CEPT
ECC
SE44(13)121
Electronic Communications Committee
Project Team SE44
12th meeting of WGSE Project Team SE44
Mainz, Germany
17.12. – 18.12.2013
Source: Aero3G
Subject: Compatibility between RLAN and DA2GC (ETSI TR 103 108)
Date issued: 10.12.2013
Group membership required to read? (Y/N): N
Summary:
This contribution presents compatibility analyses between DA2GC (TR 103 108) and RLAN.
From the analyses undertaken it may be concluded that:



There would be no unacceptable interference between the DA2GC AS and deployed
RLANs.
Any interference between the DA2GC GS and indoor RLANs is unlikely because of
modest wall attenuations assumed.
For the outdoor RLAN case any interference is likely to be improbable given the expected
number of outdoor users. With the omni antenna mitigation is possible by applying a
minimum separation distance or for the RLAN to select an alternative channel. Indeed
DFS may initiate this automatically. With the directional antenna the probability of
interference low but mitigation can be introduced using site screening or simply using an
alternative RLAN channel.
The overall conclusion is that DA2GC and the proposed RLAN would be operationally compatible
because the probability of unacceptable interference is very low.
However, if any RLAN operation in the band 5855 MHz to 5875 MHz could be restricted to indoor
use then essentially there would be no interference.
Proposal:
SE44 is invited to consider these results when considering the issue of RLAN compatibility.
Background:
.
Contents
1
Introduction ....................................................................................................................... 3
2
Compatibility between DA2GC AS (Victim) and RLAN (Source) .................................... 3
2.1
2.1.1
Single Cell ............................................................................................................. 3
2.1.2
Visible Cells ........................................................................................................... 5
2.1.3
Cell Distribution ..................................................................................................... 6
2.1.4
Aggregate Interference for Single Cell ................................................................... 7
2.1.5
Aggregate Interference from a Cluster of Cells ...................................................... 7
2.1.6
RLAN Antennas..................................................................................................... 7
2.2
3
Propagation ........................................................................................................... 8
3.1.2
Aircraft Station Altitude Mitigation .......................................................................... 8
3.1.3
Unwanted Interference .......................................................................................... 9
Results ......................................................................................................................... 9
Compatibility between DA2GC GS (Victim) and RLAN (Source) .................................. 10
4.1
Methodology ............................................................................................................... 10
4.1.1
Propagation ......................................................................................................... 10
4.1.2
Unwanted Interference ........................................................................................ 11
4.2
Results ....................................................................................................................... 11
Compatibility between DA2GC GS (Source) and RLAN (Victim) .................................. 12
5.1
Methodology ............................................................................................................... 12
5.1.1
Propagation ......................................................................................................... 12
5.1.2
Unwanted Interference ........................................................................................ 12
5.2
6
Methodology ................................................................................................................. 8
3.1.1
3.2
5
Results ......................................................................................................................... 8
Compatibility between DA2GC AS (Source) and RLAN (Victim) .................................... 8
3.1
4
Methodology ................................................................................................................. 3
Results ....................................................................................................................... 13
Conclusions ..................................................................................................................... 14
Table 1 : Breakdown of RLAN Users ............................................................................................................ 4
Table 2: Propagation Parameters ............................................................................................................... 10
Table 3: Propagation Parameters ............................................................................................................... 12
Figure 1 : Visible RLAN Cells ........................................................................................................................ 5
Figure 2 : Distribution of RLAN Cells ............................................................................................................ 6
Figure 3 : DA2GC AS Victim / RLAN Source ................................................................................................ 8
Figure 4: Aircraft Station Altitude Mitigation .................................................................................................. 8
Figure 5 : DA2GC AS Source (10km) / RLAN Victim ................................................................................... 9
Figure 6 : DA2GC AS Source (3km) / RLAN Victim ................................................................................... 10
Figure 7 : DA2GC GS Victim / RLAN Source ............................................................................................. 11
Figure 8 : DA2GC GS Source / RLAN Victim ............................................................................................. 13
2
1 Introduction
This contribution analyses the compatibility between the proposed RLAN deployment, in the
band 5855 MHz to 5875 MHz, and DA2GC according to ETSI TR 103 108. The analysis uses
RLAN parameters detailed in SE44 #12 Meeting Info 3 and SE44(13)118.
