LTE Planning

2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 R99 R4 R5 R6 R7 R8 R9 R10 UM TS HSP A DL HSP A UL LTE LTE Ad v HSP A + EPC Common IMS IMS M M Tel

LTE Requirement (3GPP TR 25.913)

• Peak data rate 100 Mbps (DL) and 50 Mbps (UL) to 20 MHz

• Throughput increased by 3-4 times and 2-3 times for the downlink to uplink from HSDPA Rel 6 ( DL = 14.4 Mbps , to use transmitter sites that have been used in UTRA / GERAN

• Throughput increased by 3-4 times and 2-3 time UL = 5.7 Mbps )

• Spectrum efficiency by continuing as for the downlink to uplink from HSDPA Rel-6 (DL = 14.4 Mbps, UL = 5.7 Mbps)

• Flexible use of spectrum (1.4, 3, 5, 10, 15, 20 MHz) • Lower latency :

– Radio access network latency ( user plane UE – RNC- UE ) below 10 ms • The ability of the use mobility up to 350 km / hour

• Coverage up to a radius of approximately 5 km

• Enhance MBMS ( Multimedia Broadcast / Multicast Service ) efficiency ( 1 bit/s/Hz)

• Retaining 3GPP RAT ( Radio Access Technology ) which already exist and support internetworking with him.

LTE Architecture

In the LTE network is divided into 2 basic network, namely:

1. E UTRAN (Evolved Universal Terrestrial Radio Access Network) 2. EPC (Evolved Packet Core)

SERVICE

 The IP Multimedia Sub-System (IMS) is a good example of service machinery that can be used in the Services Connectivity Layer to provide services on top of the IP connectivity provided by the lower layers.

 For example, to support the voice service, IMS can provide Voice over IP (VoIP) and interconnectivity to legacy circuit switched networks PSTN and ISDN through Media Gateways it controls.

EPC

• Functionally the EPC is equivalent to the packet switched domain of the existing 3GPP networks.

• EPC consist of :

– MME ( Mobility Management Entity )

– SAE GW represents the combination of the two gateways, Serving Gateway (S-GW) and Packet Data Network Gateway (P-GW)

– Home Subscriber Server (HSS)

– Policy and Charging Rules Function (PCRF)

 Mobility Management Entity (MME)

– MME is a controller at each node on the LTE access network. At UE in idle state (idle mode), MME is responsible for tracking and paging procedure which includes retransmission therein.

– MME is responsible for selecting SGW (Serving SAE Gateway) which will be used during initial attach EU and the EU time to do intra - LTE handover.

– Used for bearer control, a different view R99 / 4 which is still controlled by the gateway

 Policy and Charging Rules Function (PCRF)

In order to handle QoS as well as control rating and charging, and billing

 Home Subscriber Server (HSS)

For management and security subscriber, combination AUC and HLR  Serving SAE Gateway (SGW)

- Set the path and forwards the data in the form of packets of each user - As an anchor / liaison between the UE and the eNB at the time of the

inter handover

- As a liaison link between the 3GPP LTE technology with the technology (in this case the 2G and 3G)

 Gateway Packet Data Network (PDN GW)

- Provides for the UE 's relationship to the network packet

- Provide a link relationship between LTE technology with technology non 3GPP (WiMAX) and 3GPP2 (CDMA 20001X and EVDO)

E-UTRAN

 Role of Radio Access Network (RAN), namely Node B and RNC is replaced with ENB, so as to reduce operational and maintenance cost of the device other than the simpler network architecture

 E-nodeB functions : all radio protocols, mobility management, header compression and all packet retransmissions

 As a network, E-UTRAN is simply a mesh of eNodeBs connected to neighboring eNodeBs with the X2 interface.

User Equipment

 Functionally the UE is a platform for communication

applications, which signal with the network for setting

up, maintaining and removing the communication links

the end user needs.

 This includes mobility management functions such as

handovers and reporting the terminals location, and in

these the UE performs as instructed by the network

Key Consideration to Spectrum Selection

Channel Bandwidth Flexibility

 LTE provides channel bandwidth flexibility for operation in

differently-sized

 LTE supports paired and unpaired spectrum on the same

hardware spectrum

OFDM vs Single Carrier

Spectral efficiency of OFDM compared to classical

multicarrier modulation: (a) classical multicarrier

system spectrum; (b) OFDM system spectrum.

