Activity of Disseminating Japanese EWBS Technology— Emergency Warning Broadcast System —Yasuji Sakaguchi1

Yasuo Takahashi 2

Seiji Sakuma 3

Digital Broadcasting Experts Group (DiBEG)
Tokyo, Japan
https://www.dibeg.org

Abstract
The Japanese digital terrestria lbroadcasting system (ISDB-T) has
been adopted by 14 countries in Latin
America. DiBEG extends technicalsupport and cooperation to help with
the implementation of ISDB-T in thesecountries. The Emergency WarningBroadcast System (EW BS) is oneof the key features of ISDB-T and is
expected to be introduced as a nationalcommunication system for emergency
situations. The “EWBS Superimpose
Dissemination System”, improved fromthe Japanese original version by meeting
local requirements in Latin America,
has successfully been developed in Japan.
Taking advantage of the robustness of theISDB-T “One-seg” technology, making
maximum use of the existing broadcasting
networks, this system realizes simple
utilization and wide coverage withoutstanding reliability. This system has
already been introduced to some Latin■ Figure 1: Countries adopting ISDB-T (in red)American countries and been evaluatedh igh ly. Japa n cont inues techn ica lcooperation so that EWBS can contributeto disaster prevention and mitigation inthese ISDB-T adopting countries.
1. Technical Requirements for
EWBS in Latin American
Countries
Japan’s Early Warning System, quickly
communicating emergency informationsuch as tsunami and earthquake warnings
to the public, has been introduced mainly
by a mobile communication network andhas long been available on a wide variety ofmobile devices equipped with features suchas area mail and SNS. On the other hand,
although the EWBS using a broadcasting
network has long been in operation by themost broadcasters in Japan, compatible
receivers are limited and not widespreadenough. In that sense EWBS is no morethan a complementary measure in Japan.
In most countries in Latin America,

because the mobile communication
networks have not been well establishedwith enough resilience to sudden line
disconnections, the EW BS throughbroadcasting networks is expected to be acore system for disseminating information
for national disaster prevention. In orderfor EWBS to play this core role, some
improvements were required for it to work
as a more reliable system that will not missan alarm under any conditions. There
are also many differences in broadcasting
operation bet ween Japan and Latin
America. The original Japanese EWBS
version could not be introduced as–is, andlocal requirements in Latin America had tobe satisfied.
The differences in EWBS requirements
are shown in Table 1 on the next page.
2. Development of the “EWBS
Superimpose Dissemination
System”
I n c ol l a b or at ion w it h s e v er a l
manufacturers in Japan and Argentina, wehave developed an “EWBS Superimpose
Dissemination System” to better serve
local requirements in Latin America. Inaddition to the EWBS signals originallyoperated in Japan, this system will alsotransmit character “Superimpose” signal,
which will be received and displayed on
various types of EWBS receivers.
The “Superimpose” function of
ISDB-T transmits text information
independently in the background of thebroadcasting program. This function is
proposed to be used in combination with

1 Yasuji SAKAGUCHI: Director, Broadcasting Systems Engineering, JTEC (Japan Telecommunications Engineering and Consulting Service)
2 Yasuo TAKAHASHIi: Advisor to DiBEG
3 Seiji SAKUMA: Senior Researcher, ISDB-T Promotion Group, ARIB (Association of Radio Industries and Businesses)

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■ Table 1: Differences in requirements for EWBS

■ Figure 2: EWBS Superimpose Dissemination System for Latin
American countries4

EWBS in Latin America for the purposeof communicating disaster information. By
using some control codes of Superimpose,
we also developed a function that canidentify and activate receivers to respondaccording to the type of alarm. We havealso designed several device tests andtraining modes to accommodate various
required operational patterns.
A message signal can be easily inserted
into an existing terrestrial digital network,
and wide coverage and robust transmission
characteristics can be realized easily
and at low cost by using One-segment
signals. This feature enables it to be easily
introduced in Latin American countries
where disaster prevention informationtransmission systems have not beendeveloped well yet.
1)	EWBS Signal Inserter(Transmitting device)
The EWBS Signal Inserter enables
insertion of an EWBS signal, such as
an emergency flag, text Superimpose, orArea-code, into the Broadcast Transport
Stream (BTS) as defined by ISDB-T.
Inserting the EWBS signal at the BTS
stage enables EWBS operation to be
implemented quite easily in the Latin■ Figure 3: EWBS Latin American version – application tovarious operation patterns■ Figure 4: Example of EWBS operation in Peru

