the next generation wireless lan standard and … next generation wireless lan standard and overcome...

The Next Generation Wireless LAN Standard and Overcome the Test Challenges

Brian Su

Sr. Project Manager

Jun, 2017

PagePageAgenda– Overview of Wi-Fi Technology Evolution

– New Technologies and Test Challenges

• 802.11ax

• 802.11ad/ay

– New Topics for in IEEE 802.11

• Wake-Up Radio

• Light Communications

– Wi-Fi vs. 3GPP Unlicensed

– Q&A

Evolution of WLAN 2

Page

A Brief History of WLAN

Evolution of WLAN 3

Page

Wireless LAN today

Technologies keep evolving to meet the

newest requirements Fast Facts

– 2 Mbps to >1 Gbps in 15 years

– 5 M chipsets per day

– 38 Billion connected devices by 2020

– Average of 8 connected devices per

household

– $222 B in economic value / yr

– 60% of mobile traffic uses Wi-Fi

– 70% of all internet traffic uses Wi-Fi

Source: Wi-Fi Alliance & various

Evolution of WLAN 4

Page

Standard Groups

Evolution of WLAN 5

Page

Wi-Fi TechnologiesSupport a wide range of connectivity needs

Image courtesy of IEEE 802.11 Evolution of WLAN 6

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Evolution of 802.11 Standards

Standard Frequency

(GHz)

Bandwidth

(MHz)

Modulation Max Data

Rate

802.11b 2.4 22 DSSS 11 Mbps

802.11a 5 20 OFDM 54 Mbps

802.11g 2.4 20 OFDM 54 Mbps

802.11n 2.4, 5 20, 40 MIMO-OFDM 600 Mbps

802.11ac 5 20,40,80,160 MIMO-OFDM 7 Gbps

802.11ax 2.4, 5 20,40,80,160 MIMO-OFDM 10 Gbps

802.11ad 60 2160 OFDM, SC 7 Gbps

802.11ay 60 (2160) x2, x3, x4 OFDM, SC 20 Gbps

Note: Capacity is the key performance metric for Wi-Fi instead of theoretical peak rate.

Evolution of WLAN 7

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IEEE 802.11 Revisions


Page

Frequency Bands

802.11ad/ay802.11af

802.11ah

802.11b/g/n/ac/ax 802.11a/n/ax

802.11pUnlicensed

Licensed

0 Hz 70 GHz6 GHz

Evolution of WLAN 9

PagePageAgendaOverview of Wi-Fi Technology Evolution


• 802.11ax

• 802.11ad/ay


• Wake-Up Radio



– Q&A

Evolution of WLAN 10

Page

The Demand for High Efficiency Wi-Fi

Dense Wi-Fi deployments

Public access & offloading

Outdoor use & extended range

Large number of devices

Targeting 4x throughput increase per station in dense environments over 11ac.


Page

Key Features of 802.11axDesigned for high density connectivity with high overall

capacity

• Supports simultaneously serving lots of devices per AP

• Increases capacity and efficiency

• Improves device battery life

Uplink resource scheduling

• Efficiently serves multiple traffic types with multiple APs on shared channels

• MAC enhancements support newly introduced mechanisms

MU-MIMO and OFDMA

• Provide increased efficiency

Long OFDM symbols & higher order modulation

• For improved coverage

Extended guard interval coverage


Page

– Increase network efficiency by multiplexing users in both frequency

and space

20

MH

zPHY

Header

Time

Freq

Space

20

MH

z

STA#10

STA#35

STA#54

STA#26

Sub-

Band

OFDMA

STA #3

STA #8

STA #19

SS 1,2

SS 3,4,5

SS 6

MU-MIMO

Technical HighlightsMulti-user support: MU-MIMO and OFDMA

Frames are transmitted employing either OFDMA, MU-MIMO or a mixture of both

Image courtesy of Wi-Fi Alliance Evolution of WLAN 13

Page

Technical Highlights

– MU-MIMO

• Up to 8x8 MIMO in downlink and

uplink

• Serving up to 8 users

• For high-band applications

– OFDMA

• OFDM: use full bandwidth per user

• OFDMA: scales resource for different

types of traffic -> increase overall

efficiency, reduce latency

• For low-band applications

MU-MIMO & OFDMA: used based on application type


Page

Technical Highlights

Contention based resource

allocation for legacy WLAN tech.

