05%2e umts co 2dlocation issue
TRANSCRIPT
7/29/2019 05%2E UMTS Co 2Dlocation Issue
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UMTS Co-location Issues
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• Introduction
• Interference Analysis Methodology
• Interference Analysis Results
• UMTS operators co-existence
• Interference Prevention
— Antenna protection
— Filter(s)
• PHS interference issues
• Conclusion
Agenda
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• UMTS comes after other radio systems
— CDMA (800, 900, 1900), GSM900, GSM1800, GSM1900
• High data rate & multi-service UMTS networks require a
high density of sites
• It becomes more and more difficult to find new sites:
—UMTS market pressure
– Available radio sites are very limited
– Quick rollout & cost reduction
—Environment protection
Introduction
Radio site sharing is one of the efficient solution
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• Introduction
• Interference Analysis Methodology
• Interference Analysis Results
• UMTS operators co-existence
• Interference Prevention
— Antenna protection
— Filter(s)
• PHS interference issues
• Conclusion
Agenda
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Interference Analysis Methodology
Spurious emissions and
intermodulationsstudy
Blocking study
Required isolationbetween GSM / UMTS
antenna connector
and UMTS antenna
connector
Antennas performances BTS performances
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• Introduction
• Interference Analysis Methodology
• Interference Analysis Results
• UMTS operators co-existence
• Interference Prevention
— Antenna protection
— Filter(s)
• PHS interference issues
• Conclusion
Agenda
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Required isolationsbased on
standard recommendations
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Standard recommendationsRequired isolations
UMTStransmitter
to
GSM 900
receiver
GSM 900transmitter
to UMTS
receiver
UMTStransmitter
to
GSM 1800
receiver
GSM 1800transmitter
to UMTS
receiver
UMTStransmitter
to
UMTS
receiver
Blocking 40 dB 58 dB 48 dB 58 dB 63 dB
Spurious
emissionsIntermodu
lations
products
29 dB
83 dB
(32 dBwith New
Req)
29 dB
83 dB
(32 dBwith New
Req)
32 dB
: required isolations are pessimistic since no feeder losses have been taken into account
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Required isolationsbased on
products performances
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Physical calculations considering UMTScompetitor BTS and Nortel UMTS iBTSRequired isolations
iBTS UMTS
transmitter to
iBTS UMTS
receiver
iBTS UMTS
transmitter to
UMTS competitor
receiver
UMTS competitor
transmitter to
iBTS UMTS
receiver
Blocking 0 dB 63 dB 0 dB
Spurious
emissions
Intermodu
lations products
15 dB 15 dB 32 dB
: required isolations are pessimistic since no feeder losses have been taken into account
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Physical calculations considering GSMcompetitor BTS and Nortel UMTS iBTSRequired isolations
: required isolations are pessimistic since no feeder losses have been taken into account
iBTS UMTS Tx to GSM
Rx
GSM Tx to iBTS UMTS
Rx
Blocking 40 dB(GSM 900)
48 dB(GSM 1800)
28 dB
Spurious
frequencies 14 dB
83 dB
(32 dB if compliant withnew GSM req.)
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Conclusion
• Nortel iBTS UMTS:
— iBTS UMTS has better performances than the UMTS
standard recommendation
• Competitor BTS:
— If only compliant with standard recommendations,
interference problems will occur
Important to do studies considering the real
performances of the products
in order to reduce the required isolations to avoid
interference between systems
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• Introduction
• Interference Analysis Methodology
• Interference Analysis Results
• UMTS operators co-existence
• Interference Prevention
— Antenna protection
— Filter(s)
• PHS interference issues
• Conclusion
Agenda
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UMTS operators co-existenceUL Interference Mechanism
• Adjacent channel interference— a single mobile can have severe impact on a large number of other
mobiles
— "cell breathing" phenomenon
In Tx-UMTS Channel, MS side
Associated in Rx-UMTS Channel, BS side
1920 MHZ 1980 MHZ
UMTS FDD UL band
Capacity loss
Possible dead zones
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UMTS operators co- existenceDL Interference Mechanism•
Adjacent channel interference:— Smaller impact:
– Design of the BS
– Fewer users affected
In Tx-UMTS Channel, BS side
Associated in Rx-UMTS Channel, UE side
2110 MHZ 2170 MHZ
UMTS FDD DL band
Possible dead zones
Capacity loss
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UMTS operators co- existenceACP
ACLR
ACS
Ability of a transmitter to
confine its transmissions to
its own channel
Ability of a receiver to
exclude theinterference present
on an adjacent
channel
ACP
Sums up the degree of interaction
between adjacent channels. Combination
of both transmitter and receiver
performance
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UMTS operators co-existenceSolutions
Carrier spacing
Good ACLR
Co-location
SOLUTIONS
Good ACP / ACIR
Good ACS
Adjacent Channel
Leakage Ratio Adjacent Channel Selectivity
Adjacent Channel
Protection /
Adjacent Channel
Interference Ratio
Spectrum efficiency
Equipment limitations .
