Digital Radio Mondiale

Digital Radio Mondiale Before its Trade Launch in June 2003 Andy Giefer BBC World Service

Overview DRM Recording & Editing Distribution Transmission Monitoring Do-it-yourself DRM

At a Glance Digital Radio System for LF, MF, HF Improved Audio Quality Better Usability

Timeline 1998 Consortium founded 2000 Field trials start 2001 ITU recommendation & ETSI standard 2003 IEC Standard 2003 Launch at WRC in June 2004 First consumer receivers 2005/2006 Mass-market cheap receivers

What have we learned?

II: Recording & Editing

Recording often uses compression Minidisk, MP3 recorder Non-linear editing often uses compression Minimise effects of cascaded audio coding Use low compression, e.g. 384 kbit/s

III: Distribution

Encoding and mutliplexing Where should the programme be encoded? Sat Studio TX Site

Encoding and mutliplexing At the Studio? Sat Studio TX Site DRM Mux

Encoding and mutliplexing Or at the Transmission Site? Sat Studio TX Site DRM Mux

At Studio Output Use Multiplex Distribution Interface (MDI) Includes audio and modulator information 32-48 kbit/s per stream One stream per modulator setting

At Transmission Site Cascaded coding requires low compression Codec MPEG layer-2 MPEG layer-3 MPEG-4 AAC aacplus Mono Bitrates 96...128 kbit/s 64...96 kbit/s 48...64 kbit/s 32...48 kbit/s

Which method? Central factors Modulator settings used at Tx sites Determines satellite capacity Feed used for other delivery systems? Synchronised networks used?

IV: Transmission

Modulator Settings Pure DRM or DRM in simulcast HF bandwidths: 4.5, 9, 10, 18 and 20 khz Robustness modes A, B, C, D 6 code rate/constellation combinations

Modulator Settings Pure DRM or DRM in simulcast HF bandwidths: 4.5, 9, 10, 18 and 20 khz Robustness modes A, B, C, D 6 code rate/constellation combinations

SSB DRM 9/10 khz

AM DRM 13.5/15 khz

AM DRM 18/20 khz

DRM 18/20 khz

Modulator Settings Pure DRM or DRM in simulcast HF bandwidths: 4.5, 9, 10, 18 and 20 khz Robustness modes A, B, C, D 6 code rate/constellation combinations

Mode A B C D Robustness Application Medium-wave Short-wave Doppler HF Tropical HF

Modulator Settings Pure DRM or DRM in simulcast HF bandwidths: 4.5, 9, 10, 18 and 20 khz Robustness modes A, B, C, D 6 code rate/constellation combinations

64-QAM 16-QAM 0.78 0.71 0.6 0.5 0.62 0.5 B/10k 27 25 21 17 15 12 A/9k 31 28 24 20 16 13 A/20k 72 65 55 46 38 31 Bit rates in kb/s

64-QAM 16-QAM 0.78 0.71 0.6 0.5 0.62 0.5 B/10k 27 25 21 17 15 12 A/9k 31 28 24 20 16 13 A/20k 72 65 55 46 38 31 AAC or CELP Mono

64-QAM 16-QAM 0.78 0.71 0.6 0.5 0.62 0.5 B/10k 27 25 21 17 15 12 A/9k 31 28 24 20 16 13 A/20k 72 65 55 46 38 31 aacplus Mono AAC or CELP Mono

64-QAM 16-QAM 0.78 0.71 0.6 0.5 0.62 0.5 B/10k 27 25 21 17 15 12 A/9k 31 28 24 20 16 13 A/20k 72 65 55 46 38 31 aacplus Pseudo Stereo aacplus Mono AAC or CELP Mono

64-QAM 16-QAM 0.78 0.71 0.6 0.5 0.62 0.5 B/10k 27 25 21 17 15 12 A/9k 31 28 24 20 16 13 A/20k 72 65 55 46 38 31 aacplus Stereo aacplus Pseudo Stereo aacplus Mono AAC or CELP Mono

Networks Single-Frequency-Networks Reduce risk of flat fading Multiple-Frequency-Networks Use frequency diversity Receivers switch frequency automatically Increase signal reliability!

V: Monitoring

Automatic monitoring possible (unlike AM) Estimate Signal strength Signal-to-Noise Ratio Doppler & delay spread Audio quality: %-age correct audio frames Try to reduce information for overviews Feedback to set modulator dynamically?