2 Compatibility between DA2GC AS (Victim) and RLAN (Source)
2.1
Methodology
2.1.1
Single Cell
Among other things SE44(13)118 defines a representative cell of radius 30 km. It comprises
urban, suburban and rural areas. The number of RLAN users for each area is given in terms of:



Transmitter power
Indoor/Outdoor
Bandwidth
Using this information the following table has been derived:
3
TX dBm
Active co-channel RLANS
Nbr Indoor 1000 mW (Omni)
Nbr Indoor 1000 mW (Omni)
Nbr Indoor 1000 mW (Omni)
Nbr Indoor 1000 mW (Omni)
Nbr Indoor 200 mW
Nbr Indoor 200 mW
Nbr Indoor 200 mW
Nbr Indoor 200 mW
Nbr Indoor 80 mW
Nbr Indoor 80 mW
Nbr Indoor 80 mW
Nbr Indoor 80 mW
Nbr Indoor 50 mW
Nbr Indoor 50 mW
Nbr Indoor 50 mW
Nbr Indoor 50 mW
Nbr Indoor 25 mW
Nbr Indoor 25 mW
Nbr Indoor 25 mW
Nbr Indoor 25 mW
Nbr Outdoor 1000 mW (Directional)
Nbr Outdoor 1000 mW (Directional)
Nbr Outdoor 1000 mW (Directional)
Nbr Outdoor 1000 mW (Directional)
Nbr Outdoor 1000 mW (Omni)
Nbr Outdoor 1000 mW (Omni)
Nbr Outdoor 1000 mW (Omni)
Nbr Outdoor 1000 mW (Omni)
Nbr Outdoor 200 mW
Nbr Outdoor 200 mW
Nbr Outdoor 200 mW
Nbr Outdoor 200 mW
Nbr Outdoor 80 mW
Nbr Outdoor 80 mW
Nbr Outdoor 80 mW
Nbr Outdoor 80 mW
Nbr Outdoor 50 mW
Nbr Outdoor 50 mW
Nbr Outdoor 50 mW
Nbr Outdoor 50 mW
Nbr Outdoor 25 mW
Nbr Outdoor 25 mW
Nbr Outdoor 25 mW
Nbr Outdoor 25 mW
Totals
B/W
30.0
30.0
30.0
30.0
23.0
23.0
23.0
23.0
19.0
19.0
19.0
19.0
17.0
17.0
17.0
17.0
14.0
14.0
14.0
14.0
30.0
30.0
30.0
30.0
30.0
30.0
30.0
30.0
23.0
23.0
23.0
23.0
19.0
19.0
19.0
19.0
17.0
17.0
17.0
17.0
14.0
14.0
14.0
14.0
20.00
40.00
80.00
160.00
20.00
40.00
80.00
160.00
20.00
40.00
80.00
160.00
20.00
40.00
80.00
160.00
20.00
40.00
80.00
160.00
20.00
40.00
80.00
160.00
20.00
40.00
80.00
160.00
20.00
40.00
80.00
160.00
20.00
40.00
80.00
160.00
20.00
40.00
80.00
160.00
20.00
40.00
80.00
160.00
Table 1 : Breakdown of RLAN Users
4
% B/W
0.10
0.25
0.50
0.15
0.10
0.25
0.50
0.15
0.10
0.25
0.50
0.15
0.10
0.25
0.50
0.15
0.10
0.25
0.50
0.15
0.10
0.25
0.50
0.15
0.10
0.25
0.50
0.15
0.10
0.25
0.50
0.15
0.10
0.25
0.50
0.15
0.10
0.25
0.50
0.15
0.10
0.25
0.50
0.15
Urban Suburban
15656
23520
7.36
11.06
18.41
27.65
36.81
55.30
11.04
16.59
25.77
38.71
64.42
96.78
128.84
193.56
38.65
58.07
47.86
71.90
119.64
179.74
239.28
359.48
71.78
107.84
25.77
38.71
64.42
96.78
128.84
193.56
38.65
58.07
68.10
102.31
170.25
255.78
340.51
511.56
102.15
153.47
0.01
0.02
0.03
0.04
0.05
0.08
0.02
0.02
0.37
0.55
0.92
1.38
1.84
2.77
0.55
0.83
1.29
1.94
3.22
4.84
6.44
9.68
1.93
2.90
2.39
3.59
5.98
8.99
11.96
17.97
3.59
5.39
1.29
1.94
3.22
4.84
6.44
9.68
1.93
2.90
3.68
5.53
9.20
13.83
18.41
27.65
5.52
8.30
1839
2763
Rural
4935
2.32
5.80
11.60
3.48
8.12
20.31
40.61
12.18
15.09
37.71
75.43
22.63
8.12
20.31
40.61
12.18
21.47
53.67
107.34
32.20
0.00
0.01
0.02
0.00
0.12
0.29
0.58
0.17
0.41
1.02
2.03
0.61
0.75
1.89
3.77
1.13
0.41
1.02
2.03
0.61
1.16
2.90
5.80
1.74
580
2.1.2
Visible Cells
The number of visible cells, assuming a uniform distribution, depends on the radio horizon and
hence the height of the aircraft.
