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Tài liệu Điện thoại di động mạng lưới Radio P1 doc
... Iridium LEO Satellite Sys 1997: ERMES 1995: Trunked Radio TETRA digital 1992: Data Radio Modacom 1993: PDC digital 1992: USDC digital 1991: GSM D-Netz digital Figure 1.2: Evolution of mobile radio ... E1-Netz digital Broadband Radio Satellite Radio 1984: CT1 analogue Paging Systems Cordless Telephony 1974: Eurosignal Trunked Radio CT0 analogue 1972: B-Netz analogue 1974: Private Mobile Radio 1958: ... up the market to di erent types of customers The most important standards organizations active in the mobile radio area are covered in Appendix B Physical connections over a radio channel are...
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Tài liệu Điện thoại di động mạng lưới Radio P2 doc
... are used in radio systems: • Frequency-division multiplexing (FDM) • Time-division multiplexing (TDM) • Code-division multiplexing (CDM) • Space-division multiplexing (SDM) In addition to these ... owing to distance, speed and the radio signal shadowing of stations communicating with each other 2.7.1.1 Effects of Fading A distinction is made between long-term fading and short-term fading of ... could ordinarily only reach along a direct path through transmission The effect of di raction becomes greater as the ratio of the wavelength to the dimension of the obstacle increases Di raction...
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Tài liệu Điện thoại di động mạng lưới Radio P3 pptx
... devices and, according to GSM Rec 2.06, are divided into five di erent classes depending on the allowable transmitter power; see Table 3.4 These classifications also characterize di erent types of ... during a connection Speech and data are digitally transmitted on these channels using di erent coding methods Di erent transmission capacities are required depending on the type of service used (e.g., ... guidelines for the new digital mobile radio system had already been established by the GSM group By signing the Memorandum of Understanding on the Introduction of the Pan-European Digital Mobile Communication...
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Tài liệu Điện thoại di động mạng lưới Radio P4 pptx
... the technical parameters for the radio interfaces of the digital public mobile radio systems (GSM, USDC and PDC) 318 Other Public Mobile Radio Systems Studies show that the user capacity in ... Interleaver W 32 W0 fc 4.3 CDMA Cellular Radio According to US-TIA/IS-95 309 310 Xor Xor Xor Xor Other Public Mobile Radio Systems 42 Xor Xor Modulo Addition Long Code Mask Long Code Paging-Channel ... bit Quality Encoder 9.2 kbps Indicator Tail ăÊ ăĂƠÊĂ ÔÔâĂâĐƯÔ 172, 80, 40, 16 Bits/frame 312 Other Public Mobile Radio Systems 4.3 CDMA Cellular Radio According to US-TIA/IS-95 313 20...
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Tài liệu Điện thoại di động mạng lưới Radio P5 ppt
... 5.6: UMTS channel coding 5.6.1.7 Channel Coding Most designs for the radio interface propose block coding, convolutional coding or hybrid versions of the two Convolutional coding is especially ... integrated Services with di erent rates in di erent environments should be realized with the same radio interface Depending on the duplexing method (FDD or TDD), two di erent multiple access ... channel coding for this voice data is based on asymmetrical error protection for three di erent categories of bits according to order of importance The codes used, which have di erent coding ratios...
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Tài liệu Điện thoại di động mạng lưới Radio P6 ppt
... forwarding or call diversion to another user or group is possible • Status messages can be interchanged between di erent radio units or between radio units and the system, whereby there are 30 di erent ... Mobile Radio and Packet Data Radio Licence type C Trunked radio networks for local, geographically tightly restricted areas Licence type D Countrywide trunked radio network for mobile data radio applications ... is used in pooling calls in order to distinguish between the data packets of the di erent MTs in a time-division 376 Trunked Mobile Radio and Packet Data Radio multiplexed virtual connection An...
