A-LTE

ATOLL LTE FEATURES

Training Program

1. LTE Concepts

2. LTE Planning Overview

3. Modelling an LTE Network

4. LTE Predictions

5. MIMO Modelling

6. Neighbour Allocation

7. Automatic Resource Planning

8. Frequency Plan Analysis

9. Monte-Carlo Based Simulations

10. Using Drive Tests

11. Terminology and Concepts

© Forsk 2009 Slide 2 of 149Confidential – Do not share without prior permission

1. LTE Concepts

Context and background

OFDM/OFDMA basics


Context and Background

What is LTE?

What is 4G?

Why LTE?

LTE deployment

RF planning/optimisation tool requirements for LTE

Evolution of LTE


What is LTE?

LTE = Long Term Evolution

3GPP1’s project name for Evolved UTRA2 (e-UTRA)

Next generation of 3GPP-based mobile networks(GSM/GPRS/EDGE, UMTS/HSPA, and TD-SCDMA)

One of the 3 standards on which 4G cellular networks will be based

LTE from 3GPP

WiMAX from IEEE and the WiMAX Forum

UMB3 from 3GPP2

1 Third Generation Partnership Project

2 UMTS Terrestrial Radio Access

3 Ultra Mobile Broadband


What is 4G?

Provides improvements over existing 2G and 3G networksHigh data rates at high mobile speeds:~100Mbps in DL, 50Mbps in UL with MIMO

Inter-working and support for mobility:Handovers to 3G and 2G layers and roaming

Service and content convergence:VoIP, download, streaming, TV, VOD, etc.

All IP backbone

Based on some form of OFDM

Implement smart antenna/MIMO techniques

Use higher order modulation techniques

Support for scalability: Channel bandwidth adaptation


What is 4G?

Evolution of Mobile Technologies

200820072006 2009

3G LTE

All-IPOFDM MIMO AAS

WiMAX 802.16m

All-IP OFDM MIMO

WiMAX 802.16e-2005

All-IPOFDM MIMOAAS AAS

CDMA2000 EV-DO Rev.A

IP transport

EV-DO Rev.C

All-IPOFDM MIMO AAS

HSDPA / HSUPA

IP Transport

HSPA+

MIMO All-IP

EDGE Evolution


What is 4G?

Evolution of 3GPP StandardsRelease ’99: UMTS FDD

Release 4: UMTS TDD + FDD Repeaters

Release 5: HSDPA

Release 6: HSUPA (Enhanced Uplink) + MBMS

Release 7: HSPA+ (2x2 MIMO, Higher Order Modulation, etc.)

Release 8: LTE FDD and TDD


Why LTE?

Huge potential market shareGSM (80.4 % market share)Around 670 operators in ~200 countriesMore than 3 billion subscribers worldwide

UMTS HSPA (7.8 % market share)Around 105 operators in ~47 countriesNearly 300 million subscribers worldwide

Potential market share for UMB: 11 %

EconomicPossibility to reuse part of existing 3Gequipment hardware with software defined radio

Spectrum already allocated to operators

Convergence of market and user needsMulti-play services (voice, data, broadcast, …)

Number of mobile subscriptions worldwide: > 3.8 billion


Improvements over 3G (UMTS HSPA)

Why LTE?

Data RatesData RatesDL: 14.4 Mbps &DL: 14.4 Mbps &

UL: 5.7 MbpsUL: 5.7 Mbps

Highly sensitive toHighly sensitive toInter-symbol InterferenceInter-symbol Interference

Highly sensitive toFrequency Selective

Fading

Min 5 MHzMin 5 MHzSpectrumSpectrumLTE vs. 3GLTE vs. 3G

OrthogonalSubcarriers

Cyclic Prefix

Up to 100 Mbps DL and 50 Mbps UL

Min 1.4 MHz


LTE Deployment

1st phase:A few trial sites in urban areas where provision of high data rate services has market potential

Site locations probably the same as existing 3G sites

Spectrum sharing with existing 3G cell (1 carrier dedicated to the trial LTE layer)

2nd phase:Replacement of 3G sites with on-air LTE sites, or

Co-existence of 3G and LTE coverage layers

High Speed High ThroughputHandovers


Migration from any 3GPP technology to LTE

Rational choice for GSM and GSM/UMTS operators

Some CDMA operators might also opt for LTE instead of UMB

Very few GSM operators would opt for WiMAX

Rarely any green-field scenarios

LTE Deployment

GSM UMTSGPRSEDGE

HSPA LTE

Non-3GPPTechnologies


Evolution of LTE

Future: IMT-AdvancedMost 4G networks will move to

• LTE Advanced• WiMAX 802.16m

100 Mbps to 1 Gbps in DL• 100 Mbps for fast moving users• 1 Gbps for slow to stationary users


OFDM/OFDMA Basics

OFDM definition and differences between FDM and OFDM

Advanced OFDM : OFDMA

Multiple access techniques and duplexing methods

Benefits of OFDM/OFDMA

OFDM/OFDMA in LTE


What is OFDM ?

OFDM = Orthogonal Frequency Division MultiplexingAlso known as Discrete MultiTone (DMT) or Multi-Carrier Modulation (MCM)

Advanced form of Frequency Division Multiplexing (FDM)• FDM : single modulated radio signal per user

• OFDM : hundreds to thousands of separate radio signals (subcarriers) spread across a wideband channel. In OFDM, the sub-carrier frequencies are chosen so that the subcarriers are orthogonal to each other

Time period for modulation: OFDM symbol• Adjustable guard periods : cyclic prefix used to dissipate multipath effect

• Symbol rate = f(channel bandwidth, carrier spacing - Distance between subcarriers)


OFDM Frequency and Time Domains

1 OFDM symbol

Fre

qu

en

cy

Su

bca

rrie

rs

Symbols

Time


Differences between FDM and OFDM

FDM (Frequency Division Multiplexing)

Carriers separated by guard bands low spectrum usage efficiency

More carriers more guard bands decrease in efficiency

Therefore, usually large carrier widths are used

Large carrier widths low symbol duration (f=(1/t)) more sensitive to time delays


Differences between FDM and OFDM

OFDM (Orthogonal Frequency Division Multiplexing)

Narrowband orthogonal carriers negligible inter-carrier-interference (ICI)

Long symbol durations + cyclic prefix negligible inter-symbol-interference (ISI)

No ICI and ISI no intra-cell interference

Possibility to support less robust modulations like 64QAM, 16QAM, … for higher throughput

