LOCAL RADIO BROADCASTING IN 26 MHz

1. LOCAL RADIO BROADCASTING IN 26 MHz Sharad Sadhu Asia-Pacific Broadcasting Union ITU-ABU WORKSHOP: DIGITAL RADIO IMPLEMENTATION FOR DEVELOPING BROADCASTERS 3-6 August, 2009, Malaysia

2. WHY LOCAL BROADCASTING IN 26 MHz ?

3. 26 MHz BAND IS FOR LONG DISTANCE SERVICES • 25670- 26100 kHz • Long distance transmissions through ionospheric propagation • Rarely used • With “line-of-sight” propagation: • Can be used for local digital radio, like FM • Part of band may be kept for international services

4. 26 MHz LOCAL RADIO FEATURES • 25670- 26100 kHz • With “line-of-sight” propagation: • Can be used for local digital radio, like FM • Part of band may be kept for international services

5. NEW DELHI 26 MHz TRIAL • May 2007 • Partners: • ABU, All India Radio • DRM, Thomson, Ikegami, Univ of Basque • 60 participants from several countries • Transmitter conversion • Workshop • Test transmissions • Field Measurements in Delhi – New Delhi city

6. NEW DELHI 26 MHz TRIAL Field measurements • Analysis of signal behavior in urban areas in static, mobile conditions • Comparison of measured results with existing prediction models

7. NEW DELHI 26 MHz TRIAL Transmission system

8. NEW DELHI 26 MHz TRIAL Transmission set up

9. NEW DELHI 26 MHz TRIAL Transmission parameters

10. NEW DELHI 26 MHz TRIAL Measurement parameters • fixed reception at 2 locations • mobile reception along 6 routes through the city • All routes measured between 4.5 and 7 km from the transmitter.

11. NEW DELHI 26 MHz TRIAL • Measurement results • Objective audio quality is 100 % • SNR is much higher than 10 dB (ITU-R Rec BS 1615) • Field strength threshold (SNR value) is much higher than 37 dBµV/m obtained in tests elsewhere

12. NEW DELHI 26 MHz TRIAL • Mobile test results

13. NEW DELHI 26 MHz TRIAL • Mobile test results • Good results - Route 1 • 6.3 km to 5.1 km from transmitter • Field strength is higher • Audio dropouts when SNR is below 12 dB

14. NEW DELHI 26 MHz TRIAL • Mobile test results • Route 6 is from 5.9 to 6.1 km from transmitter. Many audio dropouts on this route • Field strength is just higher than 40 dBµV/m all along. SNR below 12 dB shows coverage failures

15. NEW DELHI 26 MHz TRIAL • Conclusions • Static measurements at two locations • Received SNR well above threshold at both locations • Excellent reception along the route up to 7 km towards downtown • When entering city centre with high buildings, high power noise sources were encountered along with signal strength dropouts • Reception was very good in city centre except for the high building areas • DRM audio quality was very good • This technology has shown to have great potential and should be further analyzed with a view for implementation

16. NEW DELHI 26 MHz TRIAL • Conclusions • B/16/4/.5/S in 26 MHz with 500 W Tx power provides stable signal, good quality audio in Delhi and New Delhi with Yagi antenna

17. A Word About ABU Dedicated to Members’ Needs • 210 members in 59 countries • Development of broadcasting • Activities of common interest • Pursues broadcasting issues internationally

18. THANK YOUFOR YOUR ATTENTION