system-level modelling: is-wireless tutorial on ieee globecom 2015

System-level modelling of HetNets, Carrier Aggregation and Scheduling

in MATLAB Dr. Sławomir Pietrzyk

IEEE Globecom 2015 industry tutorial

Tutorial Outline

• About us

• LTE/LTE-Advanced introduction

• E-UTRA Rel.10: HetNets, Carrier Aggregation and SON

• LTE MAC Lab – system level simulator in MATLAB

• LTE-A HeNet use cases modelled in MATLAB – Heterogeneous Network

– Carrier Aggregation

– Scheduling

ABOUT

IS-Wireless is an advanced wireless communications company. We are developing protocols, simulators and IP algorithms.

We also deliver 4G and 5G courses.

Company overview

• IS-Wireless is a Polish software developer and IP provider specializing in advanced solutions for wireless systems.

• IS-Wireless develops 4G and 5G algorithms, protocols and tools that are targeted primarily at early technology adopters including ODMs, OEMs, chip vendors and operators.

Founder and CEO

Ownership

Location

Industry

Products

Services

Web

COMPANY FACTS

Slawomir Pietrzyk

Privately held

Piaseczno near Warsaw, Poland, EU

Wireless communications

Software: protocols and simulators, IP: algorithms and know-how

Technical courses, wireless systems design

www.is-wireless.com

LTE-Advanced

Introduction

4G System Requirements

IMT Advanced

…a set of key features for

ITU-R

Has defined…

…which are as follows:

• a high degree of commonality and functionality worldwide while retaining the flexibility to support a wide range of services and applications in

a cost efficient manner;

• compatibility of services within IMT and with fixed networks;

• capability of interworking with other radio access systems;

• high quality mobile services;

• user equipment suitable for worldwide use;

• user-friendly applications, services and equipment;

• worldwide roaming capability;

• enhanced peak data rates to support advanced services and applications (100Mbit/s for high and 1Gbit/s for low mobility were established

as targets for research).

…for the technology, that can be called:

A 4G System

3GPP Features’ Roadmap

2008 2009 2010 2011 2012 2013 2014 2015 2016

Release 8: • MIMO (4 layers) • TF Scheduling • FDD/TDD mode • OFDMA/SCFDMA • HARQ • Reduced

architecture • Adaptive MCS

Release 9: • MBMS based on SFN • SON • Location services

Release 10: • Carrier Aggregation • MIMO (8 layers in DL, 4

layers in UL) • Relay nodes • Enhanced HeNB and

HetNets • eICIC

Release 11: • CoMP • FeICIC • ePDCCH

Release 12: • Device-to-Device • Proximity Services • Higher modulation order

(256 QAM) • Dual connectivity • SON enhancements • Mobility enhacements

Release 13: • LTE in unlicensed

spectrum • Carrier Aggregation

enhancement • Enhancements for D2D • Full-dimension MIMO

LTE-Advanced Introduction LTE Rel. 8/9 Basic Radio Access Techniques Summary

OFDMA SC-FDMA

• OFDMA Scheme

• Adaptive modulation: QPSK, 16QAM, 64QAM

• MIMO (2x2, 4x4, SISO, TxDiversity, SU-MIMO)

• System BW: 1.4, 3, 5, 10, 15, 20 MHz

• HARQ and QoS support

DL Radio Interface Features

• SCFDMA Scheme

• Adaptive modulation: QPSK, 16QAM, 64QAM (opt)

• System BW: 1.4, 3, 5, 10, 15, 20 MHz

• HARQ and QoS support

UL Radio Interface Features

E-UTRA Rel. 8/9 Downlink E-UTRA Rel. 8/9 Uplink

SC-FDMA OFDMA

eNB

eNB

LTE-Advanced Introduction LTE Rel. 10 Radio Access Enhancements Summary

SC-FDMA

• Carrier Aggregation

• MIMO for up to 8x8 (MU-MIMO and BF)

• Additional Pilots (CSI and UE specific)

DL Radio Interface Additional Features

• Carrier Aggregation

• MIMO for up to 4x4 (SU-MIMO, MU-MIMO)