American countries adopting ISDB-T,
where various manufacturers have supplied
various ISDB-T broadcasting systems. TheEWBS Signal Inserter can be installedin the master control room at a broadcast
center; or at a local transmitting station toinsert location-specific information intoa TV program. A control terminal (PC)installed at a national organization fordisaster prevention can be connected easily
to the EWBS Signal Inserter throughan IP network. Peru has increased thereliability and security of the entire systemby establishing IP connections through aVPN configuration over a microwave link.
Fig ure 4 shows an example ofoperation in Peru. It ensures that national
and local information can be transmitted ina flexible manner according to its specificpurposes and target areas.
With the cooperation of a local
manufacturer in Argentina, we have also
developed an EWBS signal transmission
system to optimize the DVB distribution
format, which is widely used in Latin
America.
2)	EWBS Reception Module(Reception device)
To promote the sale and permeation ofEWBS receivers in the consumer market,
we have developed a basic module called“EWBS reception module” that can be
deployed in various receivers. This module
constantly monitors the terrestrial digital
One-seg signal of a specific broadcastingstation carrying the EWBS signal, andonce it detects an EWBS signal, it decodes
the signal and outputs an emergency flag
and a text message. In Latin America,
information terminals such as electronicbulletin boards and speakers can be seenaround the city. Mounting this module onthese exiting terminals enables them to be
applied as alarm indicator devices.
■ Figure 5: Wide-ranging applications of theEWBS reception module3) EWBS Signage (Reception device)
We have also developed text display
terminals (EWBS signage) equipped with
the EWBS reception module. These are

4 ISDB-T International Forum: An international group of ISDB-T adopting countries for the purpose of harmonizing the practical application of ISDB-T digital broadcasting

18New Breeze Autumn 2020

intended for installation in public facilities
where people gather, such as government
offices, fire stations and any other disasterprevention locations, as well as in shopping
centers. As a notable installation location,
Peru has installed terminals at radio
stations in local cities and regions. Wheninstalled in a radio booth, if a warning
is received, the radio announcer canread messages to the listeners as they aredisplayed.
The expected application of signage
is for dissemination of information rightafter a disaster (“Post-event information”
in Table 1). An example of application isto install a display in an evacuation center,providing daily lifeline information to theevacuees, such as the status of restoring
lifeline services and volunteer activities.
■ Figure 6: EWBS
signage in operation
at a radio station in Lima, Peru

There are many households in Latin
American countries viewing TV programsby cable, and in such households theinability to receive EWBS signals (byway of digital terrestrial broadcasting) has
been an issue. This STB can switch theHDMI port to show EWBS informationeven while the TV viewer is watching acable TV program. This feature stimulated
and attracted the attention to this STB
product.
In order to check that the CEC
function of the STB is effective and nevermisses an alarm, we performed EWBS
reception trials in Peru and Costa Rica, in
cooperation with a local electronics retailer
in these two countries, using several TV
receivers for sale in stores. The trials
confirmed automatic startup on most of
the TV receivers of major manufacturers,
with only a few exceptions.
This STB can be applied in ordinary
households and also in public places wherea TV is normally installed, such as schoolclassrooms, and hospital waiting areas.
■ Figure 7: Functions

of the EWBS STB4)	EWBS Set-top Box(Reception device)
Since an ordinary STB has only
one tuner, it will receive EWBS signals
while watching a broadcast channel
that is operating the EWBS, but it
will miss alarms while watching otherbroadcast channels. The STB that wehave developed implements a separate,
dedicated tuner that monitors EWBS
24 hours-a-day, so it can receive EWBS
and not miss any EWBS messages. It
also uses the HDMI-CEC function toautomatically start up the TV and it has afunction to switch viewing to the HDMI
port.
HDMI-CEC is a function of HDMI
for Consumer Electronics Control (CEC),
which links operation of electronic
products such as TV receivers and HDD
recorders by exchanging control signals
between them through an HDMI cable.
This STB utilizes the one-touch display
function, which is a common command
function that automatically turns on a TV
if it is switched off and switches the input
to the EWBS channel.

