GSM-R compatibility measurements BNetzA

Transcription

GSM-R compatibility measurements BNetzA
CG-GSM-R(13)033
Compatibility measurements
UMTS/LTE/GSM -> GSM-R
Thomas Hasenpusch
Federal Network Agency, Germany
www.bundesnetzagentur.de
Motivation / Aims

Frequency planning in Europe:
downlink
uplink
E-GSM-R
GSM-R
E-GSM-R
E-GSM-R
876
921
Public mobile networks
873 880

GSM-R
890
Public mobile networks
918 925
915
935
960
What happens to the GSM-R terminal receivers when
facing UMTS/LTE in the public mobile band above
925 MHz?
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
2
Interference Mechanisms (1)
Unwanted emissions from UMTS/LTE in the GSM-R
channel

A
925 MHz
f
GSM-R
channel
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
3
Interference Mechanisms (2)
Receiver blocking due to high input powers

A
Max. mixer power
Min. S/N
f
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
4
Interference Mechanisms (3)

Receiver intermodulation (2 narrowband signals)
A
GSM-R
channel
f
fIM

f1
f2
fIM = 2*f1-f2
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
5
Interference Mechanisms (4)

Receiver intermodulation (1 wideband signal)
924.8MHz
UMTS
921.2MHz
GSM
UMTS signal
IM products (all)
IM frequencies involved when GSM-R frequency is 921.2 MHz
IM frequencies involved when GSM-R frequency is 924.8 MHz
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
6
Interfering GSM Signals
GSM spectrum
0,0 dB
"GSM standard" signal
-10,0 dB
"GSM realistic" signal
Spectrum mask ETSI TS 145 005 Table 4.2.1.3-a2
-20,0 dB
-30,0 dB
-40,0 dB
-50,0 dB
-60,0 dB
-70,0 dB
-80,0 dB
-90,0 dB
-100,0 dB
920,2
MHz
920,7
MHz
921,2
MHz
921,7
MHz
922,2
MHz
GSM-R compatibility measurements (BnetzA Germany)
922,7
MHz
923,2
MHz
923,7
MHz
924,2
MHz
924,7
MHz
925,2
MHz
01.08.2017
7
Interfering UMTS signals
UMTS spectrum
0 dB
-10 dB
-20 dB
"UMTS standard" signal
"UMTS realistic" signal
Spectrum mask ETSI TS 125 104 V10.0 Table 6.3
Spectrum mask realistic signal
-30 dB
-40 dB
-50 dB
-60 dB
-70 dB
-80 dB
917,5
MHz
918,5
MHz
919,5
MHz
920,5
MHz
921,5
MHz
GSM-R compatibility measurements (BnetzA Germany)
922,5
MHz
923,5
MHz
924,5
MHz
925,5
MHz
926,5
MHz
927,5
MHz
01.08.2017
8
Interfering LTE/5MHz signals
LTE spectrum
0 dB
"LTE standard" signal
"LTE realistic" signal
-10 dB
Spectrum mask ETSI TS 136 141 V10.5.0 Table 6.6.3.5.2.2-1
Spectrum mask realistic signal
-20 dB
-30 dB
-40 dB
-50 dB
-60 dB
-70 dB
-80 dB
917,5
MHz
918,5
MHz
919,5
MHz
920,5
MHz
921,5
MHz
GSM-R compatibility measurements (BnetzA Germany)
922,5
MHz
923,5
MHz
924,5
MHz
925,5
MHz
926,5
MHz
927,5
MHz
01.08.2017
9
Receiver Selection

Rx1 „improved“: Receiver with highly linear frontend, improved filter and AGC, exceeding
requirements of ETSI TS 102 933

Rx2 „standard“: Receiver representing equipment
currently used in trains, meeting requirements of
ETSI EN 300 910 V8.5.1 and ETSI TS 145 005 V8.16
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
10
Failure Criterion

The GSM-R link was regarded interfered when the
RxQual value reported by the terminal receiver
dropped to 4 or less.