• Clustered SCFDMA Scheme

UL Radio Interface Additional Features

E-UTRA Rel. 10 Downlink E-UTRA Rel. 10 Uplink

OFDMA

eNB

eNB

RN

Relaying

RN

Relaying


SC-FDMA

• Coordinated Multipoint

• Interference rejection combining (IRC) UE

receiver

DL Radio Interface Additional Features

• Coordinated Multipoint using Virtual Cell ID (VCID)

UL Radio Interface Additional Features

E-UTRA Rel. 11 Downlink E-UTRA Rel. 11 Uplink

OFDMA

eNB

eNB RRH

small cell

CoMP using VCID

CoMP


• Aggregating more CCs

• More layers in MIMO

• Device discovery

Radio Interface Additional Features

E-UTRA Rel. 12

eNB

eNB small cell

256 QAM

Discovery

E-UTRA Rel. 12


• 3D antennas (full-dimension beamforming)

• LTE in unlicensed

Radio Interface Additional Features

E-UTRA Rel. 13

eNB

Unlicensed band

E-UTRA Release 10

Heterogeneous Networks (HetNets)

E-UTRA Rel. 10 HetNets Heterogeneous Network Concept and Cell Types

Internet

Homogeneous Network

EPC • Regular network

• General macro-cell

approach

• Equal power nodes

• Large coverage

• Planned sites

Heterogeneous Network

HeNB

RN

EPC

eNB

MeNB Macro

PeNB PeNB

Pico

• Non regular network

• Overlapping cells

• Different node types

• Different power levels

• Different coverages

• HeNBs - not planned

sites (interference

problem)

Extended macrocell Max Tx Power = 30dBm

Macrocell Max Tx power = up to regulator

Picocell

(eNB with lower power in hot zones –

for capacity increase) Max Tx power = 24dBm

Femtocell

(CSG approach) Max Tx power = 20dBm

Backhaul links

eNB

eNB

eNB

E-UTRA Rel. 10 HetNets LTE ICIC and SON – HeNB Configuration Example (Over the Air)

HeNB

MeNB

1. Plug in to power supply and internet

2. Configuration downloading

3. Carrier sensing and measurements

4. Self configuration: Power and time/frequency settings

5. Adaptive cell adjustments by PC and FFR: more users in hotspot – higher power less users – less power

f1

f1

Time domain shift

Time and frequency domain shift

10MHz

(MeNB)

10MHz

(HeNB)

1SF

10MHz

(MeNB)

5MHz

(HeNB)

10MHz

(MeNB)

MeNB

DL Radio frame

MeNB

DL Radio frame

HeNB

DL Radio frame

HeNB

DL Radio frame

PDSCH PDCCH

PBCH & SS

3 symbols time shift

for CR

1 Subframe timing change

for sync and PBCH

3 symbols time shift

for CR

Fc shift

(provides sync and PBCH shift)

E-UTRA Rel. 10 HetNets HeNB RF Issues

HeNB

HeNB

MeNB

DL Receiver ”HeNB Sniffer”

”NW listening module”

Macro eNB Measurements RSRP, RSRQ, Cell ID, Frame Timing

HUE to MeNB pathloss calc.

other HeNB Measurements RSRP, Cell ID

HUE to HeNB pathloss calc

Max overall Tx power, Pmax = 20dBm

1 Tx

20dBm / AP 2 Tx

17dBm / AP 4 Tx

14dBm / AP 8 Tx

11dBm / AP

E-UTRA Rel. 10 HetNets LTE ICIC – Picocell ICIC Mechanisms

Non-Carrier Aggregation Scenarios

Carrier Aggregation Scenario

MeNB

PeNB

X2

Over X2 transmission

agreement: subframe reservation

Almost Blank Subframes usage (time domain resource partitioning

max power in non-overlapping subframes)

Pico cell range extension method (less than max power in some subframes)

MeNB DL Tx

PeNB DL Tx

subframes

subframes

MeNB DL Tx

PeNB DL Tx

subframes

subframes

MeNB and PeNB

are transmitting with

max powers

(in different SFs)

PeNB transmits in all SFs

MeNB transmits with lower

power in certain SFs

MeNB

PeNB

f CC1

(PCC)

CC2

(SCC)

f CC1

(SCC)

CC2

(PCC)

CC1

CC2

t

t

t

t

PDCCH

PDSCH

Scheduling

assignment

MeNB PeNB

Use of Cross-Carrier

scheduling

For CEU use PCell

For CCU use SCell

MeNB’s power is lower in this SF

(SNIR at PeNB higher)

