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1、<p>  附錄B:外文文獻(xiàn)及譯文</p><p>  Visual Round wireless doorbell in the voice communications system design and implementation</p><p>  First:Introduction</p><p>  Microelectronics tec

2、hnology, wireless technology and network technology for the development of modern people living environment of security, facilitate the provision of a strong technical support,This presents a smart area for the safety of

3、 the new wireless doorbell system visualization Round, On the system's overall structure and working principle and the key technology full-duplex digital voice communications for the design and realization of,Analysi

4、s of the digital transmission of voice proce</p><p>  The development of electronic, wireless and network technology provides the strong technical support for security and convenience of modern residential q

5、uarters. In this paper, we introduce a new style wireless visual inter-conversation doorbell system, which is used in the intelligent residential quarters. Then explains the structure of this system, and it’s full-duplex

6、 digital voice communication is designed and implemented. We emphasize the digital voice process in transmission, and discuss t</p><p>  Second:Features</p><p>  At present domestic doorbell has

7、 been a lot of visualization products, mainstream product is wired, one-way voice and Simulation. Visual Round wireless doorbell system combines computer technology, wireless communications and digital signal processing

8、technology used in high-frequency wireless transmitter receiver, installation without cabling, would not undermine the effectiveness decoration. Visual Round wireless doorbell system is the next generation of electronic

9、security systems, modern gar</p><p>  (1)2.4 GHz, 900MHz high-frequency signal transmission.</p><p>  (2)In the 60 m clearly within the scope of stable transmission audio and video signals at a

10、barrier such as distance is 30m.</p><p>  (3)If on the doorbell, "Ding Dong" Sound hints open automatically monitor screen</p><p>  (4)Wireless unlock, and control of the electric door

11、 lock control.</p><p>  (5)Indoor Wireless proactively monitor.</p><p>  (6)Delay shut down automatically monitoring system.</p><p>  (7)Wireless transmission, the receiver can easi

12、ly be placed, easy installation.</p><p>  (8)Wireless full-duplex voice communication.</p><p>  The system is composed of two parts: part of indoor and outdoor part. Visual Round wireless doorbe

13、ll system uses full-duplex digital wireless voice programmes, indoor and outdoor machines are corresponding to the four basic modules, including A / D / A modules from voice codec chip MC145481 completed, the speech sign

14、al processing module from the CPLD digital voice signals as well as a package of reconciliation package synchronization, thereby enhancing anti-jamming capability. wireless transmit </p><p>  Third:Voice tra

15、nsmission processing</p><p>  Although voice processing digital signal transmission than analog signals have great advantages, but digital signal analog signal difficult than receiving, processing requiremen

16、ts more stringent than the analog signal, with the development of society, wireless communication equipment widely used, resulting in increased electromagnetic interference, and advances in technology enabling wireless r

17、eceiver continuously improve receiver sensitivity, wireless receiver in the corresponding sent equipmen</p><p>  To establish stable communication, a standard wireless data transmission frame should include

18、at least the following parts:</p><p>  (1) Jumping code: in the receiving establishment phase, providing reception threshold level, its length and hardware relevant data, wireless doorbell system visualizati

19、on Talkback used in the x99 is 0.</p><p>  (2) redundant code: According to experience, usually adopts a 0xff or 0xff, 0x66 results were relatively good, and the establishment of communication to correct err

20、ors arising from the phase-out-of-step serial receiver, in the slow speed (<19200 bps), the two often use L-redundant code is not adopted in the design.</p><p>  (3)Synchronous Code: used for frame synchr

21、onization, data transfer and use of relatively low-bit-rate code word, and in order to improve reliability, and a 2-byte or 2 bytes above synchronous code words such as 0xaa 0xbb. Visual Round wireless doorbell system is

22、 used in the 0xCCCCCC.</p><p>  (4)Data: users want to transfer data to improve the reliability of communications, the proposed Manchester encoding the data or using DPCM send, and data validation. Mancheste

23、r encoding or used in the DPCM transmitted, the length of the data generally should not exceed 256 bytes; on the contrary, should not exceed 64 bytes. But speaking in the wireless doorbell visual system, digital voice wi

24、reless transmitter module maximum data transmission rate of 76.8 kbps, but the voice from the A / D chip </p><p>  Software using top-down design methodology, a total of five documents: the top-level documen

25、ts were, transmit modules accept modules, digital phase-locked loop and frame state machine. Top-level document for the system clock with a 2048 kHz voice codec interface chip MC145481, including sending and receiving of

26、 two functional modules L module which is sent to send data in the original data before adding header, voice communications frame 0x99 first, 0xCC, 0xCC, 0xCC, followed by the control sign</p><p>  As voice