Measured with CMU200 base station tester.
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
11
Measurement of Receiver Characteristics

Sensitivity of both receivers: -107 to -108 dBm

Selectivity (measured with unmodulated carrier):
Rx rejection
0 dB
-10 dB
-20 dB
Rx1 (improved) at 924.8 MHz
-30 dB
Rx1 (improved) at 923.0 MHz
-40 dB
Rx2 (standard) at 924.8 MHz
Rx2 (standard) at 923.0 MHz
-50 dB
-60 dB
-70 dB
-80 dB
-90 dB
-100 dB
-110 dB
-4000 kHz
-3000 kHz
-2000 kHz
-1000 kHz
GSM-R compatibility measurements (BnetzA Germany)
0 kHz
1000 kHz
2000 kHz
3000 kHz
4000 kHz
01.08.2017
12
C/I from Unwanted Emissions

Measurement setup:
Rx
uplink
10 dB
GSM-R base
station
emulator
CMU200
Tx
(10)
M
GSM-R
receiver
(DUT)
downlink
Interfering
signal
Signal
generator
6-60 dB

Circulator
50 dB
20 dB
Directional
coupler
GSM-R signal level: -101 dBm and -98 dBm
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
13
C/I from Unwanted Emissions
Measurement results for standard interferers:

Standard interfering signals -> GSM-R: Protectio ratios due to unwanted emissions
10 dB
GSM
0 dB
theoretical C/I for GSM
UMTS
theoretical C/I for UMTS
-10 dB
LTE/5MHz
-20 dB
theoretical C/I for LTE/5MHz
C/I
-30 dB
-40 dB
-50 dB
-60 dB
-70 dB
-80 dB
924,8 MHz
926,8 MHz
928,8 MHz
930,8 MHz
interfering frequency
GSM-R compatibility measurements (BnetzA Germany)
932,8 MHz
934,8 MHz
01.08.2017
14
C/I from Unwanted Emissions
Measurement results for realistic interferers:

Realistic interfering signals -> GSM-R: Protectio ratios due to unwanted emissions
10 dB
GSM (standard receiver)
GSM (improved receiver)
theoretical C/I for GSM
UMTS
theoretical C/I for UMTS
LTE/5MHz
theoretical C/I for LTE/5MHz
0 dB
-10 dB
-20 dB
-30 dB
C/I
-40 dB
-50 dB
-60 dB
-70 dB
-80 dB
-90 dB
-100 dB
924,8 MHz
926,8 MHz
928,8 MHz
930,8 MHz
interfering frequency
GSM-R compatibility measurements (BnetzA Germany)
932,8 MHz
934,8 MHz
01.08.2017
15
C/I Using Blocking Test Setup:

Measurement setup:
Rx
GSM-R base
station
emulator
CMU200
uplink
10 dB
Circulator
M
Tx
downlink
Interfering
signal
Band pass
6-60 dB
50 dB
GSM-R
receiver
(DUT)
20 dB
Directional
coupler
Signal
generator

GSM-R frequencies 924.8 MHz and 921.2 MHz

GSM-R signal levels between -101 and -35 dBm

3 different interfering frequencies, but always high offset
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
16
C/I Using Blocking Test Setup
Measurement results for GSM interferer:

Blocking scenario: GSM-R = 921.2 MHz, GSM on 925.2 MHz
Rx1 (improved)
10 dBm
Rx2 (standard), first occurrence
interfering level
Rx2 (standard), second occurrence
0 dBm
-10 dBm
-20 dBm
-30 dBm
-110 dBm
-100 dBm
-90 dBm
-80 dBm
-70 dBm
wanted level
GSM-R compatibility measurements (BnetzA Germany)
-60 dBm
-50 dBm
-40 dBm
01.08.2017
17
C/I Using Blocking Test Setup
Measurement results for broadband interferer:

Blocking scenario: GSM-R = 924.8 MHz, LTE/5MHz on 957.5 MHz
interfering level
10 dBm
0 dBm
-10 dBm
-20 dBm
Rx1 (improved)
Rx2 (standard)
-30 dBm
-110
-100
-90
GSM-R compatibility measurements (BnetzA Germany)
-80
-70
wanted level
-60
-50
-40
01.08.2017
18
C/I Using Intermodulation Test Setup