PHY Enhancements

Carrier Aggregation (Bandwidth Extension)

E-UTRA Rel. 10 PHY Bandwidth Extension by Carrier Aggregation (Component Carriers)

Example CA Configurations

f

BW

(1.4 MHz – 20MHz)

f

BW

(1.4 MHz – 20MHz)

Rel.8 Bandwidth – max 20MHz

Component Carrier

(Rel. 8 Carrier)

Rel.10 Bandwidth – max 100MHz

(up to 5 Component Carriers)

LTE Rel. 8 Carrier LTE Rel. 10 Carrier Aggregation

f

20MHz 20MHz

40MHz

f

20MHz 20MHz

100MHz

20MHz 20MHz 20MHz

f

20MHz 10MHz

35MHz

5MHz

Equal size CCs

Various sizes CCs

E-UTRA Rel. 10 PHY Carrier Aggregation Options

Intraband Contiguous CA • Less likely scenario for today allocations (no 100MHz bands)

• Possibly to be used in 3.5GHz bands

• Considered for DL and UL

Intraband Non-Contiguous CA • E.g. scenario where operator has two non contiguous carriers with other operator’s allocation inbetween

• Considered for DL and UL

Interband Non-Contiguous CA

• Multiple CCs belongs to different bands (e.g. 2.6GHz and 800MHz are aggregated)

• Can improve mobility robustness by exploiting different radio propagation characteristics of different bands

• Require additional complexity in RF front end

• Considered for DL only

f

CC1

Band A (e.g. 1800 MHz)

e.g. 20MHz CC x 5

f

CC1


e.g. 20MHz CC x 3

f

CC1


e.g. 20MHz CC x 2

CC2

Band B (e.g. 2600 MHz)

CC2 CC3

CC2 CC3 CC4 CC5

It is easiest to use contiguous CA:

•Single IFFT

•Easier scheduling

•Single RF units possible

E-UTRA Rel. 10 PHY Carrier Aggregation for FDD and TDD

Example FDD Configurations

No

aggregation

Symmetric

aggregation

f

DL UL

f

DL UL

Asymmetric

aggregation f

DL UL

Example TDD Configurations

f

DL/UL

f

DL/UL

Asymmetric

aggregation not

possible!

E-UTRA Rel. 10 PHY DL and UL Radio Frames Consideration for Rel. 8 and Rel. 10

Downlink Radio Frames Rel. 8 DL Radio Frame (Single DL Carrier)

Rel. 10 DL Radio Frames (CA with 3 CCs)

BW (e.g. 20MHz)

10ms

CC1 CC2 CC3

PDCCH per CC

(backhwards compatibilty for rel. 8 UEs)

Broadcast per CC

Uplink Radio Frames Rel. 8 UL Radio Frame (Single UL Carrier)

Rel. 10 UL Radio Frames (CA with 3 CCs)

PUCCH per CC

(backwards compatibility for rel.8 UEs)

PUSCH

PUCCH

10ms

LTE and SON Introduction

SON Introduction

SON Introduction SON Concept – Drivers for SON

Technical Drivers

Business Drivers Increasing demand for diversity of services

Need to reduce Time-To-Market for innovative / new services

High performance required • Growing number of BW hungry services • Growing number of devices and change of device character (M2M)

Heterogeneous Network to be cooperatively managed • Macro/Micro/Pico/Femto cells and Relays

Overlaying multiple networks for a single operator • 2G/3G/LTE/WiFi

Higher operational frequencies • Increase number of cells required / higher NW cost

Increasing complexity of networks • Multitude / growing number of parameters with interdependencies • Multitude of RRM algorithms working at different time scales

HO thresh PRB conf

TimeToTrig

Hysteresis

AC thresh

AC

PSched

LTE

GSM UMTS

WiFi Core

cdma 2000

SON Introduction SON Concept – Expected SON Benefits

OPEX Reduction

Reduction of Drive Tests (UE & eNB meas)

Reduction of manual effort in planning (by param settings)

Energy saving (energy efficiency)

Less staff for OAM

Less / no site visits

Simplified deployment of femto cells

Less leased transmission lines required due to optimized resource utilization

Reduction of manual effort for monitoring & optimization (e.g. identify of problems/troubleshooting)

SON

Tech

nical

Be

ne

fits B

usin

ess

Be

ne

fits

More Capacity Better Coverage Improved Quality Increased Automation

Streamlined CAPEX Improved ROI Reduced Churn Lower OPEX

Capex Reduction

Postponed investments (delayed capacity expansions)

Less sites for the same cap/cov targets (reducing amount of equip.)

