Optimización de red_de_acceso-final

Optimización de Redes Celulares
Problemas comunes en RAN que pocos verifican, ¿Los
conoce? Caso de Estudio
Italo Tertuliano
Organización de Especialistas en Soluciones Inalámbricas – Latinoamérica.

© 2013 JDS Uniphase Corporation | JDSU CONFIDENTIAL AND PROPRIETARY INFORMATION 2
Enterprise &
Customer Network
Core IP Network
or MSC
Backhaul Network Radio Access Network
QT-600
Ethernet
Probe
T-BERD/
MTS-6000a
Assurance
Drive TestSignaling
Analyzer
Active Test
HST-3000HP3-60
Internet
SAN
Video
Server
Content
Server
SONET/SDH
ATM
Ethernet
PSTN
40 G
100 G Backhaul
SONET/SDH
Ethernet
SAN
1G
40 G
10 G
10 G
1 G
Mobile
Device
Mobile
Device
Data
Center
Home
Remote
Office
SANEnterprise
Femto
Cell
Cell
Site
Cell
Site
4 G / LTE
2 G
3 G
4 G/LTE
2 G
3 G
Cell
Site
4 G/LTE
2 G
3 G
Functional &
Capacity Test
Packet Capture
HP2-60
Scope
FFL-050
Pocket VFL
OTU-8000
Backhaul
monitoring
BTS & Cable
Analyzers
PacketPortal
Arieso Customer
Experience
Management
Making it Work – Comprehensive JDSU Portfolio
1. Backhaul
Certification
2. RBS
Certification
3. Service
Certification

El elemento mas importante de la RAN.
BACKHAUL
Prueba
Ethernet/E1
Línea de Transmisión
Análisis de Cable y
Antena
Interfaz Aérea (OTA)
Análisis de
Señal.
Espectro
Análisis de
Interferencia.
Análisis
Multitrayectoria
Evaluación RBS
Medición de Potencia
óptica o RF
Análisis de señal
Análisis de Espectro
JD745A

Tipos de RadioBases
COPPER
FRONTHAUL
Conventional
Cell-sites
FIBER & COPPER
FRONTHAUL
Distributed
Cell-sites
RRH or RRU Copper
Fiber
FIBER
FRONTHAUL
Active Antenna
Small Cell-sites
Distributed
Antenna Systems
FIBER
FRONTHAUL
Installs Conventional Distributed DAS Small-cells
Deployed +++ ++ ++ +
Trend + ++ ++ +++

Ejemplos RBS.

Ejemplos RBS

Ejemplos de RBS.

Ejemplo DAS.

 Una gran cantidad de problemas en las radio bases se debe a la reflexión en el
cable.
 Por corrosión, oxidación y residuos de agua en la línea de transmisión.
Cable & Antenna Analyzer
La prueba más comun en una RBS.
Reflection: 0%
VSWR: 1
Reflection: 67%
VSWR: 5
Reflection: 97%
VSWR: 65
IDENTIFY LOCATE VERIFY
VSWR

DTF and Cable Loss
Distance to Fault (DTF) Cable Loss
DTF es un reflectómetro que identifica la
distancia a las reflexiones de la señal.
Cable loss: verifica las características del
cable midiendo la atenuación en una
frecuencia conocida.

Power Meter and Gain Meter.
Power Meter
Power Meter: controla un medidor de
potencia de RF. (interno o externo)
TMA
BTSANTENNA
LNA
BIAS
TEE
TMA
BTSANTENNA
LNA
Gain Meter: Pruebas de ganancia para
Tower Mounted Amplifiers (TMA).
Gain Meter
EXTERNAL
INTERNAL

Los 3 pasos para CALIDAD en la red.BackhaulCert
Fiber Cleaning
Backhaul
characterization
RFC 2544,
Y.1564, and True
Speed
One button pass
fail test
One page report
RBSCert
Radio
performance
direct connect
Air interface tests
Signal analysis
Transmission
tests
One button
pass/fail test
One page report
ServiceCert
Site
commissioning
tests
Handover tests
Service
sequences
Voice Quality
Go-no-Go
One page report
JDSU Classic CellAdvisors RANAdvisors

