Abstract—Mobile position-aware systems combined with

modern wireless technologies are getting more and more

important and everyone seems to realize that the market is a high

potential industry. For mobile network it is a way to differentiate

many mobile applications and services from PC (Personal

Computer) applications and wired Internet services. Using mobile

devices, LBSs (Location-Based Service) leverage a user’s physical

location to provide enhanced services and experiences. LBSs

enable a range of applications and services, such as navigation

and mobile map services, workforce tracking, finding points of

interest, and obtaining weather information. Nowadays most of

the applications are based on the GPS (Global Positioning

System). However, the availability of indoor location, which is not

covered by satellite-based systems, and fast time to position fix is

more and more needed for LBSs. This fact opens the door to

UWB (Ultra Wide band) as a key technology to be taken into

account in the development of novel and promising location-

aware services, due to its intrinsic features for providing accurate

indoor localization. Indoor location provided by UWB combined

with cellular networks such as HSPA (High Speed Packet Access)

or WiMAX (Worldwide Interoperability for Microwave Access)

will open the door to a large set of new location-aware services.

Index Terms—coexistence, HSPA, location-awareness, UWB,

WiMAX

I. INTRODUCTION

user is accessing the Internet from his smartphone thanks to a WiMAX or HSPA connection. The user goes in a

shopping centre that is equipped with a LDR-LT UWB (Low Data Rate-Location and Tracking Ultra Wide Band) technology, which allows monitoring, localization and tracking. The user downloads the map on his smartphone thanks to the WiMAX/HSPA link. Then he is able to select

Manuscript received December 1, 2009. The work presented in this paper

has been carried out within the European research project EUWB which is partly funded by the Commission of the European Union under the 7th European Framework Programme for Research and Technological Development (FP7) and here under the Information and Communication Technologies (ICT) research programme.

P. Cluzeaud and I. Bucaille are with Thales Communications, 146 boulevard de Valmy, 92700 Colombes (France) (e-mail: pierre.cluzeaud@fr.thalesgroup.com, isabelle.bucaille@fr.thalesgroup.com).

A. Sierra is with Telefónica I+D, Emilio Vargas 6, 28043, Madrid (Spain) (e-mail: asd@tid.es).

J. Chóliz is with Institute of Engineering Research in Aragón, I3A, University of Zaragoza, C\ María de Luna, 3, 50018, Zaragoza (Spain) (e-mail: jcholiz@unizar.es).

any shop just by clicking on it. The LDR-LT UWB technology will give him the shortest way to get there. This scenario could represent a usual situation these days. This paper will give an overview of these services and their requirements for an operator. Then we will detail the multi-radio devices needed for this application, which are under development in the EUWB project. Finally, the demonstration platforms, where these multi-interface user terminals will be integrated, will be described.

II. NEW LOCATION-AWARE SERVICES

A. New user services

UWB localization [1] systems could be deployed in a variety of scenarios in order to provide users with dual cellular/UWB devices [2], [3] with precise positioning information even in indoor environment thanks to UWB technology. This would allow the user to position himself on his device in the same way as car navigation systems and locate the place he wants to go. But location information could also be forwarded to the access network operator, which would allow the development of location-aware services. Therefore, the users could get information of interest (special offers in shopping malls, arrival times in stations and airports, match statistics in sports stadiums, etc.) both through the UWB network and through the access network. There exist a broad range of different location-based

services. The Fig. 1 gives an overview on the main categories of LBS applications.

Fig. 1. LBS application categories

UWB in Heterogeneous Access Networks: location-aware services

P. Cluzeaud, I. Bucaille, A. Sierra, J. Chóliz

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978-1-4244-7157-7/10/$26.00 ©2010 IEEE 257

• Emergency services: one of the most evident applications of LBS is the ability to locate an individual who is either unaware of his exact location or is not able to reveal it because of an emergency situation (injury, criminal attack, and so on). With the exact location even in indoor environment automatically transferred to the emergency services the assistance can be provided quickly and efficiently.

• Navigation services: based on mobile users needs for directions within their current geographical location. The ability of a mobile network to locate the exact position of a mobile user can be manifested in a series of navigation-based services. By positioning a mobile phone, an operator can let the user know exactly where he is as well as give him detailed directions about how to get to a desired destination.