Motivation for OFDM Approaches

• Advantages

– Efficient in the use of frequencies – Highly scalable

– Overcome delay spread, multipath & frequency selective fading, and ISI

• Weaknesses

– Frequency Offset

– Nonlinear Distortion (PAPR)

OFDM Concept

• Multicarrier modulation/multiplexing technique

• Available bandwidth is divided into several sub-channels

• Data is serial-to-parallel converted

OFDM Block Diagram (Tx)

Diagram Block Contents:

• S/P  Serial to Parallel Converter • Sub-Carrier Modulator

• IFFT  Inverse Fast Fourier Transform • P/S  Parallel to Serial Converter

OFDM Block Diagram (Rx)

Diagram Block Contents:

• S/P  Serial to Parallel Converter • Sub-Carrier Modulator

• IFFT  Inverse Fast Fourier Transform • P/S  Parallel to Serial Converter

Cyclic Prefix

• Useful for multipath delay spread

OFDMA vs. SCFDMA

 Definition

 OFDMA is a multiple access technique based on OFDM as the modulation technique. It is used for DL transmission in LTE

 SC-FDMA is a hybrid UL transmission scheme in LTE which has single-carrier transmission systems with the long symbol time and flexible frequency allocation of OFDM.

SC-FDMA Diagram Block

SC-FDMA frequency-domain transmit processing (DFT-S-OFDM) showing localized and distributed subcarrier mappings.

Type of OFDMA Sub-Carrier

 Data sub-carrier

– Carry QPSK, 16 QAM, 64 QAM symbol

 Pilot sub-carrier

– It is used to facilitate channel estimation and coherent

demodulation at the receiver

 Null sub-carrier

– Guard sub-carrier

– DC sub-carrier

Subcarrier Mapping

(N_pilot-2)/2 N_{subcarrier data} / 2

PI

LO

T

N_{subcarrier data} / 2 N_pilot/2

BW

N_{subcarrier data}  See slide #19 or 3GPP TS 36.104 N_pilot  N_FFT-Point - N_{subcarrier data}

Multiple Antenna Technique

Multiple Antenna Technique

 Two popular techniques in MIMO wireless systems:

Spatial Diversity: Increased SNR

• Receive and transmit diversity

mitigates fading and improves link quality

Spatial Multiplexing: Increased rate

• Spatial multiplexing yields

substantial increase spectral efficiency

Spatial Diversity

Transmit Diversity

• Space-time Code (STC): Redundant data sent over time and space

domains (antennas).

• Receive SNR increase about linearity with diversity order N

_r

N

_t

• Provide diversity gain to combat fading

Spatial Multiplexing

MIMO Multiplexing

• Data is not redundant – less diversity but less repetition

• Provides multiplexing gain to increase data-rate

LTE SUPPORTING TECHNOLOGIES

 HARQ  AMC

HARQ

HARQ or retransmission

scheme in LTE use

stop-and-wait retransmission system.

Adaptive Modulation

SNR-CQI Mapping for BLER 10%

Constellation Diagram

QPSK

16 QAM

Adaptive Modulation and Coding

Standard for CQI mapping

Control Plane

Control Plane (C-Plane) is use to describe

the protocols that convey information from the DTE to the end user (the control) of a node, or between nodes in the network to conveying required information to set,

control and clearing the connection protocol.

User plane (U-plane) is a protocol used directly in the transfer of user data from the DTE (Data Terminal Equipment) to the other end-users. U-plane provides the function of delivery or transfer user

information, and include all relevant mechanisms of information

transfer such as flow control and error recovery. In the user plane used approach layer .

Layer Function

• Radio Link Control Layer (RLC)

> Retransmission

> Segmentation

• Medium Access Control Layer (MAC)

> Uplink and downlink scheduling at the eNodeB

> HARQ

• Physical Layer (PHY)

> Modulation/demodulation

> Coding/decoding

LTE Downlink Logical Channels

• Paging Control Channel ( PCCH)

> A downlink channel that transfers paging information and system

information change notifications.

> This channel is used for paging when the network does not know the location cell of the UE

• Broadcast Control Channel (BCCH)

> Provides system information to all mobile terminals connected to

the eNodeB.

> A downlink channel for broadcasting system control information

• Common Control Channel (CCCH)

> Channel for transmitting control information between UEs and

network.

> This channel is used for UEs having no RRC connection with the network.

• Multicast Control Channel (MCCH)

> A point-to-multipoint downlink channel used for transmitting MBMS > Control information from the network to the UE, for one or several

MTCHs.

> This channel is only used by UEs that receive MBMS

• Dedicated Control Channel (DCCH)

> A point-to-point bi-directional channel that transmits dedicated control information between a UE and the network.