– Un-coordinated resource

management

– Devices compete to get resource

until they succeed

Scheduling based resource

allocation 11ax

– UL resource allocation by AP

– A must for dense scenarios

– QoS

Target Wake Time (TWT)

• AP and device negotiate a specific time (awake) to access the medium,

otherwise device sleeps

• Reduce contention between users

• Increase the device sleep time to reduce power consumption

VS.

MU-MIMO and OFDMA: scheduled UL multi-user access


Page

IEEE 802.11ax PHY vs. 802.11ac How is it different from 802.11ac?

802.11ac 802.11ax

Frequency Band 5 GHz 2.4 GHz and 5 GHz

Bandwidths 20 MHz, 40 MHz, 80 MHz

Optional: 160 MHz, 80+80 MHz

20 MHz, 40 MHz, 80 MHz

Optional: 160 MHz, 80+80 MHz

Modulation Type Up to 256QAM Up to 1024QAM

FFT Size 64, 128, 256, 512

Sub-carrier space as 312.5 kHz

256, 512, 1024, 2048

Sub-carrier space as 78.125 kHz

OFDM Duration 3.2us + 0.8/0.4 us CP 12.8 us + 0.8/1.6/3.2 us CP

Multi-user

technology

MU-MIMO (DL),

up to 8 spatial streams

OFDMA + MU-MIMO (UL & DL),

up to 8 spatial streams

Data Rate Up to 7 Gbit/s (WAVE 2) Up to 10 Gbit/s

Key Performance

Metric

Peak rate driver

• Link throughput

• Aggregate throughput

User experience driver

• Average per station throughput

• Area throughput

• Power efficiency

Multi-user with OFDMA and SDMA


11ax Performance Enhancements vs. 802.11ac/n

Higher network throughput

• Particularly in crowded environments

Increased link efficiency

• Modulation

• Guard interval

Improved outdoor operation

• Guard interval

• Preamble

• Frequency diversity gain


Page

Test Challenges

Feature Description Test Challenges

Bands 2.4GHz and 5GHz Dual band

Channel

bandwidth

20 MHz, 40 MHz, 80 MHz,

160 MHz, 80+80 MHz

Need to generate and analyze wide BW signals

FFT size 256, 512, 1024, 2048 Smaller sub-carrier space(78.125KHz). More

sensitive to frequency and phase error and CFO

impact.

Modulation

types

Up to 1024QAM Need better EVM and better power amplifier

linearity

Spatial streams Max 8 More channels of signal generation and analysis,

up to 8x8, and MIMO channel emulator needed.

Multi-user OFDMA + MU-MIMO

Resource scheduling

Test simultaneous transmission and receiving for

multiple users and signal from each user would

experience different impairments.

More signaling test


Page

Signal Analysis

• 89600 VSA Software

• N9077A/B WLAN Application

SW platforms

Keysight 802.11ax Solutions for R&D and DVT

(N) N5182B MXG

Signal Generators N5182B MXG

Signal Generator

MXA

Signal Analyzer

PXA

Signal Analyzer

HW platforms:

Single Channel

HW platforms:

2x2, 3x3, 4x4, 8X8 MIMO

UXA

Signal Analyzer

Signal Generation: N7617B Signal Studio for WLAN

M9421A PXI VXT

M9421A PXI VXTM9421A PXI VXT

Vector Transceiver

M9421A PXI VXT

Vector Transceiver

Simulation: W1917EP WLAN Baseband Verification Library


EXM E6640A

11ax 8X8 MIMO with VXT(Blocker is optional used for rejection test)