Centre point of subcarrier c intersects with subcarriers c-1 and c+1 at their 0 values


Advanced OFDM : OFDMA

OFDMA : Orthogonal Frequency Division Multiple Access

OFDMEach user is allocated the full channel : capacity wasting

OFDMAEach user can be assigned only a part of the entire channel at a time

Ability to subdivide the subcarrier population : more than one user served at a time

Su

bch

ann

els

Su

bch

ann

els

Su

bch

ann

els

Su

bch

ann

els


Benefits of OFDM/OFDMA

Negligible inter-carrier-interference (ICI)Thanks to orthogonal subcarriers which can be transmitted by the use of Fast Fourier Transform (equipment evolution)

Use of less robust modulation Increased data rate

Improved resilience (ISI)Sending data across parallel carriers lower rate/carrier

Fewer modulation symbols longer symbol duration• Better chance to correctly sample signal

Efficient usage of the spectrum

Better resistance to frequency selective fading channel

Multiple access (time and frequency multiplexing techniques)


Multiplexing and Duplexing

Uses SOFDMA (same as WiMAX 802.16e) in DLSOFDMA: Scalable Orthogonal Frequency Division Multiple Access

Uses SC-FDMA in UL (an OFDM variant not much different from SOFDMA)SC-FDMA: Single-Carrier Frequency Division Multiple Access

Can be deployed in FDD and TDD


Multiple Access Techniques

1g1g 2g2g

3g3g4g4g


OFDM and OFDMA

Orthogonal Frequency Division Multiple AccessProvides resource allocation flexibility

Scalable OFDMAChannel bandwidth is scalable, i.e., can be adapted as needed

© Forsk 2009 Confidential – Do not share without prior permission Slide 23 of 149

3

5

10

15

20

Bandwidth (MHz)

1.4

LTE Channel Structure

OFDMA in DL and SC-FDMA in ULA channel is composed of more than 1 Frequency Block (FB)

• Equivalent of Subchannel in WiMAX• Fixed width = 180 kHz (LTE system level constant)• 1 Frequency Block over 1 slot = 1 Resource Block (RB) (Elementary unit assigned to 1 user)• Benefit of SC-FDMA: Low Peak-to-Average Power Ratio (PAPR) Easier UE Design

Each FB is composed of many Subcarriers• Two Subcarrier widths possible: 15 kHz, 7.5 kHz• 1 FB = 12 SCa of 15 kHz OR 24 SCa of 7.5 kHz• 7.5 kHz specified for MBMS/SFN services

• Narrow subcarrier width Longer symbol duration + Longer Cyclic Prefix = More resistant against multipath


LTE Channel Structure

SpectrumAllocation

SubcarrierSpacing

SamplingFrequency

FFT SizeNumberof RBs

Number ofUsed Subcarriers

1.4 MHz

15 kHz(7.5 kHz

for MBMS)

1.92 MHz(1/2 x 3.84)

128 6 72 (73)

3 MHz3.84 MHz(1 x 3.84)

256 15 180 (181)

5 MHz7.68 MHz(2 x 3.84)

512 25 300 (301)

10 MHz15.36 MHz(4 x 3.84)

1024 50 600 (601)

15 MHz23.04 MHz(6 x 3.84)

1536 75 900 (901)

20 MHz30.72 MHz(8 x 3.84)

2048 100 1200 (1201)


TDD and FDDSpecific frame structures for TDD and FDD

1 frame = 10 ms = 2 half-frames (TDD) = 10 subframes or TTI (each 1 ms) = 20 slots (each 0.5 ms)

1 slot (0.5 ms) = 6 or 7 symbol durations

Control channels transmitted on subframes 0 and 5 (always DL)

Two possible cyclic prefix durations: Normal or Extended (resp. 7 or 6 OFDM symbols per slot)

LTE Frame Structure

LTE Frame

10 ms

SF 0 SF 1 SF 9……………………………..

1 ms

Slot 0 Slot 1 Slot 2 Slot 3Slot 18…………………………….. Slot

19

0.5 ms


LTE Frame Structure

FDD Frame

TDD Frame with (DwPTS, GP, and UpPTS as in TD-SCDMA)Full- and Half-frame switching point periodicity

Half-frame periodicity provides the same half-frame structure as a TD-SCDMA subframe


FDD Frame = 10 ms

0 2 3 4 5 7 8 9

1 ms

61

Subframe

TDD Frame = 10 ms (with SPP = ½ Frame) Half frame = 5 ms

0 2 3 4 5 7 8 9

DwPTS UpPTSGP DwPTS UpPTSGP

1 msSubframe

TDD Frame = 10 ms (with SPP = Frame) Half frame = 5 ms

0 2 3 4 5 7 8 9

DwPTS UpPTSGP

6

1 msSubframe

eNode-B

Physical Channels

Primary-SCH

Secondary-SCH

Physical Downlink Shared Channel

Common Control Physical Channel

Physical Downlink Control Channel

Physical Random Access Channel

Physical Uplink Shared Channel

Physical Uplink Control Channel

HARQ feedbackCQI reporting

UL scheduling requestCQI reporting for MIMO

related feedback

Random access

Traffic

Slot/Frame synchronization &

Cell Id identification

Traffic, MBMSControl information

Paging

HARQ feedbackTransport format

UL scheduling grantResource allocation


Control and Traffic Channels

BCCH PCCH CCCH DCCH DTCH MCCH MTCH

BCH PCH UL-SCHDL-SCH MCH RACH

PBCH PUSCHPDSCH PMCH PRACHPUCCH

Transport

Logical

Physical

DL TCH UL TCH


OFDMA LTE Frame (DL)

Structure of a Resource BlockFrame structure of Type I, 1 antenna, ΔF = 15 kHz

• Standard frequency block

• Any frequency block within the centre 6 frequency blocks:

Legend:Downlink Reference Signals

PBCH

P-SCH

S-SCH

PDCCH / PHICH / PCFICH

DL-SCH

Subcarriers in a resource block are adjacent

RBs allocated to mobiles are not necessary adjacent Interference Coordination


OFDMA LTE Frame (DL)

OFDMSymbol 0

OFDMSymbol 1

OFDMSymbol 3

OFDMSymbol 4

OFDMSymbol 5

OFDMSymbol 6

OFDMSymbol 2

Legend:

Downlink Reference signals

PBCH

P-SCH

S-SCH

PDCCH / PHICH / PCFICH

DL-SCH

P-SCH and S-SCH ~ Preamble in WiMAXDL Reference signals ~ Pilot subcarriers in WiMAX

1 subframe = 2 slots (1 ms)

1 frame = 10 subframes (10 ms)

SF 0 SF 1 SF 2 SF 3 SF 4 SF 5 SF 6 SF 7 SF 8 SF 9

7 OFDM symbols at normal CP per slot (0.5 ms)

0 1 2 3 4 5 6 0 1 2 3 4 5 6


SC-FDMA LTE Frame (UL)

OFDMSymbol 0

OFDMSymbol 1

OFDMSymbol 3

OFDMSymbol 4

OFDMSymbol 5

OFDMSymbol 6

OFDMSymbol 2

Legend:

Uplink Demodulation Reference Signal

Uplink Sounding Reference Signal

PUCCH

Demodulation Reference Signal for PUCCH

1 subframe = 2 slots (1 ms)

1 frame = 10 subframes (10 ms)

SF 0 SF 1 SF 2 SF 3 SF 4 SF 5 SF 6 SF 7 SF 8 SF 9

7 OFDM symbols at normal CP per slot (0.5 ms)

0 1 2 3 4 5 6 0 1 2 3 4 5 6


Cell Search/Synchronisation

eNode-B

72 subcarriers

Sub-carriers for data

SCH in 1.25 MHz/72 subcarriers

BCH in 1.25 MHz/72 subcarriers

1.4/3/5/10/15/20 MHz spectrum

1.25 MHz spectrum

BCH informationreception

UE SCH detection over a

1.4/3/5/10/15/20 MHz spectrum

Detect spectrum centre and 1.25 MHz

spectrum

SCH and BCH frequency reception

Data transmission on assigned spectrum provided by System

Information

SCH and BCH band


Usual 1x3x1 and 1x3x3 allocations

Fractional Frequency Allocation: like segmentation in WiMAXPossibility to allocate 3 fractions of the a channel to 3 sectors of a site

Provides better spectrum usage and interference reduction

Frequency Planning

F1 F2 F3

Frequency

F1

F1 F1 F2F3

F1

F1

Seg 2 Seg 3Seg 1Seg1

Seg 3 Seg 2

Seg1

Seg 3 Seg 2

F1

F1 F1


Handovers in LTE

Hard handover

Fast BS Selection

No soft handover specified for LTE


MIMO Systems in LTE

Multiple Input Multiple Outputs (MIMO) systemsStations and user equipment can support MIMO systems

• Numbers of transmission and reception antenna ports at the transmitter and user equipment

Supported MIMO systems: • Transmit or Receive Diversity (Tx/Rx Div)

• More than one transmission antenna to send the same data• Improvement of CINR

• Single-user MIMO or spatial multiplexing (SM)• More than one transmission antenna to send different data streams on each antenna• Improvement of throughput for a given CINR

• Adaptive MIMO switch (AMS)• Technique to switch from SM to Tx/Rx Diversity as CINR conditions get worse than a given

threshold

• Multi-user MIMO or collaborative MIMO• Multiplexing of several users with good enough radio conditions• More than one cell reception antenna to receive transmissions from several users over the

same frequency-time allocation (UL only)• Can be used with single-antenna user equipment• Improvement of UL capacity in terms of number of connected users


Training Program

1. LTE Concepts



4. LTE Predictions

5. MIMO Modelling









LTE features supported in Atoll

LTE workflow in Atoll


LTE Features supported in Atoll

Supports Evolved UTRA (3GPP Release 8 LTE) NetworksVarious frequency bands

Scalable channel bandwidths

Resource blocks per channel and sampling frequencies

Support of TDD and FDD frame structures

Half-frame/full-frame switching point periodicities for TDD

Normal and extended cyclic prefixes

Downlink and uplink control channels and overheads• Downlink and uplink reference signals, P-SCH, S-SCH, PBCH, PDCCH, PUCCH, etc.

Physical cell IDs

Possibility of fixed subscriber database for fixed applications

Support of directional CPE antennas© Forsk 2009 Slide 39 of 149Confidential – Do not share without prior permission

LTE Features supported in Atoll

Supports Evolved UTRA (3GPP Release 8 LTE) NetworksSignal level based coverage planning

CINR based coverage planning

Network capacity analysis using Monte Carlo simulations

Scheduling and resource allocation in two-dimensional frames

Multiple Input Multiple Output (MIMO) systems• Transmit and Receive Diversity• Single-User MIMO or spatial multiplexing • Adaptive MIMO Switch (AMS)• Modelling of Multi-User MIMO (collaborative MIMO – UL only)

Tools for resource allocation• Automatic allocation of neighbours and physical cell Ids• Automatic allocation of frequencies (AFP) (Optional)

Network verification possible using test mobile data


LTE Workflow in AtollLTE Workflow in Atoll

Open an existing project or create a new one

Prediction study reports

Traffic maps

Network configuration- Add network elements- Change parameters

User-defined values

Automatic or manual neighbour allocation

Basic predictions(Best server, signal level)

Monte-Carlo simulations

Signal quality and throughput predictions

Cell load conditions

Subscriber lists

And/or

Frequency plan analysis

Automatic or manual frequency planning

Automatic or manual physical cell ID planning


Training Program

1. LTE Concepts



4. LTE Predictions

5. MIMO Modelling









Frequency bands

LTE Frame structure settings

Transmitter parameters

Cell parameters


Frequency bandsAtoll can model multi-band networks within the same document

TDD (Time Division Duplexing) or FDD (Frequency Division Duplexing)

One frequency band assigned to each cell

Frequency Bands


Transmitter folder global parameters

System-level constants (Hard-coded)• Width of a resource block (180 kHz)• Frame duration (10 ms)

Other control channel overheads defined by 3GPP (calculated based on 3GPP specs)• Reference signals, P-SCH, S-SCH, PBCH, etc.

