Characterizing mmWave Channels Greg VanWiggeren, … · wireless spectrum auction ... Digitizer Rubidium Clock M9362 ... (e.g. for 5-us delay spread) Real-time streaming to

Characterizing mmWave Channels for 5G

Greg VanWiggeren, Ph.D.

Hongwei Kong

Zhu Wen

Keysight Laboratories

Nov 16th, 2015

Page Outline

– Why mmWaves?

– Properties of mmW channels

– Channel sounding techniques

– Early experimental results from Keysight Labs

– Summary

IEEE 5G Summit 2

11/16/2015

Page IEEE 5G Summit 3

11/16/2015

Historical Context

1G 2G 3G 4G

100X

Data Rates

1000X

Capacity 100X

Densification

1ms Latency

Reliability

99.999%

100X

Energy Efficiency Digital

Voice Analog

Voice Mobile

Internet

First Mobile

Broadband Ubiquitous

Connectivity

5G

5G vision represents revolutionary change


11/16/2015

Achieving the 5G Vision More capacity is needed

100X

Data Rates

1000X

Capacity

100X

Densification

1ms Latency

Reliability

99.999%

100X

Energy Efficiency

• ~ 700 MHz total BW

• < 3 GHz

0 20 40 60 80 Frequency (GHz)

0

10

20

30

2014 2015 2016 2017 2018 2019

Exabyte

s /

Month

Worldwide Data Usage

Source: Cisco VNI Mobile, 2015


11/16/2015

Achieving the 5G Vision More capacity is needed

100X

Data Rates

1000X

Capacity

100X

Densification

1ms Latency

Reliability

99.999%

100X

Energy Efficiency

• ~ 700 MHz total BW

• < 3 GHz

0 20 40 60 80 Frequency (GHz)

Headline from cnet.com, January 2015

“FCC rakes in $45 billion from

wireless spectrum auction…”


11/16/2015

mmWaves for 5G A key enabler of the 5G vision

100X

Data Rates

1000X

Capacity

100X

Densification

1ms Latency

Reliability

99.999%

100X

Energy Efficiency

mmWave band properties:

• Wider bandwidths

• Higher path losses

• Different channel properties

0 20 40 60 80

Frequency (GHz)

28

37,3

9

64

-71

71

-76

81

-86

57-6

6

Page Outline

– Why mmWaves?




– Summary

IEEE 5G Summit 7

11/16/2015

Page

Challenges with mmW Channels

IEEE 5G Summit

Higher Path Loss

8

11/16/2015

For a dense network, atmospheric absorption is a minor issue

Report ITU-R M.2376-0

(06/2015)

Page

Challenges with mmW Channels

IEEE 5G Summit

Primary Source of Higher Path Loss

9

11/16/2015

= 𝑃𝑜𝑤𝑒𝑟𝑇𝑥 + 𝐺𝑎𝑖𝑛𝑇𝑥 + 𝐺𝑎𝑖𝑛𝑅𝑥− 20log 𝑑2 − 20log 𝑓2

From the Friis equation:

𝑃𝑜𝑤𝑒𝑟𝑅𝑥

Frequency

• Higher frequencies smaller antenna elements

• Higher directivity overcomes path losses

• Massive MIMO enabled in small size

• Some challenges

• Discovery and tracking

• Added complexity

Page

mmW Channels

IEEE 5G Summit

Dramatically different than channels below 6 GHz

10

11/16/2015

mmW Channels:

• Higher path losses

• Less diffraction

• Objects are more reflective

• More Doppler

• Greater penetration losses

(indoor/outdoor)

Industry needs for mmW models:

• Indoor and outdoor

• Urban canyons, stadium,

shopping mall

• MIMO (array) behavior

• Consistency with < 6 GHz models

to allow system performance

comparisons

Page Outline

– Why mmWaves?




