WINNER II pdf - Final Report - Cept

WINNER II D1.1.2 V1.2
The feeder scenarios are specified here in connection of the micro-cellular environment. Actually the
feeders can be used also in the macro-cellular cases. In this document it is assumed that the useful macrocellular
feeder link, C5, is identical with the feeder model B5c.
2.3.7.1 B5a
The signal in B5a can be assumed to consist of a strong LOS signal and single bounce reflection. Also far
away reflections can occur. The connection is almost like in free space, so that the path-loss does not
depend noticeably on the antenna heights. For this scenario fixed angle spread, delay spread and XPR
values are applied. Directive antennas are very effective in reducing the delay spread and other multi-path
impacts as explained in [PT00]. However, the model is applicable for omni-directional antennas for up to
300 meters in distance. By using directive antennas the range can be extended approximately to 8 km.
A static (non-fading) channel component is added to the impulse response. We select its power to be 10
dB. The power-delay profile (of all paths except the direct) is set as exponential, based on the results in
[OBL+02] and [SCK05]. The shadow fading is Gaussian with mean zero and standard deviation of 3.4 dB
based on [PT00]. B5a sub-scenario was specified and modelled in [WIN1D54]. The same channel model
is used also in Phase II.
2.3.7.2 B5b
In B5b it is assumed that both the transmitter and receiver have many scatterers in their close vicinity
similar as theorized in [Sva02]. In addition there can also be long echoes from the ends of the street.
There is a LoS ray between the transmitter and receiver and when this path is strong, the contribution
from all the scatters is small. However, beyond the breakpoint distance the scatterers start to play an
important role.
In papers e.g. [Bul02], [SBA+02] the results for different carrier frequencies are very similar. Therefore,
in B5b model the frequency is disregarded. The principle adopted for the WINNER phase 1 model allows
for various correlations between different parameters such as angle-spread, shadow-fading and delayspread.
In this case, dependency between path loss and delay-spread [MKA02] is applied. This
dependence is handled by selecting one of three different CDL models given in [WIN1D54]. Based on the
delay-spread formula in [MAS02] we select the delay spread to be 30 ns when the path loss is less than 85
dB, 110 ns when the path loss is between 85 dB and 110 dB, and finally 380 ns when the path loss is
greater than 110 dB. With these settings the delay-spread used here is a factor 40%-156% of the delayspread
formula of [MAS02] for path losses up to 137 dB. We call these path-loss intervals range1, range2
and range3 and different clustered-delay line models will be provided for the three cases.
In terms of path loss, the break point distance calculated as
( h − h )( h − h )
b 0 b 0
rb = 4
λ
(2.2)
becomes important leading to so called two slope -model. The power delay profile (of all paths except the
direct) is set as exponential, based on the results in [SMI+00]. A per-path shadow fading of 3 dB is used
to obtain some variation in the impulse responses. A static (non-fading) channel component is added to
the impulse response. Based on [FDS+94] we select this parameter to be 10 in range1, 2 in range2, and 1
in range3. Also K-factor changes according to range. B5b sub-scenario was specified and modelled in
[WIN1D54]. The same channel model is used also in Phase II.
2.3.7.3 B5c and B5d
Scenarios B5c and B5d can be considered as LOS of B1 and NLOS of C2 respectively. Only support for
Doppler spectrum of stationary cases has to be introduced. B5c is probably the most important feeder link
scenario, because it will be used in urban micro-cell relay scenario. B5c is almost identical to the B1
micro-cellular LOS scenario. The only difference in environment is the assumed antenna height of the
mobile/relay. Same channel model will cover both of the cases, except the difference in Doppler spectrum
(mobility). Feeder link ends are stationary and the Doppler frequency results from motion of the
environment. In scenario B5c some clusters represent vehicles with speed of ~50 km/h and the rest of the
clusters represent stationary objects like walls and building corners.
Actually B5d seems less useful for a feeder link scenario. Therefore it is not discussed here further.
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