International Journal

on Marine Navigation

and Safety of Sea Transportation

Volume 6

Number 3

September 2012

323

1 INTRODUCTION

Paper describes Integrated Vessel Traffic Control

System realizing fusion of data received from shore

based station of the Automatic Identification System

(AIS) and pulse and Frequency Modulated Continu-

ous Wave (FMCW) radars and presenting infor-

mation on Electronic Navigational Chart issued by

the Polish National Hydrographical Service – Hy-

drographical Office of the Polish Navy. Additionally

on the Observation Post is installed Multi Camera

System consisting of daylight and thermal cameras

showing automatically object tracked by radar and

selected manually by operator.

System was designed and built in the scope of re-

search work financed by the Polish Ministry of Sci-

ence and Higher Education as developmental project

No OR00002606 from the means for science in

2008-2010 years.

2 MODEL OF INTEGRATED VESSEL TRAFFIC

CONTROL SYSTEM

2.1 System configuration and features

Model of Integrated Vessel Traffic Control System

has a modular architecture. This system has been

subdivided into autonomous modules. Each of them

can be individually maintained, upgraded and/or re-

placed. Presented system has been designed to make

possible development of his elements and functions

in the future. The structure of the system has been

shown in Figure 1.

Figure 1. Scheme of Integrated Vessel Traffic Control System.

The Integrated Vessel Traffic Control System is

an open-ended system, which is possible to integrate

with external systems. The system consists of one

Observation Post and one Control Centre. If re-

quired, there are abilities to connect to Control Cen-

Integrated Vessel Traffic Control System

M. Kwiatkowski, J. Popik & W. Buszka

Telecommunication Research Institute Ltd., Gdańsk, Poland

R. Wawruch

Gdynia Maritime University, Gdynia, Poland

ABSTRACT: Paper describes Integrated Vessel Traffic Control System realizing fusion of data received from

the shore based station of the Automatic Identification System (AIS) and pulse and Frequency Modulated

Continuous Wave (FMCW) radars and presenting information on Electronic Navigational Chart. Additionally

on the Observation Post is installed Multi Camera System consisting of daylight and thermal cameras show-

ing automatically object tracked by radar and selected manually by operator.

324

tre several Observation Posts. All elements of the

system are linked through the LAN (Local Area

Network).

Figure 2 shows functional diagram of Observa-

tion Post. It consists of the following devices:

− Pulse radar in X band;

− Frequency Modulated Continues Wave (FMCW)

radar in X band;

− Multi cameras system which comprise of daylight

and thermal cameras; and

− Class A station of the Automatic Identification

System (AIS).

The pulse radar as well as the FMCW radar includes

plot extractor and tracker device.

The pulse NSC 25/34 Raytheon radar has been

applied in the model of integrated system for the

performance tests. This radar is characterized by the

maximum range equal 24 Nm. However the CRM-

203 FMCW radar, also used in the Observation Post,

has been produced by Telecommunication Research

Institute Ltd. This radar is able to detect objects at

maximum distance equal 48 Nm. It is necessary to

remember that range of radar destined to detection

of sea surface objects, also depends on a height of

antenna location and propagation conditions of elec-

tromagnetic wave.

Figure 2. Functional diagram of the Observation Post.

CRM-203 is fully solid state radar. It makes use

of modern technologies such as generation of emit-

ting signals on the base of frequency Direct Digital

Synthesis (DDS) and Fast Fourier Transform (FFT)

processing implemented in signal processors Ti-

gerSHARC and Field Programmable Gate Array

(FPGA) circuits VIRTEX. Described radar can de-

tect sea surface targets and determine movement pa-

rameters of objects. It is equipped with modules re-

alizing ARPA's functions and can cooperate like

pulse ship’s radars with external sources of infor-

mation (GPS receiver, ship speed measuring device,

gyrocompass, satellite compass, scanner of charts,

etc.). CRM-203 is able to automatically tracking of

detected targets and to pass information about

tracked objects to command and control systems.

More detailed information about utilised FMCW

radar was presented during the previous TransNav

conference (Plata 2009).

Multi cameras system Sargas KDT-360 has been

installed on Observation Post of integrated system.

KDT-360 has been manufactured by the Polish

company Etronika. Maximum range of the multi

cameras system is in the order of several kilometers.

If necessary, it is possible to apply in the integrated

system cameras, which have better range features.

Moreover for performance tests purposes in Inte-

grated Vessel Traffic Control System has been used

as AIS coastal station AIS class A device produced

by SAAB.