– Summary

IEEE 5G Summit 11

11/16/2015

Page

Basic Channel Sounding

IEEE 5G Summit 12

11/16/2015

)(th

)()()( txthty

Page

MIMO Channel Sounding

IEEE 5G Summit

Conceptually similar but more subscripts

13

11/16/2015

)(th

)()()( txthty

MIMO mmW

Channel Model

txthty iijj )(

ty j txi

thij

Page

Channel Sounding Options

IEEE 5G Summit

Three valid approaches

14

11/16/2015

Frequency Swept

• Low speed measurement

• Challenging for widely separated Tx and Rx

Sliding Correlator


• Some temporal aspects not captured

Wideband Correlation

• Fast measurements

• Amp./phase information supports AoD, AoA meas.

Techniques

RF Channel

)(ty)(tx

)(th

Page


IEEE 5G Summit


15

11/16/2015

Frequency Swept



Sliding Correlator






Techniques

RF Channel )(ty)(tx

)(thSliding

correlator

receiver T. S. Rappaport et al., “Millimeter wave mobile communications

for 5G cellular: It will work!” IEEE Access, May 2013.

Page


IEEE 5G Summit


16

11/16/2015

Frequency Swept



Sliding Correlator






Techniques

RF Channel )(ty

)(th

)(tx

)()()(

)()()()()(

)()()(

thtxty

txtxthtxty

txthty

Page

Techniques for angular channel characterization

IEEE 5G Summit

Rotating horn antennas

17

11/16/2015

Tx Rx

Horn Antenna Horn Antenna

1st Line-of-Site Path

2nd Path

n2 measurements

𝜃𝐴𝑜𝐷 𝜃𝐴𝑜𝐴

Page

Techniques for angular channel characterization

IEEE 5G Summit

MIMO Sounding

18

11/16/2015

Tx Rx

MIMO Array MIMO array

1st Line-of-Site Path

2nd Path

1 measurements

𝜃𝐴𝑜𝐷 𝜃𝐴𝑜𝐴

Page Outline

– Why mmWaves?




– Summary

IEEE 5G Summit 19

11/16/2015

Page

Keysight MIMO mmW Sounding Architecture

IEEE 5G Summit

Preferred approach

20

11/16/2015

Wideband

Tx

RF Channel

Wideband

Multichannel

RX

txi ty j

txthty iijj )(

thij

MIMO mmW

Channel Model

Page

MIMO mmW Channel Sounder

IEEE 5G Summit 21

11/16/2015

E8267D

mmWave

Signal

Source

ANT PA

M9703A

8CH

Digitizer

Rubidium Clock

M9362

50 GHz 4CH Digital

Coherent Down Convertor

E8257D 67GHz LO

BPF

33512

AWG

LNA

L4450A Digital

I/O Switch

Controller

85332B 50GHz

SP4T Switch

RF Channel

Up to 44 GHz ANT

M8190A

5-GHZ

AWG

Rubidium

Clock HJ5418B

Page

MIMO mmW Channel Sounder

IEEE 5G Summit 22

11/16/2015

E8267D

mmWave

Signal

Source

ANT PA

M9703A

8CH

Digitizer

Rubidium Clock

M9362

50 GHz 4CH Digital

Coherent Down Convertor

E8257D 67GHz LO

BPF

33512

AWG

LNA

L4450A Digital

I/O Switch

Controller

85332B 50GHz

SP4T Switch

RF Channel

Calibration and synchronization ANT

M8190A

5-GHZ

AWG

Synchronize

Antenna Calibration

Rubidium

Clock HJ5418B

Page

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

x 10-6

-80

-70

-60

-50

-40

-30

-20

-10

0

Sample

Am

plitu

de (

dB)

Sounding Sequence Autocorrelation (Meas.)

MIMO mmW Sounding Signal Autocorrelation

IEEE 5G Summit 23

11/16/2015

Experimental vs. simulation

Simulation

Sounding Sequence Autocorrelation Sounding Sequence Autocorrelation

Measured by Channel

Sounder RX (M9703A) A

mplit

ude (

dB

)

-60

-40

-20

0

-80

Am

plit

ude (

dB

)

0

-100

-200

-300

Page

MIMO mmW Sounder Data Handling

IEEE 5G Summit

Broadband channel sounding leads to huge data sets

24

11/16/2015

MIMO mmW

Channel Model

M9703A: 4 Channels @ 3.2 GS/s

= 3.2 GS/s * 2B/S*4

= 25.6 GB/s

= 200 Gb/s

Very difficult to store

or stream out in real-time!!!