> Used by UEs having an RRC connection

> This control channel is used for carrying user-specific control information, e.g. for controlling actions including power control, handover, etc..

LTE Downlink Logical Channel Con’t

• Multicast Traffic Channel (MTCH)

>

A point-to-multipoint downlink channel for transmitting traffic data from the network to the UE.

> This channel is only used by UEs that receive MBMS

• Dedicated Traffic Channel (DTCH )

>

A point-to-point channel, dedicated to one UE, for the transfer of user information.

LTE Downlink Transport Channel

• Paging Channel ( PCH)

> Supports UE discontinuous reception (DRX) to enable UE power saving

> Broadcasts in the entire coverage area of the cell;

> Mapped to physical resources which can be used dynamically also for traffic/other control channels.

• Broadcast Channel ( BCH )

>

The LTE transport channel maps to Broadcast Control Channel (BCCH)

>

Fixed, pre-defined transport format

• Multicast Channel ( MCH)

> Broadcasts in the entire coverage area of the cell;

> Supports MBSFN combining of MBMS transmission on multiple cells;

> Supports semi-static resource allocation e.g. with a time frame of a long cyclic prefix

• Downlink Shared Channel ( DL-SCH )

> Main channel for downlink data transfer. It is used by many logical channels.

> Supports Hybrid ARQ

> Supports dynamic link adaptation by varying the modulation, coding and transmit power

> Optionally supports broadcast in the entire cell; > Optionally supports beam forming

> Supports both dynamic and semi-static resource allocation

> Supports UE discontinuous reception (DRX) to enable UE power saving > Supports MBMS transmission

LTE Downlink Physical Channel

• Physical Downlink Shared Channel ( PDSCH)

>

This channel is used for unicast and paging functions > Carries the DL-SCH and PCH

> QPSK, 16-QAM, and 64-QAM Modulation

• Physical Downlink Control Channel ( PCSCH)

> Informs the UE about the resource allocation of PCH and DL-SCH, and Hybrid ARQ information related to DL-SCH

> Carries the uplink scheduling grant > QPSK Modulation

Uplink Physical Channels

• Physical HARQ Indicator Channel (PHICH)

>

Used to report the Hybrid ARQ status

> Carries Hybrid ARQ ACK/NAKs in response to uplink transmissions. > QPSK Modulation

• Physical Braodcast Channel (PBCH)

>

This physical channel carries system information for UEs requiring to access the network.

Uplink Physical Channels

• Physical Radio Access Channel ( PRACH)

>

for random access functions

• Physical Uplink Shared Channel ( PUSCH)

> Carries the UL-SCH

> QPSK, 16-QAM, and 64-QAM Modulation

• Packet Uplink Control Channel ( PUCCH)

> Sends Hybrid ARQ ACK/NAKs > Carries Scheduling Request (SR) > Carries CQI reports

Uplink Transport Channels

• Random Access Channel (RACH)

> Channel carries minimal information

> Transmissions on the channel may be loss due to collisons

• Uplink Shared Channel ( UL–SCH )

>

Optional support for beam forming > Support HARQ

Uplink Logical Channels

• Common Control Channel ( CCCH)

> Channel for transmitting control information between Ue and network.

> This channel is used for UEs having no RRC connection with the network.

• Dedicated Control Channel ( DCCH)

> A point-to-point bi-directional channel that transmits dedicated control information between a UE and the network.

> Used by UEs having an RRC connection.

• Dedicated Traffic Channel ( DTCH)

> A point-to-point channel, dedicated to one UE, for the transfer of user

information.

LTE FRAME STRUCTUR

> Functions

System can maintain synchronization and manage the different type of information that need to be carried between the eNodeB and UE

> LTE frame structure consist of 1. FDD ( Frequency division duplex) 2. TDD ( Time division duplex )

> A radio frame has duration of 10 ms

> A resource block spans 12 subcarriers over a slot duration of 0.5 ms > BW RB = 180 KHz

TDD Frame Structure

DwPTS : Downlink Pilot Time Slot GP : Guard Period

LTE TDD Sub Frame Allocations

D : sub frame for downlink transmission S :"special" sub frame used for a guard time U : sub frame for uplink transmission