Measurement setup:
Rx
uplink
10 dB
GSM-R base
station
emulator
CMU200
Tx
Circulator
(10)
M
GSM-R
receiver
(DUT)
downlink
Interfering
signal
Band pass
6-60 dB
+
50 dB
20 dB
Directional
coupler
50
Ω
Signal
generator 1
Signal
generator 2
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
19
C/I Using Intermodulation Test Setup

Frequency combinations:
Signal 1
Signal 2
Combination
System
Frequency f1
System
Frequency f2
1
GSM
935,0 MHz
GSM
948,8 MHz
2
GSM
935,0 MHz
UMTS
947,5 MHz
3
UMTS
937,5 MHz
GSM
953,8 MHz
4
LTE/10MHz
935,0 MHz
UMTS
942,5 MHz
5
UMTS
937,5 MHz
UMTS
952,5 MHz
6
GSM
927,4 MHz
UMTS
932,5 MHz
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
20
C/I Using Intermodulation Test Setup

Measurement results
Rx2 (standard): Intermodulation Scenarios
0 dBm
GSM on 935.0MHz - GSM on 948.8MHz
GSM on 935.0MHz - UMTS on 947.5MHz
-10 dBm
UMTS on 937.5MHz - GSM on 953.8MHz
LTE/10MHz on 935MHz - UMTS on 942.5MHz
UMTS on 937.5MHz - UMTS on 952.5MHz
interfering level
GSM on 927.4MHz - UMTS on 932.5MHz
-20 dBm
-30 dBm
-40 dBm
-50 dBm
-100 dBm
-90 dBm
-80 dBm
-70 dBm
wanted level
GSM-R compatibility measurements (BnetzA Germany)
-60 dBm
-50 dBm
01.08.2017
21
Combination of Results
One single GSM interferer

Protectio ratio for one GSM interferer at different wanted signal levels
10 dB
0 dB
= Rx1
= Rx2
-10 dB
-20 dB
-40dBm
-30 dB
C/I
-40 dB
-60dBm
-50 dB
-60dBm
-60dBm
-60 dB
-70 dB
-80dBm
-90dBm
-80dBm
-90dBm
-80 dB
standard signal
-80dBm
-90dBm
-100dBm
-100dBm
-100 dBm
-90 dB
realistic signal
-100 dB
-110 dB
<= -60dBm
-120 dB
0 MHz
2 MHz
4 MHz
6 MHz
frequency separation
GSM-R compatibility measurements (BnetzA Germany)
8 MHz
10 MHz
01.08.2017
22
Combination of Results

One UMTS interferer:
Protectio ratio for one UMTS interferer at different wanted signal levels
10 dB
0 dB
-10 dB
= Rx1
-20 dB
= Rx2
-30 dB
-60dBm
C/I
-40 dB
-50 dB
standard signal
-60 dB
-80dBm
-60dBm
-70 dB
realistic signal
-80 dB
-90dBm
-100dBm
-80dBm
-100 dBm
<= -60dBm
-90 dB
-100 dB
-110 dB
-120 dB
0 MHz
1 MHz
2 MHz
3 MHz
4 MHz
5 MHz
6 MHz
frequency separation
GSM-R compatibility measurements (BnetzA Germany)
7 MHz
8 MHz
9 MHz
01.08.2017
10 MHz
23
Combination of Results
One LTE/5MHz interferer:

Protectio ratio for one LTE/5MHz interferer at different wanted signal levels
10 dB
0 dB
-10 dB
= Rx1
-20 dB
= Rx2
-30 dB
C/I
-40 dB
-70dBm
standard signal
-50 dB
-80dBm
-90dBm
-60 dB
-70 dB
-60dBm
-70dBm
-80dBm
-80 dB
-100 dBm
realistic signal
-100dBm
<= -60dBm
-90 dB
-100 dB
-110 dB
-120 dB
0 MHz
1 MHz
2 MHz
3 MHz
4 MHz
5 MHz
6 MHz
frequency separation
GSM-R compatibility measurements (BnetzA Germany)
7 MHz
8 MHz
9 MHz
01.08.2017
10 MHz
24
Combination of Results