The radio horizon is given by:
𝑑𝑟ℎ = 4.12 × √( ℎ)
Where
drh = radio horizon in km
h = aircraft height in metres
The area of a single cell is 2827 sq km.
The area visible by the aircraft station is given by:
𝜋 × (𝑑𝑟ℎ )2
The number of visible cells is given by:
area visible by the aircraft station
area of a single cell
Total Visible Cells
250
200
150
100
50
0
3
4
5
6
7
8
9
Aircraft Height (km)
Figure 1 : Visible RLAN Cells
5
10
11
12
2.1.3
Cell Distribution
A hexagonal distribution, as illustrated below, is assumed with the aircraft station immediately
above the centre cell.
Figure 2 : Distribution of RLAN Cells
6
2.1.4
Aggregate Interference for Single Cell
The aggregate interference transmitted by a single cell is calculated using the distribution of
RLAN users in terms of:





Indoor/Outdoor use
Transmitter power
Bandwidth
Clutter attenuation according to elevation angle
Wall attenuation for indoor users only
Aggregate is calculated using the equation:
10 ∗ 𝑙𝑜𝑔10(∑ 10
𝑃𝑤𝑟𝑑𝐵𝑚
10
))
First the aggregate for each variant of transmission is derived using the equation:
𝑇𝑥 − 𝐵𝐹 − 𝐶𝑙𝑢𝑡𝑡𝑒𝑟 − 𝑊𝑎𝑙𝑙
Where:




Tx : transmitter power in dBm
BF : Bandwidth factor in dB
Clutter: Clutter attenuation in dB according to SE44(13)118
Wall : Wall attenuation 15 dB
It is recognised that the wall attenuation of 15 dB may be pessimistic.
Finally the total aggregation, as seen from the cell centre, is calculated for the entire cell taking
into account the RLAN antenna patterns.
2.1.5
Aggregate Interference from a Cluster of Cells
This aggregate is calculated using the single cell aggregate interference as the basis. A cluster
of visible cells is generated depending on aircraft height and the aggregate interference, taking
into account the slant distance between the respective visible cluster and the aircraft, is
determined.
2.1.6
RLAN Antennas
For the purposes of this analysis the following patterns have been assumed:
Omni: Pattern according to SE44 #12 Meeting Info 3
Directional: 18 dBi gain, 20 degree beamwidth using ITU-F.1336-3 pattern.
7
2.2
Results
The result of this analysis is given below:
DA2GC AS Victim - RLAN Source
-110
-120
dBm/MHz
-130
-140
3
4
5
6
7
8
9
10
11
Aircraft Height (km)
DA2GC Threshold (dBm/MHz)
Total Aggregate Interference (dBm/MHz)
Figure 3 : DA2GC AS Victim / RLAN Source
It is concluded that the anticipated RLAN deployment would not cause interference to the
DA2GC AS even if modest wall attenuation is assumed.
