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

WINNER D5.4 v. 1.4
Figure 5.85: Comparison of the path-loss models of [OBL+02], [PT00], free-space and a path-loss
model we obtain from the results in [Dug99].
In [SKE05], roof-top to roof-top MIMO measurements at 5.2 GHz are presented. Four different links with
distances of 210, 55, 180, 116 meter have been measured all with clear LOS. Measurement results include
Doppler, K-factor, delay-spread, power-delay-profile, frequency correlation and plots DoA/DoD superresolution
results from two out of the four links. Doppler spreads of around 1 Hz at the 10 dB level. This
spectrum seems to be identical in the measurements for all delay components. The K-factors measured
are in the range 9.6 to 17.5 dB. The measured power delay profiles seem to be similar to a direct
component plus exponential decay with some randomization. Mean delay-spreads are in the range 6-30
ns. The super-resolution plots show many components but most of them are very weak. A reasonable
guess using only the plots is a power-weighted RMS delay-spread of 2 degrees.
5.5.3.3 Scenario B5b - street-level-to-street-level
A classical two ray model with ground reflection results in a so-called breakpoint distance located at a
distance r
b given by
λ
h h
r 4
b m
b
= , (5.34)
where hb
and hm
are the heights of the two ends of the link, respectively. When the distance between the
two antennas is smaller than r b almost free-space path-loss is experienced. This has been observed in a
number of studies [SBA+02], [OTH00], [SMI+00], [MKA02], [FBR+94] but due to reflections from cars
and other objects during traffic the actual breakpoint occurs at
4 * (h b – h 0 ) * (h m – h 0 ) / λ (5.35)
where h0
is an effective ground height of typically 1.2-1.6 meters. At 5GHz we thus need 3.5 to 4 meter
high antennas to achieve 380 meter free-space propagation.
In [SBA+02] and [Bal02] path loss and delay-spread measurements at 1.9 GHz and 5.8 GHz are
performed in a scenario similar to what is considered here. The transmitter antenna is biconical and
mounted six meters above ground in two different locations. The receiver antenna is omni-directional
mounted on a minivan at 1.7 meters height and is mobile. The fading patterns at 1.9 GHz and 5.8 GHz are
said to be “remarkably similar” although the measurements were not carried out simultaneously at the two
frequencies. No obvious difference LOS and NLOS streets were found in teRMS of the difference in path
loss between the two frequencies. The distribution of the difference between 1.9 GHz and 5.9 GHz path
loss (in dB) is said to be modelled well by a Gaussian distribution with standard deviation 4 dB for both
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