This document provides an overview of DVB-NGH, the next generation digital terrestrial TV standard. Some key points:
- DVB-NGH improves upon DVB-T2 with technologies like layered video coding, time-frequency slicing, and support for IP and MPEG2 transport. It also enables MIMO transmission.
- DVB-NGH can be considered a 3rd generation broadcasting system as it allows for MIMO and integration of satellite components for hybrid networks.
- Commercial requirements for DVB-NGH include support for mobile reception up to 350 km/h, 50% improved spectrum efficiency over DVB-H, and combining terrestrial and satellite signals.
- The standard
3. ABSTRACT
DVB-NGH, the handheld evolution of the second-generation
digital terrestrial TV standard DVB-T2.
It uses some new technologies compared DVB-T2.
layered video coding with multiple physical layer pipes.
time-frequency slicing.
full support of an IP transport layer with a dedicated protocol
stack.
header compression mechanisms for both IP and MPEG2 TS
packets.
non-uniform constellations for 64 Quadrature Amplitude
Modulation (QAM) etc
4. DVB-NGH can be regarded the 鍖rst third-generation broadcasting system
because it allows for the possibility of using multiple inputmultiple output
antenna scheme.
DVB-NGH also allows the deployment of an optional satellite component
forming a hybrid terrestrial-satellite network
Continues
5. INTRODUCTION
Emergence of smart phones made Mobile video broadcasting
popular.
Previous technologies are DVB-H and DVB-SH
DVB-NGH is the 鍖rst broadcasting system to incorporate
Multiple-Input Multiple-Output (MIMO) antenna schemes.
physical layer proposals for the next-generation TV
broadcasting technology ATSC 3.0, currently under
evaluation, are based on DVB- T2/NGH
6. MIMO architecture increases the data speed.
DVB systems is the possibility of transmitting DVB-NGH
services in-band within a DVB-T2 multiplex in the same
RF channel
DVB-NGH supports two independent transport protocol
pro鍖les for MPEG-2 TS (Transport Stream) and IP
(Internet Protocol), each one with a dedicated protocol
stack
Continues
7. COMMERCIAL REQUIREMENTS
1. The optimization for outdoor and deep indoor portable and slow
mobile reception, and also for in- vehicle and outdoor vehicular
reception up to 350 km/h.
2. A minimum 50% spectrum ef鍖ciency improvement compared to
DVB-H working under the same conditions.
3. The possibility of combining DVB-NGH and DVB-T2 signals in one
Radio Frequency (RF) channel.
4. The possibility of con鍖guring the system either as a unidirectional
system, or as a bidirectional system with a return channel provided by
a cellular network.
5. The minimization of the overhead such as packet headers and
metadata without losing any functionality
8. 6. The possibility of offering a service in different qualities
with speci鍖c robustness and graceful degradation in fringe
areas of the network.
7. The possibility of transmitting location-based services within
Single Frequency Networks (SFN) with a minimum increase
to network overhead.
8. The possibility of deploying a satellite component as a
complement of the terrestrial network.
Continues
9. Continues
Existence of DVB-NGH frames with DVB-T2 Frame
P-Preamble
FEF-Future extension frame
Frame duration is from 50 ms 200 ms, gives faster zapping time
between the services
10. STANDARDIZATION
STRATEGY
The DVB-NGH speci鍖cation de鍖nes four pro鍖les
1) The base (sheer-terrestrial) pro鍖le.
2) The MIMO terrestrial pro鍖le.
3) The hybrid terrestrial-satellite pro鍖le.
4) The hybrid (terrestrial-satellite) MIMO pro鍖le.
PAPER OVERVIEW
Section II - Describes base profile
Section III - MIMO Terrestrial Profile
Section IV - The hybrid terrestrial-satellite pro鍖le.
Section V - The hybrid (terrestrial-satellite) MIMO
pro鍖le.
Section VI - Conclusion
11. II. Base Profile of DVB-NGH
Introduced in order to improve the
Transmission robustness and increase the spectral efficiency
DVB-NGH has the same restrictions adopted in T2-Lite
aimed to reduce the receiver complexity, such as only the short LDPC
code word size of 16200 bits (16k).