• Information services: finding the nearest service, accessing traffic news, getting help when navigating in an unfamiliar city, obtaining a local street map – these are just a few of the many location-based services.

• Tracking and management services: it can be equally applicable both to the consumer and the corporate markets. One popular example refers to tracking postal packages so that companies know where their goods are at any time. Vehicle tracking can also be applied to locating and dispatching an ambulance that is nearest to a given call. A similar application allows companies to locate their field personnel (for example, sales people and repair engineers) so that they are able, for example, to dispatch the nearest engineer and provide their customers with accurate personnel arrival times. Finally, the new found opportunity to provide accurate product tracking within the supply chain offers new possibilities to mobile supply chain management.

• Billing services: it refers to the ability of a mobile location service provider to dynamically charge users of a particular service depending on their location when using or accessing the service.

B. New operator services

Besides the development of location-aware services, the location information provided by UWB can also be used by the operators in order to enhance their networks, for example, aiding network planning. The operator may be able to locate calls in certain areas to estimate the distribution of calls and user mobility for network planning purposes. These applications may be utilized for hot spot detection and user behaviour modelling. Moreover, focusing on the QoS of the network, the UWB positioning system may be employed to track dropped calls to identify problematic and poor quality areas. Finally, the location information can be used by the operator to improve Radio Resource Management, with more intelligent handovers and more efficient channel allocation techniques based on localization prediction.

III. REQUIREMENTS OF ADVANCED SERVICE PLATFORMS

A. Components of location- based services

The basic components needed to use a location-based service are illustrated in Fig. 2 [4].

Fig. 2. Components of LBS and their connections

• Mobile Devices: a tool for the user to request the needed information. The results can be given by speech, using pictures, text and so on. Possible devices are PDAs, mobile phones, laptops... but the device can also be a navigation unit of a car or a toll box for road pricing in a truck.

• Communication Network: the second component is the mobile network which transfers the user data and service request from the mobile terminal to the service provider and then the requested information back to the user.

• Positioning Component: for the processing of a service usually the user position has to be determined. The user position can be obtained either by using the mobile communication network or by using specific positioning systems such as the GPS and UWB. The former is widely used for outdoor navigation systems, whereas the latter can especially be used for indoor navigation.

• Service and Application Provider: the service provider offers a number of different services to the user and is responsible for the service request processing. Such services offer the calculation of the position, finding a route, searching yellow pages with respect to position or searching specific information on objects of user interest and so forth.

• Data and Content Provider: service providers will usually not store and maintain all the information which can be requested by users. Therefore a geographic data and location information data base will be usually requested from the maintaining authority (e.g. mapping agencies) or business and industry partners (e.g. yellow pages, traffic companies).

EUWB project is focusing on the combination of UWB and access network. Two advanced multi-radio platforms are studied in the scope of the project in order to provide new location-aware services. A first platform is composed of a UWB LDR (Low Data

Rate) device and a HSPA device. Some interesting scenarios

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for this application are shopping malls, train stations, airports, exhibition centres, sports stadiums, hospitals, museums etc. A second platform is composed of a UWB LDR device and

a WiMAX device. The application will be more focused on public safety for which an interesting scenario is the firefighter scenario. UWB technology will allow provisioning firefighter precise localization in indoor environment, what is very useful during emergency situations.

B. Use cases of UWB location-based services

Within the wide variety of location-based services applications, several use cases have been identified that may benefit of the localization capabilities of UWB technology. • Indoor navigation The objective of this service is to provide users with a navigation tool similar to car navigation systems but aimed to indoor environments. At this point UWB arises as a very good alternative to provide this positioning information in indoor environments, due to its high accuracy, low cost and power consumption and good performance in multipath and even NLOS (Non Light of Sight) conditions.

• Location-based search The objective of this service is to provide users with customized search results ordered according to user’s location. This can be useful for requesting the nearest business or service, such as an ATM or restaurant.

• Proximity marketing The objective of this service is to provide users with information such as latest bargains, special offers, discounts coupons, etc. of the shops and business nearby. The advertisements could be targeted only to certain users according to characteristics such as age, user profile, etc.