16 Monitoring receivers in Europe Send daily email data files Central database sends daily text summaries Started in April 2002

Daily Report ------------------------------------------------------------------------------------------------------ 14:00-15:00 2003-03-26 Mode:B MSC:64 SDC:4 Prot:A0/B1 20880 bps 5875 khz "BBCWorld Service ------------------------------------------------------------------------------------------------------ RxName Quality[%] AudioQ>0%: MER AudioQ=100%: MER Signal [dbuv] Delay90[ms] Doppler[Hz] Slot Audio 10% [db] 10% Med 90% [db] 10% Med 90% 10% Med 90% 10% Med 90% BBC1 100.0 100.0 25 25 29 31 30 38 46 0.5 0.8 2.5 0.3 0.4 1.0 BBC3 100.0 100.0 22 22 27 29 71 80 90 0.1 0.2 2.4 0.2 0.4 0.9 DW1 99.8 99.8 25 25 28 30 47 61 74 0.1 0.3 3.8 0.2 0.3 0.6 NOR5 9.0 14.2 7 13 22 31 0.3 2.4 3.9 0.3 0.5 1.0 RNW3 99.8 99.8 16 18 27 29 41 53 59 0.1 0.4 2.3 0.2 0.4 0.9 ULM1 100.0 100.0 22 22 27 30 41 46 56 0.4 1.4 3.1 0.3 0.5 1.0 Evolution of Audio Quality Q in 1-Minute Steps. L is the accumulated dropout length in seconds. 0%<=Q<10%: _ 10%<=Q<90%: - Q=100%: ` 5<L<=6: 5 4<L<=5: 4 3<L<=4: 3 2<L<=3: 2 1<L<=2: 1 0<L<1: * BBC1 BBC3 DW1 NOR5 RNW3 ULM1 ````````````````````````````````````````````````````````` ````````````````````````````````````````````````````````` ````````````````````````````````````1```````*11*`*```1**` - ---- --_-_--_--- --- ****````*````*``****`````***```````*```*``*`**`******`*`` `*``*``````````````````````````````````````````````````*`

Daily Report ------------------------------------------------------------------------------------------------------ 14:00-15:00 2003-03-26 Mode:B MSC:64 SDC:4 Prot:A0/B1 20880 bps 5875 khz "BBCWorld Service ------------------------------------------------------------------------------------------------------ RxName Quality[%] AudioQ>0%: MER AudioQ=100%: MER Signal [dbuv] Delay90[ms] Doppler[Hz] Slot Audio 10% [db] 10% Med 90% [db] 10% Med 90% 10% Med 90% 10% Med 90% BBC1 100.0 100.0 25 25 29 31 30 38 46 0.5 0.8 2.5 0.3 0.4 1.0 BBC3 100.0 100.0 22 22 27 29 71 80 90 0.1 0.2 2.4 0.2 0.4 0.9 DW1 99.8 99.8 25 25 28 30 47 61 74 0.1 0.3 3.8 0.2 0.3 0.6 NOR5 9.0 14.2 7 13 22 31 0.3 2.4 3.9 0.3 0.5 1.0 RNW3 99.8 99.8 16 18 27 29 41 53 59 0.1 0.4 2.3 0.2 0.4 0.9 ULM1 100.0 100.0 22 22 27 30 41 46 56 0.4 1.4 3.1 0.3 0.5 1.0 Evolution of Audio Quality Q in 1-Minute Steps. L is the accumulated dropout length in seconds. 0%<=Q<10%: _ 10%<=Q<90%: - Q=100%: ` 5<L<=6: 5 4<L<=5: 4 3<L<=4: 3 2<L<=3: 2 1<L<=2: 1 0<L<1: * BBC1 BBC3 DW1 NOR5 RNW3 ULM1 ````````````````````````````````````````````````````````` ````````````````````````````````````````````````````````` ````````````````````````````````````1```````*11*`*```1**` - ---- --_-_--_--- --- ****````*````*``****`````***```````*```*``*`**`******`*`` `*``*``````````````````````````````````````````````````*`

64-QAM 16-QAM 0.78 0.71 0.6 0.5 0.62 0.5 B/10k 27 25 21 17 15 12 A/9k 31 28 24 20 16 13 A/20k 72 65 55 46 38 31 aacplus Mono AAC or CELP Mono