11/16/2015

Fortunately, the M9703A has

four FPGAs for streaming

data reduction

Broadband channel sounding leads to huge data sets

MIMO mmW Sounder Data Handling

ADC

ADC

ADC

ADC

ADC

ADC

ADC

ADC

FPGA

FPGA

FPGA

FPGA

Customer-programmable

FPGA “sandboxes” for

custom DSP

DSP includes:

• Digital down-conversion to I/Q

• Real-time autocorrelation

• Data-reduced complex impulse response

25.6 GB/s 1.6 GB/s

(e.g. for 5-us delay spread)

Real-time streaming to

storage now feasible.

Page

MIMO mmW Channel Modeling

IEEE 5G Summit

Parameter extraction using Keysight SystemVue

26

11/16/2015

MIMO mmW

Channel Model

Parameter extraction

using well-known

SAGE algorithm

• Angle of Arrival/Departure

• Power Delay Profile

• Rician K factor

• Doppler Shift

I/Q data from

the M9703A

Sounding

Data

Channel

Model

Page

MIMO mmW Channel Modeling

IEEE 5G Summit

Parameter extraction using Keysight SystemVue

27

11/16/2015

MIMO mmW

Channel Model

Sounding

Data

Channel

Model


using well-known

SAGE algorithm



• Rician K factor

• Doppler Shift

I/Q data from

the M9703A

Page

MIMO mmW System Simulation

IEEE 5G Summit

Enabled by SystemVue and channel measurements

28

11/16/2015

I/Q Waveform

TX System

Channel Model

RX System

EVM & BER

Sounding

Data

Channel

Model


using well-known

SAGE algorithm



• Rician K factor

• Doppler Shift

I/Q data from

the M9703A

Channel

Model

SystemVue Simulation Flow

Page

MIMO mmW Sounding Reference Solution

IEEE 5G Summit

MIMO Sounding (4 x 4)

29

11/16/2015

• Carrier Frequency: up to 44 GHz

• BW: 1 GHz

Transmitter Receiver

Keysight reference solution

Page

Reference Solution Results 28GHz, 4x4 MIMO, 1GHz BW

Tx

Rx

0 deg

0 deg

LOS

IEEE 5G Summit 30

LOS

Pa

th L

oss (

dB

)

11/16/2015

-50

-90

-70

Path

Loss (

dB

)

Path delay (ns)

0 500 250

Page

Reference Solution Results 28GHz, 4x4 MIMO, 1GHz BW

Tx

Rx

0 deg

-30 deg

LOS

IEEE 5G Summit 31

LOS

AOA changes

accordingly

Path delay (ns)

11/16/2015

0 500 250

-50

-90

-70

Path

Loss (

dB

)

Page

LOS

Reflection from

ceiling

Projector

Reference Solution Results 5.8GHz, 8x8 MIMO, 250MHz BW

Tx

Rx

0 deg

30 deg

Metal

Panel

Reflecting

path

LOS

IEEE 5G Summit 32

Projector

Reflection

from ceil

Transmitter

Receiver

11/16/2015

Keysight reference solution

45°

Page

Reference Solution Results 5.8GHz, 8x8 MIMO, 250MHz BW

Tx

Rx

0 deg

30 deg

Metal

Panel

Reflecting

path

LOS

IEEE 5G Summit 33

Projector

Reflection

from ceil

LOS (between

two samples)

Path delay (ns)

From panel

From projector

11/16/2015

-65

-130

-95

0 2000 1000 P

ath

Loss (

dB

)

45°

Page

• MIMO mmW channel sounding is key to enabling 5G mmW networks

• A diverse set of technologies is required:

• We demonstrated a calibrated sounder with 1-GHz BW and up to 44 GHz carrier.

The resulting channel model can be used for system simulation.

• This is an area of active research—we look forward to working with you.

Summary

IEEE 5G Summit

MIMO mmW Channel Sounding Reference Solution

34

11/16/2015

MIMO mmW

Channel Model

Documents

Characterizing mmWave Channels Greg VanWiggeren, … · wireless spectrum auction ... Digitizer Rubidium Clock M9362 ... (e.g. for 5-us delay spread) Real-time streaming to