1
2
4
3
POWER
FREQUENCY
Signal Analysis
WCDMA Measurements
5
6
Signal Analysis
WCDMA Measurements
RF Analysis
Modulation
Analysis
Channel
Power
Occupied
Bandwidth
ACPR
SEM
Spurious
Emissions
Constellation
Code Domain
Power
RCSI
Codogram
CCDF
1
2
4
2
3
3
4
4
4
1
3
CDP Table
4
Over The Air
Analysis
Channel
Scanner
PN Scanner
CDP
Multipath
5
6
5
5

Signal Analyzer
Spectrum Analysis
 Conformance Testing:
• Channel Power
• Occupied Bandwidth
• Adjacent Channel Power
• Spectrum Emission Mask
OCCUPIED BANDWIDTH
CHANNEL POWERADJACENT CHANNEL POWER
SPECTRUM EMISSION MASK
Configurable limits
for automated PASS
/ FAIL indication

Base Station Analyzer
CDMA & WCDMA - Modulation Analysis
CODE DOMAIN POWER
CODOGRAM
RECEIVED CODE STRENGTH INDICATOR
ADJACENT CHANNEL LEAKAGE RATIO
SIGNAL FORMAT
WCDMA
F
P
CONFORMANCE TESTING
CONSTELLATION

Resultados de pruebas automatizadas.

Análisis de Señal.
Mediciones LTE.
Signal Analysis
LTE Measurements
RF Analysis
Modulation
Analysis
Channel
Power
Occupied
Bandwidth
ACLR
SEM
Spurious
Emissions
Data
Channel
Control
Channel
Frame
Subframe
Power vs.
Time
1
2
3
4
5
6
POWER
FREQUENCY
TIME1
2
3
4
5
5
7
64
6
3 6
3 6
2
7
9
8
Over The Air
Analysis
ID Scanner
MIMO
Control
Channel
8
9
9

LTE - RF Analysis
CHANNEL POWER
SPECTRUM EMISSION MASKOCCUPIED BANDWIDTH
ADJACENT CHANNEL LEAKAGE RATIO
SIGNAL FORMAT
OFDMA
F
P
T
CONFORMANCE TESTING

LTE Overview
Channel
Bandwidth:
10 MHz
Transmission
Bandwidth:
9 MHz
POWER
FREQUENCY 15 kHz
Subcarriers (Sc)
POWER
TIME
Symbols (Sy)
1 2 3 4 5 6 7
Slot
LTE 10 MHz : 9 MHz / 15 kHz = 600 Sc
1 Frame (10 ms) = 10 sub-frames (1 ms) = 20 slots (0.5ms)
FREQUENCY
POWERPOWER
Resource Block (RB) = 12 Sc x 7 Sy = 84 Resource Elements
POWER
FREQUENCY
TIME
Symbol (Sy)
Subcarrier (Sc)
Resource
Block
TIME
FREQUENCY
7 Symbol (Sy)
12 Subcarrier (Sc)
Resource
Element
0 1 2 3 18 19
Slot
Subframe
Frame
0 1 2 3

Reference Signal PBCHPDCCH PDSCH P-SCH S-SCH
FREQUENCY
TIME Resource Block
Slot
Sub-frame
Frame
15 kHz
Signal Analysis
LTE Downlink Signal Map
Resource Element

Signal Analysis
LTE Downlink Channels
DL
Channels
Description
Modulation
Format
Purpose
PBCH Physical Broadcast channel QPSK Carrier Cell specific information.
PDCCH
Physical Downlink Control
Channel
QPSK
Transports format, resource and hybrid-ARQ information
related to DL-SCH, UL-SCH and PCH.
PDSCH
Physical Downlink Shared
Channel
QPSK, 16QAM,
64QAM
User data payload.
PMCH Physical Multicast Channel
QPSK, 16QAM,
64QAM
Payload for multiple users, Multimedia Broadcast Multicast
service (MBMS)
PCFICH
Physical Control Format
Indicator Channel
QPSK
Carries the number of symbols (1,2 or 3) used for control
channels (PDCCH) in a subframe.
PHICH
Physical Hybrid ARQ
Indicator Channel
BPSK
Carries the error detection (hybrid ARQ ACK/NAK) feedback to
the UE for the UL blocks received by the eNB.
P-SCH
Primary Synchronization
Channel
Zadoff – Chu
Used for cell search and cell identification. Carries part of the
cell ID
S-SCH
Secondary Synchronization
Channel
BPSK
Used for cell search and cell identification. Carries the
remainder of the Cell ID
RS Reference Signal (Pilot)
Complex I+Q pseudo
random sequence
Used for DL channel estimation. Exact sequence derived form
Cell ID. Enable UE to calculate transmission corrections.
Page 23
MODULATION SCHEMES

