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

WINNER D5.4 v. 1.4
spread of the main arriving wave is found to be less than 1.5 degrees in all LOS scenarios. The weaker
paths in the paper seem to be virtually uniform distributed over the entire azimuth.
5.5.4 Scenario C1
5.5.4.1 Scenario definition
In suburban macrocells base stations are located well above the rooftops to allow wide area coverage.
Buildings are typically low residential houses with one or few floors. Occasional open areas such as parks
or playgrouds between the houses make the environment rather open. Streets have random orientations,
and no urban-like regular strict grid structure is observed. Vegetation is modest.
5.5.4.2 Reference data
WINNER suburban macrocellular measurements were made in a typical Finnish suburban residential area
with rather wide streets. Buildings in the area are mainly one- or two-storey single ore detached houses.
There are open areas between the buildings, such as playgrounds, parks or small forest areas. BS height in
the measurements was ~25 meters, which is well above the surrounding buildings, and at or above the
height of the highest neighbouring trees. Only close to BS there were clear unobstructed LOS areas, and
further away the MS-BS connection was obstructed mainly by trees. Deep NLOS conditions were
achieved at long MS-BS distances. Maximum measured MS-BS distances were ~1100 meters.
5.5.4.3 Path loss
Propagation studies at 5 GHz frequency band in indoor domestic, office and commercial environments
have been frequently <strong>report</strong>ed, but wideband outdoor studies at 5 GHz are not as
numerous. In [YTL02] Yacoub, D.; Teich, W.; Lindner, J., „Capacity of Vehicle-
Bridge MIMO Channels”, TD(02)118, COST 273, 5th Management Committee Meeting,
Lisbon / Portugal, Sep. 19-20, 2002
[ZKVS02] results for urban, suburban and rural environments have been <strong>report</strong>ed. In this case the
maximum mobile (MS) to base station (BS) distances were limited up to 300 meters, which for outdoor
cellular channel modeling is not fully representative. Path loss models around 5 GHz in residential areas
and with BS heights less than 10 meters are <strong>report</strong>ed in [SG00] and [DRX98]
More studies around 2 GHz frequency have been made. In [EGT+99] results for extensive macrocellular
suburban measurements in US have been <strong>report</strong>ed with BS antenna heights 12…79 meters. Maximum
MS-BS distances up to 8 kms were measured in variety of environments containing both hilly and flat
terrains as well as light and moderate-to-heavy tree densities. Shadow fading standard deviation was
found to be in range 5-16 dB, and path-loss exponent was always found to be greater than two. Path loss
exponent was found to have a strong dependency on the BS antenna height and the terrain type: the
higher the BS antenna height the smaller the path-loss exponent.
In [MRA93] and [MEJ91] radio propagation differences between 900 and 1800 MHz centre-frequencies
have been compared in different environments. In both the studies it was found that path-loss values at
900 and 1800 MHz were highly correlated, and there was no significant difference in distance dependent
behaviour. Theoretical free-space path-loss difference between 900 and 1800 MHz is 6 dB, and in flat
open areas a value very close to it, 5.7 dB, was obtained [MRA93]. In suburban areas, however, this
difference was increased to 9.3 dB [MRA93], which was explained to be due to higher vegetation in
suburban environments, which attenuate 1800 MHz signals more than 900 MHz signals. In [MEJ91] PL
differences between 900 and 1800 MHz frequencies were found to be 9…11 dB, i.e. higher than
theoretical free-space loss. In [MRA93] shadow fading standard deviation was found to be approximately
1 dB higher at 1800 MHz, which agrees with results from Okumura [OOKF68].
In [Xia96] it has been theoretically obtained that for BS antennas above surrounding rooftop levels in
suburban and urban macrocells, the path loss increases by 38 dB per decade, and with frequency by 21 dB
per decade. Path loss decreases with the bases station antenna height, with respect to the average rooftop
level, by 18 dB per decade.
Ref. [BBK+02] presents wideband channel measurements at 3.7 GHz and 20 MHz bandwidh in moderate
density macrocellular suburban setting outside Illinois. Reported path-loss exponents are between 2.9 and
3.4, and shadow fading standard deviations vary between 5-10 dB. Maximum measured MS-BS distances
were ~ 6 kms.
Effect of vegetation has been studied in [BBK+04] and it was shown that tree foliage creates an excess
path-loss of between 3 and 7 dBs.
The suburban measurements in the WINNER project were made in a typical Finnish residential area with
a reasonably flat terrain, open streets and modest vegetation. Measurements were done during summer
time, with all trees having their full foliage. Buildings are mainly one- or two-floor single or detached
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