• Children surveillance The objective of this service is to support parents when visiting amusement parks, shopping centres, multiscreen movie complexes, museums, family entertainment centres, etc. With this purpose, children would wear a wristband with an integrated LDR-LT UWB transceiver and parents would get a notification (SMS) when children move apart from them.

• Buddy-finder The objective of this service is to notify users about the proximity of other service users that are linked to him/her (buddies). This way, a user entering a shopping mall, leisure centre, disco, etc. would receive a notification if any of the contacts on his mobile phone directory or instant messaging application contact list are in the same location.

• Proximity payments The objective of this service is to allow users to make small monetary transactions with their mobile phones or other handheld devices just by placing it near a kiosk or payment station. Proximity payments are already being applied in multiple scenarios such as vending machines, ticketing, parking meters, public transportation (bus, subway, train…), road tolling, etc.

• Customized multimedia guide The objective of this service is to provide museum visitors with an interactive location-aware multimedia guide. The guide would provide the visitor with the multimedia content (audio, pictures, text, video) according to user’s location, so the users would automatically get the corresponding explanations as he is approaching a work of art.

• Parking space finder The parking space finder service helps drivers to find available spaces when entering an indoor parking garage. Upon request, the service provides the user with information about available parking spaces thanks to the information from a UWB sensor network deployed in the indoor garage.

IV. DESIGN AND DEVLOPMENT OF ADVANCED MULTI-RADIO USER DEVICES

The main objective of the integration of different wireless technologies into user terminals is to develop multi-radio interface user devices, which will allow incorporating new capabilities in the terminals and providing new services. Focusing on the inclusion of UWB radio technology, two stages can be considered. In a first phase, off-the-shelf UWB equipment will be integrated into current terminals, whereas in a second one, advanced UWB platforms will be included in future or enhanced user devices. It is an ongoing process where an evolution of the UWB market and the appearance of improved UWB products are expected. Then, the challenge of having compact user devices with multiple wireless technologies integrated, including UWB, will become achievable.

A. Architecture

During the last decade, the idea of making the diverse networks converge has been broadly discussed. It can be explained from two points of view: services (voice, data, media) and network architecture (mobile, wireless, fixed) with the target of enabling a ubiquitous network. In the context of localization, the technologies present in the access networks (UMTS, HSPA, WiMAX…) and also their complementary (Wi-Fi, Bluetooth…) do not offer the performances needed in terms of accuracy or power consumption. LDR-LT UWB technology allows localising and tracking the users at every moment with a very high accuracy even in indoor environments (unlike GPS) due to the specific characteristics of UWB systems. A first approach of this convergence can be illustrated in the Fig. 3:

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Fig. 3. Location-aware services in heterogeneous networks

B. UWB/HSPA user device

The UWB/HSPA user device will present at least two interfaces: • A LDR UWB interface to connect to other UWB-enabled

devices or a user UWB access point. • A UMTS/HSDPA (High Speed Downlink Packet Access)

interface to access a wide area network. Unlike the HDR UWB systems, where companies involved

in WiMedia Alliance have pushed the standardization and development of applications such as WUSB (Wireless USB), there are very few LDR-LT UWB systems available in the market, and in general they are not compliant with any standard (IEEE 802.15.4a) or even in some cases not compliant with European regulations concerning assigned frequency bands and power limitations, being unsuitable for their integration into smart-phones, PDAs or laptops. As a solution, an IR-UWB LDR-LT platform developed

within the framework of EUWB project and shown in Fig. 4 will be integrated into a mobile user device to demonstrate different location-aware services (indoor navigation, location-based search, proximity marketing…).

Fig. 4. Physical view of the IR-UWB LDR-LT platform (profile/front/packaged)

The integrated LDR UWB/HSPA user terminal will be

composed of: • User device:

o Smartphone o PDA o Laptop with HSPA card

• An IEEE 802.15.4a-based LDR-LT platform with an interfacing RS-232 serial port developed in EUWB project.

