Wcdma planning

Company Confidential
LinkBudget Overview
Noise figure
Cable losses
Soft handover
gain,
antenna gain
Building Penetration
loss
Body loss
M
argin
s
PATH
LOSS
(L)
Max Allowed
Path Loss
(L)
= Tx Signal + All Gains – Other Losses – Rx
Sensitivity

Eb/N0
• In order to meet the defined quality requirements (BLER) a
certain average bit-energy divided by total noise+interference
spectral density (Eb/N0) is needed. Nokia simulations for Eb/No
are based on ITU recommendations.
• Eb is the received energy per bit from the wanted user,
• Io is the total received power density, from both interference
and thermal noise, excluding the power of the wanted signal.
• Eb/No depends on:
• Service
• MS speed
• Radio channel
Service Eb/No UL Eb/No DL
Voice 12.2 kbit/s, 3km/h 4 6,5
RT 14kbit/s, 3km/h 4 6,5
RT 64kbit/s, 3km/h 2 5,5
NRT 144kbit/s, 3km/h 1,2 4,8
NRT 384kbit/s, 3km/h 1 4,5

Required Eb/N0
[ ]dB
R
W
I
p
N
E rxb
⋅=
0
NothownDL PIII ++−= )1( α
NothownUL PIII ++=
Where:
Prx = received power
R = bit rate
W = bandwidth
Iown = total power received from the serving cell (excluding own signal)
Ioth = total power received from other cells
PN = noise power
α = orthogonality factor

Required Ec/I0
• Required Ec/I0 is the required RF C/I needed in order to
meet the baseband Eb/N0 criteria
• Ec/I0 independs on a bit rate
[ ]dB
I
p
W
R
N
E
I
E rxbc
=⋅=
00
Energy
per chip
Total power
spectral density

Processing Gain
Eb/No= + 4 dB Processing
Gain
Voice 12.2 kbps
Noise level (ex. -105 dBm)
RT 64 kbps
- 21 dB
- 16 dB
NRT 384 kbps
Eb/No= + 2 dB
-9 dB
Eb/No= + 1 dB
+25 dB
+18 dB
+10 dB
RequiredSignalPower
because of the processing gain
the spread signal can be
below the thermal noise level
[ ] SF
R
W
B
B
dBG
Baerer
U
p
u
===

Interference Margin
Interference margin is calculated from the UL/DL loading (η)
values. This parameter shows in DL how much the BTS
"sensitivity" is decreased due to the network load
(subscribers in the network) & in UL indicates the loss in
link budget due to load ( ) [ ]dBLog η−⋅− 110 10IMargin =
20
10
6
1.25
3
25% 50% 75% 99%
IMargin [dB]
Load factor η

Soft HandoverMDC Gain
• In DL there is some combining gain (about 1dB) due to
MS maximal ratio combining
• soft and softer handovers included
• from MS point there is no difference between soft and
softer handover
• average is calculated over all the connections taking into account
the average difference of the received signal branches (and MS
speed)
• 40% of the connections in soft handover or in softer
handover and 60% no soft handover
• taking into account the effect multiple transmitters (meaning the
receiver MS will get 3dB more power)
• combination of dynamic simulator results and static planning tool
• in case more than 2 connections - no more gain (compared to
case of two branches)

Slow and Fast Fading
• Fast Fading
Different Signal Path interfere and affect the received signal
• Rice Fading the dominant (usualy LOS) path exist–
• Rayleigt Fading no dominant path exist–

Slow and Fast Fading
• Slow Fading (Log-normal Fading)
In the real enviroment the propagation condition of the
electromagnetic wave are not stable. Some location and time
dependant variation in a signal strength appear when the mobile moves
around (shadowing effect). The variation of the signal strength are
normal distibuted on the logarithmical scale.
received signal level [dBm]
probability density
σ
σ [dB] has to be
measured
m
( )







 −
−⋅
⋅
= 2
2
2
exp
2
1
)(
σσπ
mx
xf

Soft HandoverGain
(Gain Against Slow Fading)
• Soft handover gain is the gain against shadow fading. This is
roughly the gain of a handover algorithm, in which the best
BTS can always be chosen (based on minimal transmission power
of MS) against a hard handover algorithm based on geometrical
distance.
• In reality the SHO gain is a function of required coverage
probability and the standard deviation of the signal for the
environment.
• The gain is also dependent on whether the user is outdoors,
where the likelihood of multiple servers is high, or indoors where
the radio channel tends to be dominated by a much smaller
number of serving cells.
• For indoors users the recommendation is to use smaller SHO gain value.

