Owj101105 Wcdma Rnp Repeater Planning Issue1.1
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Transcript of Owj101105 Wcdma Rnp Repeater Planning Issue1.1
Wireless Curriculum Development SectionWireless Curriculum Development SectionWireless Curriculum Development SectionWireless Curriculum Development Section
ISSUEISSUE
OWJ101105 WCDMA RNP OWJ101105 WCDMA RNP Repeater PlanningRepeater Planning
OWJ101105 WCDMA RNP OWJ101105 WCDMA RNP Repeater PlanningRepeater Planning
1.11.1
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ReviewReview
repeaters are mainly used in areas where it is
difficult to extend the coverage, or used as a l
ow-cost solution for network construction.
This Slide first of all describes Repeater type
s and main parameters, and then discusses
Repeater application planning and analyses r
epeater application problems
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ObjectivesObjectives
Repeater types and main parameters.
How to plan the application of
Repeater.
How to analyze repeater application
problems.
Upon completion of this course,you will be able to:
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Course ContentsCourse Contents
Introduction
Repeater Types and Main Parameters
Repeater Application Planning
Analysis of Repeater Application Problems
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IntroductionIntroduction
Repeater has always been one of the methods to solve
special coverage in radio network applications.
Functionally it is an RF signal power amplifier. Repeaters
are used in microwave, GSM and CDMA system. In
general, repeaters are mainly used in areas where it is
difficult to extend the coverage, or used as a low-cost
solution for network construction.
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IntroductionIntroduction
An RF repeater system includes a donor antenna for communic
ation with the donor NodeB, a repeater for filtering and amplifyi
ng uplink and downlink signals and a service antenna for trans
mitting and receiving subscriber signals within repeater coverag
e area.
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IntroductionIntroduction
These slides mainly include three parts:
Repeater types and main parameters: repeater main types, base
working principle and main parameters.
Repeater application planning: major application occasions,
analysis of major characteristics, antenna selection and installation,
site selection, neighbor cell planning and handover planning.
Analysis of repeater application problems: influences on network,
location service, RRM algorithms and repeater co-existence with
other systems.
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Course ContentsCourse Contents
Introduction
Repeater Types and Main Parameters
Repeater Application Planning
Analysis of Repeater Application Problems
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Repeater Types and Main ParametersRepeater Types and Main Parameters
Based on the transmission link modes between NodeBs and repeate
rs, repeaters can be classified into the following two types:
RF repeater
Optical fiber repeater
Based on the working channel bandwidth, repeaters can be classifie
d into the following two types:
Wideband repeater
Frequency selection repeater
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Repeater Types and Main ParametersRepeater Types and Main Parameters
RF repeater basic working principle:
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Repeater Types and Main ParametersRepeater Types and Main Parameters
RF repeater characteristics: An RF repeater communicates with the donor NodeB through space
signal propagation, and no land transmission resources are
required;
There should be enough isolation between the donor antenna and
the service antenna, otherwise self-excitation will occur;
Due to the antenna isolation requirement, the rated maximum
transmit power is relatively low.
Avoid service antenna signals leaking into the donor antenna, a
directional antenna is usually adopted for outdoor coverage;
Signal around donor antenna should be relatively pure and stable
(line-of-sight transmission is satisfied and there is no big signal
fluctuation).
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Repeater Types and Main ParametersRepeater Types and Main Parameters
Fiber optical repeater basic working principle:
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Repeater Types and Main ParametersRepeater Types and Main Parameters
Fiber optical repeater characteristics:
An optical fiber repeater communicates with the donor NodeB via
optical fiber, so optical transmission resources are necessary;
An optical fiber repeater does not require antenna isolation;
The rated maximum transmit power of an optical fiber repeater is
relatively high
Directional antennas and omni antennas are both applicable to
optical fiber repeaters;
An optical fiber repeater implements unique selection of donor cell
signals and it can lead in dominant pilot signals to pilot pollution
areas.