• Interface converter between the user device and the LDR-LT UWB platform: an RS-232 to USB converter will be used to provide a more extended USB interface that is likely to be available in most of user devices. Depending on the targeted user device and interface, other possible converters can be used, such as Compact Flash cards and PCMCIA cards featuring a RS-232 serial port, which are provided by different manufacturers.

C. UWB/WIMAX gateway

The UWB/WiMAX user device will include the following features: • An embedded WiMAX card, based on the 802.16e

standard and working in the 3.5GHz band. • An embedded HDR UWB card (for coexistence

purposes). • An embedded card for video process. • An interface to connect to the LDR UWB device (see Fig.

4). Commercial devices with WiMAX or UWB embedded

radio are not available. A first step has consisted to use a laptop to interconnect a WiMAX and a UWB system, see Fig. 5.

Fig. 5. WiMAX and UWB interconnection experimentation platform

The second step will be to integrate these elements in a small rugged box (see Fig. 6). We should be facing to new EMC and coexistence issues that were not raised in the first step. The terminal will be composed of:

• A rugged box equipped with the following items: o A CPU card o A video extension card

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o A mini PCI port to integrate a HDR UWB module

o An express card port to integrate a WiMAX module

o A USB interface to connect an external device (WiMAX or HDR UWB dongle)

o An Ethernet or RS232 interface to connect a LDR UWB external device

Fig. 6. WiMAX and UWB final gateway

The VGA output of the box will allow connecting a monitor

in order to visualize a Graphical User Interface which is in charge of the interaction with the user. It displays the information from the different services and allows the user to configure the application settings and to control the different services. A snapshot of the GUI is shown in the Fig. 7.

Fig. 7. Location GUI

V. DEMONSTRATORS OF LOCATION-AWARE SERVICES

A. Shopping centre

A particular application of LDR-LT UWB-RT is to provide wireless/cellular access network users with location information on indoor environments, which are not covered by satellite-based systems like GPS. Some scenarios for this application are relatively wide indoor environments such as shopping malls, train stations, airports, exhibition centres, sports stadiums, etc. The main requirements of the scenario are listed in Table I.

The main objective of the shopping centre demonstrator is

to build a platform for the development and test of location-aware services in heterogeneous networks. The most important elements of the demonstrator are shown in Fig. 8. • Dual LDR-LT UWB/HSPA device: the dual device gets

its position from the location server through the LDR-LT UWB interface. On the other hand, the device accesses different services through the UMTS/HSPA interface, including new developed services based on location-awareness.

• LDR-LT UWB picocell: it is composed of at least 4 fixed nodes, one of them acting as a picocell coordinator. The distance between the mobile and each fixed node is estimated and transmitted to the location server.

• Location server: the location server application runs on a laptop connected to the LDR-LT UWB picocell coordinator. It receives the ranging information from every node and applies the tracking algorithm to obtain the position of the dual device.

• Service provider: the service provider application runs on a computer that can be physically anywhere, as far as it is connected to the Internet with a public IP address. It receives information requests from the dual device which include the position of the device. The application processes the request and sends the requested information according to the device position.

TABLE I REQUIREMENTS OF THE SHOPPING CENTER SCENARIO

Name Description Tracking Mobile user’s position will be provided by a LDR-

LT UWB system with an accuracy better than 1 meter

Range LDR-LT UWB devices range must be at least 15 meters

Mobility The tracking system will be able to track mobile users at walking pace

User device User device must integrate LDR-LT UWB and HSPA

LDR-LT network configuration

The LDR-LT UWB network will be configured through a GUI connected to the network coordinator

LDR-LT operation Once the network is configured, the LDR-LT UWB nodes will operate autonomously without any user interaction

HSPA access Mobile users devices must have HSPA access to the Internet in order to connect with the service provider

Throughput HSPA access throughput must support the location-based services (at least 1 Mb/s)

Service provider Service provider must have a public IP address Coexistence Peaceful interoperation must be guaranteed

between the different radio technologies involved

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Fig. 8. Location-aware services demonstrator