PowerControl Headroom
(Fast Fading Margin)
Power control headroom is the parameter to describe the
margin against fast fading. This parameter is needed
because at the cell edge the mobile does not have enough
power to follow the fast fading dips. This is especially
important for the slow moving mobiles
Power Control Headroom = (average required Ec/I0) without fast PC - (average required Ec/I0)
with fast PC
Source: Radio Network Planning & Optimisation for UMTS; J. Laiho, A. Wacker, T.
Novosad; Tab. 4.5
without fast PC with fast PC
5Hz 13,1 4,9 8,2
20Hz 11,5 5,7 5,8
40Hz 9,7 6,0 3,7
100Hz 7,9 6,0 1,9
240Hz 6,5 6,3 0,2
average requierd Ec/Io [dB]
max Doppler fr.
Power Control
Headroom
Channel:
Pedestrian A;
antenna diversity
assumed

Bit rate bit/s 64000 a
Total TX power available dBm 21 b
TX antenna gain dBi 2 c
Body loss dB 0 d
TX EIRP per traffic channel dBm 23 e=b+c-d
RX antenna gain dBi 18 f
RX cable and connector losses dB 3 g
Receiver noise figure dB 3 h
Thermal noise density dBm/Hz -174 j
Cell loading % 70 k
Noise rise due to interference dB 5.23 l=10*log10(1/(1-(k/100)))
Total effect of noise dBm/Hz -171 m=h+j
Information rate dBHz 48.06 n=db(a)
Effective required Eb/No dB 2.54 o
RX sensitivity dBm -115.40 p=l+m+n+o+correction factor
Soft Handoff Gain dB 4.5 q
Fast fading Margin dB 2.5 r
Log normal fade margin dB 11.6 s
In-building penetration loss (urban) dB 20 t
Maximum path loss urban dB 123.80 pl=e+f+q-g-p-r-s-t
UplinkBudget
Service
Bit Rate
Max. UE power
Tx antenna gain,
e.g. 2dBi for a
dipole
Attenuation due to
body obstruction.
Rx antenna gain
in the boresight
directionCable and connector
losses between the Rx
antenna and the
cabinet
Source thermal
noise
Loading
converted to
noise riseLoading in the cell due
to other users
Added system
noise
Bit rate
converted to dB
+
Attenuation
through building
walls
Effective Isotropic
Powerfromthe Tx
antenna

Bit rate bit/s 64000 a
Total TX power available dBm 21 b
TX antenna gain dBi 2 c
Body loss dB 0 d
TX EIRP per traffic channel dBm 23 e=b+c-d
RX antenna gain dBi 18 f
RX cable and connector losses dB 3 g
Receiver noise figure dB 3 h
Thermal noise density dBm/Hz -174 j
Cell loading % 70 k
Noise rise due to interference dB 5.23 l=10*log10(1/(1-(k/100)))
Total effect of noise dBm/Hz -171 m=h+j
Information rate dBHz 48.06 n=db(a)
Effective required Eb/No dB 2.54 o
RX sensitivity dBm -115.40 p=l+m+n+o+correction factor
Soft Handoff Gain dB 4.5 q
Fast fading Margin dB 2.5 r
Log normal fade margin dB 11.6 s
In-building penetration loss (urban) dB 20 t
Maximum path loss urban dB 123.80 pl=e+f+q-g-p-r-s-t
Path loss = Tx signal + all gains - losses - ( SNR + Noise)

UL & DL LinkBudget Calculations
Link budget
Chip rate 3840,00 DL data rate 64,00
UL Data rate 64,00 DL load 85%
UL Load 50%
2
Uplink Downlink
RECEIVING END Node B UE
Thermal Noise Density dBm/Hz -173,98 -173,98
Receiver Noise Figure dB 3,00 8,00
Receiver Noise Density dBm/Hz -170,98 -165,98
Noise Power [NoW] dBm -105,14 -100,14
Reguired Eb/No dB 2,00 5,50
Soft handover MDC gain dB 0,00 1,00
Processing gain dB 17,78 17,78
Interference margin (NR) dB 3,01 8,24
Required Ec/Io [q] dB -15,78 -12,28
Required Signal Power [S] dBm -117,91 -105,18
Cable loss dB 2,00 0,00
Body loss dB 0,00 0,00
Antenna gain RX dBi 18,00 0,00
Soft handover gain dB 2,00 2,00
Power control headroom dB 3,00 0,00
Istropic power dBm -132,91 -107,18
TRANSMITTING END UE Node B
Power per connection dBm 21,00 24,73
Cable loss dB 0,00 2,00
Body loss dB 0,00 0
Antenna gain TX dBi 0,00 18
Peak EIRP dBm 21,00 40,73
Isotropic path loss dB 153,91 147,91
DL peak to average ratio dB 6,00
Isotropic path loss to the cell border 153,91
NRT 64kbit/s, 3km/hNRT 64kbit/s, 3km/hNRT 64kbit/s, 3km/hNRT 64kbit/s, 3km/h
• The calculation is done for
each service (bit rate)
separately
• The link budget must be
balanced

