【資料名稱】：NOKIA參數(shù)

【資料作者】：rrr

【資料日期】：2012-4

【資料語(yǔ)言】：英文

【資料格式】：DOC

【資料目錄和簡(jiǎn)介】：

31Reference Data
Ned (Customer Documentation in CD-ROM) (NED S9 available in March)
BSS Parameter Dictionary
BSC Manuals
OMC Manuals
GSM Specification
42Channel Configurations
4.12.1Time Allocation, TDMA frame structure

GSM is based on TDMA technology, which means that channels (for traffic and signalling) are separated from each other by time. This means that in radio path between the antennas of a Mobile Station (MS) and a Base Station (BTS), every channel has a specific time on each frequency during which it can act. The basic division is that one frequency is divided into eight Time Slots or Bursts and each of these Bursts is an individual channel. More precisely, each frequency has eight channels, either traffic channels or signalling channels. These eight channels have their own "time slots" related to the time for transmitting or receiving data. So, every channel has a 'right' to act every eighth time slot.

Each burst lasts 0.577 ms (exactly 15/26 ms) and thus eight bursts last 4.615 ms. There are a couple of different kinds of bursts for different purposes. The contents of the burst can vary, but the time duration of each burst is always the same. The structure of the eight bursts is called TDMA frame and the duration of a TDMA frame is called the Burst Period. The TDMA frame is the smallest and actually the basic unit of a TDMA frame structure. The whole TDMA structure is based on TDMA frames, which are placed continuously after each other's as in figure 1.