Two or more GSM interferers:
Protectio ratio for a pure GSM interferer scenario
10 dB
= Rx1
0 dB
= Rx2
public m obile band
-10 dB
-20 dB
-50dBm
-30 dB
-65dBm
C/I
-40 dB
-80dBm
-50 dB
-90dBm
-98 dBm
-60 dB
standard signal
-70 dB
realistic signal
-80 dB
-80dBm
-90dBm
-98dBm
-90 dB
-100 dB
0,0 MHz
0,4 MHz
0,8 MHz
1,2 MHz
1,6 MHz
2,0 MHz
2,4 MHz
2,8 MHz
frequency separation to closest interferer (centre)
GSM-R compatibility measurements (BnetzA Germany)
3,2 MHz
3,6 MHz
01.08.2017
25
Combination of Results

UMTS interferer plus UMTS/GSM interferer:
Protectio ratio for a UMTS/GSM and UMTS/UMTS interferer scenario
10 dB
0 dB
public m obile band
= Rx2
-10 dB
-20 dB
-50dBm
-40 dB
-65dBm
C/I
-30 dB
standard signal
-50 dB
-80dBm
-60 dB
-90dBm
-98dBm
-70 dB
realistic signal
-80 dB
-90 dB
-100 dB
0 MHz
1 MHz
2 MHz
3 MHz
4 MHz
5 MHz
6 MHz
frequency separation to closest interferer (centre)
GSM-R compatibility measurements (BnetzA Germany)
7 MHz
01.08.2017
8 MHz
26
Result Evaluation (1)

At low GSM-R levels unwanted emissions dominate, at
higher GSM-R levels receiver overloading dominates.

Transition between interference effects strongly depends
on interfering signal quality: Realistic signals have much
less interference potential from unwanted emissions than
signals just meeting the standard.

The interference potential of UMTS and LTE/5MHz is nearly
equal.

Interference potential due to unwanted emissions from
UMTS/LTE is about 10-20 dB higher than from GSM.

One UMTS/LTE signal alone may create receiver
intermodulation often affecting the whole GSM-R band.
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
27
Additional Measurements with Filters


Necessary to assess:

GSM-R on upper channels, UMTS/LTE in first 5MHz of
public band (critical situations)

Improvements by different receiver filter solutions
Receiver configurations:

Rx1: „improved“

Rx2: „standard“

Rx3: „standard“ receiver plus dual 8-cavity Kaelus filter

Rx4: „improved“ receiver
plus small Lorch filter
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
28
Additional Measurements with Filters

Filter response dual 8-cavity Kaelus (1):
Ref
1
0
0 dBm
TG
Att
0 dBm
30 dB
RBW 300 kHz
VBW 3 MHz
SWT 100 ms
Marker 1 [T1 ]
-3.07
925.000000000
Marker 3 [T1 ]
-44.49
926.300000000
-10
1 RM*
CLRWR
Marker 2 [T1 ]
-61.33 dBm
925.580000000 MHz
-20
dBm
MHz
A
dBm
MHz
-30
-40
3
PRN
-50
-60
3DB
2
-70
-80
-90
-100
Start 925 MHz
1 MHz/
GSM-R compatibility measurements (BnetzA Germany)
Stop 935 MHz
01.08.2017
29
Additional Measurements with Filters

Filter response dual 8-cavity Kaelus (2):
Ref
0 dBm
0
TG
Att
0 dBm
30 dB
1
2
RBW 1 MHz
VBW 10 MHz
SWT 100 ms
Marker 3 [T1 ]
-65.61 dBm
934.000000000 MHz
Marker 1 [T1 ]
-1.95
923.000000000
Marker 2 [T1 ]
-2.92
925.000000000
-10
1 RM*
CLRWR
-20
dBm
MHz
A
dBm
MHz
-30
-40
PRN
-50
3DB
-60
3
-70
-80
-90
-100
Center 925 MHz
5 MHz/
GSM-R compatibility measurements (BnetzA Germany)
Span 50 MHz
01.08.2017
30
Additional Measurements with Filters