LTE - Modulation Analysis
DATA CHANNELS
CONTROL CHANNELS
SIGNAL FORMAT
OFDMA
F
P
T
CONFORMANCE TESTING SUBFRAME SUMMARY
FRAME SUMMARY

Principales canales de control LTE.
PDCCH
P-SCH, S-SCH
PBCH
RB
A
B
C
D
DA
C
B
La potencia es analizada en símbolos
y tramas para diferenciar canales de
datos y canales de control.
Potencia contra Tiempo

Quality of Experience
User Throughput – Modulation
CQI
PDSCH
MODULATION
0 Out of range
1 to 6 QPSK
7 to 9 16QAM
10 to 15 64QAM
Channel State Information
Channel Quality Indicator
Channel Quality
Indicator
Reference Signal
QPSK
00 01
10 11
16QAM
0000
1111
64QAM
000000
111111
Modulation Schemes PDSCH, PMCH
Modulation Schemes RS
QPSK
00 01
10 11

Signal Analysis
Modulation
 Digital bits are transferred onto an RF carrier through modulation. Modulation
can be based on three components: amplitude, phase, or frequency.
 Modulated signals can be analyzed by polar diagrams (magnitude and phase)
represented by its rectangular components: I (In-phase) and Q (Quadrature).
AMPLITUDE FREQUENCY PHASE AMPLITUDE AND PHASE
AMPLITUDE FREQUENCY PHASE AMPLITUDE AND PHASE
Q
I
Q
I
Q
I
Q
I

Signal Analysis
Modulation
 Modulation formats
 Modulation quality metric (EVM)
• The Error Vector Magnitude is a measure of the difference between
the ideal symbols and the measured symbols. It is defined as the
square root of the ratio of the mean error vector power to the mean
reference power expressed in percent.
• I/Q Errors:
BPSK Zadoff-ChuQPSK 16QAM 64QAM
0 1
00 000
000001
10 11
000000
32QAM
00000
Error Vector
Magnitude
Origin Offset Gain Imbalance Quadrature Error

 Modulation quality will indicate the modulation scheme (data
throughput) assigned to each user.
Transmission Analysis
Throughput Case – Channel Quality Indicator
MODULATION
QUALITY
LOW MODULATION
QUALITY
LOW DATA
THROUGHPUT
HIGH MODULATION
QUALITY
HIGH DATA
THROUGHPUT
DATA
THROUGHPUT
USER
EXPERIENCE
Spectrum Analysis

LTE Quality of Experience
User Throughput – Modulation
CQI
PDSCH
MODULATION
0 Out of range
1 to 6 QPSK
7 to 9 16QAM
10 to 15 64QAM
REFERENCE SIGNAL USER DATA (PDSCH)
CQI
PDSCH
MODULATION
0 Out of range
1 to 6 QPSK
7 to 9 16QAM
10 to 15 64QAM
CQI
PDSCH
MODULATION
0 Out of range
1 to 6 QPSK
7 to 9 16QAM
10 to 15 64QAM
LTE Bandwidth
Channel bandwidth (MHz) 10.0
TX bandwidth (MHz) 9.0
RB per timeslot (0.5 ms) 50
64QAM MIMO 2x (Mbps) 100.8
LTE Bandwidth
QPSK MIMO 2x (Mbps) 33.6
Bandwidth reduction -66.7%
LTE Bandwidth
LTE Bandwidth
Bandwidth reduction -33.3%
LTE Bandwidth

 Test conditions for LTE over-the-air analysis:
‒ Modulation Quality
‒ MIMO Performance
LTE – Over The Air Analysis
Measurement Setup
CELLADVISOR JD745A
300 FT
ANTENNA
TILT AND
MIMO
DIRECTIVITY
Measurement Conditions:
Channel Power > -50 dBm
Modulation Quality
Antenna 1 (RS0) EVM < 10%
MIMO performance:
RS0 and RS1 power
difference < 10dB
RS0 and RS1 time alignment
error < 65ns