LTE Frame structure settings

Number of SD for Physical Downlink Control Channel

(0,1,2 or 3) carrying DL and UL Resource

allocation information

Normal (default) or extended cyclic prefix (No. of SD per slot)

e.g.: at 15 kHz, 7 SD/slot (normal) or 6 SD/slot

(extended)

Average number of resource blocks for Physical Uplink Control Channel (top

and bottom of frame transmitted every 2 slots)

TDD option only : Switch from DL to UL every half frame (default) or every

frame


Transmitter Parameters

Equipment specifications

DL and UL total losses, noise figure

Cells: (Tx-carrier) pairsSpecifications of carriers in a

transmitter

MIMO (Multiple Input Multiple Output systems)

reception and transmission settings


Cell Parameters

Inputs of the neighbour allocation algorithm

Neighbour list

UL/DL traffic loads*

Cell activity

Power and energy offsets from computed

reference signal

Cell’s frequency band

Channel number in the frequency band (and

allocation status)

LTE equipment used for bearer selection/quality

indicator studies/MIMO gains

UL noise rise due to surrounding mobiles*

Maximum simultaneous users supported by the cell*

Physical Cell ID ( and allocation status)

Frame configuration (TDD only)

Threshold to switch from SM to Tx/Rx Div or

for using MU-MIMO

Reference signal quality threshold used as cell

coverage limit

Scheduler used for bearer selection and resource allocation

Cell order used for carrier selection

Resource allocation min reuse distance

Cell capacity gain in case of MU-MIMO

Effect of external sources of interferences

Max UL and DL traffic loads to be respected

during simulations

* User-defined or simulation output

UL and DL MIMO support (Tx/Rx Div, SU-MIMO/SM,

AMS and/or MU-MIMO)


Training Program

1. LTE Concepts



4. LTE Predictions

5. MIMO Modelling








4. LTE Predictions

Introduction

Parameters used in predictions

Prediction settings

Fast link adaptation modelling

Coverage prediction examples

Point analysis studies


Introduction

Coverage predictionsGeneral studies based on downlink reference signal levels

• Best server plot based on downlink reference signal levels• Multiple server coverage based on downlink reference signal levels• Reference signal signal level plots• Reference signal CNR plots

LTE UL and DL specific studies• SCH/PBCH, PDSCH, and PUSCH signal level plots• SCH/PBCH, PDSCH, and PUSCH CNR plots• Quality studies (reference signal, SCH/PBCH, PDSCH, and PUSCH CINR and interference plots)• Best bearer plots based on PDSCH and PUSCH CINR levels• Throughput and cell capacity per pixel plots based on PDSCH and PUSCH CINR levels

• Peak RLC, effective RLC, and application throughputs• Peak RLC, effective RLC, and application cell capacities• Peak RLC, effective RLC, and application aggregate cell throughputs

Point predictions


Introduction

Principles of the studies based on traffic

Study calculated for

• Given load conditions• UL noise rise• DL traffic load

• A non-interfering user with• A service• A mobility• A terminal type with a directive antenna (oriented towards the serving cell)


Load Conditions

Load conditions are defined in the cells table

Values taken into consideration in predictions for each cell


Service Properties

Parameters used in predictionsHighest bearers in UL and DL

Body loss

Application throughput parameters


LTE Bearer Properties

Support for multiple modulation and coding schemes (MCS)User-selectable modulations (QPSK, 16QAM, and 64QAM)

User-definable coding rates (e.g. 1/2, 2/3, 3/4, etc.)

User-definable bearer efficiencies (useful bits per resource element)• Used for channel throughput evaluation


LTE Bearer Properties

Link adaptation in LTE


Mobility Properties

Parameters used in predictionsMapping between mobilities and thresholds in bearer and quality indicator determination (as radio conditions depend on user speed).


Terminal Properties

Parameters used in predictionsReception equipment

Antenna settings (incl. MIMO support)

Maximum terminal power

Gain and losses

Noise figure

Support of MIMO

Number of Antenna ports in UL and DL in case of MIMO

support


Prediction Settings

Coverage prediction plots

Do not require Monte-Carlo simulations or subscriber lists

Reference signal, SCH/PBCH, PDSCH, and PUSCH signal level plots• Best server plot

• Coverage by signal level

• Multiple server coverage

Preamble signal quality based coverage predictions• Selection of a mobility, a service, a terminal (possibly directional antenna oriented towards the serving

cell)

• Reference signal, SCH/PBCH, PDSCH, and PUSCH CNR plots


Prediction Settings

Coverage prediction plots

Traffic channel CINR based coverage predictions• Based on user-defined cell loads or on Monte-Carlo simulation results

• Selection of a mobility, a service, a terminal (possibly directional antenna oriented towards the serving cell)

• Reference signal, SCH/PBCH, PDSCH, and PUSCH CINR and interference plots

• Best bearer plots based on PDSCH and PUSCH CINR levels

• Throughput and cell capacity per pixel plots based on PDSCH and PUSCH CINR levels• Peak RLC, effective RLC, and application throughputs• Peak RLC, effective RLC, and application cell capacities• Peak RLC, effective RLC, and application aggregate cell throughputs


Fast Link Adaptation Modelling

Atoll determines, on each pixel, the highest bearer that each user can obtainNo soft handover

Connection to the best server in term of reference signal level (C)

Bearer chosen according to the radio conditions (PDSCH and PUSCH CINR levels)

Process : prediction done via look-up tables

Reference signal quality evaluation (C)

Best server and service area determination (C/N)

PDSCH and PUSCH CINR calculation

Highest bearer determination limited by the

service settings

Peak RLC, effective RLC, and application throughput

calculation

Quality indicator (BER, BLER)


Interference Estimation

Atoll calculates PDSCH and PUSCH CINR according to:The victim traffic (PUSCH or PDSCH) power

The interfering signals impacted by:• The interferer powers• The path loss from the interferer to the victim• Antenna gain• Losses from interferer (incl. Shadowing effect and indoor losses)

The interference reduction due to the co and adjacent channel overlap between the studied and the interfering base stations

The interference reduction factor due to interfering base station’s traffic load


Bearer Selection

When PDSCH and PUSCH CINR are evaluated, the bearer is selected according to:The LTE reception equipment defined at reception (cell for UL, terminal for DL)

The CINR threshold to access each bearer

Scheduler parameters of the serving cell• Bearer selection criterion• The uplink bandwidth allocation target

The highest possible bearer according to the service settings


Bearer Selection

Scheduler settings for bearer determination

Bearer selection criterion: • Bearer index: selection of the highest bearer index

• Peak RLC throughput: selection of the highest peak RLC throughput

• Effective RLC throughput: selection of the highest effective RLC throughput

Uplink bandwidth allocation target:• Full bandwidth: use of all the frequency blocks

• Maintain connection: number of frequency blocks reduced one by one to increase the PUSCH CINR so that the mobile is able to get at least the lowest

bearer (as defined by the bearer selection criterion)• Best bearer: number of frequency blocks reduced to increase the PUSCH

CINR so that the mobile is able to get the best bearer available (as defined by the bearer selection criterion)


Throughput Estimation

When the bearer is selected, the channel throughput is calculated according to:The channel bandwidth and the sampling frequency

The frame definition considering hard coded parameters and user-defined ones (global parameters tab or the Transmitter folder property box).