The LDR-LT UWB network will be deployed in a reduced area of few meters length, which will be a scaled representation of a real indoor environment, for instance a shopping centre. The dual device will move across the area and the position provided by the LT system will be converted into a position in the real shopping centre. On this demonstration platform, multiple location-aware

services will be implemented. Firstly, a navigation application that will provide the dual device with a map of the shopping centre. It will track the user’s movement, being automatically updated according to the user’s position. The user will be able to zoom in/out and scroll the map, ask the application to guide him to a selected place, access information of the different shops/businesses, etc. Another service that will be implemented is location-based search. Information about the shops will be stored in the service provider database together with their position. When the user searches for some kind of business (restaurants, fashion shops, grocery stores...), the search results will be ordered according to the distance to the user. Finally, another possible location-aware service is related to location-aware marketing. The operator will provide the user with information of the shops/businesses when he comes near, for example last bargains when getting near a shop or scheduled films when passing near a cinema. Although the main objective of the platform is the

development and test of location-based services, it can also be used to test different tracking algorithms, location information acquisition, and distribution strategies in the LDR-LT UWB location system.

B. UWB localization of firefighter in indoor environment

The objective of this demonstrator is also to build a platform for the development and test of location-aware services in heterogeneous networks. UWB technology will allow provisioning real time video and firefighter localization services in indoor environment, what is very useful during emergency situations. This scenario is illustrated in Fig. 9. The UWB/WiMAX demonstration platform is focused on

the interconnection of different radio technologies and equipments. It will show through a unique gateway, connected with LDR-LT UWB interfaces, that the information carried by UWB signals can be transmitted through a WiMAX network without weakening.

WiMax base

Station

LDR-LT UWB link or

WiMax linkEUWB Access Point

WiMax CPE-LDR UWB

Fig. 9. UWB localization of firefighter in indoor environment

The main elements of this demonstration platform are: • Dual LDR-LT UWB/WiMAX device: installed on a truck,

it allows the interconnection between firefighters and headquarters. It transmits real time position of firefighters (LDR-LT UWB).

• LDR-LT UWB nodes: these nodes are held by firefighters and implement a location system, which gives the position of each node of the LDR-LT UWB piconet.

• Headquarters: the headquarters is connected to the Internet and can be physically anywhere. It is connected to the dual LDR-LT UWB/WiMAX device thanks to a VPN (Virtual Private Network), which secures the link between the headquarters and the dual LDR-LT UWB/WiMAX device. The headquarters will be able to track in real time each node of the network and will be able to send useful information to the nodes on the field (map of the building, position of the victims).

This scenario requires high accuracy of positioning information and must be independent of classical positioning systems, like GPS, that are not suitable in indoor environment.

VI. CONCLUSION

This paper presents the use of UWB for localization, tracking and navigation in combination with an access network composed of WiMAX or HSPA. Practical scenarios are given and their requirements to implement them. This concept is capable of giving new opportunities for operators and new capabilities for users. Platforms are under development in EUWB project and a first step demonstrator allowed obtaining first results.

ACKNOWLEDGMENT

The work presented in this paper has been carried out within the European research project EUWB which is partly funded by the Commission of the European Union under the 7th European Framework Programme for Research and Technological Development (FP7) and here under the Information and Communication Technologies (ICT) research programme. Moreover, we would like to thank cordially all project partners for their helpful discussions and valuable contributions.

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REFERENCES

[1] EUWB Deliverable D6.3.1 “Requirements and specification of services based on location awareness”. September 2009.

[2] Ana Sierra, Juan Chóliz, Isabelle Bucaille, Ana Villanúa, Ángela Hernández, Ignacio Alastruey, “UWB in Heterogeneous Access Networks”, ICT-MobileSummit 2008, Stockholm, Sweden, 10-12 June 2008.

[3] Juan Chóliz, Ignacio Alastruey, Ángela Hernández, Ana Sierra, Antonio Valdovinos, "Evaluation of cooperative techniques in an interworking UWB-UMTS Platform", 2008 IEEE International Conference on Ultra-Wideband, ICUWB 2008, Leibniz Universität Hannover, Germany, September 10-12, 2008.

[4] S. Steiniger, M. Neun, and A. Edwardes., “Foundations of Location Based Services”. Lecture Notes on LBS, Department of Geography, University of Zürich, 2006.

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