Sunday, September 13, 2009

BCCH data uncovered

BCCH data uncovered
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The data found in the elementary file broadcast control channel (EFBCCH) 7F20:6F74 / 7F21:6F74 can provide useful data relating to a geographical radio area when combined with location area information data.

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Method for translating BCCH information data. The question is, is the translation below to find the BCCH frequencies correct and what have I not mentioned below? You will need copies of GSM11.11, GSM03.03, GSM04.08 as well as understanding coding schemes.
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FIGURE 1 What the Standard states:
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FIGURE 2 What that means:
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FIGURE 3 Harvested data from a Orange SIM Card read:
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FIGURE 4 Translating the hex output to binary:
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FIGURE 5 Converting to decimal digits which translates again and corresponds to GSM assigned uplink/downlink frequencies:
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BCCH Frequencies (ARFCN)
761 765 766 774 781 782 786 787 789 790 797 799 801 803 806 813 816 825 828 829 838 846 847 849 869
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FIGURE 6 Corroborating the conversion using another tool:
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More on Cell Site Analysis: http://cellsiteanalysis.blogspot.com