年10月21日 3G SYSTRA 3G System Training Service Description CTXX Issue en Nokia Networks Oy 错误！使用“开始” 应用于要在此处显示的文字. 3G SYSTRA. Introduction to 3G & UMTS Identify what is meant by the term 3G and briefly outline the work completed by the specification bodies. Furthermore. Directory: 3G/4G develop. Plat: PDF Size: KB Downloads: 4. Upload time: Uploader: joyraj. Description: This book on 3G system.
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The first is a call originating from the fixed network. It identifies the called subscriber on the basis of the MSISDN and then checks its database to determine systta subscriber’s location. Instead of reflecting the signal, these obstacles attenuate the signal. This means that the bit rate has to be converted at some point after the signal has been received by the BTS and before it is sent to other networks.
The following list covers most of the common services, as well as the essential supplementary services.
Toolkit Drive survey There are of course advantages and disadvantages with each of these information sources. The other group is Bearer Services, which sjstra the capability of transmitting signals between a GSM network access point and an appropriate access point in the terminating network.
00_Table of Contents 3G SYSTRA(Jan-06)
Thus a mobile station and the base transceiver station receives the same signal more than once. The part responsible for taking these messages from one network element to another network element is known as the Message Transfer Part MTP. Sysrra is the group switch. It appears systrx we are able to put in data from three more PCM lines by multiplexing.
This protocol is known as LAP-Dm where the “m” denotes modified. Four of the most essential categories are listed below.
00_Table of Contents 3G SYSTRA(Jan) – [PDF Document]
All these three elements are basically databases that hold various types of information. Roaming agreements between several operators were established. The latter allows the use of the network resources only.
Location update procedures In this way, the network can keep track of the subscriber all the time, however, that is only a part of the job! A VLR database is always temporary in the sense that the data is held as long as the subscriber is within its service areawhereas the HLR maintains a permanent register of the subscribers.
It is necessary to define the network performance level, for instance the intended capacity of the switching network. To sum up, the main functions of NSS are: An essential part of the planning of microwave links is to make sure that it is possible to get free line of sight between different elements for instance between BTS and BSC sites.
As you can see from the picture below, there are three different types of BTS configurations, omnidirectional, 2 sectorised and 3 sectorised BTSs. There are no recommendations on the end user terminals. Operator specific 32 bit binary number. Therefore, a converter has to be provided in the network to change the bit rate from one to another.
The information or statements given in this document concerning the suitability, capacity, or performance of the mentioned hardware or software products cannot be considered binding but shall be defined in the agreement made between Nokia Networks and the customer.
The mathematical algorithm used for this purpose is called “Viterbi equalisation”. Shadowing effect Shadowing is generally a problem in the uplink direction, because a Base Transceiver Station transmits information at a much higher power compared to that from the mobile station. The speech of the user and the ciphering key, Kc, are processed by the ciphering algorithm A5which produces the coded speech signal.
Two of them are half and full rate traffic channels. In channel coding, the user data is coded using standard algorithms. If the time slots of the TDMA frame represent the physical channels, what about the contents?
The digital values 0 and 1 are used to change one of the characteristics of an analogue radio signal in a predetermined way. Many different factors have led to a variety of signalling systems being developed in telecommunications networks.
In city areas, cells are usually smaller than in the countryside. In the case of T61 facsimile transmission, the receiver is either not aware that the incoming call is addressed to the fax and so he has to establish the nature of the call by talking with the calling party first, or the receiver knows that it is a facsimile call, but still wants to talk with the calling party.