into account the planning coverage probability given in DTTB Handbook 2002 edition of 70% and 95%, also adopted into ITU-R Recommendations. 17 MER distribution 18 Field strength distribution 2.3.2 VHF case 2.3.2.1 Transition points on cBER axis Through consideration based on the same set of measurement values as above for VHF case, it can be seen that more than 99% of the cBER values falls between 2E-2 and 2E-5. It should be remembered that for 64QAM modulation and CR = 3/4 in Gaussian channel, 2E-2 before Viterbi decoding corresponds to the QEF value of 2E-4 after Viterbi decoding. The quasi-linear shape of Fig. 19 in the range 2E-2 and 2E-5 suggests, as for the UHF band, the adoption for a transition point of a linear scale with a spacing step of 10 between each class. 19 cBER classification 2.3.2.2 Transition points on field strength axis Figures 20 and 21 show respectively the of MER and field strength. Although the correlation index is only moderate with a numerical value of 0.59, both figures have a similar shape. The greater the field strength, the greater the robustness against noise and in band interference. The greater the MER, the lower the noise, in band interference and echoes, artificial and natural, falling outside guard interval. The transition points related to the field strength have been chosen taking into account the planning coverage probability given in DTTB Handbook 2002 Edition of 70% and 95%, also adopted into ITU-R Recommendations. 20 MER distribution 21 Field strength distribution
into account the planning coverage probability given in DTTB Handbook 2002 edition of 70% and 95%, also adopted into ITU-R Recommendations. 17 MER distribution 18 Field strength distribution 2.3.2 VHF case 2.3.2.1 Transition points on cBER axis Through consideration based on the same set of measurement values as above for VHF case, it can be seen that more than 99% of the cBER values falls between 2E-2 and 2E-5. It should be remembered that for 64QAM modulation and CR = 3/4 in Gaussian channel, 2E-2 before Viterbi decoding corresponds to the QEF value of 2E-4 after Viterbi decoding. The quasi-linear shape of Fig. 19 in the range 2E-2 and 2E-5 suggests, as for the UHF band, the adoption for a transition point of a linear scale with a spacing step of 10 between each class. 19 cBER classification 2.3.2.2 Transition points on field strength axis Figures 20 and 21 show respectively the of MER and field strength. Although the correlation index is only moderate with a numerical value of 0.59, both figures have a similar shape. The greater the field strength, the greater the robustness against noise and in band interference. The greater the MER, the lower the noise, in band interference and echoes, artificial and natural, falling outside guard interval. The transition points related to the field strength have been chosen taking into account the planning coverage probability given in DTTB Handbook 2002 Edition of 70% and 95%, also adopted into ITU-R Recommendations. 20 MER distribution 21 Field strength distribution