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Tài liệu Điện thoại di động mạng lưới Radio P7 pdf
... eight di erent tone signals per Radio Identity Code (RIC) This means that a tone receiver with a RIC can produce eight di erent alarm signals • Numeric radio paging in which the receiver has a display ... caller first dials the paging number and then the suffix number of the radio paging area in which the call is to be transmitted In addition to terminals and accessories for Cityruf, radio paging ... Europe In 5th Nordic Seminar on Digital Mobile Radio Communications (DMR V), p 119, Helsinki, Finnland, Dec 1992 [4] B Walke Mobile data communications in Germany—A survey In Proceedings of 6th International...
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Tài liệu Điện thoại di động mạng lưới Radio P8 ppt
... first ever mobile radio system in which the base station as well as the mobile terminal transmit on the same radio channel Yet the two transmission directions are not separated by di erent frequencies; ... the transmission direction is changed every millisecond on the same frequency With this procedure, called Time-Division Duplex (TDD), the expensive filters required with FrequencyDivision Duplexing ... information on bit and burst synchronization Depending on the application, these subchannels are allocated di erent channel capacities in four di erent socalled multiplex frames (see Figure 8.1)...
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Tài liệu Điện thoại di động mạng lưới Radio P9 pdf
... Information Base (DIB) All data is organized as objects in a hierarchical Directory Information Tree (DIT), in which each branch can be filed in a physically separate Directory System Agent A Directory ... Local Network D2 Fixed Radio Termination Local Network D2 D2 Fixed Radio Termination D3 D3 Portable Radio Termin D4 Portable Application Fixed Radio Termination Portable Radio Termin D4 Portable ... Portable Radio Termin D4 Portable Application D2 Fixed Radio Termination D3 Portable Radio Termin Portable Radio Termin D4 Portable Application D4 Portable Application D3 Portable Radio Termin...
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Tài liệu Điện thoại di động mạng lưới Radio P10 pptx
... of the high cost per connection and the disadvantages compared with digital networks Experiments have also been made with digital mobile radio networks Studies have been conducted with systems ... Europe Frequency band [GHz] Applications 24.549 17 3.41 2.5 1.88 PMP radio relay Radio relay for Hiperlan/4 PMP radio relay PMP radio relay DECT-WLL 26.061 3.60 2.67 1.9 Channel grid [MHz] 3.5, ... System, PHS (Japan) – US Personal Access Communication System (PACS) • Digital point-to-multipoint (PMP) radio relay systems Directional antennas with, e.g., 5–12 dB gain are normally provided for...
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Tài liệu Điện thoại di động mạng lưới Radio P11 pdf
... order to unilaterally release the radio channel Radio-Channel Disconnect (CS → PS, DL) CS transmits this message to PS to release the radio channel Radio-Channel Disconnect Complete (PS → CS, UL) ... Call proceeding L3 Service channel establishment phase L3 Authentication request Authentication response L2 L2 L1 L1 L3 L3 Communication phase Radio channel disconnect L2 L2 Radio channel disconnect ... The radio frequency transmission entity RT has functions related to management of radio resources These functions include radio zone selection, radio line setup, maintenance, switching and disconnection...
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Tài liệu Điện thoại di động mạng lưới Radio P12 ppt
... four di erent types of HIPERLAN 12.1.5 The ETSI Contribution to W-ATM Standardization The standardization group ETSI RES 10 (Radio Equipment and Systems, RES), now ETSI BRAN (Broadband Radio Access ... radio interface (user plane) 12.3.3 Protocol Stack for the ATM Radio Interface Compared with the fixed network, the radio interface as a distributed ATM multiplexer requires that certain radio-specific ... transmission conditions on radio channels necessitate the use of error protection schemes to fulfil the quality of service requirements of the individual virtual connections according to the different...
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Tài liệu Điện thoại di động mạng lưới Radio P13 doc
... Coordination Function IFS (PIFS) The PIFS is used by stations operating under the PCF to gain access to the medium at the start of the CFP 700 13 Immediate access when medium is free >= DIFS DIFS ... Interframe Space DIFS = Distributed Coordination Function Interframe Space PIFS = Point Coordination Function Interframe Space Figure 13.34: Interframe space relationship Distributed Coordination Function ... frame 13.10.3.2 Distributed Coordination Function According to the DCF (see Figure 13.35), a station must sense the medium before initiating the transmission of a packet If the medium is sensed...
