5g versus 4g waveforms benchmarking based on link-level ... · 3 • 4g/5g introduction •...

5G versus 4G waveforms benchmarking based on link-level modeling tools and SDR hardware

applied in education and research

Dr. Sławomir Pietrzyk

Łukasz Kwiatkowski

IEEE GLOBECOM 2016 Industry tutorial

1

2

• 4G/5G Introduction

• Experimentation platform

• Realization and demonstration of use case scenarios

• Conclusions for education and research

2

Tutorial outline

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3

Tutorial outline

4

• Fundamentals of 4G waveforms – OFDM, SC-FDMA

• Framing and basic PHY signaling in LTE – FDD frame structure

– Physical and transport channels

– Reference and Synchronization signals

• Fundamentals of 5G waveform candidates – UFMC, GFDM

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4G/5G INTRODUCTION

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5

Fundamentals of 4G waveforms

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OFDM vs. OFDMA Comparison

S/P . . .

Subcarrier

Mapping . . .

IFFT . . .

P/S CP

insertion

Size M1 Size N = M1+…+MU

S/P . . .

Size MU

data

user 1 Mod

QAM

data

user U Mod

QAM

OFDM Transmitter

OFDMA Transmitter

Subcarrier

Mapping . . .

IFFT . . .

P/S CP

insertion

Size N = M

data

user Mod

QAM

Size M

S/P . . .

Single user

gets the whole

spectrum

Multiple users

share the whole

spectrum

(single user

gets only a part)

…..

…..

7

Advantages of OFDM Disadvantages of OFDM

+ Robust against Intersymbol Interference

+ Based on well known (I)FFT procedure

+ Simple equalization

+ Provides parallelism in the frequency domain

+ Suitable for providing various levels of QoS

+ Easy to combine with other schemes (MIMO, adaptivity)

- Requires tight synchronization (in time and frequency)

- Generates highly dynamical signal (high PAPR)

- Large CP overhead

SCFDMA Why Single Carrier?

S/P DFT . . .

.

.

.

Subcarrier

Mapping . . .

IFFT . . .

P/S CP

insertion

Time domain Frequency domain Time domain

Size M

Size N > M

Symbol transmission

over a single frequency carrier Single Carrier

Frequency Division Multiple Access Multiplexing of users done

in the frequency domain.

SCFDMA and OFDMA Similarities and Differences

SCFDMA is different from OFDMA SCFDMA is similar to OFDMA

similar structure and performance to

OFDMA - block based modulation

with CP

deliveres different time domain

signal (lower PAPR/SC properties)

requires different symbol

detection approach

channel-adaptive

subcarrier bit and power

loading not possible

additional FFT and IFFT

operations needed at Tx

and Rx

possible noise

enhancement due to

additional DFT

Resist to multipath

it equalizes channel impairments in

frequency domain (simple

equalization)

divides the transmission bandwidth

into subcarriers

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10

Framing and basic PHY signaling in LTE

E-UTRA Radio Frame Radio Frame Structure in Time

1 Radio Frame (10 ms)

1 subframe (1 ms)

1 slot (0.5 ms)

Slot =

7 OFDM symbols

(Normal CP)

CP CP CP CP CP CP Useful Part

CP Useful Part CP Useful Part CP Useful Part CP Useful Part CP Useful Part CP Useful Part CP Useful Part

1 OFDM symbol (83μs)

1 OFDM symbol (71μs)

Frame =

10 subframes

Subframe =

2 slots

Slot =

6 OFDM symbols

(Extended CP)

or

Useful Part Useful Part Useful Part Useful Part Useful Part

E-UTRA Radio Frame Radio Frame Structure in Frequency

1 Symbol in the frequency domain

Subcarrier (SC)

BW: 1.4MHz = 128 SC (72 useful SC)

3MHz = 256 SC (180 useful SC)





Smallest allocation

12 SCs (180kHz)

Guardband

(not used SCs) Guardband

(not used SCs)

DC subcarrier

(not used in DL)

Pilot subcarrier

(QPSK symbol)

Data Subcarrier

(QPSK/16QAM/64QAM symbol)

Useful Subcarriers

Downlink E-UTRA Radio Frame General Parts

1 slot (0.5 ms)

Control Region:

First 1-3 OFDM Symbols in subframe

PCFICH – OFDM symbol 0,

PHICH – OFDM symbol 0

PDCCH – the rest

PBCH – 4 OFDM symbols (0-3)

in slot 1 in subframe 0

Synchronization Signal:

2 OFDM symbols (5-6) in slot 0 and 10

P-SS – OFDM symbol 6 in slot 0 and 10

S-SS – OFDM symbol 5 in slot 0 and 10

BW

PDSCH – rest REs

DC

1 subframe (1 ms)

62

SCs

72

SCs

1 Radio Frame (10 ms)

12 SC

7 OFDM Symbols

RS RE

2 PRB

OFDM Subcarrier

OFDM Symbol

Guard Band

for P-SS and S-SS

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1

Fundamentals of 5G waveforms candidates

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5G Scenarios

Enhanced Broadband 10 Gbps with high cells density

mmWave. Fragmented spectrum

Massive MTC Multitude of devices.

Loose synchronization. Low energy.

Ultra-Reliable Latency < 1ms.

Robustness.

5G for Remote Areas Large coverage.

Sparse network nodes. Scarce backhaul links.

ni.com

• Master text styles

• Second level

o Third level – Fourth level

ni.com | 3

5G Vectors in Need of Prototyping

Improve bandwidth

utilization and latency by

evolving the Physical Layer,

e.g. with flexible numerology.

New Radio Access

Technologies (RAT)

Utilize potential of

extremely wide bandwidths

at frequency ranges once

thought impractical for

commercial wireless.

mmWave

Dramatically increased

number of antenna elements

on base station enabling

beamforming.

Massive MIMO

Consistent connectivity

meeting the 1000x

traffic demand for 5G by:

Densification

SDN

NFV

CRAN

Wireless Networks

Multicarrier Waveforms

DFT-s-OFDM

OFDM

FBMC-OQAM

SC-FDE

FBMC-FMT

CB-FMT

GFDM

UFMC

FTN

SE-FDM FBMC

GFDM-OQAM

WCP-OQAM

OFDM-OQAM

IA-PFT

Slide 4

5

GFDM Non-orthogonal waveform with wide range of flexibility.

FBMC FBMC is characterized by per-sub-carrier filtering, long filter lengths and is typically used in conjunction with offset QAM.

BFDM Subcarriers orthogonality replaced by dual transmit and receive pulses. Especially efficient in the random access scenario.

UFMC UFMC is a generalization of filtered OFDM and FBMC. Pulse shaping filter is applied to a group of conventional OFDM subcarriers.

5G Waveforms candidates

6

UFMC Overview

UFMC Universal Filtered Multicarrier

FBMC

Filter Based Multicarrier Filtered OFDM

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UFMC Overview

8

• sub-band filters – reducing the spectral side-lobe levels outside sub-band

UFMC Sub-band filters

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UFMC Sub-band filters

w w w. e w i n e - p r o j e c t . e u

Generalized frequency division multiplexing

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Basic features: • CP • Circular filtering • Block structure (w/o tails) • Multicarrier: K subcarriers • Time division: M subsymbols

Advanced features: • OQAM/QAM • Time windowing • Guard symbol

CP

…


Design Space of GFDM

GFDM

Flexible time-freq.

grid

FDMA/

TDMA/

CSMA

Modulation

e.g., QAM, OQAM

Guard symbol

Time windowing

Subcarrier circular filtering

11

Low Latency and/or Low PAPR

High mobility

Low OOB

Mix of Services

Non-orthogonality vs. orthogonality


Experimental Results

12

• Out-of-band leakage is around 30 dB better compared to OFDM

►Less interference to adjacent communication systems

13

New Waveforms vs. OFDM

UFMC GFDM

+ lower OOB + roubstness against ICI + low complexity of the receiver + suitable for short burst communication + able to operate with relaxed synchronicity Complexity? Latency?

+ flexibility in parameter settings + efficient usage of time-frequency resources + lower OOB + lower PAPR + more robust in velocity scenarios Complexity? Latency?

