| WIRELESS FLEXIBLE PERSONALIZED COMMUNICATIONS | COST 259 |
| Technical Annex |
 |
| WIRELESS FLEXIBLE PERSONALIZED COMMUNICATIONS | COST 259 |
| Technical Annex |
|
"Wireless Flexible PERSONALIZED Communications"
A. General Background
Mobile communications are evolving from second generation incompatible systems towards the third generation ones, capable of accommodating a variety of services (from voice and data to video and multimedia) tailored to the customer's needs, in different environments (from macro-cells in rural areas to pico-cells, typical of in-building coverage), at different bit rates, according to the acknowledged concept of bandwidth on demand. Therefore, Personal is becoming increasingly PERSONALIZED, through the unique opportunities offered by the radio communication emerging technologies and the related advanced service provision capabilities. Such novel applications face demands for radio system aspects, network aspects, propagation issues, diversity countermeasures to the impairments experienced by the transmission channel, channel allocation strategies and planning tools, different to those addressed in the previous, very successful, COST Action 207 that significantly contributed to the development of GSM specifications. The follow-on Project COST Action 231 that is being finished after a three year extension, has concentrated on second (GSM, DCS@1800, DECT) and third generation systems (UMTS), with only a small Working-Group considering fourth generation systems with transmission rates in excess of 2 Mbit/s and providing bandwidth on demand. This area will become the main focus of mobile radio research over the next five years and will form the central theme of the follow-on Action. COST 231 was also active in establishing and fostering relationships and cross-fertilisation with several Radio Equipment & Systems (ETSI/RES) Groups, RACE Projects and the ITU-Radiocommunication Sector at the international level. The outcome of the presently proposed COST Action 259 is expected to have similar impacts, at the European and the international level as its forerunners, in the evolving of standards towards Personal Communication Services, characterised by a full exploitation of all the mobility aspects and by an increased flexibility.
The title of the Action tries to summarise these objectives, according to the following rationale:
- wireless, to account for both Access Mobility (not only related to mobile communications, but also in terms of Wireless Local Loop, in an increasing perspective of convergence between mobile and WLL technologies), and Terminal Mobility, already provided by current cellular systems;
- flexible, to account for the progressive migration towards third generation systems (UMTS) and their merging into the fourth generation one, in a vision that encompasses a number of services, provided at different bit rates (according to the user's demand) in different bandwidths;
- PERSONALIZED, to stress the concept of Personal Mobility, which is the main feature of the Universal Personal Communications (UPT), in a multi-service perspective, capable to provide a wide range of user applications.
Other currently ongoing COST activities have been examined, in order to avoid any potential overlap and possibly increase the synergistic aspects. Furthermore, also EU funded Projects (ACTS, for example) have been carefully considered, to find commonalities and point out potential integration aspects, taking into account the short-medium term goals of ACTS Projects on one side, and on the other side the spirit of COST Actions, that, although committed to medium-long term research perspectives, have to maintain the necessary (and fruitful) relationships with the activities currently in progress within other bodies. At the same time all potential contributions to standardisation bodies, at European (ETSI) and international level (ITU) have been examined (see Section E regarding co-ordination aspects for further details).
This project is best carried out within COST framework for the following reasons:
- the study requires long-term, multi-disciplinary efforts, involving: radio access technology, propagation modelling, communication theory, coding and modulation schemes, network and protocols aspects, knowledge of planning tool applications, as well as novel test and simulation processes;
- the COST framework, as clearly demonstrated in the past (thanks to its typical bottom-up approach), facilitates a remarkable harmonisation of national research activities.
