基于單DSP的VoIP模擬電話適配器研究與實(shí)現(xiàn):提出和實(shí)現(xiàn)了一種新穎的基于單個(gè)通用數(shù)字信號(hào)處理器(DSP)的VoIP模擬電話適配器方案。DSP的I/O和存儲(chǔ)資源非常有限,通常適于運(yùn)算密集型應(yīng)用,不適宜控制密集型應(yīng)用[5]。該系統(tǒng)高效利用單DSP的I/O和片內(nèi)外存儲(chǔ)器資源,采用μC/OS-II嵌入式實(shí)時(shí)操作系統(tǒng),支持SIP和TCP-UDP/IP協(xié)議,通過LAN或者寬帶接入,使普通電話機(jī)成為Internet終端,實(shí)現(xiàn)IP電話。該系統(tǒng)軟硬件結(jié)構(gòu)緊湊高效,運(yùn)行穩(wěn)定,成本低,具有廣闊的應(yīng)用前景。關(guān)鍵詞:模擬電話適配器;IP電話;數(shù)字信號(hào)處理器;μC/OS-II 【Abstract】This paper presents a VoIP ATA solution based on a single digital signal processor (DSP). DSPs are suitable for arithmetic-intensiveapplication and unsuitable for control-intensive application because of the limitation of I/O and memory resources. This solution is based on a 16-bitfixed-point DSP and μC/OS-II embedded real-time operating system. It makes good use of the limited resources, supports SIP and TCP-UDP/IPprotocol. It can connect the analog telephone to Internet and realize the VoIP application. This system has a great future for its high efficiency andlow cost.【Key words】Analog telephone adapter (ATA); Voice over Internet protocol (VoIP); Digital signal processor (DSP); μC/OS-II Research and Implementation of VoIPATA Based on Single DSP
上傳時(shí)間: 2013-11-20
上傳用戶:Wwill
Abstract: There are many things to consider when designing a power supply for a field-programmablegate array (FPGA). These include (but are not limited to) the high number of voltage rails, and thediffering requirements for both sequencing/tracking and the voltage ripple limits. This application noteexplains these and other power-supply considerations that an engineer must think through whendesigning a power supply for an FPGA.
上傳時(shí)間: 2013-11-10
上傳用戶:iswlkje
Xilinx is disclosing this user guide, manual, release note, and/or specification (the "Documentation") to you solely for use in the developmentof designs to operate with Xilinx hardware devices. You may not reproduce, distribute, republish, download, display, post, or transmit theDocumentation in any form or by any means including, but not limited to, electronic, mechanical, photocopying, recording, or otherwise,without the prior written consent of Xilinx. Xilinx expressly disclaims any liability arising out of your use of the Documentation. Xilinx reservesthe right, at its sole discretion, to change the Documentation without notice at any time. Xilinx assumes no obligation to correct any errorscontained in the Documentation, or to advise you of any corrections or updates. Xilinx expressly disclaims any liability in connection withtechnical support or assistance that may be provided to you in connection with the Information.
標(biāo)簽: Virtex FPGA PCB 設(shè)計(jì)手冊(cè)
上傳時(shí)間: 2014-01-13
上傳用戶:竺羽翎2222
Xilinx is disclosing this user guide, manual, release note, and/or specification (the “Documentation”) to you solely for use in the development of designs to operate with Xilinx hardware devices. You may not reproduce, distribute, republish, download, display, post, or transmit the Documentation in any form or by any means including, but not limited to, electronic, mechanical, photocopying, recording, or otherwise, without the prior written consent of Xilinx. Xilinx expressly disclaims any liability arising out of your use of the Documentation. Xilinx reserves the right, at its sole discretion, to change the Documentation without notice at any time. Xilinx assumes no obligation to correct any errors contained in the Documentation, or to advise you of any corrections or updates. Xilinx expressly disclaims any liability in connection with technical support or assistance that may be provided to you in connection with the Information.