3 Compatibility between DA2GC AS (Source) and RLAN (Victim)
3.1
Methodology
3.1.1
Propagation
For air/ground propagation Free Space Loss, as defined below, has been used:
𝐹𝑆𝐿 = 32.44 + 20𝑙𝑜𝑔10 (𝐹𝑟𝑒𝑞𝑀𝐻𝑧 ) + 20𝑙𝑜𝑔10 (𝐷𝑖𝑠𝑡𝑎𝑛𝑐𝑒𝐾𝑚 )
3.1.2
Aircraft Station Altitude Mitigation
As described in ETSI TR 103 108, the aircraft station Eirp is attenuated as a function of altitude
according to the figure below:
24
22
20
18
16
14
dB 12
10
8
6
4
2
0
0
1
2
3
4
5
6
7
8
9
Altitude (km)
Figure 4: Aircraft Station Altitude Mitigation
8
10
11
12
12
3.1.3
Unwanted Interference
The unwanted interference into RLAN has been calculated according to the following equation:
𝐼𝑛𝑡𝑒𝑟𝑓𝑒𝑟𝑖𝑛𝑔 𝑆𝑖𝑔𝑛𝑎𝑙 = 𝐸𝑖𝑟𝑝𝑆𝑜𝑢𝑟𝑐𝑒 − 𝐴𝑆𝑀𝑖𝑡𝑖𝑔𝑎𝑡𝑖𝑜𝑛 − 𝐿𝑜𝑠𝑠𝑃𝑟𝑜𝑝 + 𝐴𝑛𝑡𝑒𝑛𝑛𝑎 𝐺𝑎𝑖𝑛𝑅𝑥
For DA2GC, both 𝐸𝑖𝑟𝑝𝑆𝑜𝑢𝑟𝑐𝑒 and 𝐴𝑛𝑡𝑒𝑛𝑛𝑎 𝐺𝑎𝑖𝑛𝑅𝑥 are defined in ETSI TR 103 108.
3.2
Results
The results of the analysis are illustrated below:
DA2GC AS Source - RLAN Victim
-80.0
-85.0
-90.0
-95.0
-100.0
-105.0
dBm/MHz -110.0
-115.0
-120.0
-125.0
-130.0
-135.0
-140.0
0
20
40
60
80
100
Range (km)
RLAN allowable interference
AS Interference (Indoor) - Altitude 10 kms
AS Interference RLAN (Outdoor) - Altitude 10 kms
AS Interference (Outdoor Directional) - Altitude 10 kms
Figure 5 : DA2GC AS Source (10km) / RLAN Victim
9
120
140
DA2GC AS Source - RLAN Victim
-80.0
-85.0
-90.0
-95.0
-100.0
-105.0
dBm/MHz -110.0
-115.0
-120.0
-125.0
-130.0
-135.0
-140.0
0
20
40
60
80
100
120
140
Range (km)
RLAN allowable interference
AS Interference (Indoor) - Altitude 3 kms
AS Interference RLAN (Outdoor Omni) - Altitude 3 kms
Figure 6 : DA2GC AS Source (3km) / RLAN Victim
It is concluded that the DA2GC AS would not cause interference to RLAN users for both indoor
and outdoor scenarios with the exception when an RLAN 18 dBi directional antenna is used.
However the probability of a directional antenna being used is low (0.1%) and the probability of
such an antenna pointing at the DA2GC AS is also low (6%). Hence the likelihood of such a
scenario is extremely low. Moreover the RLAN victim could select an alternative channel.
4 Compatibility between DA2GC GS (Victim) and RLAN (Source)
4.1
Methodology
4.1.1
Propagation
For terrestrial propagation pathloss the methodology adopted by ECC Reports 68 and 101 has
been used, namely:
𝜆
)
4𝜋𝑑
d ≤ d0
𝑃𝑎𝑡ℎ𝑙𝑜𝑠𝑠 = 20𝑙𝑜𝑔10 (
𝜆
𝑑
d0 ˂ d ≤ d1
𝑃𝑎𝑡ℎ𝑙𝑜𝑠𝑠 = 20𝑙𝑜𝑔10 (4ᴫ𝑑 ) − 10𝑛0 𝑙𝑜𝑔10 (𝑑 )
0
0
𝜆
𝑑
𝑑
𝑃𝑎𝑡ℎ𝑙𝑜𝑠𝑠 = 20𝑙𝑜𝑔10 (4ᴫ𝑑 ) − 10𝑛0 𝑙𝑜𝑔10 (𝑑1 ) − 10𝑛1 𝑙𝑜𝑔10 (𝑑 )
0
0
1
d ˃ d1
Urban
Breakpoint distance d0 (m)
64
Pathloss factor n0 beyond the first break point
3.8
Breakpoint distance d1 (m)
128
Pathloss factor n1 beyond the second breakpoint
Table 2: Propagation Parameters
10
4.3
All ground stations are planned to be sited in an urban environment to benefit from the existing