Churn Reduction / Improved ROI

Better service quality (optimized NW)

Better service availability

Fast recovery from failures (reduction of NW „downtime”

Less human errors

Faster Time to Market

Reduction of time for first commercial operation

Fast new eNB config and run

SON Introduction SON Concept – Evolution Path Towards Autonomous System

OAM

1. Basic

Meas

Action

2. Managed

Meas

Action

OAM

3. Predictive

Auto Algs

Suggested

change

Approved

OAM

4. Adaptive

Auto Algs

Suggested

change

Approved

Policy

Long term

performance report

Adjust policy

OAM

5. Autonomic

Auto Algs

Suggested

change

Approved

Policy

Adjust policy

One time high level

policy definition

All NEs are managed independetly

Collect & aggregate info from NEs into few consoles where required configs are

initiated manually

Automatic algs (e.g. SON) recommend actions based on gathered info. Actions need to be

approved

System automatically takes action based on measurements controlled by low level policies set/adjusted by operator

Fully integrated system is dynamically managed based on business rules and policies

SON Introduction NW Management: No-SON vs SON Approaches

NO SON SON Manual Configuration Self-Configuration

Manual Optimization Self-Optimization

Manual Fault Management Self-Healing

eNB

Manual setup (on-site visits)

eNB

Plug in

OAM

Plug&Play (automatic config)

eNB

Config

download

eNB

Poor quality

Performance Indicators

Hmm… how to adjust?

AGES later… adjust params

eNB

eNB

Better quality

eNB

eNB

Poor quality

eNB

eNB

Performance Indicators

Few seconds later… adjust params

Best/optimum quality

eNB

eNB

eNB Failure Alarm

OAM

AGES later… recovery team (on site visit)

eNB

eNB

eNB Failure

Alarm

OAM

Alarm

Few seconds later… reload/fallback software

Take over

UEs

OAM

Auto-Tune

Auto-Repair

SON Introduction SON Background – Involved Parties

• NGMN (www.ngmn.org) – Wireless operator consortium provides requirements on next generation networks

– Identifies real needs from operators about what is necessary for OAM to optimize

– Defines recommendations on SON & OAM Requirements

• 3GPP (www.3gpp.org) – Standardization body for 2G/3G/LTE/LTE-Advanced

– Defines a framework based on NGMN inputs to enable SON

– Defines interfaces / messages / procedures to enable SON

– Defines Use Cases for SON features

– Defines common language (XML) and network management architecture (NMS)

– Does not define algorithms

• SOCRATES (www.fp7-socrates.org) – Self-Optimisation and self-ConfiguRATion in wirelEss networkS

– FP7 project to provide SON features (individual algorithms) – Jan 2008 to Dec 2010

– Worked closely with NGMN to get real needs from operators

– Worked closely with 3GPP to define the algorithms within a framework

– Developed algorithms for Self-Configuration, Self-Optimization, Self-Healing, X-Map Estimation

– Provided requirements and framework for SON Coordination

LTE-Advanced

Deployment Issues

LTE-Advanced Deployment RAN Performance Enhancements Due to LTE-Advanced Components

eNB

RN

UE position [m]

Data

Rate

Cell Edge User

(CEU) Cell Center User

(CCU)

LTE Rel. 8

Coverage hole

LTE-Advanced Rel. 10/11

Relays and

Beamforming

Higher order

MIMO

Carrier

Aggregation

CoMP

CoMP

Simple formula

Max_throughput = Required_Spectral_Efficiency * BW

Assuming

MIMO 8x8 and BW 100MHz

We end up at

Max_thr = 30bit/s/Hz * 100MHz = 3Gbit/s

LTE-Advanced Deployment Backward Compatibility to LTE Rel. 8

Bandwidth Issues

f

Total BW

e.g. 100MHz

Component Carrier

(20MHz)

UE capabilities

100MHz support

40MHz support

20MHz support

Rel. 10 UE

Rel. 10 UE Rel. 10 UE

Rel. 8 UE Rel. 8 UE Rel. 10 UE Rel. 10 UE Rel. 8 UE

UEs during NW attach signalls the supported release and number of supported Carriers