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UMTS operators co- existenceSome values of ACP from Normalisation & Nortel ACP
• Agreement between participant on the following values
of ACLR (25.101, 25.104) for FDD mode:
• The UE has less ACP due to its small size.
ACLR1
(5 MHz)
ACLR2
(10 MHz)MS 33 dB 43 dB
BS 45 dB 50 dB
Nortel ACLR & ACS = 58 dB
ACLR & ACS
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UMTS operators co-existenceCarrier spacing
•
For UMTS, allocated bandwidth for one carrier is 5 MHz andspacing between central frequency is 5 MHz
— With this spacing between two adjacent competitor channels (and assumingthe standard required ACP), the capacity loss is around 5%
• Idea: decrease the distance between two carriers belonging to thesame operator in order to move away from competitor’s carrier toget more protection
— 4.6 MHz spacing (intra operator) => ACP decrease of around 10 dB
— 5.4 MHz spacing (inter operator) => ACP increase of 2 dB
• Spacing of 4.8 MHz (instead of 5 MHz) between two carriers
belonging to the same operator is a good choice:— No impact on capacity (intra operator)
— Reducing the capacity loss (inter operator)
• Carrier spacing performance is linked to the design of filter
Carrier spacing
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UMTS operators co-existenceCo-location• Co-location means less UL adjacent channel interference due to UE
and less DL adjacent channel interference due to BS:
• But, inter BS interferences can occur:
Co-location
System B
System A
BS filterings
can reduce these
interferences
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2020
UMTS operators co-existenceConclusion
• UMTS operators coexistence consequences:
— Capacity loss
— Dead zones
• Solutions:
— High ACP
— Carrier spacing:
–
At least 5 MHz between two inter-operator FDD –
FDD carriers – At least 4.8 MHz between two intra-operator FDD – FDD
carriers
— FDD – FDD base stations co-location
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• Introduction
• Interference Analysis Methodology
• Interference Analysis Results
• UMTS operators co-existence
• Interference Prevention
— Antenna protection
—Filter(s)
• PHS interference issues
• Conclusion
Agenda
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Co-siting radio solutions
Wideband
Noise
Spurious
emissionsIntermodulations
Blocking
Co-siting solutions
BTS radio
performances
Filters
BTS antennaAntenna decoupling
Antenna isolation
Antenna rejection
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Main solutions
• Antenna protection
• External filter(s)
— External filter at Tx BTS sidefor reducing Tx out-bandspurious and widebandnoise transmission
— External filter at Rx BTS
side for protecting out-bandof Rx band and improvingthe Rx blocking performance
Interference Prevention
System A
BTS
System
B BTS
Antenna
decoupling
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Main Solutions With antenna decoupling, required additional decoupling (dB) is
Requ ire isolat ion (dB ) – Rx cable loss (dB ) – Tx cable loss
- An tenna decoupl ing (dB)
If addit ional decoup l ing 0 OK !
If addit ional decoup l ing > 0 Filter(s) are needed !
