Tài liệu Điện thoại di động băng thông rộng không dây P4 pdf

... of additional 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. ... the radio interface and the management of the radio interface. In particular, the protocols across the MT – AN interface support the transfer of detailed radio-related information to co...

Ngày tải lên: 26/01/2014, 15:20

... multimedia. 4.2.2.5 Next generation of WAP The next generation of WAP will include: † XHTML † TCP † colour graphics † animation † large file downloading † location-smart services † streaming media † ... ‘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...

Ngày tải lên: 26/01/2014, 15:20

... 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. ... Fuelled by many emerging technologies including digital signal processing, software definable radio, intelligent antennas, superconductor devices as well as digital transceiver, the fut...

Ngày tải lên: 21/01/2014, 18:20

... segmentation. UMTS Air Interface 21 Table 2.2.2 Coding schemes for transport channels in FDD Transport channel Coding scheme Coding rate Convolutional coding Turbo coding No coding CC TC BCH X ––1/2 – PCH X ––1/2 ... dependent on the channel coding scheme. The following channel coding schemes can be applied to transport channels: † convolutional coding † turbo coding † no coding. The coding s...

Ngày tải lên: 21/01/2014, 18:20

... field indicates the common logical channel type, or if a dedicated logical channel is used. † UE Id Mux: for dedicated type logical channels, the UE Id field in the MAC header is used to distinguish ... (OCCCH): bi-directional channel for transmitting control information between UEs. † ODMA Dedicated Control Channel (ODCCH): a point-to-point bi-directional channel that transmits dedicated contr...

Ngày tải lên: 21/01/2014, 18:20

... radio multiplexing technology, which deals with the way the radio resources are divided and allocated to several mobile users. However, W-CDMA also speci- fies some aspects related to the radio ... each one possibly based on different RAN technology. 3.4.7.2 Independence between the transport network and radio access network As indicated in Figure 3.13(a), the radio access network is typically...

Ngày tải lên: 26/01/2014, 15:20

... networks, automatic service discovery will be a very important feature in future wireless network scenarios. With service discovery, devices may automatically discover network services including their properties, ... ingredients, for example a MP3 piece of music can be charged with micropayments assigning revenue directly to the musicians. Emerging Wireless Applications and Protocols 259 ‘Ope...

Ngày tải lên: 26/01/2014, 15:20

... volumes measured over a 200-m distance Broadband Wireless Mobile: 3G and Beyond282 Figure 5.11 Cumulative distributions of the path losses for different traffic conditions (h b ¼ 4m,h m ¼ 1.3 m, ... from the direct wave and the wave reflected off the ground and inco- herent components. As noted by Durgin et al. [25], these additive signals produce a distribu- tion in which deeper fading occurs...

Ngày tải lên: 26/01/2014, 15:20

... cellular radio systems. However, designing a teletraffic profile is exceedingly difficult because the teletraffic volume differs in different regions and districts, and it also varies, depending on ... is important. Code division multiple access (CDMA) is used in IMT-2000. For time division multiple access (TDMA), a lot of research on technology to counter fading has been studied. It also has ......

Ngày tải lên: 26/01/2014, 15:20

... when not applying site diversity, successful reception rate is essentially the same for all regions and fair service can be provided. Accordingly, the application of site diversity reception generates ... and downlink of cellular radio systems are not coincident because these system structures are different. When traffic is uneven, it influences on commu- nication quality differently for the tw...

Ngày tải lên: 26/01/2014, 15:20