Sector Alpha
CHANNEL POWER > -50dBm RS0 – RS1 < 10dB & < 65ns
RS0 EVM < 10% RS1 EVM < 10%
PCI: 341, 113, 2
Modulation Quality
MIMO performance:
RS0 and RS1 power
difference < 10dB
error < 65ns

Sector Beta
RS0 EVM < 10% RS1 EVM < 10%
PCI: 340, 113, 1
Modulation Quality
MIMO performance:
RS0 and RS1 power
difference < 10dB
error < 65ns

Sector Gamma
RS0 EVM < 10% RS1 EVM < 10%
PCI: 339, 113, 0
Modulation Quality
MIMO performance:
RS0 and RS1 power
difference < 10dB
error < 65ns

Quality of Experience
Synchronization
CELL-SITE TIMING MODULE SIGNAL MODULATION
CELL-SITE TIMING MODULE SIGNAL MODULATION
eNodeB Synchronized
eNodeB Free-run

MIMO Performance
Resource Block
Time(Symbols)
R0 R0
R0 R0
Frequency (Subcarriers)
R0: RS Antenna 0
Resource Block
Time(Symbols)
Frequency (Subcarriers)
R1: RS Antenna 1
R1 R1
R1 R1
ANT-0 FRAME
ANT-1 FRAME
Power
Frequency
RS(0)
Frequency
RS(1)
PWR [RS(0)] PWR [RS(1)]
PWR [RS(0) – RS(1)]
Power
T0 T1
TAE: [T1 – T0]
LTE OTA CONTROL

Diversity - Coverage
 Same user data is transmitted from multiple
antennas.
 Provides better reception in Improves environments
with high multipath and fading.
MIMO Performance
Spatial Multiplexing - Capacity
 Different user data is transmitted from multiple
antennas.
 This creation of parallel communication channels or
layers improves bandwidth utilization.
REFERENCE SIGNAL - 1
LTE Reference Signals (RS) and User Experience
 MIMO creates multiple communication layers, increasing capacity. The mobile can decode
those layers based on the signal quality from each antenna (RS0 and RS1).
REFERENCE SIGNAL - 2
+ High Modulation Quality (RS0 & RS1) =
Double Capacity

LTE OTA - MIMO
Control Channel and Multipath
LTE MIMO Multipath
LTE MIMO Power and Time
UNIQUE TO JDSU
 Desempeño MIMO, probar potencia,
reflexión y modulación de cada antena
(RS0 and RS1).

 In spatial multiplexing throughput cuts by half with antenna failures
MIMO Performance
Over the Air Analysis
ANTENNA 0
ANTENNA 1
Radio Connection
ANTENNA 0
ANTENNA 1
FAULTY ANTENNA

 Crossed cables to the antennas can create a series of service outage
and high maintenance cost due to multiple antenna replacements.
MIMO Performance
Over the Air Analysis
ANTENNA 0
ANTENNA 1
Radio Connection
ANTENNA 0
ANTENNA 1
CROSSED CABLES
AT RRU
TX1 – TX2
TX2 – TX1
TX2
TX1
TX1
TX2

Interference
Resource
Block
Power
FrequencyDistorted
Resource
Blocks
Non-linear
amplification or
filtering
Resource
Block
Power
FrequencyDistorted
Resource
Block
Interference
LTE Bandwidth
Channel bandwidth (MHz) 1.4 3.0 5.0 10.0 15.0 20.0
TX bandwidth (MHz) 1.1 2.7 4.5 9.0 13.5 18.0
RB per timeslot (0.5ms) 6 15 25 50 75 100
64QAM MIMO 2x (Mbps) 12.1 30.2 50.4 100.8 151.2 201.6
LTE Bandwidth (1 distorted RB)
RB per timeslot (0.5 ms) 5 14 24 49 74 99
64QAM MIMO 2x (Mbps) 10.1 28.2 48.4 98.8 149.2 199.6
Bandwidth reduction -16.7% -6.7% -4.0% -2.0% -1.3% -1.0%
LTE Bandwidth
Channel bandwidth (MHz) 1.4 3.0 5.0 10.0 15.0 20.0
TX bandwidth (MHz) 1.1 2.7 4.5 9.0 13.5 18.0
64QAM MIMO 2x (Mbps) 12.1 30.2 50.4 100.8 151.2 201.6
LTE Bandwidth (7 distorted RBs)
64QAM MIMO 2x (Mbps) --- 15.8 35.4 84.7 133.9 187.5
Bandwidth reduction -100% -46.7% -28.0% -14.0% -9.3% -7.0%