15 2005 Nokia© V1-Filename.ppt / yyyy-mm-dd / Initials
WCDMA Nominal Planning

Create Nominal Plan
• Position a hexagonal grid of
sites over the desired
coverage area.
• The radius of each hexagon
can be determined from the
link budget.
• The capacity of the network
can then be analyzed to
detect:
• Hot spots that require cell
splits.
• Under used cells that could
be removed from the plan.
Example nominal plan for Jersey

Define Search Areas
• The sites in a nominal plan are only imaginary.
• To become a real network, physical sites are required.
• A suitable physical site must be found for each nominal site.
• A suitable physical site must amongst other things:
• Give adequate radio coverage.
• Have connectivity into the transmission network.
• Be aesthetically and politically acceptable to the local community.
• Have power nearby, good access and a co-operative owner.
• A survey of each nominal site is normally carried out to
identify possible site options which meet the above criteria.

Define Search Areas
• Guidelines have to be given to the surveyor so the options
give appropriate radio coverage.
• The guideline is given in the form of a search area. Could be:
• Radius from the nominal site.
• One or more polygons following height contours.
Or

Detailed Site Design
• Prior to commencement of
construction work, a detailed
site design is required.
• Includes
• Antenna and feeder
requirements.
• Antenna azimuths and tilts.
• Equipment capacity
requirements
• Can t be completed in’
isolation. Must take into
account other sites.
60º
60º
180º180º
300º
300º
Ant 1
Ant 2
Ant 5
Ant 4
Ant 6
Ant 3

Setting up NetAct forNominal Planning
Import suitable antenna
patterns
Create UMTS cell layer
Create a UMTS propagation
model
Create UMTS site templates

Create a UMTS Propagation Model
• In a real network rollout
one of the first tasks of
the radio engineers would be
to calibrate a UMTS
propagation model.
• For the purposes of the
following sections we will
assume that this has been
completed.
• Set up a propagation model
with the parameters
described here.
Parameter Setting Clutter Type Offset
Model Type Standard Macrocell Unclassified 0
Frequency 2200 Urban 10
Mobile Rx Height 1.5 Suburban Residential 5
Effective Earth Radius 8491 Village 3
K1 143 Isolated Dwellings 2
K2 42 Open Rural 1
K3 -2.55 Woodland Forest 7
K4 0 Park Recreational 2
K5 -13.82 Industry 5
K6 -6.55 Water 0
K7 0.8 Airport 1
Eff. Ant. Height Relative Open in urban 5
Diffraction Bullington Agricultural land 1
Merge knife edges 0 Pylons 1
Sea 0
Rivers 0

Import Antenna Pattern
• Import the antenna
patterns supplied by the
manufacturers.

Create Coverage Schema & Cell Layer
• The only parameters that are
necessary to set on the cell
layer are the signal thresholds
and the coverage schema.
• These are derived from the
link budgets used in the
network dimensioning.

Create Site Templates
• Create default nominal sites
• either an omni site.
• and/or a sector site.
• 3 sector parameters listed
here.
Level Tab Field Setting
Site General Hex Radius #1
Cell General Model UMTS
Cell Cell Config Antenna 85 XP
Cell Cell Config Downtilt 4
Cell Cell Config Height 20
Cell Cell Config Azimuth #2
UMTS cell layer Antenna/TRX PA output 33
#1 Will depend on area type eg
Urban/Suburban/Rural
#2 Typically either 0º, 120º, 240º
or 60º, 180º, 300º.

Creating a Nominal Plan
• From the link budgets,
identify the cell radius for
each environment to be
planned.
• Create a UMTS site template
• For each environment,
position a hexagonal grid of
sites with the appropriate
cell radii over the target
coverage area.

Locating Urban Nominal Sites
• Define mid hexagon radius as
1100m and select in the site
template.
• Position a grid of
sufficient sites to cover
the urban areas.