CA concept allows to be backward compatible to Rel. 8 (separate PHY per CC)

Other backward compatibility Issues

Issue Backwards compatibility support

PHY signalling PDCCH and PUCCH per Component carrier

RF Processing per component carrier

UE Rel. 8 categories Signalled explicitely

MIMO Support Signalled explicitely

Relay transparency Use of MBSFN subframe

Scheduling Per component carrier

LTE-Advanced Deployment Migration from LTE Rel. 8 to LTE-Advanced Rel. 10 (example)

Rel. 8 Macrocell Deployment

R.8 eNB R.8 eNB

f

f

R.8 eNB R.8 eNB

f

Mo

re B

W a

nd

MIM

O

(soft

ware

upgra

de)

R.10 eNB

R.8 eNB R.8 eNB

HetN

et

MIMO 2x2

BW 20MHz

MIMO 4x4

BW 40MHz

RN

HeNB

R.10 eNB

RN

HeNB

Mo

re B

W a

nd

MIM

O

f

R.10 eNB R.10 eNB

MIMO 4x4

BW 40MHz

MIMO 8x8

BW 100MHz

Rel. 10 HeNBs and Relay Nodes Deployment

R.10 eNB

Additional Component Carrier Aggregations and MIMO extensions

Rel. 10 Macrocell Deployment (base case for CA and MIMO)

E-UTRA Rel. 10 Carrier Aggregation Deployment Scenarios for CA

Scenario 1 (supported for DL and UL in Rel. 10)

• F1 and F2 cells - co-located and overlaid (nearly the same coverage). • Both freqs provide sufficient coverage. • Mobility – based on F1 or F2 coverage • F1 and F2 in the same band, e.g., 2.6 GHz

Description Example

F1

F2

• F1 and F2 cells - co-located and overlaid (F2 - smaller coverage due to larger path loss) • F1 provides sufficient coverage, F2 - used to improve throughput. • Mobility - based on F1 coverage. • F1 and F2 in different bands, e.g., F1 = 800 MHz, F2 = 3.5 GHz.

• F1 and F2 cells - co-located. F2 antennas directed to F1 cell edges (cell edge thrpt increased) • F1 provides sufficient coverage, F2 can have holes, e.g., due to larger path loss. • Mobility - based on F1 coverage. • Likely when F1 and F2 in different bands, e.g., F1 = 800 MHz, F2 = 3.5 GHz.

• F1 provides macro coverage, on F2 (RRHs) are used to improve throughput at hot spots. • Mobility - based on F1 coverage. • Likely when F1 and F2 in different bands, e.g., F1 = 800 MHz, F2 = 3.5 GHz.

• Similar to scenario #2, but frequency selective repeaters are deployed - coverage is extended for one of the carrier frequencies.



Scenario 4 (supported for DL in Rel. 10)

Scenario 5 (supported for DL in Rel. 10)

LTE-Advanced

HetNet Deployment Issues

LTE-Advanced Deployment Femto-cell (HeNB) Typical Attributes

Attribute name Macro eNB HeNB

Infrastructure finance Operator End User

Backhaul Fiber/Microwave Existing broadband internet

Planning Operator End user (no central planning)

Deployment Operator rollout End user one touch installation (SON based)

QoS Operator controlled Best effort

Control Operator via O&M Operator via Internet

Mobility Typical scenario (outdoors and moving)

Nomadic / best effort HO (indoors and sitting down)

Rep

HeNB

eNB

RN

L1 Repeater (amplifies the signal – backward

compatible to Rel. 8 UEs)

L3 Rel. 10 Relay Node •uses MBSFN subframe for backhauling known by

Rel. 8 UEs

•it is backward compatible and can be used for relaying

to Rel. 8 terminals

•Transparent to Rel. 8 and Rel. 10 terminals

f CC1

(PCC)

CC2

(SCC)

f CC1

(SCC)

CC2

(PCC)

Carrier aggregation for Hetnet Cross carrier scheduling for

interference avoidance for signalling

Relaying

HeNBs

Femtocells deployment in a building •No planning sites

•Switched on and off depending on end user decision

Femtocell

location

Walls

Interference

(ICIC required)

LTE-Advanced Deployment HetNet Deployment Issues

Self-Optimization for HetNets Resource Partitioning for Femto-Scenario (Example)