B. Objectives and benefits
The main objective of the Action is to increase the knowledge of radio system aspects for flexible PERSONALIZED communications, capable of delivering different services, exploiting different bandwidths, and to develop new modelling techniques and related planning tools, in order to guarantee the continuity (and quality) of services, delivered by networks of widely different capabilities and structures, across a number of different environments. Furthermore, in the perspective of a fast evolving demand for interfacing the photonic (glassfibre) network with the wireless network, investigations on the mutual interactions could be carried out, as well. In fact, in the medium/long term scenario envisaged for Telecommunications by the European Commission, the time period 2000 - 2005 would be characterised by the emergence of PCS, with a full integration of user mobility, the Integrated Broadband Communications (IBC) network and the Intelligent Network(s), followed by the Photonic Network implementation at all levels (regional, national and international). In such an environment, the proposed new Action intend to play, in connection with the progressive deployment of the Universal Mobile Telecommunications System (UMTS) and the Mobile Broadband System (MBS), the role performed in the past by:
COST Action 207, in connection with the development of GSM;
COST Action 231, in connection with the deployment of DCS@1800 and the development of UMTS.
The activities will have a significant impact in terms of basic Research & Development and degree of innovation for the Signatories and the whole mobile communications community, with particular reference to the specification bodies. In addition, the typical benefits of a multi-disciplinary work should be experienced, involving a number of expected participating countries and institutions (including Central and Eastern Europe), at least equal to those currently active in COST Action 231. As a secondary but not negligible effect, the support to standardisation bodies from a large community of researchers would provide further stimulations of the personal communication market growth, taking into account the impact of technologies on the life of citizens of the member states, as well as their needs and the economical effects of such technologies.
C. Scientific programme
The above objectives will be reached by co-ordinating the Signatories research in several areas, which cover the above main process:
(i) Radio System aspects, including study on advanced access schemes, bandwidth on demand, equalisation, interference limitation.
(ii) Network aspects, in terms of investigations on spectrum efficiency, identification of channel allocation strategies, study of efficient protocols for high data rates and distributed networks.
(iii) Propagation studies and simulations, using novel promising approaches and the development of models for a sound characterisation of the short range communications radio channel (micro- and pico-cellular environments), together with concurrent validation measurements campaigns.
(iv) Research on intelligent/adaptive antennas, with particular attention on the possible diversity countermeasures they are able to offer and their influence on network planning activities.
(v) Advanced planning tools for a variety of environments, including strategies for optimised frequency assignments.
Work will be carried out according to the following tentative list of Tasks (and/or Sub-Tasks), by imposing well defined deadlines, to facilitate a timely completion of the Action itself:
TASK 1 - RADIO SYSTEM ASPECTS
The activities may be grouped as follows:
Researches on Access Schemes, such as JD(Joint Detection)-CDMA, Slow Frequency Hopping-CDMA, CTDMA (to be considered as a sort of merging of Advanced TDMA schemes into CDMA), Multi-Carrier techniques, in a vision that ensures a progressive and smooth migration from second generation (GSM) to future generation systems; OFDM in particular, seems to be suitable for applications in distributed networks, where an efficient use of non-linear amplifiers is needed, leading to significant out-of-band radiation with non-constant envelope signals;
Studies on flexible rates (bandwidth on demand): UMTS/MBS/WLANs should be characterised by high transport capacity at various data rates, in order to accommodate a multitude of different customised (PERSONALIZED) services in different environments;
Interference limitation studies, aimed at enhancing system performance, using "ad-hoc" interference limitation and power control techniques;
Channel Equalisation: considering that the HIPERLAN (HIgh PErformance Radio LAN) standard has adopted a constant envelope (GMSK) modulation which at 23.6 Mbit/s requires an equaliser for the indoor radio channel, research will be carried out on more efficient equaliser structures for higher order modulations.
The above studies will focus on (but not be limited to) mobile applications, in that also other potentially fast growing sectors will be properly examined, such as the radio in the local loop, in the perspective of a progressive convergence of wireless access technology and mobile radio.