8x8 MIMO

1. Blocker for receiver Adjacent/Non-

adjacent channel rejection test

2. Use 1 M9421A to transmit interference

signal as signal generator




802.11ax

• 802.11ad/ay


• Wake-Up Radio



– Q&A


Page

WiGig60GHz: 802.11ad/ay


11ad Features

High transmission speeds and low

latency

• 8 Gbps

• 60 GHz unlicensed spectrum

• 2.16 GHz channel width

Directional, in-room technology

• Reduced interference

• Better deployment in high density areas

• Increased physical security

Band switching for handoffs between

2.4/5/60 GHz

• Maintain link during changing session conditions

• Can select the most appropriate band

Data rates optimized for

different use cases

• Data rates change based on application


11ay Overview

Purpose• Achieve a maximum throughput of at least 20 gigabits per

second while maintaining or improving the power efficiency per station

Use Cases

• Access

• Cable replacement

• Wireless backhaul/fronthaul


11ay Technical HighlightsNext generation 60 GHz increases throughput, range and

reliability

– Channel bonding, contiguous and non-contiguous channel aggregation,

which requires

• Channelization

• Packet format

• Channel access

– SU and downlink MU MIMO

• Distribute capacity across users

• Unique requirements given directionality

• Exploit antenna polarization

• Changes to the beamforming protocol

– Others: OFDM and SC, A 64-point non-uniform constellation, LDPC…


Page

Challenges moving from RF to mmWave

Challenge Impact

Integration – change access

points

No RF connector, OTA only

Expensive equipment, hard to calibrate

IF and RF paths to characterize

Near/Far field – real world

testing with OTA, Antenna Size

dictates distance

Need a chamber with TRX near the DUT

Large chambers take space, expensive

Near field probing is time consuming (5~10x)

Beam steering – directionality

needs calibration

Phase cal is crucial to RF performance

Test device from 0 to 360o

Design it right or miss the market window

Link budget – high path loss at

60 GHz

Wide power range with low EVM floor

Tx with high power

Steerable beam antenna design

Throughput: Design high

volume mfg via OTA

More test points requires more time

Beam steering requires more calibration


11ad Test Solution802.11ad Non Signaling One Box Tester

Y7707A 802.11ad Application SW

Performs all tests in the 802.11ad standard

Runs inside the E7760A

M1650A mmWave Transceiver, 55 – 68GHz

Each M1650A is bidirectional and tunable

Includes 2 meter cable to deliver signals near the DUT

Single cable from E7760A provides the LO, power, and

control signals

E7760A Wideband Transceiver

1 VSA, 1 VSG in 2U form factor saves precious rack

space

2 x IFIO ports (SMA): 2 – 18 GHz

6x RF ports (Type N): 55 - 68GHz for mmWave

Tranceivers (M1650A)


Page

Challenges and SolutionsChallenge How Keysight can Help

Integration –

embracing the reality of

60 GHz and 2GHz BW

E7760A integrated solution (VSG,

VSA) with M1650A remote head (Tx

and Rx)

Troubleshoot IF and RF in 1

instrument

Near/Far field – real

world testing with OTA

E7760A + M1650A with 2m cable

Partnering for chambers and

fixturing

Beam steering –

directionality needs

calibration

E7760A w/ 6x M1650A, each w/it’s

own cal info

EEsof EDA modeling tools

Link budget – high path

loss at 60 GHz

E7760A+M1650A optimizes

settings to provide low EVM across

all power levels

Throughput Connect E7760A up to 6x M1650A

Chipset SW Automation tools



New Technologies and Test Challenges

802.11ax

802.11ad/ay


• Wake-Up Radio



– Q&A


Page

Wake-Up Radio


• Improves energy efficiency while maintaining low latency

Purpose

• 802.11 radios wake up periodically to receive data within latency requirement

• AP buffers data until 802.11 station wakes up

Solves the following problems

Page

Wake-Up RadioOperation


Page

Light Communications


PagePageAgenda

Overview of Wi-Fi Technology Evolution


802.11ax

802.11ad/ay

New Topics for in IEEE 802.11

Wake-Up Radio



– Q&A


Page

Wi-Fi vs. 3GPP unlicensedCellular Technologies extend into Unlicensed Spectrum


Page

Wi-Fi vs. 3GPP unlicensedWLAN and LTE competition on unlicensed band

Competition, complementary, or convergence in 5G?

Image courtesy of Qualcomm Evolution of WLAN 35

Page

IEEE and 5GWi-Fi’s role in delivering a “5G experience”

ITU Vision of 5G


PagePageAgenda

Overview of Wi-Fi Technology Evolution


802.11ax

802.11ad/ay

New Topics for in IEEE 802.11

Wake-Up Radio


Wi-Fi vs. 3GPP Unlicensed

– Q&A


Page

References

– 802.11 home page: http://ieee802.org/11/

– Wi-Fi Alliance http://www.wi-fi.org/

– Keysight WLAN solution: http://www.keysight.com/find/WLAN

– IEEE 5G: http://5g.ieee.org


http://ieee802.org/11/

http://www.wi-fi.org/

http://www.keysight.com/find/WLAN

http://5g.ieee.org/

the next generation wireless lan standard and … next generation wireless lan standard and overcome...

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