points of presence offered by the telecommunicatioins infrastructure
4.1.2
Unwanted Interference
The unwanted interference into the DA2GC GS has been calculated according to the following
equation:
𝐼𝑛𝑡𝑒𝑟𝑓𝑒𝑟𝑖𝑛𝑔 𝑆𝑖𝑔𝑛𝑎𝑙 = 𝐸𝑖𝑟𝑝𝑆𝑜𝑢𝑟𝑐𝑒 − 𝑊𝑎𝑙𝑙 − 𝐶𝑙𝑢𝑡𝑡𝑒𝑟 − 𝐿𝑜𝑠𝑠𝑃𝑟𝑜𝑝
−𝐿𝑜𝑠𝑠𝐷𝐴2𝐺𝐶 𝐺𝑆 𝐹𝑒𝑒𝑑𝑒𝑟 + 𝐴𝑛𝑡𝑒𝑛𝑛𝑎 𝐺𝑎𝑖𝑛𝐷𝐴2𝐺𝐶 𝐺𝑆
Where:
EirpSource : Eirp in dBm assuming 23 dBm Tx and 3 dBi antenna gain
Wall : Wall attenuation 15 dB for indoor case else 0 dB
Clutter : Clutter is dB according to SE44(13)118
For DA2GC, 𝐴𝑛𝑡𝑒𝑛𝑛𝑎 𝐺𝑎𝑖𝑛𝐷𝐴2𝐺𝐶 𝐺𝑆 is defined in ETSI TR 103 108.
4.2
Results
The results of the analysis are given below:
DA2GC GS Victim - RLAN Source
-100
-110
-120
dBm/MHz -130
-140
-150
-160
0.01
2.01
4.01
6.01
8.01
10.01
12.01
14.01
16.01
18.01
20.01
22.01
Distance (kms)
RLAN Interference (dBm/MHz) (Urban Outdoor)
RLAN Interference (dBm/MHz) (Rural Outdoor 20 MHz)
RLAN Interference (dBm/MHz) (Rural Indoor)
RLAN Interference (dBm/MHz) (Rural Outdoor 80 MHz)
RLAN Interference (dBm/MHz) (Rural Outdoor Directional 20 MHz)
RLAN Interference (dBm/MHz) (Rural Outdoor Directional 80 MHz)
DA2GC Threshold (dBm/MHz)
RLAN Interference (dBm/MHz) (Urban Indoor)
RLAN Interference (dBm/MHz) (Rural Outdoor 40 MHz)
RLAN Interference (dBm/MHz) (Rural Outdoor 160 MHz)
RLAN Interference (dBm/MHz) (Rural Outdoor Directional 40 MHz)
RLAN Interference (dBm/MHz) (Rural Outdoor Directional 160 MHz)
Figure 7 : DA2GC GS Victim / RLAN Source
It is concluded that there is essentially no unacceptable interference for the urban indoor case.
This will be the usual case given the DA2GC GS urban siting preference.
For the urban outdoor and rural indoor cases the minimum separation distance is about 100
metres. This again it not seen as a problem because the actual DA2GC GS antenna height will
normally be well above the RLAN antenna and its antenna cut-off at negative angles is more
pronounced than the Eirp mask suggests.
11
The rural outdoor scenario, using an omni antenna, could generate some interference at
distances less than 600 metres for a 20 MHz bandwidth and less than 300 metres for a 160
MHz bandwidth. However this could be mitigated by DA2GC GS site screening or the RLAN
selecting another channel because of DFS. Also the probability of a rural outdoor RLAN being
within 600 metres of the DA2GC GS is less than 0.1%.
For the rural outdoor scenario using a directional antenna the separation distance increases to
about 5 km. However the probability of this scenario ever occurring is extremely low given:



0.1% probability of a directional antenna being used
6% probability that a directional antenna is pointing at the DA2GC GS
5% probability that there will be a DA2GC GS in the RLAN cell
Overall it is considered that operational compatibility is achieved.
