Page 323 - Integrated Wireless Propagation Models

I n - B u i l d i n g ( P i c o c e l l ) P r e d i c t i o n M o d e l s 301

the nondiffraction area and the diffraction area. Two empirical formulas are formed as
follows:
1L, (d) = L(d0 ) + 1m, log d (for diffraction area) (5.3.2.2.2.10)
2L, (d) = L(d0) + 2m, log d (for nondiffraction area) (5.3.2.2.2.11)
where n associated with m is the number of floor separations, m, is the path slope, and
d is the distance from the transmitter to the receiver; d0 is the minimum distance from
the transmitter to the receiver. The numbers 1 and 2 associated with symbols are used
to distinguish two different areas:

1. Moving on the one-separated floor (n = 1):
1m1 = 14 dB/dec
1 m = 17 dB/dec
2
2. Moving on the two-separated floor (n = 2):
2m1 = 22 dB/ dec
2m2 = 25 dB/ d ec

From the above empirical formulas, we have found that on both one-separated and
two-separated floors, the slopes measured in the diffraction area are less attenuated
than in the nondiffraction area by 3 dB I dec along the distance from the transmitter to
the receiver.
Also, the slope of path loss when moving on the one-separated floor is less attenu­
ated than on the two-separated floor by 6 dB I dec along the distance from the transmit­
ter to the receiver.
The total interfloor path loss can be summed up the floor separation losses from
three scenarios; the floor separation loss from Eq. (5.3.2.2.2.1) and Eq. (5.3.2.2.2.5), and
the moving-on separated floor loss from Eq. (5.3.2.2.2.10) or Eq. (5.3.2.2.2.11) as

L n = L ' . 1 + L ". 1 + L (d) (5.3.2.2.2.12)
mter oor 1- 1- 1 11
where j = 1 is for measuring at the diffraction area and j = 2 is for measuring at the
nondiffraction area.
In every case, the user may want to convert the transmitter-to-receiver distance to
the distance measured from the minimum distance d0 on the floor where the receiver is
located. These measured data have highlighted some thoughts in predicting the inter­
floor cases.
5.3.2.3 An l n terbuilding Case

5.3.2. . 1 Description of the Case
3
Measurement data were collected at the north wing from the APs situated in the north
wing. Again, due to the limitation of the ERP allowed (1 mw), only limited measure­
ment data were collected.
Based on the specific layout of this building, from Fig. 5.3.2.3.1, the corridor junc­
tion has the same floor heights as the north and south wings. Thus, measured data
points were divided into two groups: one collected from the propagation with shadow
loss and the other from the propagation without shadow loss. The measured data at
2.4 GHz were plotted and are shown in the next section.