At the constellation level, non-uniform 64QAM and
256QAM constellations and a 4-dimensional rotated QPSK
constellation were introduced.
The I/Q component interleaving replaces the cyclic Q-delay of DVB-T2 to
exploit the signal-space
diversity of rotated constellations
14. Time-Frequency Slicing (TFS)
Transmitting broadcast Services in a several RF channel with
frequency hopping and time-slicing
TFS can provide very important gains both in terms of
capacity due to enhanced (StatMux)
and coverage for both fixed and mobile reception due to
improved frequency diversity [19].
The frequency diversity can significantly improve the
robustness.
Variable Bit Rate and Constant Bitrate Services
18. Physical Layer Signaling
DVB-NGH has enhanced the physical layer signaling of
DVB-T2 in three aspects:
1) Higher signaling capacity.(can add more signaling parameters)
2) Improved transmission robustness.
3) Reduced signaling overhead.
DVB-NGH has increased the capacity
of the signaling preamble and the L1 signaling.
The L1 signaling capacity has been increased because it is not constrained
to the remaining OFDM symbols of the preamble, known as P2
symbol
19. Continues
DVB-NGH also adopted two new mechanisms to improve the
robustness
Incremental Redundancy (IR)
Additional Parity (AP)
Instead of signaling the configuration of each PLP, PLPs are associated
in groups with the same settings, reducing the required signaling
information
20. System and Upper Layers
DVB-NGH supports two independent transport protocol
stacks for TS and IP
21. Continues
The upper layer solution for IP is based on OMA-
BCAST (Open Mobile Alliance Mobile Broadcast
Services Enabler Suite)
MPEG-2 TS Streams
22. Overhead Reduction Methods
TS and IP packet header compression.
The TS packet header is compressed as
follows.
1) The synchronism byte is removed as in DVB-T2.
2) The 1-bit transport priority indicator is removed and
transmitted in the BB frame header.
3) The 13-bit Program ID (PID) field is replaced by a single bit to
signal null packets. The PID value is signaled in
the BB frame header.
4) The 4-bit continuity counter is replaced with a 1-bit
duplication indicator.
24. IP packet header compression
DVBNGH is based on the unidirectional mode of the
Robust Header Compression (ROHC) protocol
NGH adaptation layer was introduced to diminish the
increase in the zapping time and to improve the
robustness of the compressed flow
The adaptation layer is backwards-compatible with
the standalone ROHC Framework.
26. ROHC protocol headers
Inferred
Static
Dynamic
So with ROHC Protocol overhead reduction can be attained.
Continues
27. Local Service Insertion in Single-
Frequency Networks
DVB-NGH adopted two techniques to transmit local content in SFNs, known as
hierarchical and orthogonal local service insertion.
SFN network can be scheduled in a way that different local areas do not
interfere with each other
H-LSI which allows combining two independent data streams into a single
stream with different robustness.
With H-LSI, local services are transmitted in a Low Priority (LP) stream on top
of the global services in a High Priority (HP) stream
29. O-LSI defines groups of OFDM sub-carriers in
specific OFDM symbols for the exclusive use of
particular transmitters to transmit local services
Advantages
the coverage of the global services is not affected by
the local services
coverage of the local services is very similar to the
coverage of the global services.
Continues
30. Enhanced Single-Frequency
Network MISO Scheme
DVB-NGH based on Alamouti coding and a novel
scheme known as eSFN.
The Alamouti code is applied across pairs of
transmitters, eSFN can be applied to multiple
transmitters.
Technology used is eSM+PH
31. MIMO Terrestrial Profile of DVB-NGH
MIMO helps for the capacity increments using
multiple Antenna
The MIMO scheme is known as enhanced spatial
multiplexing with phase hoping (eSM + PH).
33. Hybrid Terrestrial-Satellite Profile of
DVB-NGH
deployment of an optional satellite
component complementing the coverage provided by a
terrestrial network
SC-OFDM demodulation, and a tuner
covering the satellite frequency bands.
Used as an alternate to OFDMA due to its lower Peak to
Average Power Ratio.