Asia R&D, Home Entertainment & Sound

Asia R&D, HESRDM

Saddam Mustafa, Digital Field Expert responsible for Africa & Middle East.

• Based in Dubai• Saddam.Mustafa@ap.sony.com

Stephen Cleary, Digital Broadcast Specialist responsible for Africa & Middle East.

• Based in Kuala Lumpur, Malaysia• Stephen.Cleary@ap.sony.com

Asia R&D, HESRDM

• LCD – Logical Channel Descriptor

• LCN – Logical Channel Number

• PDS – Private Data Specifier

• ONID – Original Network ID

• NIT – Network Information Table

• SDT – Service Descriptor Table

• DVB – Digital Video Broadcasting

• DTT – Digital Terrestrial Television

Asia R&D, HESRDM

• The Scope of this Presentation is

– Explain the background to logical channel numbers.

– How LCNs are defined within the ECOWAS Draft Specification

– How Cross Border Conflicts can be resolved

– Next Steps for Regulators

Asia R&D, HESRDM

Logical channel numbers (LCN) allow the broadcaster to control where each specific service is positioned in the service list.

In the absence of LCNs, Manufacturers can order services in their own specific way. E.g.

• Lowest Frequency first, SDT first

• Alphabetical ordering

Asia R&D, HESRDM

Current tuned Mux

2nd Loop of NIT

LCDv1 Tag

Current Mux

LCD are found in the 2nd Loop of the NITactual.

During Linear Scan, typically, the LCD is processed for current tuned Mux only.

Descriptor_tag 0x83 is ‘typically’ used for LCDv1.

Descriptor_tag 0x87 is ‘typically’ used for LCDv2.

Asia R&D, HESRDM

Syntax No. of bitslogical_channel_descriptor(){

descriptor_tagdescriptor_lengthfor (i=0;i<number_of_services;i++){

service_idvisible_service_flagreservedlogical_channel_number

}}

88

161510

LCDv1 (E-Book) tag 0x83Syntax No. of bitslogical_channel_descriptor(){

descriptor_tagdescriptor_lengthfor (i=0;i<number_of_services;i++){

service_idvisible_service_flagreservedlogical_channel_number

}}

88

161114

LCDv1 (Nordig) tag 0x83

Syntax No. of bitslogical_channel_descriptor(){

descriptor_tagdescriptor_lengthfor (i=0;i<number_of_services;i++){

service_idreservedlogical_channel_number

}}

88

16610

LCDv1 (UK DTG) tag 0x83• Tag 0x83 not assigned by DVB

• By Convention tag 0x83 is used to indicate LCDv1

• Different variants of LCDv1!!

Asia R&D, HESRDM

• Descriptor_tag >= 0x80 is not defined by DVB.

• PDS preceding tag 0x83 used to decide which variant.

NZ PDS implies E-Book LCN

ITC PDS implies

DTG UK LCD

If no PDS, then apply

country spec, or best guess.

No invisibility Flag

Asia R&D, HESRDM

Invisible flag; Service is only

accessible using the numeric

keys ‘6’, ‘0’, ‘0’

LCNs can include the concept of Invisible services,

Invisible services do not appear in service list or in EPG.

Invisible services are not accessible via Prog+ / Prog-.

Invisible services Only accessible by numeric keys.

Asia R&D, HESRDM

LCDv2 provides the option of multiple orderings depending on user preferences.

Syntax No. of bits Identifier

Logical_channel_descriptor(){descriptor_tagdescriptor_lengthfor (i=0;i<N;i++){channel_list_idchannel_list_name_lengthfor (i=0;i<N;i++) {

char}country_codedescriptor_lengthfor (i=0;i<number_of_services;i++){

service_idvisible_service_flagreserved_future_uselogical_channel_number

}}

}

8 8

8 8

8

24 8

16 1 510

UimsbfUimsbf

UimsbfUimsbf

Uimsbf

UimsbfUimsbf

UimsbfBslbfBslbf

Uimsbf

Asia R&D, HESRDM

If only one list found, then UI is not displayed.

At end of auto-tuning user must choose between different channel list names.

Asia R&D, HESRDM

If two or more services request the same LCN, then only one can be allocated the LCN.

Typically Service with Higher Signal Quality/Strength is assigned the requested LCN.

LCN1 -

Red

LCN1 -

Green

LCN1 - GreenLCN1- Red

Asia R&D, HESRDM

Original Network ID (per country) is assigned by DVB

In DTT used to indicate country of origin of signal. E.g.

• Ghana ONID is 0x2120

• Singapore ONID is Ox22BE

If User selects Ghana during Autostartup, then services with ONID 0x2120 are given priority.

Services with other ONIDs are placed in the overflow area.

Asia R&D, HESRDM

• If Receiver is able to install service from multiple countries and no ONID defined.

Receiver not be able to tell the country of origin

The service list of the two countries may be mixed.

LCN1LCN1

LCN1LCN1

Ghana ONID = 0x2120

Côte d’Ivoire

No ONID yet Border

Asia R&D, HESRDM

Valid Range for ECOWAS is 1 to 799.

.

Main Area

Overflow Area

LCN Range 1-799

Services Assigned as per

Logical Channel

Descriptor.

Will contain all types of

services including

Radio/Data/Video

LCN Range 800-999

Services inserted based

rules outlined here.

In-country invalid LCN

Foreign Services

Duplicate Services

LCN = 999

Different

ONID

Losing LCN 1

LCN 1

If LCN requested outside Valid Range, then the service is placed in the overflow area. E.g. No LCN, LCN =0, LCN = 999

.

Asia R&D, HESRDM

In Country Services

Foreign Services

1 ~ N

Sequentially ordered

N+1 ~

Sequentially ordered

If no LCNs are detected during scanning for any service, then services are ordered from position 1.

Manufacture is allowed decide sequential order.

Different

ONID

Asia R&D, HESRDM

Main Area

Overflow Area

LCN Range 1-799

Services Assigned as per

Logical Channel

Descriptor.

Will contain all types of

services including

Radio/Data/Video

LCN Range 800-999

Services inserted based

rules outlined here.

In-country invalid LCN

Foreign Services

Duplicate Services

Asia R&D, HESRDM

Asia R&D, HESRDM

Asia R&D, HESRDM

• LCNs Strictly controlled by the Regulator– Lower LCN has positive commercial implications

– E.g. France, UK

• LCNs are explicitly not allowed– Too Contentious if not controlled from the start

– E.g. Spain (Some pirate channels do broadcast LCN)

• LCNs are allowed, but uncontrolled– Complete Chaos and user confusion after ASO

– E.g. Italy after ASO, 15+ channels requesting LCN1 in Milan

Max User

Confusion

Max

Regulation

Asia R&D, HESRDM

- Regulator needs to request ONID from DVB- ONID can be requested via the following web page

http://www.dvbservices.com/identifiers/original_network_id

- Broadcasters need to use the assigned ONID.

- Manufacturer needs to implement the Country Setting in Auto-startup- This could be mandated or optional in specification.

Asia R&D, HESRDM

Asia R&D, HESRDMAsia R&D, Sony TV Group

Asia R&D, HESRDM

HD Simulcast Descriptor

Target Region Descriptor

Transmission of LCNv1 and LCNv2 at the same time

Further Reading Materialhttp://www.nordig.org/pdf/NorDig-Unified_ver_2.4.pdf