標(biāo)簽: CPLD
上傳時(shí)間: 2013-10-22
上傳用戶:李哈哈哈
在現(xiàn)代通信系統(tǒng)中,電話語音的頻帶被限制在300 Hz~4 kHz的范圍內(nèi),帶來了語音可懂度和自然度的降低。為了在不增加額外成本的前提下提高語音的可懂度和自然度,進(jìn)行了電話語音頻帶擴(kuò)展的研究。提出了一種改進(jìn)的基于碼本映射的語音帶寬擴(kuò)展算法:在碼本映射的過程中,使用加權(quán)系數(shù)來得到映射碼本。客觀測(cè)試結(jié)果表明,用此算法得到的寬帶語音的譜失真度比用一般的碼本映射降低至少2%。主觀測(cè)試結(jié)果表明,用此算法得到的寬帶語音具有更好的可懂度和自然度。 Abstract: In modern communication systems, the bandwidth of telephone speech is limited from 300Hz to 4 kHz, which reduces the intelligibility and naturalness of speech. Telephone speech bandwidth extension is researched to get wideband speech and to improve its intelligibility and naturalness, without increasing extra costs. This paper put forward an improved algorithm of speech bandwidth extension based on codebook mapping. In the process of codebook mapping, weighted coefficients were used to get mapping codebook. Objective tests show that spectral distortion of wideband speech obtained by this algorithm reduces at least 2%, comparing to conditional codebook mapping. Subjective tests show that the wideband speech obtained by this algorithm has better intelligibility and naturalness.
上傳時(shí)間: 2014-12-29
上傳用戶:15501536189
Xilinx is disclosing this user guide, manual, release note, and/or specification (the "Documentation") to you solely for use in the developmentof designs to operate with Xilinx hardware devices. You may not reproduce, distribute, republish, download, display, post, or transmit theDocumentation in any form or by any means including, but not limited to, electronic, mechanical, photocopying, recording, or otherwise,without the prior written consent of Xilinx. Xilinx expressly disclaims any liability arising out of your use of the Documentation. Xilinx reservesthe right, at its sole discretion, to change the Documentation without notice at any time. Xilinx assumes no obligation to correct any errorscontained in the Documentation, or to advise you of any corrections or updates. Xilinx expressly disclaims any liability in connection withtechnical support or assistance that may be provided to you in connection with the Information.
標(biāo)簽: Virtex FPGA PCB 設(shè)計(jì)手冊(cè)
上傳時(shí)間: 2013-11-11
上傳用戶:zwei41
Xilinx is disclosing this user guide, manual, release note, and/or specification (the “Documentation”) to you solely for use in the development of designs to operate with Xilinx hardware devices. You may not reproduce, distribute, republish, download, display, post, or transmit the Documentation in any form or by any means including, but not limited to, electronic, mechanical, photocopying, recording, or otherwise, without the prior written consent of Xilinx. Xilinx expressly disclaims any liability arising out of your use of the Documentation. Xilinx reserves the right, at its sole discretion, to change the Documentation without notice at any time. Xilinx assumes no obligation to correct any errors contained in the Documentation, or to advise you of any corrections or updates. Xilinx expressly disclaims any liability in connection with technical support or assistance that may be provided to you in connection with the Information.
標(biāo)簽: CPLD
上傳時(shí)間: 2014-12-05
上傳用戶:qazxsw
關(guān)于FPGA流水線設(shè)計(jì)的論文 This work investigates the use of very deep pipelines for implementing circuits in FPGAs, where each pipeline stage is limited to a single FPGA logic element (LE). The architecture and VHDL design of a parameterized integer array multiplier is presented and also an IEEE 754 compliant 32-bit floating-point multiplier. We show how to write VHDL cells that implement such approach, and how the array multiplier architecture was adapted. Synthesis and simulation were performed for Altera Apex20KE devices, although the VHDL code should be portable to other devices. For this family, a 16 bit integer multiplier achieves a frequency of 266MHz, while the floating point unit reaches 235MHz, performing 235 MFLOPS in an FPGA. Additional cells are inserted to synchronize data, what imposes significant area penalties. This and other considerations to apply the technique in real designs are also addressed.
標(biāo)簽: investigates implementing pipelines circuits
上傳時(shí)間: 2015-07-26
上傳用戶:CHINA526
Design Specification Introduction Goals and Objectives GameForge is a graphical tool used to aid in the design and creation of video games. It attempts to bring game development down to a level that any computer savvy user can understand, without requiring masterful programming ability. A user with limited Microsoft DirectX and/or Visual C++ programming knowledge will be able to construct a basic, 2-D arcade game. GameForge limits the amount of actual code written by the user, if not eliminating it completely. It will also assist experienced programmers in generating the Microsoft DirectX and Microsoft Windows9x overhead necessary for basic game construction, allowing them to concentrate on more detailed game design issues and implementation.
標(biāo)簽: Specification Introduction Objectives GameForge
上傳時(shí)間: 2013-12-27
上傳用戶:wl9454
最優(yōu)化算法,應(yīng)用有限內(nèi)存擬牛頓方法(limited Memory (variable-storage)quasi-Newton method)求解高維最優(yōu)化問題,使用更多的內(nèi)存將使算法更有效。
標(biāo)簽: 優(yōu)化算法
上傳時(shí)間: 2015-08-08
上傳用戶:cuiyashuo
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