The main task performed by the Observation Post

is supply information about sea surface situation in

detection range of the radars and operation range of

the AIS system. Moreover, remote controlled multi

cameras system can make identification of objects

detected by remain sensor or even external systems.

All devices are able to work in the unattended mode.

The functional diagram of the Control Centre has

been presented in Figure 3. The centre consists of

equipment as follows:

− Server;

− Operator workstation; and

− Printer.

Server as well as operator workstation operate under

control of Red Hat Enterprise Linux 5 operating sys-

tem.

Figure 3. Functional diagram of the Control Centre.

The Dell Power Edge T610 server has been used

in the presented system. This computer has two four

cores and 64 bits processors Xeon X5570, 32 GB of

RAM as well as five 300 GB hard disks. Hard disks

are operating under matrix system RAID 6.

325

The Dell Precision T5500 computer has been ap-

plied as operator workstation. This machine has

64 bits processor Intel Xeon W5580, 12 GB of

RAM, two 300 GB capacity hard disks and graphical

card NVIDIA Quadro FX3800. Hard disks in the

workstation are operating under matrix system

RAID 1.

The Control Centre performs tasks as follows:

1 Generalization of information about current sea

surface situation. The process relies on verifica-

tion and data association collected from sensors,

which operate on Observation Post.

2 Monitoring, collecting and updating of sea sur-

face information within the scope of:

− Tracking of all sea surface targets in range of

Control Centre operation;

− Identification and classification of detected ob-

ject;

− Distinguishing between stationary and mova-

ble objects;

− Assertion of vessel entrance to areas temporar-

ily or permanently prohibited and other areas

defined by the operator;

− Assertion of vessel descent from in forcing

maritime routes; and

− Cooperation with others services.

3 Archiving and play back of recorded sea surface

situation.

Information received from radars and AIS are put

to the database. Next, these data are subjected to fu-

sion. Results of fusion are also written down to the

base. Communication and control of the sensors, the

database and the data fusion algorithms have been

implemented in the server.

Data from the base and the sensors i.e. radars,

AIS and even multi cameras system can be trans-

ferred automatically (in suitable range) to external

systems. Information from these external systems

can be received automatically, as well. Received da-

ta, such as targets tracks from radars and AIS are

written down to the base and are subject to fusion

with information obtained from local sensors of In-

tegrated Vessel Traffic Control System.

Information from all local sensors and external

systems are presented on two computer displays.

Actual positions and movement vectors of targets,

detected by radars and received from AIS devices

installed on vessels, are presented in the graphical

form on Electronic Chart Display and Information

System (ECDIS) (Weintrit 2009). The picture from

multi cameras system is presented in the separate

window (daylight or thermal camera). Archived

comprehensive sea surface situation can be playing

back in any moment.

Presented configuration of the model of integrat-

ed system and its functions can be changed. There-

fore, modifications and development of manufac-

tured vessel traffic control system are possible in

dependence on needs and requirements of a custom-

er.

2.2 Data fusion

Multi-sensor data fusion is one of the most effective

ways to solve problems of different groups, which

have common characteristic features. It uses data

from multiple sources to achieve a result which

would not be possible to obtain from a single sensor.

Data received from different sources can be associ-

ated by make use of specific procedures of signal

processing, recognition, artificial intelligence and in-

formation theory. Many methods of data fusion have

been developed and their common feature is an in-

clusion of multiple layers of data processing in the

integration process.

Fusion process used in presented system can be

divided into several main stages (Figure 4):

1 Unification of state vectors units of targets and

bringing them to single timeline.

2 Association.

3 Determination of an updated state vectors.

The need to harmonize the time, results from the

asynchronous operation of sensors. They operate

with different frequencies and can be turned on at

different times. For example the position of radar an-

tennas working in the system can be different at any

given time. Uniform period of time equal 1 second

has been adopted. It allows easy synchronization of

data received from sensors with different frequen-

cies (typically: 2, 3, 6, 10 seconds).

Association is performed using the modified

PDAF algorithm (Probabilistic Data Association Fil-

ter) (Bar-Shalom et al. 1995, Bar-Shalom et al.

2001, Krenc 2006). In the modification we assume

that there are two (or more) sources of varying quali-

ty. The associated measurement can come from two

sources, one or none. Additionally, there is one vali-

dation gate, inside of which are measurements from

both sources. The modification relay on adding new

innovation vectors v and association mass e of these

vectors:

⋅+⋅

⋅

−

⋅⋅−

5.0

(1)

where: v - the innovation vector; e - association mass

of innovation vector; S - innovation matrix; and

i, j - indexes (i ≠ j).