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Repeater Types and Main ParametersRepeater Types and Main Parameters
List of parameters of wideband RF repeater:
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Repeater Types and Main ParametersRepeater Types and Main Parameters
Description of Major Parameters:
1. Maximum output power
The higher the output power of the repeater carrier frequency
is, the larger downlink capacity the repeater can provide.
Generally the maximum output power of an optical fiber
repeater is higher than that of an RF repeater.
2. Channel Bandwidth
The channel bandwidth of a WCDMA repeater is 1-2 carriers.
A repeater does not have to satisfy more carriers
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Repeater Types and Main ParametersRepeater Types and Main Parameters
Description of Major Parameters:
3. Repeater Processing Delay
The internal processing delay of a repeater should be as small
as possible because the delay will exert negative effects on
WCDMA location service performance. Among the repeater
parameters, the processing delay should be less than 5us.
4. Noise figure
Noise figure refers to the difference between the input signal-
to-noise ratio and the output signal-to-noise ratio. In general,
the noise figure of a WCDMA repeater should be less than
5dB.
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Repeater Types and Main ParametersRepeater Types and Main Parameters
Description of Major Parameters:
5. Characteristics of output spectrum
The output spectrum of a repeater should be close to the input
spectrum of a NodeB. If the output spectrum is not good
enough, the out-of-band suppression capability will be
insufficient. As a result, strong out-of-band emission will occur,
and thus interference will occur.
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Course ContentsCourse Contents
Introduction
Repeater Types and Main Parameters
Repeater Application Planning
Analysis of Repeater Application Problems
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Repeater Application PlanningRepeater Application Planning
Major Application Occasions of
Repeaters
Analysis of Major Characteristics
Repeater Antenna Selection and
Installation
Site Selection
Neighbor cell Planning
Repeater Handover Planning
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Repeater Application PlanningRepeater Application Planning
Major Application Occasions of Repeaters
To expand the service range and remove coverage dead
zones;
Sparsely-populated rural areas, small towns, small
residential areas, low-cost coverage solution;
Along highways, railroads and tunnels, to improve the
coverage efficiency of specific areas;
Urban indoor environments with high penetration loss;
To enhance the dominant cell signal in multi-pilot areas
to remove pilot pollution
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Repeater Application PlanningRepeater Application Planning
Major Application Occasions of
Repeaters
Analysis of Major Characteristics
Repeater Antenna Selection and
Installation
Site Selection
Neighbor cell Planning
Repeater Handover Planning
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Repeater Application PlanningRepeater Application Planning
Analysis of Noise Introduction by Repeaters
NodeB
TMA(opt)
Re
peate
r
G_AntBS
G_DonarRep
G_ServiceRep
G_RepDL&G_RepUL
L_ CableBS
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Repeater Application PlanningRepeater Application Planning
Analysis of Noise Introduction by Repeaters
Isolation between donor antennas and service antennasCL_RepDo-Ser
Path loss from the repeater to UEPLRep-UE
Path loss from the repeater to the donor NodeBDoPLBS-Rep
Noise figure of the service-end receiver of the repeaterNFRep
The downlink gain of the repeaterG_RepDL
The uplink gain of the repeaterG_RepUL
Gain of service antenna of the repeaterG_ServiceRep
Gain of donor antenna of the repeaterG_DonarRep
Feeder cable loss between the repeater and the service antennaL_CableSer-Rep
Feeder cable loss between the repeater and the donor antennaL_CableDo-Rep
The maximum uplink transmission power of the repeaterPmax_ULRep
The maximum downlink transmission power of the repeaterPmax_DLRep
The equivalent noise figure of the TTA port when a TTA is usedNFTMA
Noise figure of NodeB (top of cabinet)NFBS
NodeB antenna gainG_AntBS
Feeder cable loss from the top of cabinet to the antenna (when there is a TTA (tower top amplifier), it is the
feeder cable loss from the top of cabinet to the TTA port)L_CableBS
The maximum transmission power of NodeB (top of cabinet)PmaxBS
DescriptionSymbol
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Repeater Application PlanningRepeater Application Planning
The rise of NodeB noise figure when no TMA:
RepULRep__ BSDoCLGCLG
Where,
DoCLBS-Rep refers to the coupling loss between the antenna
connector of the NodeB and the top of cabinet on the donor side of
the repeater, and it equals to DoPLBS-Rep - G_AntBS - G_DonarRep +
L_CableDo-Rep.