Locating Rural Nominal Sites
• Select Hexagon Radius in the
site template to be 4400m.
• Position a grid of sufficient
sites to cover the rural
areas.

Evaluate Nominal NetworkCoverage
• Run a coverage array for
the nominal network.
• Check that the coverage is
in line with your expectations.
• Adjust site locations and add
additional sites if
improvements to coverage is
necessary.
• Check for excessively high
sites.

Evaluate Nominal NetworkCapacity
• Create a traffic raster for
each service.
• Create a terminal type for
each service.
• Spread traffic for each
terminal type to simulate
users.
• Analyze how much traffic
each cell will pick up
(capture).
• Evaluate if each cell has
sufficient capacity.
Create Traffic Raster
Capture Traffic
Evaluate Each Cells
Required Capacity
Re-Engineer Network
(if required)

Create Terminal Types
• Create a circuit switched
terminal type for each
service.
• Allocate traffic to simulate
users.
• Voice = 200 Erlangs
• 384 kb/s = 100 Erlangs
(simulating 100 terminals)
Clutter Type Weight
Urban 500
Open in urban 30
Suburban Residential 20
Industry 10
Village 10
Airport 5
Park Recreational 5
Woodland Forest 2
Agricultural land 1
Isolated Dwellings 1
Open Rural 1
Pylons 1
Rivers 0
Sea 0
Unclassified 0
Water 0

Spread Voice Traffic
• Spread the traffic on the
voice terminal type over the
island.

Create Coverage Array (Voice)
• Set the minimum service
level in the Array Settings
window to match the
minimum threshold for
speech services.
• i.e. -114dBm
• Create coverage array as
usual.

Analyze Voice Traffic
• Use the traffic analysis tool
to estimate the voice
traffic per cell.
Cell: CS Traffic(E)
Site0A: 1.27874
Site0B: 18.989
Site0C: 2.64128
Site1A: 18.1042
Site1B: 0.099755
Site1C: 1.71587
Site2A: 2.13376
Site2B: 1.58312
Site2C: 105.062
Site3A: 11.8475
Site3B: 2.43671
Site3C: 12.1231
Site4A: 2.06883
Site4B: 1.76368
Site4C: 1.87409
Site5A: 1.58884
Site5B: 3.31571
Site5C: 3.13637
Site6A: 1.81907
Site6B: 3.5485

Spread Data Traffic
• Spread the traffic on the
data terminal type over the
island.

Create Coverage Array (Data)
• Set the minimum service
level in the Array Settings
window to match the
minimum threshold for data
services.
• i.e. -96dBm
• Create coverage array as
usual.

How do I asses a site option?
• Each site needs to be assessed on several grounds.
• Radio
• Transmission
• Access
• Power
• Planning
• Ideally every site option reported by the surveyor
would pass in each of the areas listed above.

Bad GSMSites
• In GSM, there were two types of bad sites.
• Donkeys - Low sites which provide very little coverage.
• Donkeys carry so little traffic that they often never pay for
themselves.
• Boomers - High sites which propagate much further than is
needed.
• A boomer will cause localised interference and prevent capacity being
added to some other sites in the area.
Small “Donkey” site Large “Boomer” site

Bad UMTS Sites
• Good radio engineering practice doesn t change much for’
UMTS.
• It just becomes more important.
• In UMTS
• A Donkey will never pay for itself.“ ”
• A Boomer will reduce the range and capacity of surrounding“ ”
sites.
• Two major factors determine whether a site is considered
good, a Donkey or a Boomer , They are:“ ” “ ”
• Site location.
• Antenna height.
• Other parameters can be used in an attempt to control
booming sites but it is far better to avoid building them in
the first place.

Site Selection Guidelines
• The objective is to select a site location which covers the
desired area but keeps emissions to a minimum.
• The site should be located as close to the traffic source as
possible.
• The closer the site is to the traffic, the less output power will
be required by the user equipment and node B. This will minimise
the noise affecting other users on both the serving cell as well
as other nearby cells.
• The antenna height selected will depend largely on the type
of environment in which the site is to be located. Eg Dense
Urban, Urban, Suburban, Rural.
• The key factor to be considered is how well can the
emissions be controlled.

Using Existing CellularSites
• Most UMTS networks will be built around an existing GSM
network.
• Many GSM networks were built around existing analogue
sites.
• In the early days of analogue cellular sites were often
located to give maximum coverage. No thought was given to
capacity issues.
• Despite causing problems in high capacity networks, many of
these high sites are still in operation today.
• Most cellular networks contain these nightmare sites.
• When rolling out UMTS around an existing network it is vital
to avoid these sites.