Interference Prevention
System A System B
PA
Combiner
PA
Combiner
RxLev RxLev
Decoupling
Cable Loss Cable Loss
TxPATxPA
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Interference Prevention
Antenna protection
• Antenna separation decoupling : – attenuation between two antennas when
separated (between the two connectors) for a
given frequency band
– depends on antenna performances and site
configuration
• Antenna rejection :
– attenuation of a signal fed into an antenna
working in another band
•Antenna isolation : – Attenuation of a signal between the
transmitting antenna connector and the
reception antenna connector
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Antenna decoupling
Two separated antennasVertical separation between antennas
• 1 mast per sector
• 1 UMTS antenna
• 1 antenna of other system
• Isolation is reached:
— by vertical separation between antennas
other BTS
UMTS
iBTS
Antenna
decoupling
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Antenna decoupling
Two separated antennasHorizontal separation between antennas
• 2 masts per sector
• 1 UMTS antenna
• 1 antenna of other system
• Isolation is reached:
—by horizontal separation between antennas
other BTS
UMTS
iBTS
Antenna
decoupling
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Antenna decoupling
Two separated antennas
example
• 1 X-polar antenna of other system
— 2 ports
• 1 UMTS X-polar antenna
— 2 ports
• 4 feeders per sector
Other systemUMTS
BTS
UMTS
Feeder
Cables
Other
BTS
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Antenna decoupling
Antenna 2
Antenna 1
Signal
generator Input
S
S’
Network analyser
Antenna decoupling measurement
between GSM 900/1800 X-
polar directives antennas and
UMTS X-polar directive
antenna
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with horizontal separation
0.5 to 4m
Antenna decoupling
d
GSM X -polar antenna
UMTS X -polar antenna
Average S' in UMTS band =0 deg
-90 -80 -70 -60 -50 -40 -30 -20 -10
0
0 1 2 3 4
Horizontal distance in m
S ' i n
d B
GSM-900 antenna
GSM-1800 antenna
Dual (GSM-900)
Dual (GSM-1800)
Average S' in UMTS band =60 deg
-100 -90 -80 -70 -60 -50 -40 -30 -20 -10
0
0 1 2 3 4
Horizontal distance in m
S ' i n
d B
GSM-900 antenna
GSM-1800 antenna Dual (GSM-900)
Dual (GSM-1800)
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Antenna decoupling
d dB
GSMX-polar antenna
UMTSX-polar antenna
Antenna decoupling versus
horizontal separation betweenantennas
• Antenna GSM 900
—d = 0.5 m = 65 dB
—
d = 3 m = 76 dB
• Antenna GSM 1800
—d = 0.5 m = 57 dB
—d = 3 m = 68 dB
• Antenna GSM dual band 900 / 1800
—d = 0.5 m = 62 dB (Tx 900) / 55dB (Tx 1800)
—d = 3 m = 75 dB (Tx 900) / 67 dB(Tx 1800)
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• Antenna decoupling with vertical separation
Antenna decoupling
D
UMTS
X-polar antenna
GSM X-polar antenna Average S' in UMTS band
Same azimut
-100.00
-90.00
-80.00
-70.00
-60.00
-50.00
-40.00
-30.00
-20.00
-10.00
0.00
0 0.5 1 1.5 2 2.5 3 3.5
Vertical distance in m
S ' i n
d B
GSM-900 antenna
GSM-1800 antenna
DUAL (GSM-900)
DUAL (GSM-1800)
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D
dB
UMTSX-polar antenna
GSMX-polar antenna
Antenna decoupling versus
vertical separation between
antennas
• Antenna GSM 900
—
D = 0.5 m
= 72 dB — D = 3 m = 81 dB
• Antenna GSM 1800
— D = 0.5 m = 54 dB
— D = 3 m = 65 dB
• Antenna GSM dual band 900 / 1800
— D = 0.5 m = 65 dB (Tx 900) / 60 dB(Tx 1800)
— D = 3 m = 70 dB (Tx 900) / 66 dB (Tx1800)
Antenna decoupling
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Antenna decoupling with Horizontal/vertical separation
Antenna decoupling
UMTSX-polar antenna
GSMX-polar antenna
D
d
Average S' in UMTS band
d=1.5m
Same azimut
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
0 0.5 1 1.5 2 2.5 3 3.5 4
Horizontal distance in m
S ' i n
d B
GSM-900 antenna
GSM-1800 antenna
Dual (GSM-900)
Dual (GSM-1800)
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Antenna decoupling
Antenna decoupling versus
vertical and horizontalseparations between antennas
• Antenna GSM 900
—d = 0.5 m = 70 dB
—d = 3 m = 85 dB
• Antenna GSM 1800
—d = 0.5 m = 60 dB
—d = 3 m = 71 dB
• Antenna GSM dual band 900 / 1800
—d = 0.5 m = 70 dB (Tx 900) / 60 dB
(Tx 1800)
—d = 3 m = 75 dB (Tx 900) / 72 dB
(Tx 1800)
UMTSX-polar antenna
GSMX-polar antenna
D
d
D = 1.5 m
Antenna decoupling versus azimuth
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Antenna decoupling versus azimuthdivergence between antennas
• Horizontal separation
with azimuth divergence
• Vertical separation with
azimuth divergence
d
GSM
Antenna
UMTS
Antenna
d
UMTS
Antenna
GSM
Antenna
d = 0.5 m
= 30°
d = 0.5 m = 90°
55 to 60 dB (1800)
65 to 70 dB (900)
60 dB (1800)
