2b-as/xgoldmon. UTRAN Procedures - 08a_UTRAN-procedures-ws11.pdf. 3G Wireless Technology Quick Guide > WCDMA Logical / Transport / Physical Channel Mapping. DecodingUMTS – rangepublic. The purpose of this wiki area is to provide a clear and concise presentation of the information given in the 3GPP UMTS/UTRAN specifications, specifically on the "Uu" interface.
Because UMTS/UTRAN inherit many concepts and subprotocols from GSM and GPRS (" Um"), some understanding of those technologies is probably a prerequisite for understanding this wiki. One of the problem with UMTS complexity is that the standard supports a lot of deployment variations. For simplicity, this wiki should probably focus on the most commonly deployed style of UMTS/UTRAN worldwide: FDD radio interface and GSM-MAP core network. Please do not just copy-paste large sections of text from the specifications themselves into the wiki. First, it's a copyright violation. To edit this wiki, you can login as user "guest" with the password "guestpass". If you have a specific question about a specific part of the specification, please put the question into the wiki using italicized text like you see here. Layer 2 ¶ UMTS / WCDMA Channels. - tutorial, or overview of the basics of UMTS / WCDMA logical, physical and transport channels.
There are many UMTS channells that are used within the UMTS system. The data carried by the UMTS / WCDMA transmissions is organised into frames, slots and channels. In this way all the payload data as well as the control and status data can be carried in an efficient manner. UMTS uses CDMA techniques (as WCDMA) as its multiple access technology, but it additionally uses time division techniques with a slot and frame structure to provide the full channel structure. A channel is divided into 10 ms frames, each of which has fifteen time slots each of 666 microseconds length. On the uplink dual channel modulation is used so that both data and control are transmitted simultaneously. The channels carried are categorised into three: logical, transport and physical channels. Logical Channels: Broadcast Control Channel (BCCH), (downlink). Paging Control Channel (PCCH), (downlink). Transport Channels: De la 2G à la 4G - La 4G : Tout ce qu'il faut savoir sur le sans fil et la mobilité.
Cette page reprend les articles Techniques.
Qu'entend-on par la 4G? La norme LTE-Advanced, aussi dénommée 4G est la norme téléphonie de 4ème Génération. Celle-ci permet d'améliorer les performances d'une communication radio-mobiles comparativement à la 3G notamment en terme de : Débits (montant et descendant) Interactivité : réduction de la latence Meilleure efficacité spectrale : L'opérateur peut couvrir une plus grande densité de population en exploitant une bande de fréquence identique à la 3G. Optimisation automatique du réseau : Les équipements 4G se configureront automatiquement pour améliorer la qualité de service offerte au particulier.
Des confusions à éviter. Ainsi, la 3G regroupe deux standards, le 3GPP et le 3GPP2. Pourquoi la 4G? Dans les faits, la 3G n'est arrivée en France qu'en 2004, la 2G en 1992 mais le téléphonie mobile n'a réellement inondé le marché qu'à la fin des années 90. Actuellement, on lit plusieurs expérimentations sur le LTE. Les années 80.