Downlink Link Budget LTE

Unit Value Info

Data Rate kbps 1000 Transmitter - eNodeB a. Tx Power dBm 46 a b. Tx Antenna Gain dB 18 b c. Loss System dB 3 c d. EIRP dBm 61 a+b+c Receiver - UE e. Ue Noise Figure dB 7 e f. Thermal Noise dBm -102.7 k*T*B g. SINR dB -5 g

h. Receiver Sensitivity dBm -100.7 e+f+g i. Interference Margin dB 3 i j. Control Channel Overhead dB 1 j

k. Rx antenna gain dBi 0 k

l. Body Loss dB 0 l

MAPL dB 157.7 d-h-i-j+k-l

Propagation Model

• LTE – 700 MHz

– Okumura-Hatta

• LTE – 2100 MHz

– Cost 231-Hatta

• LTE – 2600 MHz

– SUI

M T R T c

p 46,3 33,9(logf ) 13,82logh a(h ) (44,9 6,55logh )logd C

L        (d/100) log 47.9 109.78 Lp  d log hB] log 6,55 – [44,9 CH -hB log 13,82 – f log 26,16 69,55 Lp  

Pathloss SUI

Lp = 109.78 + 47.9 log (d/100)

78

.

109

)

100

/

log(

9

.

47

d



Lp



9

.

47

/

)

78

.

109

(

)

100

/

log(

d



Lp



9 . 47 / ) 78 . 109 (

10

)

100

/

(

d



Lp 9 . 47 / ) 78 . 109 (

10

100





Lp

x

d

9 . 47 / ) 78 . 109 7 . 157 (

10

100





x

d

00042 . 1

10

100x

d



966

.

1000



d

meters

Radius Calculation

L = 2,6 d2

L = 1,95 . 2,6 . d2

Radius Calculation

L = 2,6 d2 L = 1,95 . 2,6 . d2 2

(1)

x

2.6

L



2.6

L



2

(1)

x

2.6

x

1.95

L



5.07

L



2

km

2

km

Number of eNodeB

• Urban Area (Trisector)

– total area 242.928

–

–

2

km

07

.

5

/

928

.

242



eNodeB

N

48



eNodeB

N

Calculation steps:

1. Number of user

2. User density

3. Services and Type

4. Penetration : building, vehicular, pedestrian

5. BHCA and call duration

6. OBQ

Number of User

Where:

• Un : num of user on year ‘n’

• Uo : initial num of user (based on urban/sub-urban) • a : percent of cellular user (%)

• b : penetration of operator A (%) • d : Percent of LTE user

• N : num of civilian in the object area • gf : num of user growth factor

• n : planned year

• u/sub : urban or sub-urban penetration (%)

Uo is Uo_u or Uo_sub Uosub = sub x UoN

Uo_u = u x UoN

Un = Uo (1 + gf)n

Customer Prediction Parameter

Ex :

• Population = 1445892 people • Cellular penetration = assumption 80% • LTE penetration = assumption 10 % • LTE provider A penetration = assumption 50 %

User prediction in 5th _years

• U5 = 57835 ( 1 + 0.05 )5 assumption fp=5%

= 73814 user

Population 1445892 people Customer cellular (80%) 1156713 user Customer LTE (10%) 115671 user Customer LTE provider A (50%) 57835 user

Example User Calculation

Ex :

• urban penetration

= assumption 60 %

• suburban penetration

= assumption 40 %

• Urban user = 73814 x 60 %

= 44288 user

User Density

• L

_u

: urban area wide

• L

_sub

: sub-urban area wide

• L

: object area wide

• C

_u

: Urban area density

• C

_sub

: sub-urban area density

L_u = L x u L_sub= L x sub

Example User Density Calculation

Ex :

• urban area penetration

= assumption 40 %

• suburban area penetration = assumption 40 %

• Openarea

= assumption 20 %

=>

Urban area wide (Lu) : 242,928 km2 Sub-urban area wide (Lsub) : 242,928 km2

=>

C_u = 44288 / 242,928 = 182,31232 user/km2

Services and Type

• Services (Rb)

– VoIP

: 64 kbps

– FTP

: 1000 kbps

– Video : 384 kbps

• Type (c)

– Building

: 50 %

– Vehicular

: 30 %

– Pedestrian

: 20 %

• Penetration (p) per type per service

e.g:

BUILDING VoIP usage penetration = 0.5

BUILDING FTP usage penetration = 0.4

PEDESTRIAN Video usage penetration = 0.3

• BHCA (B) per type per service

e.g:

BUILDING VoIP usage penetration = 0.008

BUILDING FTP usage penetration = 0.009

PEDESTRIAN Video usage penetration = 0.008

• Call duration (h) per type per service (ms)

e.g:

BUILDING VoIP usage penetration = 60

BUILDING FTP usage penetration = 50

service net user bit rate (Rb) VoIP 64000

FTP 1000000 Video 384000 type call duration (h)

voip video ftp

building 60 40 50

pedestrian 60 50 70

vehicular 60 40 80

BHCA (B)

