Mobile Allocation The MA is a list of hopping frequencies transmitted to a mobile every time it is assigned to a hopping physical channel. The MA-list is a subset of the CA list. The MA-list is automatically generated if the baseband hopping is used. If the network utilizes the RF hopping, the MA-lists have to … Read more
The Cell Allocation (CA) is a list of all the frequencies allocated to a cell. The CA is transmitted regularly on the BCCH. Usually it is also included in the signaling messages that command the mobile to start using a frequency hopping logical channel. The cell allocation may be different for each cell. In GSM … Read more
The requirement that the BCCH TRX must transmit continuously in all the time slots sets strict limitations on how the frequency hopping can be realized in a cell. The current solutions are Baseband Frequency Hopping (BB FH) and Synthesized Frequency Hopping (RF FH). In the baseband frequency hopping the TRXs operates at fixed frequencies. Frequency … Read more
When mobile has been selected successfully the mobile now will start reselection tasks. Perform Cell reselection measurement first Mobile will continuously make measurements on its neighboring cells (as indicated by the BA list) to initiate cell reselection if necessary. At least 5 measurement sample per neighboring cell is needed. A running average of the received … Read more
ERP,EIRP,dB and dBm calculation are Most important thing to take care in RF Planning of any site. Isotropic RF Source A point source that radiates RF energy uniformly in all directions (I.e.: in the shape of a sphere) Theoretical only: does not physically exist. Has a power gain of unity I.e. 0dBi. Effective Radiated Power … Read more
Which step to make clear before select any site at any location like equipment type, construction and link balance calculation which describe detail as below. Select Equipment Type For Site Select equipment for the cell depending on channel requirements Selection of antenna type and accessories. Locate Equipment On Site For Construction Drawing Plan of the … Read more
Here I write about selection of new site in rf planning, how step by step any new site planned is as per below. Prepare Initial Search Ring Note the latitude and longitude from planning tool. Get the address of the area from mapping software. Release the search ring with details like radius of search ring, … Read more
In a conventional non-hopping network, each call is transmitted on a single fixed frequency. This means that the interference situation in a network is also quite stable. Some calls may experience very little interference and the other calls may be interfered severely. Severe interference can be avoided by a handover, but the probability of finding … Read more
Effect in Cell Coverage Area In coverage limited cells the frequency hopping may increase the cell coverage area because of the frequency diversity gain, but since the BCCH time slot doesn’t hop, the increased coverage area is relevant only for the ongoing calls that have been successfully established and are allocated a hopping TCH. According … Read more
Cyclic vs. Random Hopping Sequences Both cyclic and random hopping modes are available in GSM. In the cyclic mode the frequencies are changed sequentially from the lowest frequency to the highest as defined in the MA-list. In random mode the frequency to be used for each burst is selected from the MA-list by a predefined … Read more