CONTENTS

 

Policy on Intellectual Property Right (IPR)     ii
Introduction     1
 
1     Objectives  4
        1.1     Why digital? − Technical considerations  4
        1.2     Why digital? − Commercial and operational considerations  4
        1.3     How digital? − Technical and operational considerations  4
       1.4      How digital? − Commercial considerations  5
 
2     DRM system aspects  6
        2.1     Key features of the system design  6
       2.2      Audio coding guidelines  7
       2.3      Transmission modes and data rates  9
                  2.3.1      DRM robustness modes  9
                  2.3.2      Spectrum occupancy types  10
                  2.3.3      DRM theoretical data rates  10
3      Modification of transmitters and antennas  12
       3.1      Principles of modifying existing transmitters − conversion to digital 13
       3.2      Converting different types of transmitter to DRM   14
       3.3      Coverage efficiency  15
       3.4      The experience of Vatican Radio  15
                  3.4.1     Modern solid-state MW transmitter 15
                  3.4.2     PDM SW transmitter 15
                  3.4.3     First-generation (GTO) PSM MW transmitter 16
                  3.4.4     Modern PSM (IGBT) SW transmitter 16
        3.5     Spectrum mask  16
       3.6      Antenna constraints  17
Load impedance bandwidth:     18
4      Coverage and frequency planning  18
        4.1     Introduction  18
                  4.1.1     Minimum usable field strength  18
                  4.1.2     Protection criteria  19
        4.2     LF/MF bands  20
                  4.2.1     Frequency bands allocated to LF and MF sound broadcasting  20
                  4.2.2     Coverage  21
                  4.2.3     Propagation  25
Influence of width of the streets     27
Attenuation occurrences due to specific urban elements     27
                  4.2.4     Frequency choice and coordination  29
                  4.2.5     Reception  29
Use of the electrical field for reception     30
Use of the magnetic field for reception     30
Use of the electrical field for reception     30
Use of the magnetic field for reception     30
                  4.2.6     Planning software  31
        4.3     HF band  31
                  4.3.1     Coverage  31
                  4.3.2     Protection ratios  32
                  4.3.3     Propagation  32
                  4.3.4     Frequency choice and coordination  33
                  4.3.5     Reception  35
                  4.3.6     Planning software  35
        4.4     Required S/N ratios for DRM reception  36
        4.5     Minimum usable field-strength values for planning  36
                  4.5.1     Procedure for estimation of the minimum usable field strength  36
                  4.5.2     Computation of minimum usable field strength  36
                  4.5.3     Feedback from field tests  39
        4.6     RF protection ratios  40
                  4.6.1     Relative protection ratios  40
                  4.6.2     Values of relative protection ratios  42
                  4.6.3     RF protection ratios used for HF coordination  47
                  4.6.4     RF power reduction for DRM   49
        4.7     The specific case of the 26 MHz band  50
       4.8      Simulcast 51
       4.9      NVIS  52
       4.10     Example of SFN use in broadcasting below 30 MHz  53
                  4.10.1     System setup  53
                  4.10.2     Stand-alone versus SFN transmitter operation  55
                  4.10.3     Long-term test 56
                  4.10.4     Conclusion  56
 
5     International regulations  56
        5.1     The planning process: assignment planning for LF/MF  56
                  5.1.1     Special study regarding the use of digital modulation in the LF and MF bands governed by the Regional Agreements GE75, RJ81 and RJ88     56
                  5.1.2     Regulatory considerations  57
                  5.1.3     Regional Agreement GE75  57
                  5.1.4     Regional Agreement RJ81  62
                  5.1.5     Regional Agreement RJ88  62
        5.2     Coordination for HF  63
                  5.2.1     The HFBC framework  63
                  5.2.2     The RR Article 12 procedure  63
 
6     Conclusions  63
        6.1     DRM is already operational 63
        6.2     Technical and regulatory information related to DRM services coverage planning that are compiled in this text     64
        6.3     Feedback from operational and experimental transmissions is available  64
        6.4     And next     65
 
7     List of terms (abbreviations) 65
Annex 1  Required S/N values for DRM reception     67
 
1     S/N values for LF/MF bands  67
 
2     S/N values for HF bands  69
Annex 2  Information related to RF protection ratios     72
 
1     Introduction  72
 
2     Calculation parameters  72
        2.1     Analogue signal 72
        2.2     DRM signal 72
        2.3     Values for RF protection ratios  73
Annex 3  Results of some DRM trials     80
 
1     DRM test in the MF band in Madrid  81
 
2     DRM test in the MF band in Mexico City  82
Source: Document WP 6E/403     82
 
3     DRM/AM simulcast tests at MW in Mexico  83
Sources: DRM: MW simulcast tests in Mexico City, Document 6E/403, DRM developments: Experimental and Regular Transmissions     83
 
4     DRM test in the MF band in Italy  85
Source: Document ITU-SG 6/353     85
Global results     85
5      DRM trials in India: simulcast MW, Tropical Band NVIS and 26 MHz local broadcasting  88
Source: Document 6D/10     88
6      Multichannel Simulcast, urban and indoor reception in MW Band  90
Source: Document 6A/73     90
Annex 4  RMS modulation depth     94
Annex 5  DRM facilities and transmissions operated by European Broadcasters     96