Service Building Pedestrian Vehicular Voip 0,008 0,008 0,009 Video 0,007 0,008 0,009 FTP 0,009 0,008 0,008

Penetrasi User (p)

Building Pedestrian Vehicular Voip 0,5 0,5 0,2

Video 0,3 0,3 0,2

OBQ (Offered Bit Quantity)

• VoIP

OBQ

_T

= c

_T

x C

_{u; T}

x p

_T

x Rb

_VoIP

x B

_T

x h

_T

• FTP

OBQ

_T

= c

_T

x C

_{u; T}

x p

_T

x Rb

_FTP

x B

_T

x h

_T

• Video

OBQ

_T

= c

_T

x C

_{u; T}

x p

_T

x Rb

_Vid

x B

_T

x h

_T

Note: if T= pedestrian, then “OBQ

_T

“ is pedestrian OBQ, “B

_T

“ is

pedestrian BHCA, etc.

OBQ cont’d

Where:

OBQ

_VoIP

= OBQ

_vehicular

+ OBQ

_building

+ OBQ

_pedestrian

OBQ

_FTP

= OBQ

_vehicular

+ OBQ

_building

+ OBQ

_pedestrian

OBQ

_Video

= OBQ

_vehicular

+ OBQ

_building

+ OBQ

_pedestrian

OBQ

_total

= 20,74860049 + 13,97825 + 8,260936 =

42,98779

OBQ

Service Building Pedestrian Vehicular Voip 1,400158616 0,5600634 0,252029 Video 2,940333094 5,2505948 1,008114 FTP 16,40810878 8,1675919 7,000793 ∑ 20,74860049 13,97825 8,260936

eNodeB Capacity

ms

N

x

xN

Hz

bit

Mbps

e

PeakBitRat

_subcarriers symbol per subframe

1

]

[



  Bandwidth (MHz) Modulation QPSK 16 QAM 64 QAM 1.4 2.016 Mbps 4.032 Mbps 6.048 Mbps 3 5.04 Mbps 10.08 Mbps 15.12 Mbps 5 8.4 Mbps 16.8 Mbps 25.2 Mbps 10 16.8 Mbps 33.6 Mbps 50.4 Mbps 15 25.2 Mbps 50.4 Mbps 75.6 Mbps 20 33.6 Mbps 67.2 Mbps 100.8 Mbps

Site Calculation

• Site (L)

L

= (50.4 x 3) / OBQtotal

= (50.4 x 3) / 42,98779 = 3,5172778

km2

• Radius (d)

d

= (L / 2.6 / 1.95) ^ 0.5

= (3,5172778 / 2.6 / 1.95) ^ 0.5 = 0,832912489 km

Site Calculation Con’t

• Number of eNodeB (M)

M =

Lu

/ L

= 242,928 km

2

/ 3,5172778 km

2

= 69,06704366

We use “Lu” JUST IN CASE we count urban capacity only

Getting Started with Atoll

New -> From a Document Template Choose LTE workspace

Setting Project Area

It is used to display the project area from the map raster.

To set the

coordinate type and the area displayed on the worksheet.

Import Raster Map

raster is a contour map based on the topography of the area. Raster

consist of clutter map, height map and vector map

Import Raster Map Con’t

Clutter index -> Clutter Classes Height index -> Altitude Vector index -> Vectors

Frequency Band

frequency bands and can be seen in the LTE specification 3GPP.org

Antenna Polarization Model

add the appropriate antenna used

Setting Feeder

To setting feeder & connector loss at eNode B equipment

Setting Transmitter Frequency Band

after determining the frequency band, set the transmitter

frequency as the frequency and morpho class used

Environtment

Delete user

Delete User Profile

Delete service then setting service type

Services

Delete service then

Service

Add User Profile

Add User Profile

Pedestrian

Plotting eNode B

eNode B can be in place based on

planning calculation or the use of existing nodeB or BTS

Make a Prediction

make predictions based on

measured

fill of the receiver sensitivity

specification Click calculate

Reference

[1] Abdul Basit, Syed. Dimensioning of LTE Network Description of

Models and Tool, Coverage and Capacity Estimation of 3GPP

Long Term Evolution radio interface. 2009.

[2] Coverage

and

Capacity

Dimensioning

Recommendation:

Ericsson. 2009.

[3] Holma, Harri and Antti Toskala. WCDMA for UMTS – HSPA

Evolution and LTE. John Willey and Son: 2007.