In this way has been assumed that data are re-

ceived from both sensors and probability of such

hypothesis is calculated. This allows several percent

of improvement in the quality of estimation.

326

Figure 4. Diagram of data fusion process.

The state vector updates are assigned on the basis

of calculated innovation vectors and association

probabilities.

The algorithm allows for flexible operation, de-

pending on currant conditions (adaptive assessment

of interferences) and quantity of information

sources.

2.3 Sea surface situation picture

As mentioned in paragraph 2.1, the function of

presentation of sea surface situation has been im-

plemented in the operator workstation. Picture is

presented on two displays, which shows fully inde-

pendent graphic information from the radars, AIS,

multi cameras system and external systems. Posi-

tions and motion vectors are displayed with different

accuracy, depending on the type of objects:

− Detected only by radars;

− Transmitting AIS data and not detected by radars;

− Detected by radars and transmitting AIS data, af-

ter data fusion.

Sea surface objects are presented on electronic

navigation chart (Weintrit 2009). The situation can

be displayed on full screen of two monitors simulta-

neously or one monitor or else in dedicated window.

It is also possible to observe magnified area in sepa-

rate window. Operator’s console is presented in Fig-

ure 5. An example of costal sea surface situation pic-

ture is shown in Figure 6, whereas an example of

data fusion working is presented in Figure 7.

Figure 5. Operator’s console.

Figure 6. An example of costal sea surface situation picture.

On the left monitor there is the window display-

ing moving objects on the background of navigation

chart. Above, on top of the screen, has been placed

Menu Bar which make possible to choose the sub-

menu for selection of actions or to open control win-

dows. At the bottom of the screen has been placed

Status Bar (see Figure 6).

The right monitor is designed generally to present

windows with tables that contain descriptions of tar-

gets obtained from all sensors or external systems,

additional descriptions of tracking objects and tar-

gets after data fusion as well as to present the picture

from multi cameras system. An operator can shapes

the view on the screen in suitable for him manner

because any windows can be moved in the frame of

main window.

Figure 7. Two detected and tracked targets (circle 1 – FMCW

radar, circle 2 – pulse radar, triangle – AIS, point – data fu-

sion).

Software package EC2007 ECDIS Kernel devel-

oped by SevenCs GmbH has been used to build nav-

igation charts background. The package allows the

application of various types and formats of electron-

ic digital charts supplied by different manufacturers.

327

The set of tools and libraries Qt developed by

Nokia (formerly Trolltech) has been used to build

controls elements of the picture and specialized win-

dows, which present e.g. the list of sea surface pa-

rameters or the picture obtained from multi cameras

system. Qt provides up-to-date components and

mechanisms to build operator interface and tools to

implement communication, processing of text doc-

uments or to use databases.

The use of both software tools, i.e. EC2007 EC-

DIS Kernel and Qt, allows to rapid implementation

of the software which meet the requirements of

IHO/IMO.

Some parts of the operator interface functions

have been performed solely for research purposes,

such as fusion algorithms and can not be found in

the target Integrated Vessel Traffic Control System.

Similarly, the units implemented in control parame-

ters of multi cameras system are as required by this

device. It has been done in order to facilitate opera-

tion tests and control of used multi cameras system.

Units or scope of unit’s description should be

adapted to thinking ways and working procedures of

an operator.

The solution of the picture displayed on monitors,

which has been adopted in Vessel Traffic Control

System, is flexible. Depending on the operator's

needs, presentation of sea surface situation and other

necessary information can be freely shaped.

3 CONCLUSIONS

Paper presents Integrated Vessel Traffic Control

System designed and constructed in the scope of re-

search work mentioned in the introduction. The sys-

tem works and results of its performance tests con-

ducted in autumn and winter 2010 are described in

other paper presented on this conference.

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Bar-Shalom Y., Rong Li X., Kirubarajan T. 2001. Estimation

with Applications to Tracking and Navigation. John Wiley

& Sons Inc.

Krenc K. 2006. Statistic methods of processed data evaluation

for the purpose of information fusion in C&C systems.

MAST.

Plata S., Wawruch R. 2009. CRM-203 Type Frequency Modu-

lated Continuous Wave (FM CW) Radar. TransNav - Inter-

national Journal on Marine Navigation and Safety of Sea

Transportation, Vol. 3, No. 3, pp. 311-314

Weintrit A. 2009. The Electronic Chart Display and Infor-

mation System (ECDIS). An Operational Handbook. CRC

Press, Taylor & Francis Group