The cyclic prefix ratio

The bearer efficiency defined in the selected bearer


Quality Indicator Estimation

When the bearer is selected, the quality indicator (BER or BLER) is obtained according to:The graphs defined in the quality graph tab of the receiver equipment

The selected bearer

The calculated PDSCH and PUSCH CINRs

The terminal mobility (optionally)


Prediction Examples (General Studies)

Coverage by signal level

(Based on reference signal power)

Number of servers

(Based on reference signal power)


Prediction Examples (Dedicated Studies)

Coverage by PDSCH CINR

(Isotropic receiver antenna)

Coverage by PDSCH CINR

(Directional receiver antenna)


Prediction Examples (Dedicated Studies)

Coverage by PUSCH CINR

(Isotropic receiver antenna)

Coverage by PUSCH CINR

(Directional receiver antenna)


Point Analysis Tool

Radio reception level at a given point : Reception tab

Select the reception tab in the point analysis window

In the tool bar, click

Define receiver settings

Display preamble signal levels

Reference signal levels


Point Analysis Tool

Radio reception diagnosis at a given point : Signal Analysis tab

Choice of UL&DL load conditions : if (cells table) is selected

Analysis based on DL load and UL noise rise from cells table

Definition of a user-definable “probe" receiver, indoor or

not

Received reference signals (best server on

the top)

Analysis detail on reference signals,

PDSCH and PUSCH

SCH/PBCH, reference signals,

PDSCH and PUSCH

availability (or not)


Training Program

1. LTE Concepts



4. LTE Predictions

5. MIMO Modelling








5. MIMO Modelling

Overview

MIMO settings in Atoll

MIMO Modelling in computations

Predictions examples


MIMO Modelling Overview

Base stations and user equipment support MIMO systemsGains graphs available in reception equipment

Numbers of transmission and reception antenna ports at base station and terminal

Antenna diversity modes in Atoll LTEMultiple Input Multiple Outputs (MIMO) systems

• Transmit/Receive Diversity (also called Space-Time Coding (STC) or Matrix A MIMO in other standards)• More than one transmission antenna to send the same data• Improvement of CINR Higher bearer Higher throughput• Usually used in coverage areas with bad CINR conditions

• Single-User MIMO (SU-MIMO) or Spatial Multiplexing (SM) (also called Matrix B MIMO in other standards)• More than one transmission antenna to send different data streams on each antenna• Improvement of throughput for a given CINR• Usually used in coverage areas with good CINR conditions

• Adaptive MIMO Switch (AMS)• Technique to switch from SM to Tx/Rx Diversity as CINR conditions get worse than a given

threshold


MIMO Modelling Overview

Antenna diversity modes in Atoll LTE (Cont’d)Multiple Input Multiple Outputs (MIMO) systems

• Multi-User MIMO or collaborative MIMO• Multiplexing of several users with good enough radio conditions• More than one cell reception antenna to receive transmissions from several users over the

same frequency-time allocation (UL only)• Can be used with single-antenna user equipment• Improvement of UL capacity in terms of number of connected users


MIMO Settings in Transmitters

MIMO (Multiple Input Multiple Output systems)

reception and transmission settings


MIMO Settings in Cells

Definition of the MIMO support type (STTD/MRC

(Transmit or Receive Diversity), SU-MIMO (SM),

AMS or MU-MIMO – UL Only)

Minimum reference signal C/N used as :

- threshold to switch from SU-MIMO to Tx/Rx Diversity

- Minimum required for using MU-MIMO

Uplink capacity gain due to MU-MIMO. The cell capacity is multiplied by this gain at pixels where MU-MIMO is

used


MIMO Settings in Terminals

Support of MIMO

Number of Antenna ports in UL and DL in case of MIMO support

Reception equipment defining SU-MIMO and

diversity gains


Transmit and Receive Diversity Settings

Diversity gain depending on the MIMO configuration

Additional Diversity gain per clutter class (DL and UL)

Sum of the gains applied on PDSCH/PUSCH CINR© Forsk 2009 Slide 78 of 149Confidential – Do not share without prior permission

SU-MIMO Settings

Maximum possible gain in channel capacity

SU-MIMO gain factor per clutter class

MIMO throughput = SISO throughput (1 + SU-MIMO gain factor (max MIMO gain – 1))© Forsk 2009 Slide 79 of 149Confidential – Do not share without prior permission

MIMO Modelling in Computations

Predictions and simulationsOn each pixel, a receiver is connected to its best server (in term of reference signal C/N)

MIMO is possible if :• MIMO settings are defined in the LTE equipment selected at the cell – for UL – (or terminal – for DL –)

level

• The support of any MIMO mode (Tx/Rx diversity, SM, AMS, SU-MIMO) is defined for to the serving cell

• MIMO is supported by the user’s terminal

• The calculated reference signal C/N exceeds the reference signal C/N threshold


Prediction Examples (MIMO Effect)

Coverage prediction examples (MIMO system)

Coverage by DL CINR

(Without MIMO)

Coverage by DL CINR

(MIMO with 2*2 antenna)

CINR improved for low values (due to Tx/Rx

diversity)


Training Program

1. LTE Concepts



4. LTE Predictions

5. MIMO Modelling









Importing existing neighbour relationships

Neighbour automatic allocation

Neighbour graphical display

Modifying neighbour relationships manually

Exporting neighbour relationships


Importing Existing Neighbour Relationships

Possibility to copy/paste or to import a list of neighboursIntra-carrier and inter-carrier neighbours are mixed in the same table

PrerequisitesA text file with at least 2 columns

• Source cells and neighbour cells• Relationships must be defined between atoll format cell names


Importing Existing Neighbour Relationships


Neighbour Automatic Allocation (1/4)

Possibility to define neighbourhood constraints to be considered during the automatic neighbour allocation

Allocation parametersMaximum number of neighbours

• Global value for all the transmitters or value specified for each transmitter

Maximum inter-site distance

Allocation strategy based on the overlapping of cell coverage

List of neighbourhood relationships you may force or forbid



Coverage conditions

Overlapping criterion

Calculation options

Do not select the option if you want to keep existing

neighbours

Start allocation



Overlapping criterion % min covered area is defined by the formula : (SA ∩ SB) / SA where :- SA is the coverage area of a restricted by ho start and ho end- SB is the best server area of cell B

