Digital Radio in MW, LW and SW

DRM30- DRM30 -

The economic solution for large areaThe economic solution for large area coverage

Jean-Francois KippSenior sales engineer AM and DRM transmittersAM and DRM transmitters

Jochen HuberCEO TRANSRADIO andCEO TRANSRADIO andVice president of the DRM Consortium

1. DRM - The Standard

DRM : One standard for all bands

• DRM30 : perfect for large coverage areas in LW, MW, SW (< 30 MHz)

• DRM+ : perfect for urban coverage p g(>30 MHz)

O St d d O S l ti f ll d d fi ti• One Standard, One Solution for all needs and configurations

2. DRM30 – Digital Radio g

b fit i AM B dbenefits in AM Bands

Benefits of Digital AM for BroadcastersReduced power consumption of transmitters 40%• Reduced power consumption of transmitters ~40%

• Increased covering areas• Increased possible number of listeners• Faster return of investment• Easy operation of SFN/MFN

Comparison of reception distance AM vs DRM30 :

DRM : minimal usable field strength (dBuV/m) to get a BER of 1x10exp(-4) (ITU)

Modulation Protection Level No.Minimal usable field strength

(dBuV/m)0 33 1

16 QAM0 33,11 35,20 38,6

64 QAM

1 39,82 41,63 43,2

Necessary field strength for DRM reception: min. usable field strength + 7 dB (statistic variation of field strength) + 3 dB reserve

Comparison of reception distance AM vs DRM30 :

Necessary Field Strength Coverage Distance

Coverage Distance as a function of necessary field strength for DRM reception:

Strength

[dBuV/m] DRM-Mode Parameter

Coverage Distance

(100 kW Transmitter)

43 1Mode A, 16QAM,

Coderate 0 5 41743.1 Coderate 0,5 417

48.6Mode A, 64QAM,

Coderate 0,5 366Mode A, 64QAM,

49.8, Q ,

Coderate 0,6 345

53.2Mode A 64QAM,

Coderate 0,78 309

Comparison of reception distance AM vs DRM30 :Example of New Delhi : G d d ti it t i l f I diGround conductivity : typical for IndiaTransmission Frequency : 666kHz Transmitter power : 100 kW

AM DRMNecessary field strengthfor reception

60dBuV/m 43dBuV/mfor receptionCoverage distance 245 km 417 km

Transmitted Power 106 kW 63,7 kW (using Digital Power E h t f DRM DMOD3 d(m=0,35) Enhancement of DRM DMOD3 and Transradio TRAM Transmitters

Power Comsumption 122 kW(m=0 35)

73,3 kW(m 0,35)

Comparison of reception distance AM vs DRM30 :

Benefits for the Broadcasters :Benefits for the Broadcasters :Benefits for the Broadcasters :Benefits for the Broadcasters :

You save : 48,7 kW

You win : 172 km coverage in Radius

357.700 km² more coverage in DRM than in AM with the same transmitter

(based on TRANSRADIO MW Transmitter and DRM Modulator)

Benefits for the Broadcasters :Benefits for the Broadcasters :Benefits for the Broadcasters :Benefits for the Broadcasters :

• Larger covered area with less power consumption

• Usage of DRM multicontent advantage -> Up to 4 speech channels

3. DRM30 solutions

in AM Bands

Field proven DRM30 Systems

TRAM TX1GPS-antenna or external clock RFdrive

DRM DMOD3Optional FraunhoferDRM ContentServerTM R4

Parallelingunit

AntennaMDIdata

ENV1

RFout

Antenna

RFRFback(directionalcoupler)

data

ENV2

OptionalFraunhofer DRM Monitoring Receiver

TRAM TX2

Audio

RFdriveRFout DT 700

RFback

Design of a modern DRM30 Exciter

• pure modular Soft- and Hardware design• Linux based

High reliability and stable platform• Low power consumption

High end DDS RF section• High end DDS RF section• Wide temperature range

up to 45°C• Ergonomic high resolution

touch screen display

DRM DMOD3, Main featuresMain features

• MCS on two 9 (10) kHz channels• Fast and easy switchover between modes in less than 5 seconds!• Integrated GPS receiver for single frequency networks (SFN) and

highest frequency precision• Feed back channel for optimization of the transmission system• Feed back channel for optimization of the transmission system• Integrated synthesizer, Frequency range 9kHz to 27 MHz

• All purpose solution : Perfect suitable for LW, MW and SW

DRM DMOD3, Parameter settingsDC OffsetDC Offset

-10

0

10error [%]

Color

0 Blue

0.2 Black

-40

-30

-20

tral D

ensi

ty [d

B/H

z]

0.2 Black

0.7 Magenta

1.0 Brown

2.0 Orange

80

-70

-60

-50

Pow

er S

pect

5.0 Grey

-100 -80 -60 -40 -20 0 20 40 60 80 100-90

-80

Frequency [kHz]

• Operating the transmitter with the correct DC‐offset is crucial.p g

• DC‐offset error < 1 % to fulfill the DRM mask.  

