MIMO in 4G Wireless. Presenter: Iqbal Singh Josan, P.E., PMP Director & Consulting Engineer USPurtek LLC

MIMO in 4G Wireless Presenter: Iqbal Singh Josan, P.E., PMP Director & Consulting Engineer USPurtek LLC About the presenter: Iqbal is the founder of training and consulting firm USPurtek LLC, which specializes in providing Professional Engineering Services to telecom operators and network equipment vendors in the domain of Wireless Broadband and Enterprise Networks. Iqbal is a Senior Member of IEEE and a Licensed Professional Engineer, and has 6 years of experience in the industry, having held engineering and project lead positions with multinational companies in the US as well as India. Iqbal can be reached at iqbal.singh@uspurtek.com

MIMO in 4G Wireless MIMO Introduction Realizing Benefits from MIMO Antenna Diversity, Beamforming and SDM Applications of MIMO in WiFi, WiMax and LTE Future of MIMO

Introduction Multiple Input Multiple Output o Multiple Tx & Rx Antennas Multiple radio channels Tx Rx M N

Introduction Multiple Input Multiple Output o Multiple Tx & Rx Antennas Multiple radio channels

What came before MIMO? SISO o Single Input Single Output Tx Rx

What came before MIMO? SISO o Single Input Single Output

What came before MIMO? SIMO o Single Input Multiple Output Tx Rx N

What came before MIMO? SIMO o Single Input Multiple Output Tx Rx

What came before MIMO? MISO o Multiple Input Single Output Tx Rx M

What came before MIMO? MISO o Multiple Input Single Output

Finally MIMO! MIMO o Multiple Input Multiple Output

Interactive Question # Which Antenna configuration is depicted by the following figure?. SISO. SIMO 3. MISO 4. MIMO Rx Rx Tx Rx Rx

Promises of MIMO Robust Radio Channel o Effects of fading and multipath interference mitigated o No breaks in voice calls or data Higher Throughput o Faster downloads o More Mbps with existing spectrum and power Enables 4G Wireless Broadband applications o WLAN (IEEE 80.n/ad) o WiMAX (IEEE 80.6m) o LTE-A (3GPP Rel 0) I Is this handset in your future?

Realizing MIMO Promises Antenna Diversity o Receive Diversity o Transmit Diversity Beamforming Space Division Multiplexing (SDM)

Multipath Propagation Path 3 Path Path 0-30 I db Fading Tx Rx + = + = no signal

Multipath Propagation Path Path Inter Symbol Interference I (ISI) Path 3 s s Tx Rx Path 3 Path Path + + s, s s s s time

Receive Diversity Mitigates Effects of Multipath Propagation Enhances Signal to Noise Ratio (SNR) SIMO Configuration Tx λ/ λ/ Rx I Signals combined from multiple antennas

Receive Diversity Mitigates Effects of Multipath Propagation Enhances Signal to Noise Ratio (SNR) SIMO Configuration Tx λ/ λ/ Rx Selection I Combining

Receive Diversity Mitigates Effects of Multipath Propagation Enhances Signal to Noise Ratio (SNR) SIMO Configuration Tx λ/ λ/ Rx Equal Gain I Combining

Receive Diversity Mitigates Effects of Multipath Propagation Enhances Signal to Noise Ratio (SNR) SIMO Configuration Tx λ/ λ/ Rx Maximal Ratio I Combining

Transmit Diversity Redundant copies of signal transmitted across space and time Space Time Block Codes (STBC) used o 50 00 ns time delay inserted in transmission paths Mitigates Effects of Multipath Propagation Enhances Signal to Noise Ratio (SNR) MISO Configuration Ant 3 Ant Ant time

Interactive Question # What is not a benefit of Antenna Diversity?. Diversity Gain. Enhanced Signal to Noise Ratio 3. Increased Bandwidth 4. Redundant Copies of Signal

Beamforming Controls shape and direction of radio signals Used on Transmit or Receive Antenna Arrays Extends range of radio signals in a direction o Signals from multiple antennas add up constructively to maximize receiver gain Mitigates Effects of Multipath Propagation

Space Division Multiplexing (SDM) Different signals transmitted and received simultaneously over same RF bandwidth Exploits spatial separation provided by MIMO Configuration Achieves Higher Throughput Ideal for RF channels with High Signal to Noise Ratio (SNR) Tx λ / M X N MIMO λ / Rx M N

Space Division Multiplexing (SDM) Signal Path Coefficients (h.hmn) represent amplitude and phase response for each signal path o Determined during training sequence Tx generates known training signal Rx processes training signal to estimate path responses h hn h Tx λ / M X N MIMO h λ / Rx hm M hmn N

Space Division Multiplexing (SDM) MIMO channel represented as matrix of signal path coefficients, H Receivers use H - to spatially demultiplex the original transmitted signals o T = H - R Rx h h hm Tx Rx = h h hm Tx RxN hm hm hmn TxM R H T Received I Signals I MIMO Channel Transmitted I Signals

Interactive Question #3 Which technique will you recommend when the radio channel is very noisy (SNR is low)?. Space Division Multiplexing (SDM). Transmit Antenna Diversity 3. Space Time Block Codes (STBC) 4. Time Division Multiplexing (TDM)

Multiplexing Rate in MIMO Multiplexing Rate o Number of distinctive data streams that can be received correctly and simultaneously For MxN MIMO, it is the min (M,N) Base Station Single User 3 3 X MIMO Multiplexing Rate =

Diversity Gain in MIMO For narrow band system with slow fading o Product of M & N Base Station Single User 3 3 X MIMO Diversity Gain = 6