27、signals are relatively weak in general, according to M u/A code of law, may be even longer, "1", so that the receiver can not extract the correct information in sync, so we carried out a simple voice and data h

28、andling, even if "1" is greater than the number eight, an eighth reverse, namely, "1" to "0." As one of the quantitative data sampling points last a minimum weights, this will not deal with

29、the impact of.</p><p>  Last:Concluding remarks</p><p>  Based on the visual-speaking wireless doorbell system, and its two-way voice communications for the design and realization, it is has bee

30、n tested and empty distance of 60 m, 30 m to obstructions, clear voice L test results show that the design of a performance stable and reliable, voice clear, simple design, and other features, the value of L practical co

31、urse of the programme in this paper on the properties have yet to be improved, then we have to do the work is the image of real-time digital in</p><p><b>  中文譯文</b></p><p>  可視對講門鈴系統(tǒng)

32、中語音通信的設(shè)計(jì)與實(shí)現(xiàn)</p><p><b>  一、引言</b></p><p>  微電子技術(shù)、無線技術(shù)和網(wǎng)絡(luò)技術(shù)的發(fā)展為現(xiàn)代人們居住環(huán)境的安全、方便提供了有力的技術(shù)支撐,由此介紹了一種用于智能小區(qū)安全的新型的無線可視對講門鈴系統(tǒng),闡述了該系統(tǒng)的總體結(jié)構(gòu)和工作原理,并對其中的關(guān)鍵技術(shù)全雙工數(shù)字語音通信進(jìn)行了設(shè)計(jì)和實(shí)現(xiàn),分析了數(shù)字語音在傳輸中的處理,討論了幀結(jié)構(gòu)的

33、設(shè)計(jì),并在CPLD 中實(shí)現(xiàn)了無線可視對講門鈴系統(tǒng)的幀同步,最后對所做的樣機(jī)系統(tǒng)進(jìn)行了無對所做的樣機(jī)系統(tǒng)進(jìn)行了實(shí)地測試,性能穩(wěn)定、可靠,語音清晰,具有很好的實(shí)用價(jià)值。</p><p>  電子貿(mào)易的發(fā)展,無線和網(wǎng)絡(luò)技術(shù)為安全性與方便性的現(xiàn)代住宅小區(qū)提供了強(qiáng)有力的技術(shù)支撐。在這篇文章中,我們引入一個(gè)新的作風(fēng),無線視覺跨交談門鈴系統(tǒng),它可以用來在智能化住宅小區(qū)。我們引入一個(gè)新的作風(fēng),無線視覺跨交談門鈴系統(tǒng),它可以用來在

34、智能化住宅小區(qū)。然后解釋了結(jié)構(gòu)這個(gè)制度,它的全部全雙工數(shù)字語音通信的設(shè)計(jì)和實(shí)施。我們強(qiáng)調(diào)在傳送數(shù)字化語音過程中,并討論了結(jié)構(gòu)設(shè)計(jì)的框架,以及幀同步實(shí)現(xiàn)的CPLD 。最后,測試結(jié)果表明,一個(gè)穩(wěn)定和可靠的質(zhì)量,清晰的語音和相當(dāng)?shù)膶?shí)用價(jià)值。</p><p>  隨著微電子技術(shù)、無線技術(shù)和網(wǎng)絡(luò)技術(shù)的飛速發(fā)展,人們對于居住環(huán)境的安全、方便提出了越來越高的要求,因此智能化小區(qū)隨之出現(xiàn)L隨著改革開放的深入和市場經(jīng)濟(jì)的迅速發(fā)展,

35、城市流動(dòng)人口大量增加,帶來諸多不安定因素,可視門鈴等安全防范裝置得到了廣泛應(yīng)用。目前國內(nèi)已經(jīng)有很多可視門鈴方面的產(chǎn)品,主流產(chǎn)品是有線方式,單向語音且模擬。無線可視對講門鈴系統(tǒng)結(jié)合微機(jī)技術(shù)、無線通信技術(shù)和數(shù)字信號處理技術(shù),采用在高頻段無線發(fā)送接收,安裝時(shí)無需布線,不會(huì)破壞裝修效果。本文主要針對無線可視對講門鈴系統(tǒng)中的關(guān)鍵技術(shù)——語音通信進(jìn)行設(shè)計(jì)和實(shí)現(xiàn)。</p><p><b>  二、功能特點(diǎn)</b