Signal Analysis – Scheduling of Resource Blocks
Data channel measurement provides a resource block granularity in one
subfarme.
Applicable for test models described on TS 36.141: 6.1.1
Data channel measurements verifies proper scheduling of resources
(resource blocks) as well as the complete modulation assessment of data
channels (traffic) such as power, EVM, and constellation.
Data Channels
Spectrum Analysis

Signal Strength – Built-in Mapping
GPS-based and Position-based Tracking
GPS Based Tracking
Position Based Tracking
 Indicates the signal strength in the area covered by a cell-site.
 Indicates the signal strength and cell-IDs in distributed antenna systems
(DAS) environments.

RF CONFORMANCE MODULATION QUALITY CELL-SITE COVERAGE
RF Conformance Modulation Quality
Channel Power
Occupied Bandwidth
ACLR
SEM
Spurious Emissions
Data Channel
Control Channel
Frame
Subframe
Power vs. Time
CCDF
1
2
3
4
5
5
7
64
6
3 6
3 6
1
2
Cell-site Coverage
ID Scanner
Multipath
Control Channel
8
9
9 1
2
3
4
5
6
POWER
FREQUENCY
TIME
7
Making it Work – RBS Certification

CellAdvisor – JD745A
Listos para el futuro.
LTE Control PIM Detection
LTE MBMS Remote Control Bluetooth
LTE MIMO
LTE Advanced

Enterprise &
Customer Network
Core IP Network
or MSC
Backhaul Network Radio Access Network
QT-600
Ethernet
Probe
T-BERD/
MTS-6000a
Assurance
Drive TestSignaling
Analyzer
Active Test
HST-3000HP3-60
Internet
SAN
Video
Server
Content
Server
SONET/SDH
ATM
Ethernet
PSTN
40 G
100 G Backhaul
SONET/SDH
Ethernet
SAN
1G
40 G
10 G
10 G
1 G
Mobile
Device
Mobile
Device
Data
Center
Home
Remote
Office
SANEnterprise
Femto
Cell
Cell
Site
Cell
Site
4 G / LTE
2 G
3 G
4 G/LTE
2 G
3 G
Cell
Site
4 G/LTE
2 G
3 G
Functional &
Capacity Test
Packet Capture
HP2-60
Scope
FFL-050
Pocket VFL
OTU-8000
Backhaul
monitoring
BTS & Cable
Analyzers
PacketPortal
Arieso Customer
Experience
Management
Making it Work – Comprehensive JDSU Portfolio
1. Backhaul
Certification
2. RBS
Certification
3. Service
Certification

RANAdvisor Handheld.
• Prueba redes en Indoor y Outdoor.
• Fácil de utilizar.
• Primero en el mercado.
• Reconocimiento como solución LTE
• Modelos Symbian y Android.

 Modo Indoor y Outdoor.
 Pruebas de datos
• FTP (UL/DL)
 Pruebas de Voz
 Pruebas HTTP
 Pruebas Ping
 Pruebas CSFB
• Circuit Switch Fall Back
• Datos LTE, Voz 3G.
Pruebas clave FTA.

 iPERF
• TCP y UDP
 MMS
 E-mail
 SMS
 Layer 3 on screen
 MOS (POLQA)
Pruebas nuevas FTA.