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Tài liệu Điện thoại di động băng thông rộng không dây P1 docx
... depicts this multi-dimensional and re-configurable radio [1], while Figure 1.6 shows its open interfaces As wireless goes multi-dimensional, different standards come out everyday for different applications ... access ‘Digital Down-Converter Broadband Wireless Mobile: 3G and Beyond Figure 1.9 Compact wireless open terminal (DDC)’, ‘Digital Up-Converter (DUC’, ADC and DAC are components of the broadband digital ... software definable and re-configurable The packet switching is distributed in the broadband packet backbone (or core network called Packet Division Multiplex – PDM) The wireless call processing, as...
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Tài liệu Điện thoại di động băng thông rộng không dây P2 pptx
... channel coding schemes can be applied to transport channels: † convolutional coding † turbo coding † no coding The coding schemes applied are the same as for the FDD mode already described Radio frame ... channels in FDD Transport channel BCH PCH RACH FACH CPCH DSCH DCH Coding scheme Convolutional coding Turbo coding No coding Coding rate CC TC X X X X X X X – – – X X X X – – – X X X X 1/2 1/2 1/2 ... sources; in UMTS these sources are either different users, different channels associated with different users or base stations The spreading process in UMTS is divided into two main parts The first...
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Tài liệu Điện thoại di động băng thông rộng không dây P3 docx
... timeslot and channelization code for TDD) may be divided between different access service classes in order to provide different priorities of RACH usage In addition it is possible for more than one ASC ... when accessing a new cell after cell reselection Dedicated Control Channel (DCCH): a point-to-point bi-directional channel that transmits dedicated control information between a UE and the network ... transmitting control information between UEs ODMA Dedicated Control Channel (ODCCH): a point-to-point bi-directional channel that transmits dedicated control information between UEs This channel...
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Tài liệu Điện thoại di động mạng lưới Radio P14 doc
... antennas Individual dipoles act as omnidirectional beams However, if groups of dipoles are used, a certain directional pattern is created through the phase di erence at the receiver, which in a distant ... the direction The directional pattern of a dipole group is dependent on the layout, phases and amplitudes of the dipoles This is exploited when phased-array antennas are used The phases of the dipoles ... Appendix B) The primary responsibility of Intelsat is to provide regular radio services worldwide, namely telephony and data links as well as the transmission and distribution of TV and radio...
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Tài liệu Điện thoại di động băng thông rộng không dây P4 pdf
... radio channels with different structure, different encoding and different modulation from the typical GSM channels These radio channels provide for increased capacity on the radio interface An overall ... network interfaces and it discusses some fundamental differences with the GSM mobile networks Section 3.4 thoroughly discusses the architecture of UMTS Terrestrial Radio Access Network (UTRAN), ... mechanisms for data transcoding to support interworking between entities using different data encoding formats The transport stratum in a 3G system, which aims at supporting multimedia services, should...
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Tài liệu Điện thoại di động băng thông rộng không dây P5 pptx
... service Macro-diversity procedure: Before a mobile is handed over to another radio channel the macro-diversity mode may be activated In this mode, the mobile is assigned an additional radio channel, ... simultaneously transmitted on two radio channels In addition, the downlink information is transmitted to the mobile by two different radio channels For this macro-diversity technique to work, the ... uplink direction is not provided because it is assumed that uplink resources on Gb are suitably dimensioned, and are significantly greater than the corresponding uplink resources on the radio interface...
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Tài liệu Điện thoại di động băng thông rộng không dây P6 pdf
... ‘cards’ on the handset display A very important advantage of WAP is that it aims to provide standardised support for wireless data applications So each handset developed according to the WAP standard ... applications plus telephony-specific features as well as providing standardised support for wireless data applications WAP is also applicable to many different wireless beares and infrastructures (see Figures ... multi-mode UI) Multimedia Mutimedia services enabled by: † † † † † † † more bandwidth (GPRS, 3G, etc) Moore’s law and handset evolution imaging – colour, standard formats, etc audio – download clips,...
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