36、></p><p>  無線可視對講門鈴系統(tǒng)的功能特點(diǎn)無線可視對講門鈴系統(tǒng)是新一代電子安全防范系統(tǒng),是現(xiàn)代花園、山莊、別墅理想的安全防范裝置。家人可以在室內(nèi),通過屏幕看圖像、語音對講,遠(yuǎn)距離了解門外的情況,準(zhǔn)確判斷來訪者的身份,決定是否開門接待,保障家庭的人身和財(cái)產(chǎn)安全L該系統(tǒng)采用模數(shù)混合技術(shù),即語音數(shù)字,視頻模擬,是將來全數(shù)字無線可視對講門鈴系統(tǒng)的一個(gè)過渡,該統(tǒng)的主要功能特點(diǎn)有:</p>&

37、lt;p>  (1) 2. 4 GHz,900MHz 高頻信號傳送。</p><p>  (2) 能在60 m 范圍以內(nèi)清晰地傳送穩(wěn)定的音、視頻信號; 如隔有障礙物,距離則為30 m 。</p><p>  (3) 如有人按門鈴,則有“叮咚”聲提示并自動(dòng)打開監(jiān)視畫面。</p><p>  (4) 無線開鎖,控制門口的電控鎖。</p><p&

38、gt;  (5) 室內(nèi)機(jī)無線主動(dòng)監(jiān)視。</p><p>  (6) 延時(shí)工作,自動(dòng)關(guān)閉監(jiān)控系統(tǒng)。</p><p>  (7) 無線傳送,可隨意放置接收機(jī),安裝方便。</p><p>  (8) 無線全雙工語音通信。</p><p>  該系統(tǒng)由兩部分組成: 室內(nèi)機(jī)部分和室外機(jī)部分室內(nèi)機(jī)主要由語音芯片、數(shù)字信號處理模塊、單片機(jī)AT89C51,顯

39、示屏和2.4G 接收模塊及無線收發(fā)模塊等組成。無線可視對講門鈴系統(tǒng)采用無線全雙工數(shù)字語音方案,室內(nèi)室外機(jī)都由四個(gè)相對應(yīng)的基本模塊組成,其中A/D/A 模塊由語音編解碼芯片MC145481 完成,語音信號處理模塊由CPLD 對數(shù)字語音信號進(jìn)行打包和解包以及同步處理,從而提高抗干擾能力。無線發(fā)射/接收模塊對處理后的數(shù)字信號進(jìn)行調(diào)制和解調(diào),使其適合無線信道的傳輸。</p><p><b>  三、語音傳輸處理

40、</b></p><p>  語音傳輸處理雖然數(shù)字信號比模擬信號有很大的優(yōu)點(diǎn),但是數(shù)字信號比模擬信號難于接收,處理的要求比模擬信號更為嚴(yán)格。隨著社會(huì)的發(fā)展,無線通信設(shè)備的廣泛使用,導(dǎo)致電磁干擾加??;而技術(shù)的進(jìn)步使無線接收機(jī)的接收靈敏度不斷提高,所以無線接收機(jī)在相應(yīng)的發(fā)送設(shè)備不作時(shí)也會(huì)有數(shù)據(jù)解調(diào)輸出。無線通信中必須按數(shù)據(jù)幀分組傳輸數(shù)據(jù),并且必須采可靠的幀同步方式來保證從混亂的數(shù)據(jù)中將合法的數(shù)據(jù)幀識(shí)別出來

41、。 幀同步可以采用位同步或碼同步。位同步對硬件設(shè)備要求比較高,實(shí)現(xiàn)比較困難,一般很少使用而多采用碼同步。同步碼的選擇應(yīng)該保證同步碼與數(shù)據(jù)重碼概率盡可能低,以便在一般的應(yīng)用中,協(xié)議不需要進(jìn)行重碼的轉(zhuǎn)義設(shè)計(jì); 如果幀之間設(shè)置有超時(shí)定時(shí)器并且傳輸協(xié)議規(guī)定了幀數(shù)據(jù)長度,那么幀同步碼則可以任意選擇,一般選擇0xAA,0x55之類0- 1均勻分布的數(shù)據(jù),并且為了提高可靠性,往往選擇多字節(jié)的幀同步碼,比如0xAA,0xBB (兩字節(jié)幀同步碼)。<

42、;/p><p>  要建立穩(wěn)定的通信,一個(gè)標(biāo)準(zhǔn)的無線數(shù)據(jù)傳輸幀應(yīng)該至少包括以下部分:</p><p>  (1) 前導(dǎo)碼:用在接收建立階段,提供接收的門限電平,其數(shù)據(jù)長度與硬件有關(guān),無線可視對講門鈴系統(tǒng)中采用的是0x99。</p><p>  (2) 冗余碼:根據(jù)經(jīng)驗(yàn),通常采用0xff 或者0xff,0x66的效果比較好,用來糾正通信建立階段位錯(cuò)誤引起的串口接收失步,在