5 Compatibility between DA2GC GS (Source) and RLAN (Victim)
5.1
Methodology
5.1.1
Propagation
For terrestrial propagation pathloss the methodology adopted by ECC Reports 68 and 101 has
been used, namely:
𝜆
d ≤ d0
𝑃𝑎𝑡ℎ𝑙𝑜𝑠𝑠 = 20𝑙𝑜𝑔10 (4𝜋𝑑)
𝜆
)
4ᴫ𝑑0
− 10𝑛0 𝑙𝑜𝑔10 ( )
𝜆
)
4ᴫ𝑑0
− 10𝑛0 𝑙𝑜𝑔10 ( 1 ) − 10𝑛1 𝑙𝑜𝑔10 ( )
𝑃𝑎𝑡ℎ𝑙𝑜𝑠𝑠 = 20𝑙𝑜𝑔10 (
𝑃𝑎𝑡ℎ𝑙𝑜𝑠𝑠 = 20𝑙𝑜𝑔10 (
𝑑
𝑑0
d0 ˂ d ≤ d1
𝑑
𝑑0
𝑑
𝑑1
d ˃ d1
Urban
Breakpoint distance d0 (m)
64
Pathloss factor n0 beyond the first break point
3.8
Breakpoint distance d1 (m)
128
Pathloss factor n1 beyond the second breakpoint
4.3
Table 3: Propagation Parameters
All ground stations are planned to be sited in an urban environment to benefit from the existing
points of presence offered by the telecommunicatioins infrastructure
5.1.2
Unwanted Interference
The unwanted interference into the DA2GC GS has been calculated according to the following
equation:
𝐼𝑛𝑡𝑒𝑟𝑓𝑒𝑟𝑖𝑛𝑔 𝑆𝑖𝑔𝑛𝑎𝑙 = 𝐸𝑖𝑟𝑝𝑆𝑜𝑢𝑟𝑐𝑒 − 𝑊𝑎𝑙𝑙 − 𝐶𝑙𝑢𝑡𝑡𝑒𝑟 − 𝐿𝑜𝑠𝑠𝑃𝑟𝑜𝑝
+𝐴𝑛𝑡𝑒𝑛𝑛𝑎 𝐺𝑎𝑖𝑛𝑅𝐿𝐴𝑁
Where:
EirpSource : Eirp in dBm according to ETSI TR 103 108
Wall : Wall attenuation 15 dB for indoor case else 0 dB
Clutter : Clutter is dB according to SE44(13)118
12
Antenna GainRLAN : 3 dBi according to SE44(13)118.
5.2
Results
The results of the analysis are given below:
DA2GC GS Source - RLAN Victim
-80
-90
-100
dBm/MHz -110
-120
-130
-140
0.01
2.01
4.01
6.01
8.01
10.01
12.01
14.01
16.01
18.01
20.01
22.01
Distance (kms)
DA2GC Interference (dBm/MHz) (Urban Outdoor))
RLAN allowable interference (dBm/MHz)
DA2GC Interference (dBm/MHz) (Rural Outdoor Omni)
DA2GC Interference (dBm/MHz) (Urban Indoor)
DA2GC Interference (dBm/MHz) (Rural Indoor)
DA2GC Interference (dBm) (Rural Outdoor Directional)
Figure 8 : DA2GC GS Source / RLAN Victim
In conclusion, the separation distances to protect RLAN are less than 200 metres for three
scenarios. For the rural outdoor case with omni antenna the distance becomes about 800
metres but the probability of a rural outdoor RLAN being within 800 metres of the DA2GC GS is
less than 0.1%. However, it is noted that the preferred siting for DA2GC GSs is urban.
For the rural outdoor case with directional antenna the distance increases to about 11 km.
However, as discussed previously, this scenario is extremely unlikely. Nevertheless the RLAN
user could select an alternative channel.
Overall it is considered that operational compatibility is achieved.
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6 Conclusions
From the analyses undertaken it may be concluded that:



There would be no unacceptable interference between the DA2GC AS and deployed
RLANs.
Any interference between the DA2GC GS and indoor RLANs is unlikely because of
modest wall attenuations assumed.
For the outdoor RLAN case any interference is likely to be improbable given the
expected number of outdoor users. With the omni antenna mitigation is possible by
applying a minimum separation distance or for the RLAN to select an alternative
channel. Indeed DFS may initiate this automatically. With the directional antenna the
probability of interference low but mitigation can be introduced using site screening or
simply using an alternative RLAN channel.
The overall conclusion is that DA2GC and the proposed RLAN would be operationally
compatible because the probability of unacceptable interference is very low.
However, if any RLAN operation in the band 5855 MHz to 5875 MHz could be restricted to
indoor use then essentially there would be no unacceptable interference.
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