Best reference signal level cell B (candidate)

Best reference signal level cell A (reference)

Cell A

Cell B

Reference signal threshold (from reference signal

quality threshold)

Handover start

Handover end

Best server area

Best server area



Allocation resultSorted list of neighbours with allocation reasons and importance value (0-1)

Commit selected neighbours only

Allocation results

Sort and filtering tools


Neighbour Graphical Display

Display of neighbourhood links on the map

Calculate a “coverage by transmitter” and display it on the map

Select the icon in the toolbar and click a transmitter on the map

Inwards link: site23_1(0) is neighbour of site22_0(0)

Symmetric link: site17_1(0) is neighbour of site23_1(0) and

vice-versa

Outwards link: site27_0(0) is neighbour of site23_1(0)

Neighbourhood relationships of site23_1(0)


Neighbour Graphical Display

Possibility to display neighbour characteristics on the mapCalculate a “coverage by transmitter” and display it on the map

Display neighbour relationships of the desired transmitter

Click the icon from the toolbar


Modifying Neighbour Relationships Manually

Possibility to add/remove neighbour relationships on the map using the ctrl and shift shortcuts

For intra-carrier neighbourhood links only

Possibility to add/remove neighbours in the cell property dialogue Neighbour list of site5_2(0)

List of transmitters within a 30 km radius from the selected one (sorted in a

ascending inter-site distance order)© Forsk 2009 Slide 92 of 149Confidential – Do not share without prior permission

Exporting Neighbour Relationships

Possibility to copy/paste or to export the list of neighbours


Training Program

1. LTE Concepts



4. LTE Predictions

5. MIMO Modelling









Automatic resource planning overview

Automatic physical cell ID allocation process

Automatic frequency allocation process

Frequency allocation examples


Automatic Resource Planning Overview

Automatic Physical Cell ID PlanningBased on neighbour and distance relations

Allocation of S-SCH IDs and P-SCH IDs

Automatic Resource Planning (Optional)Based on interference matrices, neighbour, distance relations

Possibility to lock frequencies for cells

Can work with more than one frequency band in the same document

Can also allocate physical cell IDs taking interference matrices into account


Automatic Physical Cell ID Allocation Process

Physical Cell ID definition : (physical cell ID of the cell)Physical cell IDs defined in the 3GPP specifications.

Integer value from 0 to 503• 504 unique physical-layer cell identities.• Grouped in 168 unique cell ID groups (called S-SCH IDs in Atoll), each group containing 3 unique

identities (called P-SCH IDs in Atoll)• S-SCH ID belongs to [0,167] and P-SCH ID is either 0, 1 or 2.• Each cell’s reference signals transmit a pseudo-random sequence corresponding to the physical cell

ID of the cell.

Physical Cell ID allocation to cellsGoals

• Avoid using the same pseudo-random sequence in nearby cells• Can cause problems in cell search and selection

• Avoid using the same P-SCH ID to nearby cells• Can cause a lot of interference

• Use preferably the same S-SCH ID to cells of the same site• Can help in measurements and handover procedures



Automatic Physical Cell ID allocation in AtollBased on an iterative cost-based algorithm

Different physical Cell ID allocation plans are tried and a cost calculated for each

The best physical Cell ID allocation plan is the one with the lowest cost

The cost is calculated for cells with the following relations• Neighbours (optional)• Distance between cells < min reuse distance (optional)• Frequency plan

Relations between cells can have different importance in the final cost• The importance of neighbour relation is calculated during the automatic neighbour allocation • The importance of the relation based on the distance between cells (weighted by the antenna

azimuths)



Automatic physical Cell ID allocation prerequisitesFrequency plan

• A channel manually assigned to each cell

Neighbour plan• Manually or automatically obtained• Importance values



Automatic physical Cell ID allocation process

Commit Physical Cell Ids to cells

S-SCH ID allocation strategy

Allocation cost constraints

Allocated Physical Cell Ids, P-SCH IDs and S-SCH IDs


Automatic Frequency Allocation Process

Optimization of the frequency allocation in a network

The optimum frequency plan minimizes the interference in the network

Compliance with given constraintsExcluded channels

Interferences

Reuse distance

Neighbour relations

…

The algorithm starts with the current frequency plan as the initial state

Frequencies can be locked for cells

The AFP can work with more than one frequency band in the same document

Channels can be excluded



Based on an iterative cost-based algorithm

Different frequency allocation plans are tried and a cost calculated for each

The best frequency allocation plan is the one with the lowest global cost

The cost is calculated for cells thanks toInterference matrices

• Probabilities of interference in co- and adjacent channel cases• A probability calculated for each case for each interfered-interfering cell pair

Distance relation• For distance between cells < min reuse distance• Takes into account distance, orientation of cells

Neighbours• Takes into account importance of neighbour relation (adjacent, co-site)



Automatic resource allocation process

Commit channels to cells

Interference matrices calculation (to run before frequency

allocation)

Allocated channels

Possibility to allocate Physical Cell IDs or

frequencies

Allocation constraints



Interference matrix calculationFor each cell pair, interference probability for co and adjacent channel cases

Interference probability is the ratio between• Interfered surface area within the best server coverage area of the studied cell• Best server coverage area of the studied cell


Frequency Allocation Examples

Automatic frequency allocation in Atoll (example)Same channel all over

Reference Signal C/(I+N) Level (DL) (dB) >=30 0.0048Reference Signal C/(I+N) Level (DL) (dB) >=25 0.084Reference Signal C/(I+N) Level (DL) (dB) >=20 1.1228Reference Signal C/(I+N) Level (DL) (dB) >=15 5.8348Reference Signal C/(I+N) Level (DL) (dB) >=10 17.4132Reference Signal C/(I+N) Level (DL) (dB) >=5 40.244Reference Signal C/(I+N) Level (DL) (dB) >=0 77.7116Reference Signal C/(I+N) Level (DL) (dB) >=-5 134.9424Reference Signal C/(I+N) Level (DL) (dB) >=-10 160.302Reference Signal C/(I+N) Level (DL) (dB) >=-15 161.0816Reference Signal C/(I+N) Level (DL) (dB) >=-20 161.0816


Automatic frequency allocation in Atoll (example)Manual allocation with 3 channels




