral probe combined with the MCU displaying theoxygen saturation and pulse rate on a LCD glass. The same sensor is used for bothheart-rate detection and pulsoximetering in this application. The probe is placed on aperipheral point of the body such as a finger tip, ear lobe or the nose. The probeincludes two light emitting diodes (LEDs), one in the visible red spectrum (660nm) andthe other in the infrared spectrum (940nm). The percentage of oxygen in the body isworked by measuring the intensity from each frequency of light after it transmitsthrough the body and then calculating the ratio between these two intensities.
Designing withProgrammable Logicin an Analog WorldProgrammable logic devices revolutionizeddigital design over 25 years ago,promising designers a blank chip todesign literally any function and programit in the field. PLDs can be low-logicdensity devices that use nonvolatilesea-of-gates cells called complexprogrammable logic devices (CPLDs)or they can be high-density devicesbased on SRAM look-up tables (LUTs)
針對傳統(tǒng)集成電路（ASIC）功能固定、升級困難等缺點，利用FPGA實現(xiàn)了擴(kuò)頻通信芯片STEL-2000A的核心功能。使用ISE提供的DDS IP核實現(xiàn)NCO模塊，在下變頻模塊調(diào)用了硬核乘法器并引入CIC濾波器進(jìn)行低通濾波，給出了DQPSK解調(diào)的原理和實現(xiàn)方法，推導(dǎo)出一種簡便的引入?仔/4固定相移的實現(xiàn)方法。采用模塊化的設(shè)計方法使用VHDL語言編寫出源程序，在Virtex-II Pro 開發(fā)板上成功實現(xiàn)了整個系統(tǒng)。測試結(jié)果表明該系統(tǒng)正確實現(xiàn)了STEL-2000A的核心功能。
Abstract:
To overcome drawbacks of ASIC such as fixed functionality and upgrade difficulty, FPGA was used to realize the core functions of STEL-2000A. This paper used the DDS IP core provided by ISE to realize the NCO module, called hard core multiplier and implemented CIC filter in the down converter, described the principle and implementation detail of the demodulation of DQPSK, and derived a simple method to introduce a fixed phase shift of ?仔/4. The VHDL source code was designed by modularity method , and the complete system was successfully implemented on Virtex-II Pro development board. Test results indicate that this system successfully realize the core function of the STEL-2000A.
Single-Ended and Differential S-Parameters
Differential circuits have been important incommunication systems for many years. In the past,differential communication circuits operated at lowfrequencies, where they could be designed andanalyzed using lumped-element models andtechniques. With the frequency of operationincreasing beyond 1GHz, and above 1Gbps fordigital communications, this lumped-elementapproach is no longer valid, because the physicalsize of the circuit approaches the size of awavelength.Distributed models and analysis techniques are nowused instead of lumped-element techniques.Scattering parameters, or S-parameters, have beendeveloped for this purpose [1]. These S-parametersare defined for single-ended networks. S-parameterscan be used to describe differential networks, but astrict definition was not developed until Bockelmanand others addressed this issue [2]. Bockelman’swork also included a study on how to adapt single-ended S-parameters for use with differential circuits[2]. This adaptation, called “mixed-mode S-parameters,” addresses differential and common-mode operation, as well as the conversion betweenthe two modes of operation.This application note will explain the use of single-ended and mixed-mode S-parameters, and the basicconcepts of microwave measurement calibration.
Designing withProgrammable Logicin an Analog WorldProgrammable logic devices revolutionizeddigital design over 25 years ago,promising designers a blank chip todesign literally any function and programit in the field. PLDs can be low-logicdensity devices that use nonvolatilesea-of-gates cells called complexprogrammable logic devices (CPLDs)or they can be high-density devicesbased on SRAM look-up tables (LUTs)
針對傳統(tǒng)集成電路（ASIC）功能固定、升級困難等缺點，利用FPGA實現(xiàn)了擴(kuò)頻通信芯片STEL-2000A的核心功能。使用ISE提供的DDS IP核實現(xiàn)NCO模塊，在下變頻模塊調(diào)用了硬核乘法器并引入CIC濾波器進(jìn)行低通濾波，給出了DQPSK解調(diào)的原理和實現(xiàn)方法，推導(dǎo)出一種簡便的引入?仔/4固定相移的實現(xiàn)方法。采用模塊化的設(shè)計方法使用VHDL語言編寫出源程序，在Virtex-II Pro 開發(fā)板上成功實現(xiàn)了整個系統(tǒng)。測試結(jié)果表明該系統(tǒng)正確實現(xiàn)了STEL-2000A的核心功能。
Abstract:
To overcome drawbacks of ASIC such as fixed functionality and upgrade difficulty, FPGA was used to realize the core functions of STEL-2000A. This paper used the DDS IP core provided by ISE to realize the NCO module, called hard core multiplier and implemented CIC filter in the down converter, described the principle and implementation detail of the demodulation of DQPSK, and derived a simple method to introduce a fixed phase shift of ?仔/4. The VHDL source code was designed by modularity method , and the complete system was successfully implemented on Virtex-II Pro development board. Test results indicate that this system successfully realize the core function of the STEL-2000A.
The high defi nition multimedia interface (HDMI) is fastbecoming the de facto standard for passing digitalaudio and video data in home entertainment systems.This standard includes an I2C type bus called a displaydata channel (DDC) that is used to pass extended digitalinterface data (EDID) from the sinkdevice (such as adigital TV) to the source device (such as a digital A/Vreceiver). EDID includes vital information on the digitaldata formats that the sink device can accept. The HDMIspecifi cation requires that devices have less than 50pFof input capacitance on their DDC bus lines, which canbe very diffi cult to meet. The LTC®4300A’s capacitancebuffering feature allows devices to pass the HDMI DDCinput capacitance compliance test with ease.