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1

Tutorial outline

2

• eWINE project – Overview

– ISW activity

• Link-level modelling tool – LTE PHY Lab

• Overview

• Block model

2

Experimentation platform

3

3

eWINE project

w w w . e w i n e - p r o j e c t . e u

Factsheet

Call: H2020-ICT-2015

Topic: ICT-12-2015 (FIRE+)

Type of action: RIA

Budget: 2.349 M€

Start: 1 January 2016

Duration: 24 M

Partners


eWINE empowers wireless network

experimentation

5

On-demand, end-to-end location- & context-aware wireless connectivity services

Elastic resource sharing in dense/small cells

Open and reconfigurable physical layer

eWINE designs elastic network intelligence solutions for 3 innovative showcases


Showcase 3

6

Depending on the context (LOS/NLOS) either a sub-6 GHz link or a

mmWave link is selected

Waveform parameters (time, frequency, pulse shaping filter, preamble,

etc.) are adjusted depending on the presence of e.g. LTE interference


Showcase 3

Outcomes

• Novel algorithms for estimation of radio propagation

characteristics (LOS/NLOS) from channel state

information (CSI) measurements

• Flexible wave form generation (GFDM & OFDM) for

FPGA (USRP-RIO) & many-core systems

• Investigation of the mutual influence of orthogonal

(OFDM/SC-FDMA) and non-orthogonal (GFDM)

waveforms

• Intelligence to switch between OFDM and 5G-GFDM-

mode, without exchanging the firmware

7


eWINE builds on top of FIRE and extends it

with cognitive loops intelligence

8

FIRE facilities

eWINE Intelligent Toolbox

eWINE

Grand

Challenge

• Objective

winner: 3000 € +

• Subjective

winner: 3000 €

• First runner-up:

1500 €

• Second runner-

up: 500 €

Stay tuned!

CREW

FIRE services

WiSHF L

Intelligent Repository

Action Intelligence

Composition

Data

Collection

@eWINE_project

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9

Link-level modelling tool

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• LTE PHY Lab is a link-level simulation tool running under MATLAB / Octave environment.

LTE PHY Lab Overview

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LTE PHY Lab Main Applications

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

by providing golden reference. • R&D, where LTE PHY Lab provides simulation framework.

• Development of MAC protocols and RF processing, LTE PHY Lab serves as

a reference model.

• Testing and Verification, where LTE PHY Lab provides test signal vectors.

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

12

LTE PHY Lab Technical Specification Summary

• Physical layer models of 3GPP Release 8 with substantial elements of Release 9 and 10 – Downlink and uplink (including RACH) support

– OFDMA and SC-FDMA end-to-end processing

• Channel models included (AWGN, SUI, E-UTRA 3GPP TS 36.101)

• Support for MIMO (SM (SU-MIMO), TX diversity)

• Support for carrier aggregation (for up to 5 CC)

• 5G capabilities: – UFMC modulator and demodulator

– Environment for developing novel waveform

• Interoperability with LTE MAC Lab - system level simulation tool

13

LTE PHY Lab Downlink processing

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1

Tutorial outline

2

• Setup overview

• Exemplary scearios and their educational aspects

• Waveform generation

• Comaprision of key measures and conclusions

2

Realization and demonstration of use case scenarios

3

• Received from our 5GNOW project partner

• Possible modification of following UFMC parameters: – Number of multi-carrier symbols per TTI

– Size of FFT

– Filter length

– Sideband attenuation

– Width of subband (as a number of consecutive subcarriers)

– Allocation width in number of subbands

– Subcarrier modulation scheme (BPSK/QPSK/16QAM/64QAM)

UFMC in LTE PHY Lab

4

Parameter name Value

Number of multi-carrier symbols per TTI 14

Size of FFT 512

Filter length 37

Sideband attenuation [dB] 40

Width of subband [subcarriers] 32

Allocation width in number of subbands 16

Modulation scheme QPSK

UFMC in LTE PHY Lab

5

UFMC vs OFDM - demo

Transport Channels and Control Info

processing

Physical Channels

processing

Resource mapping

UFMC Modulator

Transport Channels and Control Info

processing

Physical Channels

processing

Resource mapping

OFDM Modulator

6

Parameter name Value

Number of multi-carrier symbols per TTI 14

Size of FFT 512

Filter length 37

Sideband attenuation [dB] 30

Width of subband [subcarriers] 16

Allocation width in number of subbands 32

Modulation scheme QPSK

UFMC in LTE PHY Lab


symbol-level processing

bit-level processing

Block diagram of the GFDM transceiver

7

BCH ENC

(CC, LDPC)

bits2symMapper

PHY/MAC Interface

Channel Estimation

Framer SDR

D/A + RF

Sync: Time, Freq.,

Sampling

DEC

GFDM Modem

Training seq.