Filter response low pass Lorch (1):
Ref
2
0
0 dBm
TG
Att
RBW 300 kHz
VBW 3 MHz
SWT 100 ms
0 dBm
30 dB
Marker 2 [T1 ]
-2.68 dBm
925.000000000 MHz
Marker 1 [T1 ]
-58.26 dBm
930.000000000 MHz
-10
A
1 RM*
CLRWR -20
-30
-40
PRN
-50
1
3DB
-60
-70
-80
-90
-100
Start 925 MHz
1 MHz/
GSM-R compatibility measurements (BnetzA Germany)
Stop 935 MHz
01.08.2017
31
Additional Measurements with Filters

Filter response low pass Lorch (2):
Ref
2
0
0 dBm
TG
Att
0 dBm
30 dB
1
RBW 1 MHz
VBW 10 MHz
SWT 100 ms
-10
1 RM *
CLRWR -20
Marker 3 [T1 ]
-62.20 dBm
941.500000000 MHz
Marker 1 [T1 ]
-2.57
925.000000000
Marker 2 [T1 ]
-1.54
900.900000000
dBm
MHz
A
dBm
MHz
-30
-40
PRN
-50
3DB
3
-60
-70
-80
-90
-100
Center 925 MHz
5 MHz/
GSM-R compatibility measurements (BnetzA Germany)
Span 50 MHz
01.08.2017
32
Additional Measurements with Filters

Measurement setup:
Rx
uplink
10 dB
GSM-R base
station
emulator
Tx
CMU200
Signal
generator
SMU200A
Circulator
(10)
M
downlink
Interfering
signal
50 dB
GSM-R
receiver (DUT)
incl. filter for
Rx3 and Rx4
20 dB
Directional
coupler

GSM-R frequencies 924.8 MHz and 924.2 MHz

GSM-R levels from -101 dBm to -31 dBm

Interfering frequencies 927.6 MHz and 932.6 MHz (UMTS/LTE)
and 925.2 MHz (GSM)
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
33
Additional Measurements with Filters

Result example (realistic broadband interferer):
GSM-R = 924.8 MHz, LTE/5MHz realistic on 927.6 MHz
-10 dB
Rx1 (improved)
Rx2 (standard)
-20 dB
Rx3 (standard) with Kaelus filter
Rx4 (improved) with Lorch filter
protection ratio
-30 dB
-40 dB
-50 dB
-60 dB
-70 dB
-110 dBm
-100 dBm
-90 dBm
-80 dBm
-70 dBm
wanted level
GSM-R compatibility measurements (BnetzA Germany)
-60 dBm
-50 dBm
-40 dBm
01.08.2017
34
Additional Measurements with Filters

Result example (standard broadband interferer):
GSM-R = 924.8 MHz, LTE/5MHz standard on 927.6 MHz
-10 dB
Rx1 (improved)
-20 dB
Rx2 (standard)
Rx3 (standard) with Kaelus filter
Rx4 (improved) with Lorch filter
protection ratio
-30 dB
-40 dB
-50 dB
-60 dB
-70 dB
-110 dBm
-100 dBm
-90 dBm
-80 dBm
-70 dBm
-60 dBm
-50 dBm
-40 dBm
wanted level
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
35
Additional Measurements with Filters

Result example (realistic interferer on 932.6 MHz):
GSM-R = 924.8 MHz, UMTS realistic on 932.6 MHz
-10 dB
Rx1 (improved)
-20 dB
Rx2 (standard)
Rx3 (standard) with Kaelus filter
protection ratio
-30 dB
-40 dB
-50 dB
-60 dB
-70 dB
-110 dBm
-100 dBm
-90 dBm
-80 dBm
-70 dBm
-60 dBm
-50 dBm
-40 dBm
wanted level
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
36
Additional Measurements with Filters