BSBS
BSBSBS
BSBSBSBS
NFNFcableLCLG
NFNFcableLDoCLG
NFcableLDoCLGNFNFBSNF
Rep
RepRepUL
RepULRepRep
__1
_Rep_1
_Rep__
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Repeater Application PlanningRepeater Application Planning
Relationship between the rise of noise figure and (ΔG_CL - L_cableBS) wh
en NFBS =NFRep =3dB :
L_cableBS is an engineering parameter of the NodeB side, which is
unrelated to repeater installation. Therefore, when a repeater is used,
the increase of receiver floor noise of NodeB is determined by the
difference ΔG_CL (logarithm domain)
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Repeater Application PlanningRepeater Application Planning
The rise of NodeB noise figure when no TMA:
The bigger the ΔG_CL value is, accordingly the higher the uplink
gain of the corresponding repeater is or the smaller the coupling
loss between NodeB and repeater is, the bigger increase the floor
noise of the NodeB receiver will be.
ΔG_CL L_cableBS
Floor noise increase of
NodeB
3 dB 3 dB 3 dB
-3 dB 3 dB 1 dB
-6 dB 3 dB 0.5 dB
-13 dB 3 dB 0.1 dB
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Repeater Application PlanningRepeater Application Planning
The rise of NodeB noise figure when TMA:
DoCLBS-Rep refers to the coupling loss between the antenna
connector of the NodeB and the top of cabinet on the donor side of
the repeater, and it equals to DoPLBS-Rep - G_AntBS -G_DonarRep +
L_CableDo-Rep.
TMA
TMABS
TMABSTMA
NFNFCLG
NFNFDoCLG
NFDoCLGNFNFBSNF
Rep
RepRepUL
RepULRepRep
_1
Rep_1
Rep__
RepULRep__ BSDoCLGCLG
Where,
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Repeater Application PlanningRepeater Application Planning
The rise of NodeB noise figure when TMA:
Assume that the equivalent noise figure at the TTA port is also 3dB,
and the feeder cable loss between the TTA and the antenna can be
neglected
ΔG_CL Floor noise increase of NodeB
0 dB 3 dB
-6 dB 1 dB
-9 dB 0.5 dB
-16 dB 0.1 dB
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Repeater Application PlanningRepeater Application Planning
Repeater Reverse Gain Configuration:
if the floor noise increase of NodeB caused by a repeater want be
below 0.1dB, namely, the influence on the NodeB receiving
sensitivity is less than 0.1dB, ΔG_CL should be less than -16dB,
and the corresponding repeater uplink gain G_RepUL should be
16dB lower than the coupling loss DoCLBS-Rep between the NodeB
and the repeater.
G_RepUL < DoCLBS-Rep – 16dB
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Repeater Application PlanningRepeater Application Planning
Repeater Forward Gain Configuration:
Where, SENSUE and SENSBS are the receiving sensitivity of UE and
that of NodeB respectively.
PmaxBS – PmaxUE + G_RepDL - G_RepUL = SENSUE – SENSBS
Meanwhile,
GRep_DL < Pmax_DLRep – ( PmaxBS – DoPLBS-Rep)
Where, GRep_DL is the downlink gain of the repeater, Pmax_DLRep is
the maximum downlink transmit power of repeater, PmaxBS is the
maximum transmit power of the donor NodeB, and DoPLBS-Rep is the
coupling loss between repeater and NodeB.
