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

WINNER D5.4 v. 1.4
delay spread values typically vary between 200…800 ns, the median being around 350 ns. Log-normal
distribution was found to give a good fit to the measured delay spread distribution. In typical urban
environments delay spreads were found to decrease with increasing BS antenna height.
In [WHL+93], RMS delay spread distributions were compared in different environments at 900 MHz and
1900 MHz centre-frequencies. With both frequencies the used chip rate was 10 MHz, and data was
recorded simultaneously with both the frequencies. It was seen that propagation behaviour in teRMS of
RMS delay spread was very similar with both the centre-frequencies in semirural, suburban and urban
cells.
Delay spread characteristics for 3.7 GHz centre-frequency with 20 MHz bandwidth are given.
Measurements were made in suburban areas outside Chicago, where also some distant high-rise buildings
were in the environment. BS height was 49 meters, and MS was installed at 2.7 meters above the ground.
15 dB dynamics criterion from the max peak power was used in calculating delay spreads. Median delay
spread values for LOS and NLOS propagation conditions were 240 and 360 ns, respectively. The
combined delay spread was found to be 300 ns. As for number of rays, defined as local maxima of
(instantaneous) power delay profiles, 90 percentile value of the cdf for LOS, NLOS and combined data
were 3, 8 and 7 rays, respectively.
In our WINNER measurements typical delay spreads were of the order of 13…125 ns, which are
considerably smaller values than <strong>report</strong>ed by [AlPM02]. One reasons for the difference is the higher BS
antenna position. Rms delay spreads have often been <strong>report</strong>ed to show log-normal distribution, as
summarized for example in [GEYC]. However, instead of Gaussian, we have fitted a gumbel distribution
to log10(DS), which shows a better match.
5.5.4.5 Angle-spreads
Azimuth spreads at BS have been given in [Pa03] for rural and suburban environments at 2 GHz centrefrequency
and 10 MHz bandwidth. The mean angle-spread of 2 degrees was found, with standard
deviation of 2 degrees. In urban areas they have been <strong>report</strong>ed to be 14 degrees and 5 degrees,
respectively. The difference between the geometrical direction of the mobile and the direction of
maximum received power was modeled as Gaussian. The standard deviation is about 16 degrees near the
base station and decreased to 8 degrees far away in urban environment. In rural and suburban is much
smaller, 2.7 degrees when distance is below 2 kms and above this decreases to 1.7 degrees. Mobile
azimuth spreads were <strong>report</strong>ed as 35 degrees in suburban, and 20 degrees in rural environment.
5.5.5 Scenario C2
5.5.5.1 Scenario definition
In urban macro cells base stations are located above roof tops to allow wide area coverage. Typical
buildings comprise several floors (> 4) and street grids often form reguiar grid. Vegetation is modest if
any, and streets are occupied with pedestrian and vehicular traffic.
5.5.5.2 Reference data
Macrocellular data measured outside WINNER-project in Helsinki city centre at 5.3 GHz centrefrequency
and 100 MHz chip rate was used for C2 parameter extraction. The BS height in the
measurements was ~40 meters, which is above the nearby surrounding buildings. Typical building height
in the area was 4-7 stories. The measured data consists mostly NLOS or OLOS routes, but also some LOS
sections in vicinity of the BS.
5.5.5.3 Path loss
COST231-Hata path-loss model [Cost231] is valid in frequency range from 1500-2000 MHz, BS-MS
distances > 1 km, BS heights 30-200 meters and MS heights 1-10 meters. For urban macrocells the model
is written as
d
PL = ( 44.9 − 6.55log
10
( hBS
)) log
10
( ) + 48.5 + (35.46 −1.1h
MS
)log
10
( f
c
) −13.82 log
10
( hBS
) + 0. 7h
1000
(5.42)
In above all the distances and heights are given in meters, and centre-frequency f c is given in MHz. With
h BS = 35 m, h MS = 2 m, and f c = 2000 MHz the model becomes
PL = 31.0
+ 34.8log
10
( d )
(5.43)
The path-loss model obtained from 5.3 GHz macrocellular NLOS measurements in Helsinki city centre is as follows:
PL = 53.5
+ 28.3log
10
( d),
σ = 5.7
(5.44)
MS
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