DRM DMOD3, Parameter settingsTime DelayTime Delay

0

10error [µs]

Color

0 Blue

0.25 Green

-30

-20

-10

Den

sity

[dB

/Hz] 1 Black

2 Cyan

5 Magenta

-60

-50

-40

Pow

er S

pect

ral

-80 -60 -40 -20 0 20 40 60 80-80

-70

Frequency [kHz]

Time Delay between envelope & RF path  < 1 µs to fulfill the DRM mask

DRM DMOD3, Parameter settingsBand Limitation of Envelope PathBand Limitation of Envelope Path

0

10Cut-Off-Frequency (3dB) in kHz

Color

20 Green

-30

-20

-10

Den

sity

[dB

/Hz] 30 Black

35 Magenta

40 Gray

-60

-50

-40

Pow

er S

pect

ral

No filter Blue

DRM RF Bandwidth: 10kHz

-60 -40 -20 0 20 40 60-80

-70

Frequency [kHz]

At least 3.5 times the RF bandwidth necessary for DRM to fulfill DRM mask

DRM DMOD3, Parameter settingsAutomatic Equalizer Adjustment IAutomatic Equalizer Adjustment I

Phasemodulated

Phi

Equalizer

DRM DMOD3

MDI Decoder&

OFDM Generator

I-Qto

A-PhiConversion

TX

EnvelopeFilter

MDI

+Upsampling

&RF-Output

DelayAdjustment

I,Q

DC-OffsetFilter Coefficients

A-PhiDelay

RF

Envelope

Phi

A

DRM DMOD3Auto - Adjust Test

Point 1

CoefficientsDelay

RF-Input&

Downsampling

Measuring Pointswitching device

TestPoint 2

TestPoint 3

DRM DMOD3, Parameter settingsAutomatic Equalizer Adjustment IIAutomatic Equalizer Adjustment II

DRM DMOD3, Parameter settings, using Digital Power EnhancementThe Result TRAM 50 with 41,5KW DRM power

4. DRM30 Antenna Problematic

DRM in PracticeSmall bandwidth

Antenna, typical in LF Band

DRM Exciter TX

• DRM spectrum not compliantwith ITU spectrum maskM k i l ti t 15dB!• Mask violation up to 15dB!

Minimum requirements for DRM AntennasMinimum requirements for DRM Antennas

VSWR < 1,05 at ± 5 kHz from carrier

VSWR < 1,10 at ± 10 kHz from carrier

What to do if my antenna doesn’t meet these specifications ?specifications ?

• Change the antenna system, which could last 20 years more ?

-> non economical solution

P t ENW i th t i i li• Put an ENW in the transmission line

-> cost effective

DRM in practice; here on MW and LW

ENW Heusweiler 1422 kHz ENW Summerhill 252 kHz

DRM in Practice; here on Longwave

ENW(extended network)

DRM Exciter TX

• DRM spectrum compliantwith ITU spectrum mask!

• Equalizer settings calculated with DRM signal onlyDRM signal only

Donebach, Germany, 153kHz, 500kW

Donebach, Germany, 153kHz, 500kW

• Recording was done 100 km awayfrom the Donebach stationfrom the Donebach station during acceptance test

• Receiver reaches a SNR higherece e eac es a S g ethan 30.4dB (31dB SNR was measured atTX output)

• Excellent transmission qualityfor DRM on Long Wave

5. TRANSRADIO DRM Reference

Site in LF and MF Bands

Cremlingen, Germany in 2005

Transmitter StationCremlingen (TSI)GermanyGermany

BroadcasterDeutschlandRadio

Transmissionfrequency 756 kHz

Output Power 800/400 kW

Bandwidth 9 kHz

800 kW TRANSRADIO TRAM line solid state transmitter TRAM/P800 756kHz

Zehlendorf, Germany in 2006

Transmitter Station Zehlendorf (TSI)

Broadcaster DeutschlandRadioBroadcaster DeutschlandRadio

Transmissionfrequency 177kHz

Output Power 500/240kWOutput Power 500/240kW

Bandwidth 9kHz

Transmitter TRAM/P500L

TRANSRADIO DRM Transmitter TRAM/P 500L

Zehlendorf, Germany in 2006Worlds first DRM transmitter on• Worlds first DRM transmitter on long wave, which completely met the requirements of the out-of-band emissions of ETSI EN 302 245-1 and ITU SM.1541

Mainflingen

Burg

Kalundborg, DK

Burg, Mainflingen and Kalundborg are signals received from other stations

Summerhill, Ireland in 2007

Transmitter StationSummerhill (RTENL)

Broadcaster RTE

Transmission frequency 252kHzq y

Output Power 300/160kW

Bandwidth 9kHz

Transmitter TRANSRADIO TRAM 300 L

Aholming, Germany in 2008

Transmitter StationAholming (TSI)GermanyGermany

BroadcasterDeutschlandRadio

Transmissionfrequency 207 kHz

Output Power 500/240 kW

Bandwidth 9 kHz

500 kW TRANSRADIO TRAM line solid state transmitter TRAM/P 500L 207kHz

Donebach, Germany in 2008

Transmitter StationDonebach (TSI)GermanyGermany

BroadcasterDeutschlandRadio

Transmissionfrequency 153 kHz

Output Power 500/240 kW

Bandwidth 9 kHz

500 kW TRANSRADIO TRAM line solid state transmitter TRAM/P 500L 153 kHz

Heusweiler, Germany in 2008

Transmitter StationHeusweiler (SR)GermanyGermany

BroadcasterDeutschlandRadio

Transmissionfrequency 1422 kHz

Output Power 400/200 kW

Bandwidth 9 kHz

400 kW TRANSRADIO TRAM line solid state transmitter TRAM/P 400 1422 kHz

Thank you for Thank you for your attentionyour attention