DVB-T2 First Deployments, First Experiences.

Transcription

1 Levira's 5th Digital Broadcasting Conference "Fresh Connections" DVB-T2 First Deployments, First Experiences. DVB-T2 Lite trials in Copenhagen for mobile-tv and digital radio. As one of the first in Europe, Open Channel started trials of the next generation digital terrestrial TV standard - DVB-T2 in Open Channel again leads the way, airing the next generation of mobile-tv and digital radio, based on the new standard DVB-T2 Lite in Kenneth Wenzel, Director Page1

2 Content What does Open Channel do? DVB-T2 standard and what is a T2-Lite profile? The second chance for broadcast mobile-tv The future standard of digital radio Your questions are welcome Page2

3 What does Open Channel do? Page3

4 Independent Danish DTT operator Since 2006 performing tests and operating terrestrial digital television in Copenhagen Currently broadcasting 3 different DTT mux in Copenhagen, signals can be received by more than 700,000 households, representing 28% of all Danish households - MUXCPH (UHF ch. 35) is focused on deployment of HbbTV and HEVC - MUXCPH-2 (UHF ch. 39) is focused on the future mobile-tv format, T2 Lite, which is the successor of DVB-H - MUXCPH-3 (VHF ch. 9D) is focused on the future format of digital radio, T2 Lite, as an alternative to DAB/DAB+ on a socalled T-DAB channel (1.7 MHz BW) Page4

5 Technology and Broadcast partner Danish ProTelevision Technologies (modulator) Spanish Broad Telecom SA (transmitter) Norwegian Nevion (formerly T-Vips, T2 Gateway) Swedish Exir Broadcasting (output filters) Dutch DekTec (DVB-T2 test equipment) Russian Elecard (HEVC software encoding & decoding) French HTTV (HbbTV head-end) as well as France Medias Monde (France 24) and Channel Copenhagen (Kanal København) plus a number of idtv manufacturers like Sony, Samsung, Phillips, Bang & Olufsen and Chinese settop box manufacturer Trimax Page5

6 DVB-T2 standard and what is a T2-Lite profile? Page6

7 DVB-T2 Improved robustness The commercial focus on DVB-T2 was originally mainly on stationary reception, but DVB-T2 is also designed to work well in mobile/handheld conditions DVB-T does not include time interleaving and is therefore sensitive to impulsive interference and time varying channels DVB-T2 has support for deep time interleaving and longer symbol period, which together radically improves the robustness against impulsive interference Page7

8 DVB-T2 Advantages with multiple PLPs Possibility to reach different kinds of receivers and reception conditions with a single RF signal HDTV to roof-top directional antennas in PLPs with normal robustness PLPs Mobile receivers with robust PLPs Possibility to prioritize robustness for selected highpriority services -> prioritized services (e.g. public service) will last longer in bad reception conditions Statistical multiplexing over several PLPs is possible PLPs may be sent in a bursty way -> allows for power saving in mobile devices ( time slicing ) Page8

9 DVB-T2 New Bandwidths DVB-T2 has three additional bandwidth options compared to DVB-T DVB-T DVB-T2 Frequency bands 1.7 MHz (same as DAB) VHF band III and L-band 5 MHz 3x1.7 MHz in L-band 6 MHz 6 MHz e.g. Colombia 7 MHz 7 MHz typically VHF band III 8 MHz 8 MHz typically UHF band IV/V 10 MHz for non-consumer use Page9

10 T2 Lite New DVB-T2 profile T2-Lite is a light version of DVB-T2 that allows for implementation of mobile devices with low complexity and low power consumption T2-Lite is mainly a subset of the main DVB-T2 standard (T2- Base), except two new code rates for robustness (1/3, 2/5), and where components with high complexity are removed. DVB-T2 (T2 Base) T2-Lite Each PLP bit rate limited to 4 Mbit/s Page10

11 T2 Lite Future Extension Frames A mechanism that allows a future system to be sent as Future Extension frames in T2 time slots Allows flexible capacity allocation to fixed and mobile services by adjusting the size of T2 frame and FEF Page11

12 RAI starts T2 Lite trials with FEF Page12

13 T2 Lite Stand-alone T2-Base-Lite, the perfect DVB-T2 profile for mobile-tv and digital radio DVB-T2 (T2 Base) T2- Base- Lite T2-Lite L1 pre-signaling "T2_BASE_LITE" is really interesting. A mode in which this bit is set to 1 will therefore be suitable for reception by both T2-base-only and T2-lite-only receivers. Page13

14 The second chance for broadcast mobile-tv On Air since March 2012 with T2-Base-Lite for mobile-tv Page14

15 Background DVB-H was never a success Very few DVB-H receivers in the market No demand for watching TV on a tiny cell phone screen (QVGA, 320 x 240) - and certainly not if you had to pay for it Page15

16 Tablets will open new opportunities Now, with the increasing popularity of ipads and other tablets, the demand for linear TV viewing on smaller screens has arrived The challenge with the new tablets and smartphones are that they have a screen size of 1080p or 2048x1536 as the new ipad The bandwidth necessary for unicast mobile TV can be a challenge for mobile operators - especially during major sporting events. Here, T2-Lite provides an efficient new platform for broadcasting mobile-tv Page16

17 MUXCPH-2 UHF channel 39 (618 MHz) TDC radio tower in the center of Copenhagen Transmit power: 2 kw ERP omni-directional Antenna Height: 104 meter Polarization: Vertical T2-Base-Lite profile (DVB-T2 version 1.3.1) 64 QAM 16K-ext GI 19/256 CR 1/2 PP3 6 PLP each with its own TV channels Net bitrate Mbit/s Page17