Result example (standard interferer on 932.6 MHz):
GSM-R = 924.8 MHz, UMTS standard on 932.6 MHz
-10 dB
Rx1 (improved)
-20 dB
Rx2 (standard)
Rx3 (standard) with Kaelus filter
protection ratio
-30 dB
-40 dB
-50 dB
-60 dB
-70 dB
-110 dBm
-100 dBm
-90 dBm
-80 dBm
-70 dBm
-60 dBm
-50 dBm
-40 dBm
wanted level
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
37
Additional Measurements with Filters
Result example (realistic interferer vs. channel 970):

GSM-R = 924.2 MHz, UMTS realistic on 927.6 MHz
-10 dB
Rx1 (improved)
-20 dB
Rx3 (standard) with Kaelus filter
protection ratio
-30 dB
-40 dB
-50 dB
-60 dB
-70 dB
-110 dBm
-100 dBm
-90 dBm
-80 dBm
-70 dBm
-60 dBm
-50 dBm
-40 dBm
wanted level
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
38
Additional Measurements with Filters

Result example (standard interferer vs. channel 970):
GSM-R = 924.2 MHz, UMTS standard on 927.6 MHz
-10 dB
Rx1 (improved)
-20 dB
Rx3 (standard) with Kaelus filter
protection ratio
-30 dB
-40 dB
-50 dB
-60 dB
-70 dB
-110 dBm
-100 dBm
-90 dBm
-80 dBm
-70 dBm
-60 dBm
-50 dBm
-40 dBm
wanted level
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
39
Additional Measurements with Filters

Result example (GSM realistic interferer):
GSM-R = 924.8 MHz, GSM realistic on 925.2 MHz
-10 dB
Rx1 (improved)
Rx2 (standard)
-20 dB
Rx3 (standard) with Kaelus filter
Rx4 (improved) with Lorch filter
protection ratio
-30 dB
-40 dB
-50 dB
-60 dB
-70 dB
-110 dBm
-100 dBm
-90 dBm
-80 dBm
-70 dBm
wanted level
GSM-R compatibility measurements (BnetzA Germany)
-60 dBm
-50 dBm
-40 dBm
01.08.2017
40
Additional Measurements with Filters

Transition levels from unwanted emissions to overloading effects
Interferer
Rx1
Rx2
(improved)
Rx3
(standard)
Rx4
(standard with
Kaelus filter)
(improved with
Lorch filter)
UMTS realistic on
927.6 MHz
-80 dBm
-100 dBm
never *)
-80 dBm
LTE realistic on
927.6 MHz
-85 dBm
-98 dBm
never *)
-85 dBm
UMTS standard on -48 dBm
927.6 MHz
-72 dBm
never *)
-45 dBm
LTE standard on
927.6 MHz
-52 dBm
-78 dBm
never *)
-50 dBm
UMTS realistic on
932.6 MHz
never *)
-100 dBm
never *)
-
LTE realistic
on 932.6 MHz
never *)
-100 dBm
never *)
-
UMTS standard on never *)
932.6 MHz
-85 dBm
never *)
-
LTE standard on
932.6 MHz
never *)
-90 dBm
never *)
-
GSM realistic on
925.2 MHz
-90 dBm
-80 dBm
-80 dBm
-88 dBm
GSM standard on
925.2 MHz
-85 dBm
-75 dBm
-72 dBm
-82 dBm
GSM-R compatibility measurements (BnetzA Germany)
*) never = not overloaded up to about +10 dBm
01.08.2017
41
Result Evaluation (2)

The standard receiver is nearly always overloaded by
UMTS/LTE in the first 5 MHz of the public mobile band.

The improved receiver is only overloaded when UMTS/LTE
is on 927.6 MHz and the GSM-R level is high (>80dBm for
realistic, >50dBm for standard signals), and then the
tolerable interference level is up to 20 dB higher than for
the standard receiver.

Receivers with the Kaelus filter are never overloaded by
UMTS/LTE signals.

The additional Lorch filter for the improved receiver does
not further increase immunity against UMTS/LTE on
927.6 MHz.
GSM-R compatibility measurements (BnetzA Germany)
01.08.2017
42
Compatibility measurements
UMTS/LTE/GSM -> GSM-R
Thank you for your attention!
Thomas Hasenpusch
Federal Network Agency, Germany / ECC
www.bundesnetzagentur.de

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