TASK 2 - PROPAGATION
Several topics will be examined from both theoretical and experimental standpoints:
New modelling approaches for UHF and microwave bands, based on the direct solution (using fast computing parallel machines) of Maxwell's equations (for example, the Finite Elements Method (FEM), the Finite Differences in the Frequency or Time Domain Method (FD or FD-TD), the Transmission Line Matrix Method (TLM));
As spectrum at 5.2 GHz, 17.2 GHz and at 40 and 60 GHz has been allocated by CEPT to HIPERLAN and MBS, models will be studied for short range communications in the high microwave and millimetre-wave bands (microcellular and in-building coverage, penetration losses, tree effects, influence of obstructions and car traffic, etc.);
Comparisons between the effectiveness in different situations between empirical/statistical and electromagnetic/deterministic models (ray tracing);
Measurements will be performed, to validate the models, using ad-hoc channel sounders, and to get statistics on wideband parameters to be used for system simulations; this will allow the addition of new features that might improve significantly the efficiency of the computations, while retaining the required accuracy.
TASK 3 - ANTENNAS
Several topics will be examined:
Studies on the effects of the surrounding environment on base station antenna radiation pattern (masts, poles, walls, etc.);
Investigation about intelligent (smart) and adaptive Base Station antennas (in terms of their capability of suppression of interferences, pattern reconfigurability, dual polarisation, etc.);
Investigation on the possibility of using fiberoptic technologies for antenna feeding purposes in the mm-wave band;
Macro and micro diversity techniques, with particular attention to space diversity (detection of angles of arrival of multipath components) and polarisation diversity (orthogonal, slant), in order to optimise the link performance;
Feasibility of various kinds of combined analog/digital beamforming networks for high bit rate transmissions, as it is expected that even very fast ASIC's will not be able to perform the digital processing required to follow high bandwidths in real time; therefore, an optimal distribution between analog and digital parts should be investigated in detail.
For convenience, this Task could be merged with Task 2 into a unified Task on Propagation &Antennas.
TASK 4 - NETWORK ASPECTS
This task will concentrate on the following topics:
Spectrum efficiency and compatibility (frequency sharing with fixed services);
Channel allocation strategies (Fixed and/or Dynamic), best suited to the network and the operating environment;
Studies on efficient protocols for high data rates and for voice and video integration (multimedia), with specific reference to the opportunities offered by ATM access and IBC (Integrated Broadband Communications);
Studies on the interconnecting potential and mutual relations between radio and glass fibre networks;
Distributed Networks: in case where no central controlling node exists, protocols must be designed to support distributed networks; this research area is at a very early stage of its development, with the two WLAN standards so far adopting protocols which are known to be inefficient in the presence of hidden nodes.
TASK 5 - MEASUREMENT ERRORS
This task (which can be considered a Sub-Task of previous Task 2 with direct liaisons with Task 1 too), will examine some topics of paramount importance, that usually are not fully taken into account in the planning process of a mobile communication system:
Analysis of the most usual measurement techniques (Field Strength, Echo Delay Profiles, Scattering Functions, Bit Error Ratios, Frame Errors, System Quality, etc.);
Studies on the impact of the measurements on prediction and planning tools, with the goal to evaluate what share of the discrepancies found can be due to the models and what can be due to measurement uncertainties.
TASK 6 - PLANNING TOOLS
The task will focus on:
Definition of what actual propagation parameters are needed as an input for a planning tool;
Studies on the impact of territorial data bases on outdoor/indoor propagation models performance, in terms of data type, format (raster, vectorial), and resolution (surface and vertical);
Assessment of tools for cellular, micro- and pico-cellular coverage, and coverage of special ambients; these topics will be in particular addressed for systems working at the microwave and millimetre wave bands, taking into account that for future systems non-uniformity of traffic distributions and traffic capacity considerations in most cases will impose restrictions to cell planning, more than propagation constraints themselves;
Network optimisation algorithms by minimisation of mutual interferences;
Frequency assignments strategies, according to the service (or system ) under consideration (re-use pattern, free allocation, underlay and overlay structures, etc.);
Development of an advanced prototype planning tool (or a systematic planning method), capable of coping with the various different network and environmental situations.