70 dB (900)
Antenna decoupling between two UMTS
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Antenna decoupling between two UMTSantennas versus horizontal or verticalseparation
• Vertical separation: • Horizontal separation:
75 dB D
dB
UMTS X-polar antenna
UMTSX-polar antenna
d dB
UMTSX-polar antenna
UMTS
X -polar antenna
d = 0.5 m
d = 0.5 m 55 dB
d = 3 m 70 dB 85 dB
d = 3 m
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Interference Prevention
• If antenna protection does not bring enough
isolation, filters can be added
— two separated antennas, physical separation and possible
filters
—one single antenna: dual band antenna, filters
—diplexer / triplexer whatever the type of antenna
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Example: two separated antennas -
Vertical separation• 1 mast per sector
• 1 UMTS antenna
• 1 GSM antenna
• Isolation is reached:— by vertical separation between antenna
— with filter at GSM side if antenna decoupling isnot sufficient
GSM Nortel
BTS
UMTS
iBTS
Antenna
decoupling
Co-location solutions example
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Co-location solutions example
Example: Two separated antennas
Horizontal (and/or vertical)
separation(s) between antennas
• 2 masts per sector
• 1 UMTS antenna & GSM antenna
• Isolation is reached:
— by vertical and horizontal separations between
antennas
— with filter at GSM side if antenna decoupling is
not sufficient
GSM Nortel
BTS
UMTS
iBTS
Antenna
decoupling
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Co-location solutions example
GSM Nortel
BTS
UMTSiBTS
Example: One single dualband antenna
• 1 mast per sector
• 1 GSM / UMTS dual band antenna
•
Isolation depends on antennaisolation between GSM and UMTSbands
— dual band antenna characterised byabout 30 dB of isolation between thedifferent bands
— filter at GSM side may be necessary
30 dB (typical value)
between GSM band
and UMTS band
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Example : Use of diplexer or
triplexer
• 1 mast per sector
• Isolation is reached with diplexer or
triplexer, which corresponds to actually
two or three filters:
— filter(s) at GSM side
— filter at UMTS side
• Whatever the type of antennas
— Wideband antenna
— dual band antenna / Triband antenna
— Monoband antenna
GSM Nortel
BTS
UMTS
iBTS
Diplexer
Co-location solutions example
Antennas options
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Antennas options
• 2 vertical antennas for each band
— 4 antennas per sector
—
Space diversity
• 2 vertical dual band antennas
— 2 antennas per sector
— Heavier antenna
— Space diversity
• 1 dual band cross polar antenna — 1 antenna per sector
— Cross polar diversity
• 1 cross polar antenna for each band
— 2 antennas per sector
— Cross polar diversity
• Measurements and simulations show that Xpolar diversity (0.7 correlationfactor) give a very good Eb/N0 gain. 1 antenna / sector is more suitable for Urban environments. 1.5 dB insertion loss
Dual Band antennas can be used on ly
i f equ ipped w ith independent electr ical
t i l t systems .
Feeders options
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p• Independent feeders /
independent antennas
• Shared feeders /
Shared antenna
DCS1800
BTS
UMTSiBTS
Duplexer Duplexer
Duplexer Duplexer
X-polar
Dual Bandantenna
• Shared feeders /
Independent antennas
DCS
1800
BTS
UMTSiBTS
X-polar
UMTSantenna
DCS1800
BTS
UMTSiBTS
Duplexer Duplexer
Duplexer Duplexer
• No reuse of 2G aerials
• New Feeders for UMTS
• New antenna for UMTS
• Site capacity ??
• Reuse of 2G feeders
• New antenna for UMTS
• Need additional feeder if
2G without diversity
• Reuse of 2G feeder
• Reuse of 2G antenna if X-
polar. Or 1 single new
antenna for both systems
Shared feeders using external Duplexer
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Shared feeders using external Duplexer
• Physical implementation (without diversity)
External
duplexer
Option al Cabin et area
for Low er duplexer shared
feeder
The external duplexer can be
associated with TTLNA (Tower Top
Low Noise Amplifier) for UMTS only
or for both UMTS and DCS 1800
Typical insertion loss for both
internal and external duplexer :0.5 dB. No impact on Link Budget
GSM 1800 path UMTS path
Frequency 1710 to 1880 MHz 1920 to 2170 MHz
Insertion loss (dB) 0.5 0.5
Return loss antenna port (dB) 18 18
Attenuation in GSM 50 50
Attenuation in UMTS 50
IMD 3rd order (dBc) -160 -160
Max Tx Power (W) 200 200
Duplexers provide necessary f i l ter ing
(isolat ion) between UMTS and GSM
Use of TTLNA (Tower Top Low Noise Amplifier)
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( p p )
• The TTLNA is used to increase the coverage of the cell by compensating
the feeder loss.
