صفحه محصول - پاورپوینت انتقال صدا و تصویر در سیستم موبایل

پاورپوینت انتقال صدا و تصویر در سیستم موبایل (pptx) 40 اسلاید

دسته بندی : پاورپوینت

نوع فایل : PowerPoint (.pptx) ( قابل ویرایش و آماده پرینت )

تعداد اسلاید: 40 اسلاید

قسمتی از متن PowerPoint (.pptx) :

انتقال صدا و تصویر در سیستم موبایل 1 فهرست مطالب مقدمه آشنایی با اصطلاحات مورد استفاده در مقاله آشنایی اجمالی با ساختار شبکه موبایل ساختار NAT بررسی تجربی یک آزمایش ارزیابی و مقایسه چند نرم افزار در استفاده از روش P2P در انتقال ویدئو و صدا 2 آشنایی با ساختار کلی شبکه موبایل و پروتکلهای آن نسل های موبایل 1G 2G 2.5 G 2.75G 3G 3G-324M 3G/UMTS 3GPP ETSI 4G نحوه انتقال صدا و داده در موبایل 3 3G Compared to 2G and 2.5G services, 3G allows simultaneous use of speech and data services and higher data rates (up to 14.4 Mbit /s on the downlink and 5.8 Mbit /s on the uplink with HSPA+). To support mobile multimedia applications,3G had to deliver packet-switched data with better spectral efficiency, at far greater speeds 3G networks offer a greater degree of security than 2G predecessors. 3G networks use the KASUMI block crypto instead of the older A5/1 stream cipher. 4 3G-324M 3G-324M is the 3GPP umbrella protocol for video telephony in 3G mobile networks. The 3G-324M protocol operates over an established circuit switched connection between two communicating peers. 3G-324M is an umbrella specification to enable conversational multimedia communication over Circuit Switched (CS) networks and has been adopted by the 3GPP. 3G-324M is based on the ITU-T H.324 5 3G-324M Sub protocols ITU-T H.245 for call control ITU-T H.223 for bit streams to data packets multiplexer/ demultiplexer ITU-T H.223 Annex A and B for error handling of low and medium BER detection, correction and concealment ITU-T H.324 with Annexes A and C for operating in wireless environment 6 Scope of 3G-324M 7 3G-324M Usages The 3G-324M specification using the Circuit switched network allows delay sensitive conversational multimedia services such as: Video Conferencing for personal and business use Multimedia entertainment services Telemedicine Surveillance Live Video Broadcasting– Cable TV On-the-Go Video-on-demand (movies, news clips) 8 3G-UMTS UMTS is one of the third-generation (3G) mobile telecommunications technologies, which is also being developed into a 4G technology. It is specified by 3GPP and is part of the global ITU IMT-2000 standard The most common form of UMTS uses W-CDMA (IMT Direct Spread) as the underlying air interface but the system also covers TD-CDMA and TD-SCDMA (both IMT CDMA TDD). UMTS also covers the radio access network (UMTS Terrestrial Radio Access Network; UTRAN ), the core network (Mobile Application Part; MAP ) as well as authentication of users via USIM cards (Subscriber Identity Module). 9 3G-UMTS UMTS, using W-CDMA, supports maximum theoretical data transfer rates of 21 Mbit /s (with HSDPA),although at the moment users in deployed networks can expect a transfer rate of up to 384 Kbit/s for R99 handsets, and 7.2 Mbit /s for HSDPA handsets in the downlink connection. This is still much greater than the 9.6 Kbit/s of a single GSM error-corrected circuit switched data channel or multiple 9.6 Kbit/s channels in HSCSD (14.4 Kbit/s for CDMAOne ), and—in competition to other network technologies such as CDMA2000, PHS or WLAN—offers access to the World Wide Web and other data services on mobile devices. 10