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Repeater Application PlanningRepeater Application Planning
Isolation Requirements of Repeater:
Where, GRep is the repeater gain (in general, it is the uplink or
downlink gain value, whichever is bigger), and 15dB is the
protection margin.
GRep < Antenna Isolation – 15dB
The coupling loss between the donor antenna and the service
antenna of the repeater is called antenna isolation. If the repeater
amplification gain is greater than the antenna isolation, a positive
feedback loop will form among donor antenna->repeater->service
antenna->donor antenna, where signals are repeatedly amplified,
causing self-excitation and fault of the repeater.
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Repeater Application PlanningRepeater Application Planning
Horizontal Isolation Requirements of Repeater:
Where, d refers to the distance between the donor antenna and the
service antenna, in the unit of meter.
Gt and Gr refer to the gain in horizontal connection direction
between the two antennas, in the unit of dBi
AH = 22+20log(d /λ) – (Gt + Gr ) ( dB )
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Repeater Application PlanningRepeater Application Planning
Vertical Isolation Requirements of Repeater:
Where, g1 and g2 refer to the gain in the vertical connection
direction between the two antennas, in the unit of dBi. For specific
values, refer to the antenna parameters. In general, g1=g2=0dBi.
Av = 28+40log(d/λ) - (g1+g2) (dB)
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Repeater Application PlanningRepeater Application Planning
Barrier isolation of obstacles :
Install two sets of antennas on different walls of buildings, so as to
realize isolation by means of the walls; where we cannot realize
barrier isolation by means of the building, for example, when the
antennas are installed on the top of an iron tower, we can install
shielding net for isolation
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Repeater Application PlanningRepeater Application Planning
Major Application Occasions of
Repeaters
Analysis of Major Characteristics
Repeater Antenna Selection and
Installation
Site Selection
Neighbor cell Planning
Repeater Handover Planning
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Repeater Antenna Selection and InstallationRepeater Antenna Selection and Installation
– Select suitable antenna gain based on the specific signal condition and coverage requirement;
– Omni antennas cannot be adopted; otherwise self-excitation will occur. Antennas with high gains and narrow horizontal beams are most suitable. In general, angle-reflection antennas or log.-per. antennas are adopted to avoid introduction of unnecessary pilot signals;
– The antenna of the donor sector in the donor NodeB can adopt a cross polarization mode different from that of other sectors and the NodeBs, so that the repeater can select the pilot from the donor sector efficiently.
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Repeater Antenna Selection and InstallationRepeater Antenna Selection and Installation
– The service antenna should be selected based on different characteristics of the coverage area. If the antenna needs to cover a large area, a directional antenna for common NodeBs can be used, but the antenna must have a high gain; for tunnel coverage, we can select a Yagi antenna or a helical antenna; for indoor coverage, a specially designed indoor antenna is usually required.
– Antenna pattern: During antenna installation, the zero point of one set of antenna’s pattern should be directed to the other antenna. In general, the antennas are installed back-to-back. In this case, it is very important to select antennas with high front-to-rear ratio (over 30dB).
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Repeater Antenna Selection and InstallationRepeater Antenna Selection and Installation
– Vertical isolation: The lobes of the repeater antennas are usually narrow in the vertical direction. When the service antenna and the donor antenna are vertically installed, the zero points of their vertical patterns should be directed to each other, so good antenna isolation can be obtained .
– Environment factors: The environment around the antennas may influence antenna isolation. The environment factors include: the existence of reflectors near the front side of the antennas, the material of the tower, and the existence of shielding objects or shielding net between the donor antenna and the service antenna.
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Repeater Application PlanningRepeater Application Planning
Major Application Occasions of
Repeaters
Analysis of Major Characteristics
Repeater Antenna Selection and
Installation
Site Selection
Neighbor cell Planning
Repeater Handover Planning
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Site SelectionSite Selection
For an optical fiber repeater
– Optical fibers should be available from the site to the donor NodeB.