3. Current Status of EWBS
Implementation in Latin
American Countries
The EWBS Superimpose Dissemination
Sy stem has been suppl ied on a nexperimental basis to some of the Latin
American countries adopting ISDB-T.
The current status of technical cooperationfrom Japan and the actual implementationin these countries is described in Table 2
on the next page.
In all of these countries, the equipment
has worked well. Locally in Peru, thesystem was evaluated very highly, and fullscale operation has already started.
We believe that the key to further
system expansion is to improve theoperational level. Each of the countries
was required to start everything from thevery beginning, including expansion ofequipment maintenance, establishing anorganization for system operation, andsecuring government budget for suchpurposes.
Reports with some topics on the latest
implementation status in Costa Rica, Peru
and Brazil are as follows:1)	Costa Rica “One-seg EWBS”
Highly AppreciatedIn March 2019, we performed a
reception evaluation test using actual
radio waves in Costa Rica. We measured
reception in areas with weak field strengthand mobile reception. Costa Rica isa mountainous country. But even inshadow areas where Full-seg cannot bereceived due to topographic conditions,One-seg signals could easily be received
with a simple receiver antenna. For
mobile reception, we conducted reception
tests on traveling trains, vehicles andon boats with a signage receiver. We
were able to verify and show very stable
reception characteristics, which wasgreatly appreciated by local people. We
were able to ensure that One-seg can
be a key element for information andcommunications in the event of a disaster.
In Costa Rica, the feasibility of
the EWBS was conf irmed, and thegovernment is studying the establishmentof a new organization and securing budget
for full-scale EWBS operation.
2)	Peru: Utilization in large scaleevacuation drills on World Tsunami
Awareness DayPeru is the country where EWBS
operation is the most advanced. Peru has
a large land area and a variety of natural
disasters such as wide-area tsunamis on
the coast, heavy rain and landslides in theAndes areas, f looding of the Amazon
River, and cold-weather damage in thehigh mountain areas. It is thus necessary
to desig n a nd implement EW BS
operations in due consideration of thesevarious disasters. It is also important for
the EWBS to establish operational rules
and standardization, including nationwide
and local operations and region code
allocations. As the digital terrestrial
net work expands nationwide in thefuture, the EWBS operation will also
have to develop and expand nationwide.
We have improved the soft ware of

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■ Table 2: Status
of EWBS implementation with support from Japan (in Latin America)

EWBS operations in order to meetthese future requirements in Peru, andthe system has achieved a high level ofoperational performance. We expect thatthe permeation of receivers will naturally
expand as the operational level of EWBSadvances.
On November 5, 2019 commemorating World Tsunami Awareness Day, extensive evacuation drills were conductedin Peru, and EWBS played an importantrole for these drills. A message transmitted
via EWBS was displayed on a large screen
outside the shopping center at the mainvenue. An EWBS signage was also used ina disaster ministerial meeting.
At a symposium the following day,
INDECI, the national organization fordisaster prevention, announced a budget

plan for the adoption and nationwide
deployment of EWBS in Peru.

3)	Brazil: Key country for diffusion ofunified EWBS throughout Latin
America
In Brazil there has been a growinginterest in EWBS recently and they havealready taken their first steps with somefield trials. Brazil is rather different fromother ISDB-T adopting countries in thesense that the EWBS is to be deployed for
all types of critical situation, such as thecollapse of a dam or a nuclear power plant,
and not only for natural disasters.
Brazil was the first country outside
Japan to adopt ISDB-T in 2006. DiBEG
and SBTV D-Forum, the Braziliancounterpart, have long been working
together on implementation of■ Figure 8: Field Survey of EWBS Reception In San Jose,
ISDB-T. We established theCosta Rica (March 2019)“EW BS rapporteur group”
particularly to study unified
EWBS technical standards andoperations throughout Latin
America. In December 2019,
cooperating bet ween Japanand Brazil, we conducted pilot
tests of EWBS in its capital
cit y of Brasilia and could■ Figure 9: EWBS utilized in an event on Worldshow its advantages for many
Tsunami Awareness Day, November 2019stakeholders. The significancein Lima, Peruof Brazil’s adoption of EWBS
is not limited to Brazil. The
transmission and reception
equipment and systems for
ISDB-T digita l terrestria lbroadcasting in Latin America
have been developed andmarketed with close reference
to the Brazilian digital TV

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standards. Broad deployment of EWBS
in Brazil will lead to the spread of EWBS
throughout Latin America, with unified
EWBS operation and equipment.
Conclusion
The EWBS in these Latin Americancountries operates differently than inJapan. For this reason, we have worked
on technical development of an EWBS
Superimpose Dissemination System
to satisfy numerous local requirements.
The system we have developed is being
gradually implemented and verified in
Peru and other Latin American countries
adopting ISDB-T, and we are continuing
technical support and cooperation forstable and reliable system operation.
We are confident that collaboration
between Japan and Latin Americancountries will standardize and unify themost suitable systems in the near future,and that devices will be launched anddeveloped in the market, leading to broad
adoption of EWBS and contributing todisaster prevention and mitigation.
Acknowledgments
We would like to express great
appreciation to the Ministry of Internal
Affairs and Communication of Japan for
its exceptional support for our activities.
We would also like to thank several
manufact urers that have prov ided
us w ith technica l suppor t for thedevelopment of EWBS devices. Thesea re TA NA BIK I Inc., CEN T U RY
C O R P O R AT I O N , N O R I TA K E
I T R O N C O R P O R AT I O N a n d
MASPRO DENKOH CORP. from Japanas well as VideoSwitch from Argentina.
We also thank Mr. Cesar Gallegos,
from Peru, and Mr. Frank Coloma, fromCosta Rica, who have been working as
local coordinators for these activities.
We are grateful to the SBTVD-Forumin Brazil, for cooperative study as well as
many others in Latin American countries
adopting ISDB-T, who have generously
extended understanding and cooperation
to us in these activities