Daily Report ------------------------------------------------------------------------------------------------------ 14:00-15:00 2003-03-26 Mode:B MSC:64 SDC:4 Prot:A0/B1 20880 bps 5875 khz "BBCWorld Service ------------------------------------------------------------------------------------------------------ RxName Quality[%] AudioQ>0%: MER AudioQ=100%: MER Signal [dbuv] Delay90[ms] Doppler[Hz] Slot Audio 10% [db] 10% Med 90% [db] 10% Med 90% 10% Med 90% 10% Med 90% BBC1 100.0 100.0 25 25 29 31 30 38 46 0.5 0.8 2.5 0.3 0.4 1.0 BBC3 100.0 100.0 22 22 27 29 71 80 90 0.1 0.2 2.4 0.2 0.4 0.9 DW1 99.8 99.8 25 25 28 30 47 61 74 0.1 0.3 3.8 0.2 0.3 0.6 NOR5 9.0 14.2 7 13 22 31 0.3 2.4 3.9 0.3 0.5 1.0 RNW3 99.8 99.8 16 18 27 29 41 53 59 0.1 0.4 2.3 0.2 0.4 0.9 ULM1 100.0 100.0 22 22 27 30 41 46 56 0.4 1.4 3.1 0.3 0.5 1.0 Evolution of Audio Quality Q in 1-Minute Steps. L is the accumulated dropout length in seconds. 0%<=Q<10%: _ 10%<=Q<90%: - Q=100%: ` 5<L<=6: 5 4<L<=5: 4 3<L<=4: 3 2<L<=3: 2 1<L<=2: 1 0<L<1: * BBC1 BBC3 DW1 NOR5 RNW3 ULM1 ````````````````````````````````````````````````````````` ````````````````````````````````````````````````````````` ````````````````````````````````````1```````*11*`*```1**` - ---- --_-_--_--- --- ****````*````*``****`````***```````*```*``*`**`******`*`` `*``*``````````````````````````````````````````````````*`

Daily Report ------------------------------------------------------------------------------------------------------ 14:00-15:00 2003-03-26 Mode:B MSC:64 SDC:4 Prot:A0/B1 20880 bps 5875 khz "BBCWorld Service ------------------------------------------------------------------------------------------------------ RxName Quality[%] AudioQ>0%: MER AudioQ=100%: MER Signal [dbuv] Delay90[ms] Doppler[Hz] Slot Audio 10% [db] 10% Med 90% [db] 10% Med 90% 10% Med 90% 10% Med 90% BBC1 100.0 100.0 25 25 29 31 30 38 46 0.5 0.8 2.5 0.3 0.4 1.0 BBC3 100.0 100.0 22 22 27 29 71 80 90 0.1 0.2 2.4 0.2 0.4 0.9 DW1 99.8 99.8 25 25 28 30 47 61 74 0.1 0.3 3.8 0.2 0.3 0.6 BBC1 100.0 NOR5 9.0 14.2 7 13 22 31 0.3 2.4 3.9 0.3 0.5 1.0 RNW3 99.8 99.8 16 18 27 29 41 53 59 0.1 0.4 2.3 0.2 0.4 0.9 ULM1 100.0 100.0 22 BBC3 22 27 30 100.0 41 46 56 0.4 1.4 3.1 0.3 0.5 1.0 Evolution of Audio Quality Q in 1-Minute Steps. L is the accumulated dropout length in seconds. 0%<=Q<10%: _ 10%<=Q<90%: - Q=100%: ` 5<L<=6: 5 4<L<=5: 4 3<L<=4: 3 2<L<=3: 2 1<L<=2: 1 0<L<1: * BBC1 BBC3 DW1 NOR5 RNW3 ULM1 RxName DW1 99.8 NOR5 9.0 RNW3 99.8 ````````````````````````````````````````````````````````` ````````````````````````````````````````````````````````` ````````````````````````````````````1```````*11*`*```1**` - ---- --_-_--_--- --- ULM1 100.0 ****````*````*``****`````***```````*```*``*`**`******`*`` `*``*``````````````````````````````````````````````````*` Quality[%] Slot

