Some Important Points for Network Planning and Optimization


1. In radio signal propagation, there are two kinds of signal fading. The fading caused by buildings shadow is called Slow fading (shadow fading ) .The fading caused by multi-path is called Fast fading (Rayleigh Fading) .

1. In GSM mobile communication system, there are mainly four kinds of diversity technology: space diversity, time diversity , frequency diversity and polarization diversity.

2. Time dispersion mainly refers to the problem of co-frequency interference arising from the time difference between master signals arriving at the receiver and other multi-path signals in terms of time for transmission in space (transmission distance).

3. In a GSM 900 cellular BTS, its Tx band is 935~960 MHZ, and its Rx band is 890~915 MHZ; its duplex interval is 45 MHZ, and its Carrier Frequency interval is 200 KHZ , each Carrier Frequency containing 8 full-rate physical channels.

4. Demodulation is actually a process to reflect the change to the transferred information about such Carrier Frequency parameters as Amplitude, frequency, phase .

5. Electronic map mainly includes such three subdirectories as clutter heights vector, which keep the information ASSET can use.

6. In GSM specification, despite what frequency reuse pattern is applied, Carrier/Interference must satisfy following request. Co-frequency C/I 9 dB. Adjacent frequency C/I - 9 dB. 400KHZ deviation C/I - 41 dB. In engineering design, 3 dB more should be considered.

7. The multiple access modes now adopted in wireless communications include FDMA , TDMA , and CDMA



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