Casos de uso FTA.
Pruebas automatizadas con
múltiples FTA en un mismo
individuo.
Utilizado para recorridos en
lugares cerrados, en dónde
se especifica la ruta a seguir.
RF MULTIMETER INDOOR
Con el GPS interno, geo-
localiza la medición al
conducir. No hay necesidad
de PC.
MOBILE
Calidad en tiempo real en
los eventos, realizando el
desempeño de llamadas,
datos, etc.
Eventos
Conocer a detalle la
cobertura de un área
específica.
Area de Despliegue
Evaluar en campo un
cambio de configuración a la
RBS o apoyo en Interference
Hunting.
Modificaciones de eNodeB

1) Drive Test Proactivo.
Garantizar radio y aplicación:
 Cobertura RF
 Limpieza del espectro UL/DL
 Planificación de la capacidad
 RF QoS
2) Drive Testing Reactivo
Solución de problemas basado en quejas:
 Llamadas fallidas.
 No hay señal de cobertura.
 Problemas en Handover o Handoff entre tecnologías.
 Problemas de conexión a Internet.
 Problemas en el Throughput de la red de datos.
Tipo de soluciones JDSU para outdoor:
 Combo: Optimización/ troubleshooting/ benchmarking
 Solo Teléfono: Mirando el QoS desde el punto de vista del abonado
 Solo Receiver: Mirando la RF, interferencia, o propagación de señal
Uso típico de Drive Test outdoor

 Del (UE)
 Physical Cell Information
 Cell Signal Quality Info
 RLC Throughput
 PDSCH PHY Throughput
 Scheduling Status
 LTE Antenna Correlation
 Protocolos en capa 3
Principales indicadores de rendimiento en la interfaz
de aire
 Del Receiver/Scanner
 P-SS RSSI
 S-SS RSSI
 Cell-ID
 RS- RSRP
 RS - RSRQ
 RS – CINR (JDSU)
Teléfono proporciona ‘Cual’ y el Receiver proporciona el ‘Por qué’

En continuo desarollo.
New: WiFi
Terminales soportadas.
LTE
• Samsung
• LG
• Qualcomm
• Sequans
• Altair
GSM / UMTS / HSPA/HSPA+ Dual Carrier
• Nokia, Qualcomm, Motorola
• Samsung, LG, Novatel, Sagem, Sierra Wireless,
Option, Huawei, etc.
IS95 / cdma2000 / 1xEV DO
• Qualcomm
• Sierra Wireless, Kyocera, LG, Novatel
TD-SCDMA
• Datang
iDEN
• Motorola
JDSU Test UE/Chipset Support List

 Se detecta la zona de bajo desempeño.
Optimización - Ejemplo

Detalle Ruta.

Pilot Pollution - Exceso de canales pilotos.

Pilot Pollution

Análisis Cross Feeders

RSRP Google Earth.

Serving Network
PS Core (Data)
Interfaces 3GPP Soportadas en SART.
Core & Services Network
CS Core (Voice)
SGSN
MSC/VLR
GSM-A
GPRS-Gb
Iu-CS
Iu-PS
S4S3 Gx
SGi
S1-C
S12
Gn
GGSN
GSM/GPRS/EDGE Radio Access Network (GERAN)
Base Station Subsystem (BSS)
BTS
MS
Abis
GSM
EDGE
Evolved EDGE
BSC
Um
Evolved UTRAN (E-UTRAN)
Uu
Evolved Node B
X2UE
LTE
LTE Advanced
UMTS Terrestrial Radio Access Network (UTRAN)
Radio Network Subsystem
NodeB
RNC
UE
Iub
RNC
Iur
W-CDMA
HSPA/HSPA+
Iub
Uu
HSS
CSCF
MRF
Evolved Packet Core (EPC)
S-GW
MME
P-GW
S11
S5
S10
S6a
Public
Data
Network
Gi
PCRF
WSP Services
(IMS, VCC, …)
SS7/SIGTRAN
SGW
SMS
HLR/HSS
MGW
Mc
Nb
D/Gr
MGW
Nc
Rx
S1-U
Supported Interfaces

Call trace con SART

NEM
Portafolio JDSU
Operadores de Red
Diseño y
Producción
Pruebas de
carga y
configuración
Planeación y
Diseño.
Instalación
Optimización y
Mantenimiento
Monitoreo
QoS y
facturación
Analizadores de Protocolos - SART
Analizadores Ethernet y Fibra óptica
Analizadores de Radio Bases.
Drive Test
RCATS - Assurance
Pruebas de
capacidad.
Terceros:
• Instalación de RBS.
• Servicios Drive Test.

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