• It can be incorporated with the external duplexer, and provided only for
the UMTS path or for both paths.
DCS
1800
BTS
UMTS
iBTS
Duplexer Duplexer
X-polar
Dual Band
antenna
Duplexer
TTLNA
Duplexer
TTLNA
The impact on the Link
Budget is a 3 dB
increase of the reverse
path loss. Thiscorresponds to the
compensation of the
feeder loss. DCS
1800
BTS
UMTS
iBTS
X-polar
UMTS
antenna
TTLNATTLNA
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• Introduction
• Interference Analysis Methodology
• Interference Analysis Results
• UMTS operators co-existence
• Interference Prevention
— Antenna protection
—
Filter(s)
• PHS interference issues
• Conclusion
Agenda
C l ti b t PHS d UMTS
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Co-location between PHS and UMTSBase Stations• Wideband noise
— The frequency separation between the PHS band ([1905~1915MHz]) and theUMTS Uplink band ([1920~1980MHz]) is very small
— PHS maximum power corresponds to wideband noise of -22 dBm for a 5 Mhzband
— Required isolation is 96 dB
• Spurious emission
— PHS out of band spurious emission required to be less than 2.5 W –
correspond to a -26 dBm threshold in 5 Mhz UMTS band— PHS in band spurious emission required to be less than 250 nW – correspond to
a -36 dBm threshold in 5 Mhz UMTS band
— Required out of band isolation is 92 dB, required in band isolation is 16 dB
• Blocking
— PHS base station maximum transmit power is 2 W – correspond to 33 dBm
— Required isolation is 48 dB
Solution
• 50 dB out of band filtering at PHS base station output and physicalseparation of antennas
: required isolations are pessimistic since no feeder losses have been taken into account
PHS B St ti I t f i ith UMTS
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PHS Base Stations Interfering with UMTSMobiles• Wideband noise
— The frequency separation between the PHS band ([1905~1915MHz]) and the UMTSDownlink band ([2110~2170MHz]) is large enough
• Spurious emission— For out of band spurious, maximum tolerated interference level at the mobile side in the
UMTS band is –116.5 dBm
— For in band spurious, the minimum requirement gives a maximum power for the adjacentchannel interfering signal on receive at the UMTS mobile of –52 dBm
— Required out of band isolation is 90.5 dB, required in band isolation is 16 dB
• Blocking— The required blocking level for Downlink band in UMTS is –15 dBm
— Required isolation is 25 dB
Solution
• PHS signal has high pathloss, usually providing enough isolation• Additional isolation is required only in the worst case scenario when
PHS base station is very close to an UMTS mobile but far from thePHS mobile
: required isolations are pessimistic since no feeder losses have been taken into account
PHS M bil I t f i ith UMTS
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PHS Mobile Interfering with UMTSInfrastructure• Wideband noise and Spurious emission
— PHS specifications for base station and terminal are the same except maximum transmitpower
— Wideband noise and spurious emission discussion above remains the same
— Worst case isolation required is 96 dB
• Blocking— The required blocking level for Downlink band in UMTS is 10 dBm
—
Required isolation is 25 dBSolution
• PHS signal has high pathloss, usually providing enough isolation
• Additional isolation is required only in the worst case scenario whenPHS terminal is very close to an UMTS base station. Presumably theprobability is low.
: required isolations are pessimistic since no feeder losses have been taken into account
PHS M bil I t f i ith UMTS M bil
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PHS Mobile Interfering with UMTS Mobile
• Wideband noise and Spurious emission— PHS specifications for base station and terminal are the same except maximum transmit
power
— Wideband noise and spurious emission discussion above remains the same
— Worst case isolation required is 90.5 dB
• Blocking
— Required isolation is 25 dB
Solution
• PHS signal has high pathloss, usually providing enough isolation
• Additional isolation is required only in the worst case scenario whenPHS terminal is very close to an UMTS terminal. Presumably theprobability is low.
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•UMTS is an interference limited system—The interference must be minimized in the network design phase
in order to optimize coverage and Capacity
• Radio sites co-location brings interference
• Co-location solutions exist—BTS performance (Tx/Rx filters)
—Antenna decoupling with space separation (H/V)
—Antenna isolation with multi-band antenna
—External filters at BTS sides (Tx BP filter and Rx BP filter)
Conclusions
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