Wireless Network Design: Optimization Models and Solution ...

56 K. V. S. Hari
Table 3.3 Impulse response coefficients for the outdoor to indoor and pedestrian scenario
Tap Channel A Channel A Channel B Channel B
Relative Relative Relative Relative
Delay(ns) Avg Pwr(dB) Delay (ns) Avg Pwr (dB)
1 0 0 0 0
2 110 -9.7 200 -0.9
3 190 -19.2 800 -4.9
4 410 -22.8 1200 -8.0
5 – – 2300 -7.8
6 – – 3700 -23.9
Table 3.4 Impulse response coefficients for the vehicular scenario
Tap Channel A Channel A Channel B Channel B
Relative Relative Relative Relative
Delay(ns) Avg Pwr(dB) Delay (ns) Avg Pwr (dB)
1 0 0 0 -2.5
2 310 -1.0 300 0
3 710 -9.0 8900 -12.8
4 1090 -10.0 12900 -10.0
5 1730 -15.0 17100 -25.2
6 2510 -20.0 20000 -16.0
τ 2 rms =
L−1
∑ Pl τ
l=0
2 l − τ2 avg
(3.17)
where Pl is the power (variance) of the amplitude of the lth path. Some experiments
were conducted to measure the power delay profiles [21, 48]
We now present some of the typical frequency selective channel model parameter
values used in practice for the indoor channel case in the 2-2.5GHZ band.
Table 3.5 Delay spread values for indoor channels
Channel A RMS(ns) Channel B RMS(ns)
Indoor Office 35 100
Outdoor to Indoor and Pedestrian 45 750
Vehicular high antenna 370 4000
3.4.6 Decorrelation Distance of the Channel
The space-time wireless channel has some interesting properties with respect to the
spatial dimension [3]. The spatial correlation function of the channel can be obtained
as a function of the space dimension. The distance at which the magnitude of the
correlation takes the value zero (in practical systems, close to zero) is the decorrela-