18 Broadcast Page18

19 In car DVB-T2 set top box Few DVB-T2 "in car" STB on the market -> they are in fact just ordinary stationary 12 volts DVB-T2 STB s Reason for this is that the new mobile DVB-T2 chip from Siano and DIBCOM (now Parrot) has not yet been release. Expected Q Page19

20 HEVC aka H.265 HEVC makes it possible to broadcast television channels in HD in 720p or 1080p with a capacity of less than 4 Mbit/s, allowing broadcast with T2 Lite standard for tablet and smartphone Page20

21 The future standard of digital radio T2-Base-Lite for digital radio On Air since June 2012 DVB-T2 Lite is not only suitable for mobile TV. It is also highly suitable as the future standard of digital radio instead of DAB (1995) & DAB+ (2007) Page21

22 Capacity of DAB / DAB+ D-QPSK GI = 1/4 (246 µs) Corresponding max. direct TX distance (SFN): 73.8 km Urban (TU12) channel model Netto Mbit/s C/N AWGN C/N Rayleigh Time varying Number of radio CR 1/2 DAB GE06 (15 km/h) 1,152 7,4 db 14,0 db ~ 6 DAB Mode 1, PL 3 1,152 *7,6 db **13,5 db ~ 6 DAB+ Mode PL 3A*** 1,056 5,7 db 11,8 db ~ 16 Results from simulations and laboratory measurements are given, together with values for the noise figure of DAB receivers The required C/N for mobile reception was measured to be 13.5 db Page22

23 Capacity of DVB-T2 Lite at 1.7 MHz BW FFT size = 4K GI 1/8 (277.5 µs) LDCP 16K Corresponding max. direct TX distance (SFN): 83.2 km (DAB: 73.8 km) T2-Base-Lite 16QAM Netto Mbit/s C/N AWGN C/N Rayleigh Static C/N Rayleigh Time varying* Number of radio CR 1/2 PP2 2,067 6,1 db 7,7 db 8,7 db ~ 32 PP3 2,160 6,2 db 7,8 db 9,7 db ~ 33 CR 3/5 PP2 2,798 7,8 db 9,5 db 10,5 db ~ 43 PP3 2,913 7,9 db 9,6 db 10,6 db ~ 45 CR 2/3 PP2 3,117 9,0 db 10,9 db 11,9 db ~ 48 PP3 3,245 9,1 db 11,0 db 12,0 db ~ 50 Corresponding receiver's speed limits (rough estimation!): 203 km/h *C/N Rayleigh Time varying = C/N Rayleigh Static + 1,0 db Page23

24 Comparison between T2-Lite and DAB/DAB+ With DVB-T2 you get 3.3 Mbit/s capacity (~ 50 radio) compared to the DAB / DAB+ 1,1 Mbit/s capacity (~ 6 / ~ 16 radio) with the same propagation model. If you just want to transmit 1,1 Mbit/s (~ 16 radio) would the broadcasting strength could be reduces 8 times (~ 9 db) with an equivalent reduction of the transmission costs. T2-Base-Lite FFT size = 4K GI 1/8 (277.5 µs) LDCP 16K Corresponding max. direct TX distance (SFN): 83.2 km (DAB: 73.8 km) QPSK Netto C/N C/N Rayleigh C/N Rayleigh Mbit/s AWGN Static Time varying* CR ½ PP3 1,069 1,3 db 2,3 db 3,3 db ~ 16 Number of radio Page24

25 1.7 MHz channel raster Many manufacturers continue to use outdated DVB-T1 silicon tuners However this should no longer be an issue since e.g. following silicon tuner supports 1.7 MHz channel raster: -Sony Semiconductor CXD2861 & NXP NDA18274 & NDA Broadcom BCM3461 NIM & BCM7563 SoC -Silicon Labs Si21x8 & Si21x7 -Rafael Microelectronics R828S 1.7 MHz raster within VHF band III is mandatory e.g. for the Irish Digital Terrestrial Television IRD (Saorview) Page25

26 MUXCPH-3 VHF channel 9D (208,064 MHz) TDC radio tower in the center of Copenhagen Transmit power: 520 W ERP; Dipol antenna Antenna Height: 100 meter Polarization: Vertical T2-Base-Lite profile (DVB-T2 version 1.3.1) 16QAM 4K GI 1/8 CR 2/3 PP3 Net bitrate Mbit/s Page26

27 Trimax DVB-T2 STB with 1.7 MHz BW Page27

28 Signal reception quality: 208,064 MHz Page28

29 Thank you! Your questions are welcome Page29

30 DAB / DAB+ *Source: Ofcom, DAB Coverage Planning 2310/DAB/R/1.2, 17th June 2011, Pages 43. And ETSI TR reproduces (as figure 1) the same plot22 for Mode I performance given in BS.1114 which shows a value of 7.6 db for BER=10-4. ** Source: EBU Tech3317 July 2007: p13 & P33: Measurements of the required C/N for T-DAB have been made at the IRT (Institut für Rundfunktechnik) for both mobile and portable reception using a Typical Urban (TU12) channel model. The required C/N for mobile reception was measured to be 13.5 db. *** Source: EBU BPN 101, May 2012, Report on Frequency and Network Planning Parameters related to DAB+. Pages 6 a Gaussian type channel was assumed for fixed reception, whereas for mobile and portable reception a Rayleigh channel (profile TU12 at 25 km/h and 178 MHz) was assumed. Page30