Daily Report ------------------------------------------------------------------------------------------------------ 14:00-15:00 2003-03-26 Mode:B MSC:64 SDC:4 Prot:A0/B1 20880 bps 5875 khz "BBCWorld Service ------------------------------------------------------------------------------------------------------ RxName Quality[%] AudioQ>0%: MER AudioQ=100%: MER Signal [dbuv] Delay90[ms] Doppler[Hz] Slot Audio 10% [db] 10% Med 90% [db] 10% Med 90% 10% Med 90% 10% Med 90% BBC1 100.0 100.0 25 25 29 31 30 38 46 0.5 0.8 2.5 0.3 0.4 1.0 BBC3 100.0 100.0 22 22 27 29 71 80 90 0.1 0.2 2.4 0.2 0.4 0.9 DW1 99.8 99.8 25 25 28 30 47 61 74 0.1 0.3 3.8 0.2 0.3 0.6 NOR5 9.0 14.2 7 13 22 31 0.3 2.4 3.9 0.3 0.5 1.0 RNW3 99.8 99.8 16 18 27 29 41 53 59 0.1 0.4 2.3 0.2 0.4 0.9 ULM1 100.0 100.0 22 22 27 30 41 46 56 0.4 1.4 3.1 0.3 0.5 1.0 Evolution of Audio Quality Q in 1-Minute Steps. L is the accumulated dropout length in seconds. 0%<=Q<10%: _ 10%<=Q<90%: - Q=100%: ` 5<L<=6: 5 4<L<=5: 4 3<L<=4: 3 2<L<=3: 2 1<L<=2: 1 0<L<1: * BBC1 BBC3 DW1 NOR5 RNW3 ULM1 ````````````````````````````````````````````````````````` ````````````````````````````````````````````````````````` ````````````````````````````````````1```````*11*`*```1**` - ---- --_-_--_--- --- ****````*````*``****`````***```````*```*``*`**`******`*`` `*``*``````````````````````````````````````````````````*`

Daily Report ------------------------------------------------------------------------------------------------------ 14:00-15:00 2003-03-26 Mode:B MSC:64 SDC:4 Prot:A0/B1 20880 bps 5875 khz "BBCWorld Service ------------------------------------------------------------------------------------------------------ RxName Quality[%] AudioQ>0%: MER AudioQ=100%: MER Signal [dbuv] Delay90[ms] Doppler[Hz] Slot Audio 10% [db] 10% Med 90% [db] 10% Med 90% 10% Med 90% 10% Med 90% BBC1 BBC3 ````````````````````````````````````````````````````````` ````````````````````````````````````````````````````````` BBC1 100.0 100.0 25 25 29 31 30 38 46 0.5 0.8 2.5 0.3 0.4 1.0 BBC3 DW1 100.0 ````````````````````````````````````1```````*11*`*```1**` 100.0 22 22 27 29 71 80 90 0.1 0.2 2.4 0.2 0.4 0.9 DW1 99.8 99.8 25 25 28 30 47 61 74 0.1 0.3 3.8 0.2 0.3 0.6 NOR5 9.0 - ---- --_-_--_--- --- 14.2 7 13 22 31 0.3 2.4 3.9 0.3 0.5 1.0 99.8 99.8 16 18 27 29 41 53 59 0.1 0.4 2.3 0.2 0.4 0.9 RNW3 ****````*````*``****`````***```````*```*``*`**`******`*`` ULM1 100.0 100.0 22 22 27 30 41 46 56 0.4 1.4 3.1 0.3 0.5 1.0 ULM1 `*``*``````````````````````````````````````````````````*` Evolution of Audio Quality Q in 1-Minute Steps. L is the accumulated dropout length in seconds. 0%<=Q<10%: _ 10%<=Q<90%: - Q=100%: ` 5<L<=6: 5 4<L<=5: 4 3<L<=4: 3 2<L<=3: 2 1<L<=2: 1 0<L<1: * BBC1 BBC3 DW1 NOR5 RNW3 ULM1 ````````````````````````````````````````````````````````` ````````````````````````````````````````````````````````` ````````````````````````````````````1```````*11*`*```1**` - ---- --_-_--_--- --- ****````*````*``****`````***```````*```*``*`**`******`*`` `*``*``````````````````````````````````````````````````*`

VI: Do-it-yourself DRM

Software Receivers Open-source DRM receiver TU Darmstadt Official DRM Software Radio http://www.drmrx.org Build your own receiver http://www.etsi.org

Use HAM radio receivers!

Record data and give feedback

Schedule on http://www.drm.org http://www.rnw.nl

VII: Summary

Recording & Editing Use low compression: 384 kb/s Distribution Encode at Studio or at Tx Site Central multiplexer for SFN/MFN Transmission Simulcast, Mod. settings

Monitoring Automatic processing of a wealth of data Possible feedback to modulator Do-it-yourself DRM Downlaod software receiver Build your own DRM system

http://www.drm.org

The End