UMTS Configurations
• Most vendors support the same basic configurations.
• Omni
• 3 sector
• 6 sector
• Each vendor supports their own variations on these
configurations.
• Some solutions eliminate the need for RF plumbing.
• Some require similar amounts of equipment to a GSM BTS.
• Some increase the number of antennas on a site.
• The configuration can be affected by the wide variety of
UMTS antennas.

Co-locating a Node Bat a GSMsite
• Isolation requirements between UMTS and GSM systems can
be derived from UMTS and GSM specifications.
• In many cases equipment performance will exceed the
requirements in the specifications.
• Each vendor should be able to provide information which can be
used to improve the isolation requirements.
• The isolation requirements will affect
• Choice of antenna configuration
• Filtering at both the GSM and UMTS sites.
• Isolation is the attenuation from the output port of a
transmitter to the input port of the receiver.

Interference Issues
• Wideband Noise - unwanted emissions from modulation
process and non-linearity of transmitter
• Spurious Emissions - Harmonic, Parasitic, Inter-
modulation products
• Blocking - Transmitter carriers from another system
• Inter-modulation Products - Spurious emission,
specifications consider this in particular
• Active: non-linearities of active components - can be filtered
out by BTS
• Passive: non-linearities of passive components - cannot be
filtered out by BTS
• Other EMC problems - feeders, antennas,
transceivers and receivers

Isolation Requirements
GSM 900 GSM 1800 UMTS
Receiving band
(UL)
890 – 915 MHz 1710 – 1785 MHz 1920 – 1980 MHz
Transmitting band
(DL)
935 – 960 MHz 1805 – 1880 MHz 2110 – 2170 MHz
GSM 1800 TxGSM 1800 Tx
1805 MHz1805 MHz 1880 MHz1880 MHz
UMTS RxUMTS Rx
1920 MHz1920 MHz 1980 MHz1980 MHz
GSM 1800 RxGSM 1800 Rx
1710 MHz1710 MHz 1785 MHz1785 MHz
UMTS RxUMTS Rx
2110 MHz2110 MHz 2170 MHz2170 MHz
For example - To prevent UMTS BTS blocking: with transmit power = 43 dBmFor example - To prevent UMTS BTS blocking: with transmit power = 43 dBm
Max level of interfering signal for blocking = -15 dBm in UMTSMax level of interfering signal for blocking = -15 dBm in UMTS
Isolation required = 58 dBmIsolation required = 58 dBm

Achieving Isolation Requirements
• Isolation can be provided in a
variety of different ways.
• By antenna selection and positioning.
• By filtering out the interfering
signal.
• By using diplexers and triplexers
with shared feeder and multiband
antennas.
UMTSUMTS
GSMGSM
FilterFilter
UMTSUMTS
GSMGSM
DiplexerDiplexer
UMTSUMTS
GSMGSM

Co-siting - Antenna Installations
• Difficult to calculate isolation between two antennas
and measurements are required.
• Best configurations - antennas pointing in different
directions or where there is vertical separation
between antennas
• The following configurations will should all give 30dB
isolation.
dd
dd
dd
90º90º 120º120º
dd
dd
180º180º
dd
d = 0.3 - 0.5 md = 0.3 - 0.5 m d = 1 - 3 md = 1 - 3 m d = 0.5 - 2 md = 0.5 - 2 m

Site sharing with third party systems
• Some UMTS sites might be
co-located with other non
GSM operators.
• PMR
• Broadcast
• Navigation
• Some of these systems
use older equipment which
might be more vulnerable to
EMC issues.
• Need to define minimum
antenna separations
between systems
• Better to avoid sites used
for safety critical
applications.
UMTS antennas
Other systems
Minimum separation

Antenna installation issues: Clearance angle
h (meters)
d (meters)
Clearance angle
• Rules of thumb:
• h ≥ d/2, d < 10 m
• h ≥ d/3, 10 < d < 20 m
• h ≥ d/4, d > 30 m
Antenna
d (meters)
Top view
Side view

Antenna installation
d has to be >
3.2 m
• Safety margin of 15° between the reflecting surface and the 3 dB lobe

Antenna installation: OtherRF-systems
Not Acceptable
DOCUMENTTYPE 1 (1)
TypeUnitOrDepartmentHere
TypeYourNameHere TypeDateHere
Acceptable
Be careful with
back-lobe!

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