– The transmission delay between the site and the donor NodeB should meet the requirement, which depends on the support of the optical fiber repeater to the distance.
– The repeater site should meet the same antenna and feeder deployment requirement as for a common NodeB.
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Site SelectionSite Selection
For an RF repeater – In order to avoid big fluctuations of electric wave
propagation loss between the repeater and the donor NodeB, the site should meet the requirements for line-of-sight transmission between the repeater and the donor NodeB;
– The site should reach the receiving signal level required for the repeater equipment (-50dBm ~ -80dBm in general).
– There should be no strong same frequency carrier wave near the donor antenna except the donor NodeB, so as to prevent the repeater from amplifying signals from multiple cells.
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Site SelectionSite Selection
For an RF repeater
– The landform, building or iron tower that can provide enough isolation between the donor antenna and the service antenna is available.
– In order to avoid increased probability of hard handovers, a repeater site where the carrier quantity of the donor NodeB is equal to that of the NodeBs adjacent to the repeater.
– Preferably, there should be no other interferences nearby.
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Site SelectionSite Selection
The repeater site should be between the donor NodeB and the dead
zone. Make sure that the azimuth angle between the donor antenna
and the service antenna is not smaller than 90°
Correct sites Incorrect sites
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Site SelectionSite Selection
Avoid selecting places facing front side of buildings, the signals hav
e attenuated seriously and the signal strength in the back areas is r
ather weak. If the repeater site is selected at the side of buildings, si
gnals can provide better coverage with the help of reflection.
Correct sites Incorrect sites
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Site SelectionSite Selection
In special cases, restricted by various factors, the donor links
cannot ensure the line of sight. In such cases, a received signal
level test must be conducted to make sure that the electric wave
propagation of donor links is stable.
Carry out propagation forecast and system balance calculations
based on the survey result and determine relevant parameters
of the repeater, such as the minimum receiving level of the
donor antenna, repeater gain, the service antenna type and the
type and length of the feeder cable.
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Repeater Application PlanningRepeater Application Planning
Major Application Occasions of
Repeaters
Analysis of Major Characteristics
Repeater Antenna Selection and
Installation
Site Selection
Neighbor Cell Planning
Repeater Handover Planning
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Neighbor cell PlanningNeighbor cell Planning
In a network with repeaters, neighbor cell planning should f
ollow the principles of the planning for the common Node
Bs. A repeater and the existing donor sector are regarded
as the same sector, so the neighbor cell relationships of a
repeater are set in the existing donor sector. And vice ver
sa, if there is any NodeB adjacent to a repeater, the neigh
bor cell relationships of the repeater’s donor sector shoul
d be included in that NodeB.
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Repeater Application PlanningRepeater Application Planning
Major Application Occasions of
Repeaters
Analysis of Major Characteristics
Repeater Antenna Selection and
Installation
Site Selection
Neighbor cell Planning
Repeater Handover Planning
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Repeater Handover PlanningRepeater Handover Planning
When selecting the handover type, consider the
performance differences among softer handover, soft
handover and hard handover. We should first consider
softer handover, and then soft handover. Consider hard
handover only in special cases.
As repeaters provide coverage extension, they are
generally located at the edge of the network, where hard
handover is like to take place. If hard handover exists,
we should set the hard handover parameters to make
sure of that hard handover can be implemented timely
and efficiently.
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Course ContentsCourse Contents
Introduction
Repeater Types and Main Parameters
Repeater Application Planning
Analysis of Repeater Application Problems
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Analysis of Repeater Application ProblemsAnalysis of Repeater Application Problems
Influences on Network
Influences on Location service
Influences on RRM Algorithms
Repeater Co-existence
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Influences on NetworkInfluences on Network
1. Cell coverage influences
Thermal noise exists in the receiver of a repeater, so thermal n
oise will be added in the signals amplified by the repeater. As
a result, the noise level of the donor NodeB increases, the sen
sitivity of the donor NodeB receiver decreases and the covera
ge radius of the donor cell is reduced.