Automatic frequency allocation in Atoll (example)Automatic allocation with 3 channels




Automatic frequency allocation in Atoll (example)Manual allocation with 6 channels




Automatic frequency allocation in Atoll (example)Automatic allocation with 6 channels




Training Program

1. LTE Concepts



4. LTE Predictions

5. MIMO Modelling









Channel and Physical Cell ID search tools

Physical Cell ID allocation audit

Physical Cell ID histograms


Search Tool Overview

Tool to visualise channel and P-SCH ID reuse on the map

Possibility to find cells which are assigned a given :• Frequency band + channel• Physical Cell ID • P-SCH ID• S-SCH ID

Way to use this tool

Create and calculate a coverage by transmitter with a colour display by transmitter

Open the search tool available in the view menu


Channel Search Tool

Channel reuse on the map

Colours given to transmitters• Red : co-channel transmitters

• Yellow : multi-adjacent channel (-1 and +1) transmitters

• Green : adjacent channel (-1) transmitters• Blue : adjacent channel (+1) transmitters

• Grey : other transmitters

Frequency band and Channel number


Physical Cell ID Search Tool

Physical Cell ID, P-SCH ID and S-SCH ID reuse on the map

Colours given to transmitters• Red or grey: if the transmitters carries or not the specified resource value (Physical Cell ID,

P-SCH ID or S-SCH ID)

Resource type Resource value


Physical Cell ID Allocation Audit

Verification of the allocation inconsistenciesRespect of the reuse distance

Respect of neighbourhood constraints

If the Physical Cell ID allocation strategy is respected

Inconsistencies are displayed in the default text editor


Physical Cell ID Histograms

View of the Physical Cell ID distribution

Dynamic pointer


Training Program

1. LTE Concepts



4. LTE Predictions

5. MIMO Modelling









Simulation process

Simulation creation

Scheduling in simulations

Simulation results

Analysis of simulations


Simulation Process

What’s a simulation in Atoll?

Distribution of users at a given moment (= snapshot)

Based on subscriber lists

Suitable for a fixed wireless access application

Based on traffic maps

Similar to UMTS/CDMA/WiMAX simulation process

Can be used for a fixed application (statistical user-list modelling)

Can be used for a mobile application (Monte-Carlo distribution of mobile users)


Simulation Process

Requirement: subscriber list and/or traffic map(s)

The user distribution is generated using a Monte-Carlo algorithm

Based on traffic database and subscriber list/traffic map(s)

Weighted by a Poisson distribution

Each user is assigned

A service, a mobility type, a terminal and an activity status by random trial• According to a probability law using traffic database

A geographic position in the traffic zone by random trial• According to the clutter weighting and indoor ratio (user location is the same as subscriber location if

the simulation is based on a subscriber list)


Simulation Creation

Number of simulations to run for the current

session

Optional growing factor on the selected traffic map(s)

Selection of traffic map(s) as traffic input

Selection of subscriber list(s) as traffic input (dedicated to fixed wireless access application)

Load constraints to respect during simulations (global

value or value per cell)


Scheduling in Simulations

Scheduling and radio resource managementFiltering of mobiles up to cell capacity limits (max UL and DL loads)

Different schedulers available:• Max C/I• Proportional Demand• Proportional Fair

First pass• Resource allocation for the minimum throughput demands depending on the service priorities of the

users (priority field in services)

Second pass• Distribution of the remaining resources between users according to the schedulers defined in each cell

in order to reach the max throughput demand


Simulation Results (1)

Analysis provided over the focus zone

Main simulation results includePer cell

• UL and DL traffic loads• UL noise rise• UL and DL aggregate cell throughputs• Traffic input and connection statistics• …

Per mobile• Serving transmitter and cell• Azimuth and tilt (towards the serving cell)• Reference signal, SCH/PBCH, PDSCH, and PUSCH signal levels• Reference signal, SCH/PBCH, PDSCH, and PUSCH CINR and interference levels• Best bearers based on PDSCH and PUSCH CINR levels• Cell throughputs, cell capacities, and user throughputs PDSCH and PUSCH CINR levels• Connection status and rejection cause• …



Analysis provided over the focus zone

5 tabs : statistics, sites, cells, mobiles, initial conditions



Writes the UL/DL traffic loads and the UL noise rise into the

cells table



Display the users (terminals) on the map depending on the connection

status


Analysis of Simulations

Calculation of LTE prediction studies based on simulations

Analysis of a single simulation

Average analysis of all the simulations in a group

Prediction based on the results of the simulation (DL load, UL noise rise, etc)

Prediction based on the average of simulations in the group (average DL load,

and average UL noise rise)


Training Program

1. LTE Concepts



4. LTE Predictions

5. MIMO Modelling









Import of test mobile data path

Drive test management

Drive test graphic analysis


Import of Test Mobile Data Paths

OverviewMeasurement path related to a serving cell and its neighbours

Check and improve the network quality

ImportSupported files

• Any ASCII text file (with tab, semi-colon or blank character as separator)• TEMS FICS-planet export (*.Pln)• TEMS text export (*.Fmt)

Procedure• Standard import as in excel• Mandatory information

• Position of measurement points• Physical Cell ID

• You can import any additional information related to measurement points• Definition and storage of import configurations• Multiple import


Drive Tests Managements

TableList of all the measurement points with their attributes and additional information

Standard content management and tools (filters, copy-paste, etc...)



Management of measurement path points

Option of extracting a field related to a specific transmitter along a path

Option of creating as many CW measurement paths as the number of involved transmitters along the path. These data can be used to calibrate any propagation model

Creation of any prediction on the transmitters measured

along the path




Filter per

type(s) of

clutter

Advanced filter on additional survey data

Permanent deletion of out-of-filter points




Option of preparing additional prediction studies along the path using the existing

transmitter parameters (antennas, propagation models, etc…)

List of defined studies in the measurement

table




Using the Atoll display dialog, you can display the points according to any data

contained in the measurement table


Drive Tests Graphic Analysis

Test mobile data analysis window

Display on the map

Transmitters measured and indexed for the current point.


Drive Tests Graphic Analysis

Test mobile data analysis window

Synchronisation table – map – measurement

window

Option of displaying variation of any

selected numeric field along the selected

path


Training Program

1. LTE Concepts



4. LTE Predictions

5. MIMO Modelling








Terminologies and Concepts in Atoll

ResourcesIn Atoll, the term "resource" is used to refer to the average number of resource units, expressed in % (as traffic loads, when the average is performed over a considerably long duration) of the total number of resource units in a superframe of 1 sec.