43、低速時(shí)(< 19 200bps),往往使用兩個(gè)冗余碼L本設(shè)計(jì)中不采用。</p><p>  (3) 同步碼:用來建立幀同步,采用與傳輸數(shù)據(jù)重碼率比較低的碼字,并且為了提高可靠性,推薦采用2字節(jié)或2字節(jié)以上的同步碼字,比如0xaa,0xbb。無線可視對講門鈴系統(tǒng)中采用的是0xCCCCCC。</p><p>  (4) 數(shù)據(jù):用戶要傳輸?shù)臄?shù)據(jù),為提高通信的可靠性,建議對數(shù)據(jù)進(jìn)行曼徹斯特編

44、碼或采用DPCM方式發(fā)送,并對數(shù)據(jù)進(jìn)行校驗(yàn)。在采用曼徹斯特編碼或DPCM 方式傳輸中,數(shù)據(jù)長度一般不要超過256字節(jié);反之,不要超過64 字節(jié)。但是在無線可視對講門鈴系統(tǒng)里,數(shù)字語音無線發(fā)射模塊的最高傳輸數(shù)據(jù)速率為76.8 kbps,但是語音從A/D 芯片出來的數(shù)據(jù)就有64 kbps,由于受到CPLD 容量以及發(fā)射天線帶寬兩方面因素的制約,我們沒有采取復(fù)雜的編碼處理。</p><p>  其中0x99為前導(dǎo)碼,用

45、于初始位同步和接收狀態(tài)機(jī)復(fù)位,0xCCCCCC為數(shù)據(jù)幀同步碼,幀同步碼后面八位用來傳控制碼。無線可視對講門鈴系統(tǒng)中的控制碼個(gè)數(shù)不多,室內(nèi)到室外有3個(gè),即主動(dòng)監(jiān)視、開鎖、摘掛機(jī)。 室外到室內(nèi)的控制信號只有一個(gè)呼叫按鍵,所以我們設(shè)計(jì)時(shí),將幀同步碼后的一個(gè)字節(jié)留給傳輸控制信號,在控制信號后面再緊跟以字節(jié)為單位的語音數(shù)據(jù)。</p><p>  軟件采用自頂向下設(shè)計(jì)方法,一共由五個(gè)文件組成:分別是頂層文件、發(fā)送模塊、接受模

46、塊、數(shù)字鎖相環(huán)和幀狀態(tài)機(jī)。頂層文件的系統(tǒng)時(shí)鐘為2048 kHz。具有與語音編解碼芯片MC145481 的接口,包含發(fā)送和接收兩個(gè)子功能模塊L其中發(fā)送模塊是為了發(fā)送數(shù)據(jù),在原始數(shù)據(jù)前添加幀頭,語音通信的幀頭為0x99,0xCC,0xCC,0xCC,后面跟控制信號字節(jié),再跟以字節(jié)為單位的語音數(shù)據(jù)L 接收模塊是為了檢測控制和語音信號,相對復(fù)雜一些,包括數(shù)字鎖相環(huán)和幀狀態(tài)機(jī)兩狀態(tài),如果檢測到0xCC,由狀態(tài)0,進(jìn)入狀態(tài)1;如果下一個(gè)字節(jié)也是0x

47、CC,由狀態(tài)1,進(jìn)入狀態(tài)2,否則返回狀態(tài)0; 如果第3個(gè)字節(jié)還是0xCC,由狀態(tài)2 進(jìn)入狀態(tài)3,進(jìn)入同步態(tài),否則返回狀態(tài)0L其中數(shù)字鎖相環(huán)是進(jìn)行位同步。</p><p>  由于語音信號一般都比較微弱,根據(jù)M u/A 律的編碼規(guī)律,有可能會(huì)出現(xiàn)長連“1”的情況,從而使得接收端無法提取正確的位同步信息,所以我們對語音數(shù)據(jù)進(jìn)行了簡單的處理,若連“1”個(gè)數(shù)大于或等于8,則第八個(gè)1 進(jìn)行反向,即“1”變?yōu)椤?”。由于一個(gè)

48、采樣點(diǎn)的量化數(shù)據(jù)最后一位權(quán)值最小,所以這樣處理不會(huì)帶來什么影響。</p><p><b>  結(jié)束語</b></p><p>  本文基于無線可視對講門鈴系統(tǒng),對其雙向語音通信進(jìn)行了設(shè)計(jì)和實(shí)現(xiàn),現(xiàn)已經(jīng)通過測試,空曠距離達(dá)60m ,有障礙物時(shí)30m ,語音清晰。測試結(jié)果表明本設(shè)計(jì)方案具有性能穩(wěn)定可靠、語音清晰、設(shè)計(jì)簡單等特點(diǎn),具有實(shí)用價(jià)值L當(dāng)然本文提出的方案在性能上還有

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