Scenario and algorithm (graph based scheme)

Example graph coloring for

resource distribution

A

B C

Interference

Feedback

Central Controller (HeMS)

A

B C

Femto

cell

Interference

Interferer: A

A,C

B

Interfering neighbor discovery • UE makes measurements • HeNB identifies its interfering neighbors according to

a predefined SINR thresh

1

HeNBs send CellIDs of the interfering neighbors to central node

2 Central controller maps info to interference graph • HeNB – node • Interference relation between two HeNBs - edge

3

Identify the bandwidth distribution (PRB-HeNB) pairs which maximizes the resource efficiency

A

C

E

B D

Freq

Power

Basic / not optimized case

Resource efficiency:

5/15

Available resources

A

C

E

B D


9/15

A

C

E

B D


6/15

LTE MAC Lab

Product presentation

LTE MAC Lab Overview

LTE MAC Lab is an Advanced HetNets system-level simulation tool running under MATLAB environment. It allows user to model a wireless LTE network deployment, analyze its performance and understand dynamic mechanisms of the radio interface.

Main Applications

LTE MAC Lab is an universal tool for LTE MAC simulation. Software can be used by ODM, OEM, Chip manufacturers, Protocol Stack Developers, Operators, Research Institutes, Univerisities, Training Companies. Main Applications: • MAC prototyping, where LTE MAC Lab shortens the development time.

• R&D, where LTE MAC Lab provides simulation framework.

• Development of MAC protocols and RF processing, where LTE MAC Lab

serves as a reference model.

• Network modeling and analysis, where LTE MAC Lab allows to estimate cell-level performance.

• Education, where LTE MAC Lab serves as an environment to visualize LTE network operation.

LTE MAC Lab architecture and deliverables

Deliverables: • LTE MAC Lab is delivered as a

Toolbox operating under MATLAB environment,

• It consists of m-, mex- and p-files, • Substantial parts of the code are

open for the customer modification,

• All functions have well-defined interfaces with described parameters, which make it possible to replace them with proprietary customer’s implementation.

Technical Specification Summary

• LTE specific features: – Carrier Aggregation (3GPP LTE Rel. 10) – Heterogeneous Network (multicell environment with diverse parameters of

the eNBs) – LTE channel bands: 700 - 3000 MHz – All LTE bandwidths: 1.4MHz, 3MHz, 5MHz, 10MHz, 15MHz, 20MHz

• Simulator features: – Dedicated functions for user defined algorithms (i.e. open API) – Downlink transmission – RRM Functionalities: scheduling (PF, RR, ISW proprietary), link adaptation,

handover, carrier activation/deactivation – Users Mobility Models: Random Direction Model, Random Way Point

Model;

• Link model: – Pathloss models: Modified Okumura – Hata model, 3GPP TS 36.942 Model,

Winner Model, COST 231 Model; – Multipath models: 3GPP TS 36.942 Model, Winner Model, Random

Distribution Model; – Environments: Rural, Urban, Suburban; – Antennas Characteristic Model; Omnidirectional Characteristic, 1 or 3

Sectors Characteristic

LTE MAC Lab

Simulation scenarios

Main simulation parameters

Parameter Value

Simulation length 100 ms (TTIs)

SINR mapping model MIESM

Simulated area size 300m x 300m

Pathloss model 3GPP TS 36.942

Multipath model 3GPP TS 36.101

Number of UEs 10

Mobility of UEs low

Tx power of the eNB 46 dBm

Antenna characteristics Omnidirectional

Carrier frequency 800 MHz

Bandwidth 5 MHz

Scheduling algorithm Round Robin

Simulated cases

• Benchmark scenario – Single cell

– Single carrier

• Two-carriers scenario – Single cell

– Two carriers

• HetNet scenario – Large cell

– And small cell (BW = 5 MHz, fc = 800 MHz, Tx Power = 30 dBm)

• Scheduling comparison – Round-robin

– ISW-proprietary

IS-Wireless

ul. Puławska 45b,

05-500 Piaseczno / near Warsaw,

Poland, EU

phone fax

web e-mail

+48 22 213 8297 +48 22 213 8298 www.is-wireless.com [email protected]

CONTACT DETAILS

system-level modelling: is-wireless tutorial on ieee globecom 2015

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