This Task may be considered as a Sub-Task of Task 2, with direct liaisons with Task 3 too.
D. Organisation and timetable
D.1 Organisation
The work previously outlined will be split in principle into three Working Groups, according to the block diagram reported below.
Researchers from universities, and engineers coming from operators, manufacturers and research bodies are expected to work in close co-operation with mutual and continuous exchange of information. The information flow and direct interaction between the Groups is expected to be very high; however, it is also foreseen that Sub-Groups dealing with Measurement Errors and Planning Tools would provide straightforward inputs to the Groups dealing with Radio System Aspects and Network Aspects, in addition to Propagation&Antennas Group; the final driving requirements will then flow mainly from these Groups to the Group in charge of Networks Aspects.
Short term missions are envisaged, to encourage the exchange of researchers between laboratories and a subsequent wider dissemination of the results, as well as workshops, to be arranged with invited speakers working in the various fields of interest to the Action and active participation to seminar and conferences, in order to increase the number of external reactions to the ideas, suggestions and proposals originated within the Action.
It is expected that each Working Group will elect a Chairperson to co-ordinate the work within the Group, to ensure the exchange of information with the other Groups and to the whole Management Committee.
The Management Committee will elect a Chair- and Vice-Chairperson, and will be responsible for the interactions with other European or International Bodies, for the mutual transfer of information and exchange of relevant documentation (or any available material, on specific request). It is expected that the Action will establish and foster close liaisons with the following institutions, Projects and Organisations:
Delegates representing Signatories in the Management Committee are expected to:
attend and actively contribute to meetings of the Management Committee (three meetings per year on average are foreseen, one in conjunction with a workshop), according to the objectives and milestones of the Action;
take responsibility for specific items of the Action, when required, and act as liaisons/rapporteurs with the national research groups in their own country;
achieve working liaisons between the Action and other related COST Telecommunication and Information Science Actions, according to the recommendations of the Technical Committee of Telecommunications (TCT).
D.2 Timetable
A bar-chart showing the time implications of the various activities outlined in Tasks 1 to 6 and the related expected outputs/results is reported in the following.
Due to the nature of the Action, annual workshops will be organised; as usual, the Chairperson will take care of the preparation of the Annual Reports. It is in the proposers' mind to have all documentation available in electronic form for easy distribution and transmission to other bodies. Moreover, all the technical temporary documents could be in principle (subject to the approval of the interested Signatory) put in the WWW for world-wide dissemination; this requires the establishment of a site in the WWW for the Action (the experience of previous COST Actions in this respect will be of great help).
The envisaged three-year activity would produce significant results, to be summarised in the Final Report which the proposers consider should be published as a book by an external publisher (as it is being done for COST 231 Action), in order to achieve a wide dissemination of results, just before the start of FPLMTS/UMTS services, expected at the turn of the century.
E. Economic dimension
The 20 COST Countries involved in COST 231 have actively participated in the preparation of the Action, or otherwise indicated their interest.
Estimated number of Signatories (at regime, on the basis of current COST231 participation): 20
Cost per Signatory per year (at 1993 figures):
1 Year Scientist ECU 60 000
2 Year Technician ECU 80 000
3 Year Student ECU 75 000
Travel/subsistence expenses ECU 15 000
Total per year ECU 230 000
Total over 3 years ECU 690 000
Costs for the 3-year life of the Action (at 1993 figures):
Total ECU 690 000 x 20 ECU 13,8 Million
+ 10% overhead for running/operational costs ECU 1,38 Million
Total Cost to national funds ECU 15,18 Million
EU overhead (over 3 years) 3 x ECU 60 000 ECU 0,18 Million
Economic Dimension ECU 15,36 Million
Economic Dimension
(at 1996 costs, considering a 15% increase)
ECU 17,7 Million