FrameAn LTE frame is 10 ms long. The duration of a frame is a system-level constant. Each frame comprises 10 1 ms-long subframes, with each subframe containing 2 0.5 ms-long slots. Each slot can have 7 or 6 symbol durations for normal or extended cyclic prefix, respectively, and for a 15 kHz subcarrier width. A slot can have 3 symbol durations for extended cyclic prefix used with a 7.5 kHz subcarrier width. LTE includes specific frame structures for FDD and TDD systems. For TDD systems, two switching point periodicities can be used; half-frame or full frame. Half-frame periodicity provides the same half-frame structure as a TD-SCDMA subframe. The PBCH and the two SCH are carried by subframes 0 and 5, which means that these 2 subframes are always used in downlink. A subframe is synonymous with TTI (transmission time interval), i.e., the minimum unit of resource allocation in the time domain.



LTE frame structures (DL: blue, UL: orange, DL or UL: green)



Resource Element, Symbol, or Modulation SymbolIn Atoll a symbol refers to one resource element or one modulation symbol, which is 1 symbol duration long and 1 subcarrier width wide.

Symbol DurationIn Atoll a symbol duration refers to one OFDM symbol, which is the duration of one modulation symbol over all the subcarriers/frequency blocks being used.

SubcarrierAn OFDM channel comprises many narrowband carriers called subcarriers. OFDM subcarriers are orthogonal frequency-domain waveforms generated using Fast Fourier Transforms.

Frequency BlockIt is the minimum unit of resource allocation in the frequency domain, i.e., the width of a resource block, 180 kHz. It is a system-level constant. A frequency block can either contain 12 subcarriers of 15 kHz each or 24 subcarriers of 7.5 kHz each.



Resource BlockIt is the minimum unit of resource allocation, i.e., 1 frequency block by 1 slot. Schedulers are able perform resource allocation every subframe (TTI, transmission time interval), however, the granularity of resource allocation 1 slot in time, i.e., the duration of a resource block, and 1 frequency block in frequency.

LTE resource blocks



LTE Logical Channels: LTE logical channels include:Broadcast Control Channel (BCCH) (DL): Carries broadcast control information.

Paging Control Channel (PCCH) (DL): Carries paging control information.

Common Control Channel (CCCH) (DL and UL): Carries common control information.

Dedicated Control Channel (DCCH) (DL and UL): Carries control information dedicated to users.

Dedicated Traffic Channel (DTCH) (DL and UL): Carries user traffic data.

Multicast Control Channel (MCCH) (DL): Carries multicast control information.

Multicast Traffic Channel (MTCH) (DL): Carries multicast traffic data.

LTE Transport Channels: LTE transport channels include:Broadcast Channel (BCH) (DL): Carries broadcast information.

Paging Channel (PCH) (DL): Carries paging information.

Downlink Shared Channel (DL-SCH) (DL): Carries common and dedicated control information and user traffic data. It can also be used to carry broadcast and multicast control information and traffic in addition to the BCH and MCH.

Uplink Shared Channel (UL-SCH) (UL): Carries common and dedicated control information and user traffic data.

Multicast Channel (MCH) (DL): Carries multicast information.

Random Access Channel (RACH) (UL): Carries random access requests from users.



LTE Physical Layer Channels: LTE physical layer channels include:Physical Broadcast Channel (PBCH) (DL): Carries broadcast information.

Physical Downlink Shared Channel (PDSCH) (DL): Carries paging information, common and dedicated control information, and user traffic data. It can also be used to carry broadcast and multicast control information and traffic in addition to the PBCH and PMCH. Parts of this channel carry the primary and secondary synchronisation channels (P-SCH and S-SCH), the downlink reference signals, the physical downlink control channel (PDCCH), the physical HARQ indicator channel (PHICH), and the physical control format indicator channel (PCFICH).

Physical Uplink Shared Channel (PUSCH) (UL): Carries common and dedicated control information and user traffic data.

Physical Uplink Control Channel (PUCCH) (UL): Carries control information.

Physical Multicast Channel (PMCH) (DL): Carries multicast information.

Physical Random Access Channel (PRACH) (UL): Carries random access requests from users.



LTE logical, transport, and physical layer channels (DL: blue, UL: orange, DL or UL: green)



UserA general term that can also designate a subscriber, mobile, and receiver.

SubscriberUsers with fixed geographical coordinates.

MobileUsers generated and distributed during simulations. These users have, among other parameters, defined services, terminal types, and mobility types assigned for the duration of the simulations.

ReceiverA probe mobile, with the minimum required parameters needed for the calculation of path loss, used for propagation loss and raster coverage predictions.

BearerA Modulation and Coding Scheme (MCS) used to carry data over the channel.



Peak RLC ThroughputThe maximum RLC layer throughput (user or channel) that can be achieved at a given location using the highest LTE bearer available. This throughput is the raw data rate without considering the effects of retransmission due to errors and higher layer coding and encryption.

Effective RLC ThroughputThe net RLC layer throughput (user or channel) that can be achieved at a given location using the highest LTE bearer available computed taking into account the reduction of throughput due to retransmission due to errors.

Application ThroughputThe application layer throughput (user or channel) that can be achieved at a given location using the highest LTE bearer available computed taking into account the reduction of throughput due to PDU/SDU header information, padding, encryption, coding, and other types of overhead.

Channel ThroughputsPeak RLC, effective RLC or application throughputs achieved at a given location using the highest LTE bearer available with the entire cell resources (downlink or uplink).



User ThroughputsPeak RLC, effective RLC or application throughputs achieved at a given location using the highest LTE bearer available with the amount of resources allocated to a user by the scheduler.

Traffic LoadsThe uplink and downlink traffic loads are the percentages of the uplink and the downlink frames in use (allocated) to the traffic (mobiles) in the uplink and in the downlink, respectively.

Uplink Noise RiseUplink noise rise is a measure of uplink interference with respect to the uplink noise. This parameter is one of the two methods in which uplink interference can be expressed with respect to the noise. The other parameter often used instead of the uplink noise rise is the uplink load factor. Usually, the uplink load factor is kept as a linear value (in %) while the uplink noise rise is expressed in dB. The two parameters express exactly the same information, and can be inter-converted.


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A-LTE

Documents

multicast

carries multicast

carries paging

dedicated

atollsupports

uplink load

ul noise rise

frequency