Multiplexing & Diversity Combo Trade Off is Possible For 5x4 MIMO ocase : Reliable Mode Multiplexing Rate = Diversity Gain = 3x = 6

Multiplexing & Diversity Combo Trade Off is Possible For 5x4 MIMO ocase : High Rate Mode Multiplexing Rate = 3 Diversity Gain = x =

MIMO in WiFi IEEE 80.n standard has adopted MIMO o Antenna Diversity upto 4 x 4 o Tx Beamforming o Space Division Multiplexing (SDM).4/5 GHz ISM band o 0/40 MHz Bandwidth PHY Data rates upto 600 Mbps o Throughput > 00 Mbps Extended Range o Indoor 70 m o Outdoor 50 m

MIMO in WiFi Antennas for Access Point o Narrowband Monopole λ / 4 λ/ λ/

MIMO in WiFi Antennas for Access Point o Multiband Compact Multiband Antenna Element 5 GHz.4 GHz Antenna Element Top View Ground RF Cable

MIMO in WiFi Antennas for Portable Devices o Tradeoffs between design, performance and placement Antenna Configuration: Case Ground Plane Antenna Feed Point

Interactive Question #4 What is the recommended physical separation between Antenna elements of a MIMO system?. λ/4. Depends on the wireless standard 3. Minimum λ/ 4. Does not matter

MIMO in WiMax IEEE 80.6m has full featured MIMO o Antenna Diversity o Beamforming o Space Division Multiplexing (SDM).3-.4, 3.3-3.4 GHz (country specific) o 5-0 MHz Bandwidth Enhanced Throughput o Gbps for fixed stations o 00 Mbps for mobile stations Single or Multi User MIMO o SU-MIMO o MU-MIMO

MIMO in LTE-A 3GPP Rel 0 (LTE-A) has full featured MIMO o Antenna Diversity o Beamforming o Space Division Multiplexing (SDM) Freq. bands covering 698-3600 MHz o Scalable Bandwidth (0-00 MHz) Enhanced Throughput o Gbps Downlink o 500 Mbps Uplink Single or Multi User MIMO o SU-MIMO o MU-MIMO

SU-MIMO Single User gets the benefit of full Throughput Base Station Single User 3 X MIMO 3

SU-MIMO Single User gets the benefit of full Throughput 3 X MIMO Base Station 3 Single User

MU-MIMO Multiple Users share full Throughput Base Station Multiple Users 3 3

A Glimpse of the Future Massive MIMO & WiGig (IEEE 80.ad) o 60 GHz unlicensed band 4 channels of GHz each o Upto 7 Gbps data rates o mm Wave MIMO Antenna Arrays small λ ( 5 mm) means very small antenna cm Distance between elements λ / =.5 mm

Bibliography An Introduction to MU-MIMO Downlink IEEE Communications Magazine, October 004 MIMO-OFDM based air interface IEEE Communications Magazine, January 005 Downlink MIMO in LTE-A IEEE Communications Magazine, February 0 Understanding IEEE 80.n amendment IEEE Circuits and Systems Magazine Q 008 Advancement of MIMO in WiMax IEEE Communications Magazine June 009 MIMO in WiMax and LTE IEEE Communications Magazine May 00 MIMO-OFDM Wireless Systems IEEE Wireless Communications August 006 Antennas for WiFi Connectivity Proceedings of the IEEE July 0 Overview of Mobile WiMax Technology and Evolution IEEE Communications Magazine October 008 The ARRL Handbook for Radio Communications, 00

Questions And Answers A copy of the slides from this seminar will be made available to you Information to claim PDH and Certificate of Completion o Visit http://bit.ly/mimoforum where you will be required to complete a feedback form respond to a problem statement from this seminar and your Certificate of Completion will be e-mailed to you within business days Presenter: Iqbal Singh Josan, P.E., PMP, USPurtek LLC o iqbal.singh@uspurtek.com o LinkedIn: http://www.linkedin.com/in/iqbalsinghjosan o Twitter: @uspurtek Visit us at http://uspurtek.com to learn more about our upcoming webinars and on-site training services

Upcoming Free Webinars Antenna Engineering: Part of o Saturday, Nov 3, 0 :00 PM Eastern Time, Duration: 60 min Learn the basics of Antennas - Understand practical Antenna Design Parameters, such as Directivity, Gain, Beamwidth, Aperture, Polarization, EIRP, Field and Power Patterns, Return Loss, Axial Ratio - Design considerations for cellular Base Station and Handset Antennas - Learn about different Antenna types and their characteristics - Understand Phased Array Antennas and Multiple Independent Beamforming - Learn about Smart Antennas and their applications Visit http://bit.ly/pwq6zp to register

Upcoming Free Webinars Antenna Engineering: Part of o Saturday, Nov 0, 0 :00 PM Eastern Time, Duration: 60 min Learn about the Antenna Design Process and Measurements of Impedance, Gain and Field Patterns in the Near and Far Field - Understand RF Site Surveys for Wireless LAN and Cellular Networks - Learn about different Antenna Diversity techniques and Diversity Combiners - Learn about techniques to expand Wireless System Capacity, such as Frequency Reuse, Cell Splitting and Cell Sectoring - Understand Flexible Frequency Reuse in 4G LTE networks - Learn about overlay macrocell networks and Femto Cells in 4G LTE - Understand MIMO techniques with diversity, beamforming and Space Division Multiplexing - Understand applications of MIMO in WiFi, WiMax and LTE Visit http://bit.ly/pwq6zp to register