When a repeater is added in an existing network, do not place
it at the existing coverage edge of the donor cell, but a margin
should be provided to avoid the coverage absence between th
e repeater and the donor NodeB.
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Influences on NetworkInfluences on Network
A repeater can only forward signals from the donor NodeB, so
it cannot provide new capacity. However, because the use of
a repeater extend the coverage range of the entire sector, the
extension of the subscriber distribution range will accordingly l
ead to the increase of the required power and the growth of th
e number of subscribers.
Because a repeater casts influences on the floor noise of the
donor NodeB, the reverse link will need more power. As a res
ult, the interference will increase, and the capacity is accordin
gly reduced.
2. Analysis of capacity influences
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Influences on NetworkInfluences on Network
As a bi-directional amplifier, a repeater can distinguish only
different frequencies, but not different scrambling code. If
multiple cell signals with the same frequency of the donor cell
signals exist around the donor antenna, an RF repeater will be
unable to distinguish them and it will forward the signals from
multiple cells to the to-be-covered area, resulting in pilot
pollution. Thus the network quality is influenced.
To avoid pilot pollution, when selecting the site of an RF
repeater, make sure that no signals from multiple cells exist
around the donor antenna. In addition, select an antenna with
high gain and narrow horizontal beam as the donor antenna.
In addition, optical fiber repeater should be used.
3. Pilot pollution
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Influences on NetworkInfluences on Network
For an RF repeater, if the repeater gain is greater than the
isolation between the donor antenna and the service antenna, a
positive feedback loop of signals will form among donor antenna -
> repeater -> service antenna -> donor antenna, resulting in self-
excitation.
To avoid self-excitation, make sure that the gain setting of an RF
repeater meets the antenna isolation requirement. In addition,
make sure that the antenna isolation of an RF repeater meets the
requirement when selecting the repeater site and installing
antennas.
4. Repeater self-excitation
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Analysis of Repeater Application ProblemsAnalysis of Repeater Application Problems
Influences on Network
Influences on Location service
Influences on RRM Algorithms
Repeater Co-existence
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Influences on Location serviceInfluences on Location service
In an OTDOA-based LCS, a UE performs location estimation by
measuring the arrival time of multiple (more than 3) UTRA CPICH
s. After a repeater is introduced, the arrival time of NodeB downli
nk signals will seriously lag, so the performance of OTDOA locati
on method will deteriorate.
(1) For small cells (5us delay corresponds to 1.5km), signals from re
peaters can be identified and eliminated if signals with too high d
elay.
(2) If a UE detects signals from over 3 NodeBs at the same time, the
signals with too high delay compared with those from other Node
Bs can be eliminated.
1. OTDOA
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Influences on Location serviceInfluences on Location service
When repeaters are used, the coverage areas of cells will
change, and therefore the location precision will be worse.
2. CELL-ID
3. A-GPS
When a repeater is used, the influence on the A-GPS location
method includes two aspects: the influence brought by frequency
drift of the repeater and the influence brought by the extra
propagation delay. Of these two aspects, the influence brought
by frequency drift is relatively smaller (frequency stability of the
repeater: 0.01ppm), and it can be neglected.
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Analysis of Repeater Application ProblemsAnalysis of Repeater Application Problems
Influences on Network
Influences on Location service
Influences on RRM Algorithms
Repeater Co-existence
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Influences on RRM Algorithms Influences on RRM Algorithms
(1)Repeater power restriction has influences on the
algorithms.
(2) When a repeater is used, change of parameters will affect
the algorithms (for example Eb/N0).
A repeater brings in new noise when amplifying and
forwarding signals, causing deterioration of the signal
quality. When a repeater is used, the uplink and downlink
Eb/N0 should be increased correspondingly.