SDR RF & A/D

Demapper

BCH DEC PHY/MAC Interface

bit-level processing

symbol-level processing

Tx

Rx

Resource Mapper

Channel Equalization

GFDM Modem

CP/CS Windowing


Demo details

Parameter:

• Subcarrier K: 64

• All subcarrier allocated

• GFDM subsymbols M: 9

• Zero-forcing receiver

• QPSK

• Convolutional code, rate ½

8

Preamble Counter data Counter data Counter

GFDM block

t


Current Implementation

• Coding:

• Convolutional code rate ½

• QPSK

• Modulation:

• Subcarrier K: 8 – 512

• Subsymbols M: 3-15

• Cyclic prefix/suffix length: 0 – 2048

• Windowing length: 0 – 2048

• Preamble length: 0 – 2048

• Channel estimation done on Host

9


Targeted Implementation

• Adaptive coding:

• LDPC

• QPSK up to 256 QAM

• Flexible resource allocation:

• Insertion of the preamble

• Flexible resource map

• Channel estimation on FPGA

• MIMO spatial multiplexing

• Advanced GFDM receiver

10


Setup for OFDM and GFDM mutual

influence

11

NI PXIe-1082

NI PXIe-8133

(Win7)

NI PXIe-7965R

NI PXIe-7965R

NI PXIe-7965R

NI 5791 NI 5791 NI 5791

Power Combiner ZN2PD-63-S+

Power Splitter ZN2PD-63-S+ Spectrum

Analyzer

NI PXIe-7965R

NI 5791

Power Splitter ZN2PD-63-S+

LTE Tx GFDM Tx LTE Rx GFDM Rx

Baseband processing

Power Splitter

Power Splitter Power Combiner


Demonstrator

12

PC #1

LTE PHY Lab LTE DL Tx

USRP N2920

USRP 2953R

GFDM Tx

Power Combiner

Power Splitter

PC #3

LTE PHY Lab LTE DL Rx

GFDM Rx

Power Splitter

ThinkRF WSA5000

PC #2

Spectrum analyzer

USRP N2920

USRP 2953R

13

Setup scheme

GFDM

OFDM GFDM

OFDM GFDM

OFDM

frequency

frequency

frequency

po

wer

p

ow

er

po

wer

1





1

Tutorial outline

2

• Summary

• Other solutions for education and research – aLTErnative

– University Suite

2

Conclusions for education and research

3

Summary

LTE PHY Lab

Provides 4G and 5Greference waveforms

Cooperates with popular SDR front-ends

Environment for experimentation and

education

Granularity reflecting 3GPP specs

4

aLTErnative Overview

Open source LTE stack – UE and eNB available

Configurator (all-in-one solution)

Improved efficiency

Developed within

aLTErnative Productivity service

5

aLTErnative Key features

aLTErnative Key Features Include

COMMON

Usage of USRP SDR as RF frontend

Automated installation of LTE stack and all its dependencies

Professional service support

eNB

Easy eNB configuration Advanced eNB customization

options for power users Basic EPC + HSS functionality

UE

Bandwidth from 1.4 to 20 MHz Soft USIM support Act as computer LTE modem

6

• University Suite:

– complete platform for education on 4G/5G

– primarily targeted at research and educational institutions such as universities and training companies

– based on simulation tools: LTE PHY Lab and LTE MAC Lab (aLTErnative will be included soon)

University Suite Overview

7

University Suite Explanatory files

All the explanatory files (PDF format) follow the below structure:

• Exercise target

• Required background

• Theoretical introduction

• Setting up laboratory environment

• Warm up exercises

• Main exercise tasks

• Test questions

• Report content

8

University Suite

Theoretical background

and predefined excerises

System-level simulator

Link-level simulator

University Suite Components

Link-level specific:

• 4G/5G waveform processing

• Downlink and uplink transmitter

• Channel models

System-level specific:

• Environments

• Path loss models

• Multipath models

• Random Access procedure in M2M case

9

IS-Wireless

ul. Puławska 45b,

05-500 Piaseczno / near Warsaw,

Poland, EU

9

phone fax

web e-mail

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

CONTACT DETAILS

5g versus 4g waveforms benchmarking based on link-level ... · 3 • 4g/5g introduction •...

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