Final report on link level and system level channel models - Winner

WINNER D5.4 v. 1.4
1. Introduction
WINNER project is aiming at a Beyond-3G (B3G) radio system using a frequency bandwidth of 100
MHz for one radio connection and a radio frequency lying most probably somewhere between 2 and 6
GHz in spectrum. The research concerning the suitability of certain communication parameters, like
modulation, coding, symbol rate, MIMO antenna utilisation etc., is performed through extensive
simulations. The simulation results depend strongly on the radio channel. Hence, the radio channel is a
crucial part of the simulation. On one hand, it is very important to use a very accurate and realistic
channel model in the simulation to enable reliable simulation results. On the other hand, the complexity
of the simulation should be kept low. Therefore, the research challenge is to create a channel model which
is realistic enough and simple.
WINNER Work Package 5 (WP5) is focused on multi-dimensional radio channel modelling. Totally six
partners are involved in WP5, namely Elektrobit (EBIT, in year 2004, and Elektrobit Testing EBITT in
year 2005), Helsinki University of Technology (HUT), Nokia (NOK), Royal Institute of Technology in
Stockholm (KTH), Swiss Federal Institute of Technology Zurich (ETHZ), and Technical University of
Ilmenau (TUI). Up to now, the situation is such that there are no widely accepted channel models
available which are suitable for WINNER system parameters. Therefore, WINNER WP5 has to create
new channel models needed in the project. For the initial purposes, WP5 selected and recommended two
existing channel models, which are called initial channel models [D5.1]. The models are 3GPP/3GPP2
Spatial Channel Model (SCM) [3GPP SCM] for outdoor simulations and IEEE 802.11n MIMO model
[802.11n] for indoor simulations. Because the SCM model was not suitable for WINNER simulations as
such, WP5 performed some modifications and implemented the extended SCM model (SCME) [SCME].
However, in spite of these modifications, the initial channel models were not good enough for the
advanced simulations. Consequently new WINNER models are needed.
The WINNER channel models were implemented in two steps. In the first step, channel models for the
most urgently needed propagation scenarios with a limited number of parameters were created.
Propagation scenario means here the propagation environment and certain propagation related parameters
specified to meaningful values. The main difference between different propagation scenarios exists due to
the diverse environments. Channel model parameters were defined for five propagation scenarios
(prioritised scenarios) according to [D7.2], namely indoor small office (A1), urban micro-cell (B1),
stationary feeder (B5), urban macro-cell (C2), and rural macro-cell (D1). These models are described in
the deliverable D5.3 [D5.3]. In the second step the channel models were upgraded so that more
parameters are included in the models. Two more scenarios – indoor (B3) and suburban (C1) – are also
included based on the feedback from other work packages. The channel models created in the first step,
and updated in the second step, are described in this deliverable, D5.4.
In this deliverable, we describe a generic channel model framework that is subsequently used as a basis
for the channel models of all scenarios, except B5. Furthermore, we present clustered delay line (CDL)
models for calibration and comparison simulations. The generic modelling approach allows the creation
of virtually unlimited double directional radio channel realizations. The generic channel model is a raybased
multi-link model that is antenna independent, scalable and capable of modelling channels for
MIMO connections. The models are based on the existing literature and the parameters extracted from
eleven measurement campaigns performed by the WP5. The selection of the model parameters is based
both on the measurements and information found in the literature. The measurements were performed by
five partners, namely EBIT/EBITT, HUT, KTH, NOK, and TUI. Different channel sounders, most of
them capable of measurements at 2 and 5 GHz frequency ranges and 100 MHz bandwidth, were used.
Measurement results were analyzed using beam-forming and super-resolution methods. The analyzed
items, e.g. path loss, shadow fading characteristics, power delay profiles, delay spreads, angle-spreads,
and cross-polarisation ratio (XPR), were analyzed for the scenarios of interest.
In WP5 one activity has been the implementation of the 3GPP/3GPP2 SCM channel model. The model
was implemented in software by the WP5. Later, its extension to 5 GHz frequency range and 100 MHz
bandwidth [SCME] was implemented. The extension work has been published in [BGS+05].
We have compiled a set of requirements from various documents, specifically the WP2 Channel Model
Requirements, the WP5 Deliverable D5.2 [D5.2], WP7 deliverable D7.2 [D7.2], and <strong>report</strong>ed
shortcomings of the channel models selected for initial usage [D5.1]. The main requirements are proper
characterisation of spatial properties for MIMO support, large set of possible channels as well as some
limited randomness channels, consistency in time, frequency and space, e.g. inherent link between angle
spectrum and Doppler spectrum, time-variability of bulk parameters, and extended polarisation support.
The document is organized in a way to provide best readability. Its overall content is divided into 2 major
parts. The first part is relatively short and contains the core information provided in this deliverable. Part I
begins with an introduction, background information concerning our approach, and the requirements on
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