(3) When a repeater is used, change of the original network
topological planning influences algorithms
Influences on RRM algorithms are as follows:
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Influences on RRM Algorithms Influences on RRM Algorithms
(1) Power control algorithm
(2) Admission control algorithm
(3) Congestion control algorithm
(4) Load balance algorithm
(5) Potential user control algorithm
Repeater may influence the following PRM algorithms:
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Influences on RRM Algorithms Influences on RRM Algorithms
(1)The requirement of line-of-sight transmission between the
donor antenna and the donor NodeB should be satisfied
(2) Strictly limit the application range of repeaters, it can be
used only within low-traffic coverage restricted areas.
(3) Close some algorithms for cells using repeaters (inter-
frequency load balance algorithm, potential user control
algorithm, and so on).
Corresponding solutions :
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63
Analysis of Repeater Application ProblemsAnalysis of Repeater Application Problems
Influences on Network
Influences on Location service
Influences on RRM Algorithms
Repeater Co-existence
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Repeater Co-existence Repeater Co-existence
The isolation between the donor antenna of repeater A of
operator A and the antenna of NodeB B of operator B must meet
the following requirement:
Uplink without considering repeater spurious
CLBSB-RepA SsIR_Target + ACGRepA – CLminRepA-UEA + CLBSB-UEB
Uplink without considering repeater spurious
PmaxRepA 39dBm, CLBSB-RepA 105dB;
39dBm > PmaxRepA 31dBm, CLBSB-RepA PmaxRepA + 66dB;
PmaxRepA < 31dBm, CLBSB-RepA 97dB.
Co-existence with UTRA FDD :
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Repeater Co-existence Repeater Co-existence
CLBSB-RepA refers to the isolation between repeater A and NodeB B,
SsIR_Target refers to the interference level to NodeB B after
repeater A is put into use (the interference level is defined as
strength of signal from UEB received by NodeB B / strength of
signal from UEB of RepA received by NodeB B),
ACGRepA refers to the adjacent channel gain of repeater A,
CLminRepA-UEA refers to the minimum coupling loss between
repeater A and UEA (In general, CLminRepA-UEA is equal to
CLminRepA-UEB ),
and CLBSB-UEB refers to the coupling loss between UEB (UE at the
place where the coupling loss of repeater A is minimum) and
NodeB B.
Co-existence with UTRA FDD :
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Repeater Co-existence Repeater Co-existence
For example
The measured minimum coupling loss between UEB and RepA is
70dB, and the measured coupling loss between UE and NodeB B
is 100dB. The repeater out-of-band gain ACGRepA is 53dB.
SsIR_Target is set as 0dB.
To make sure the system of operator B works stably, the minimum
coupling loss between the repeater donor port and NodeB B must
be:
CLBSB-RepA = SsIR_Target + ACGRepA - CLminRepA-UEA + CLBSB-UEB =
0dB + 53dB - 70dB +100dB = 83dB
Co-existence with UTRA FDD :
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67
Repeater Co-existence Repeater Co-existence
The isolation between the donor antenna of repeater A
of operator A and the antenna of NodeB B of operator
B must meet the following requirement:
Downlink
The isolation between the service antenna and the
NodeB antenna should be greater than 30dB, as
described in 3GCP TS 25.106.
Co-existence with UTRA FDD :
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68
Repeater Co-existence Repeater Co-existence
When an UTRA FDD repeater share the same site with a
TDD NodeB, the isolation between the service antenna and
the NodeB antenna should be greater than 30dB. For the
donor antenna, the isolation requirement is the same as for
the case of site sharing with an FDD NodeB.
Co-existence with UTRA TDD :
Co-existence with GSM 900 and/or DCS 1800 :
The isolation between the service antenna or the
donor antenna and the GSM or DCS antenna should
be greater than 30dB .
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69