WiMAX vs LTE

WiMAX vs LTE

Priyanka GaggarPriyadarshiniKhushboo KalyaniKunal NadkarniAnkush Gadodia

Introduction

• Need to go beyond 3G• Wireless Interoperability for Microwave Access (WiMAX)• Long Term Evolution (LTE)• Global perspective

Wide spread use of Broadband

• Widespread usage of the ‘INTERNET’• Hunger for more speed and better quality of service.• Shift from landline Broadband to Smart phones and Tablets for faster and ease of access to the internet.

• Broadband Wireless- The next big thing!!

Rise of Broadband

• Increasing use of broadband worldwide

Rise of Data traffic

• Major increase in data traffic includes multimedia content

Motivation for 4G

• Improve Spectral Efficiency• Spectrum flexibility• Higher peak data rates• Lower infrastructure costs• Lower Latency• Lower Latency• Improved capacity• Deployment of Flattening architecture

Battle of the Megabytes• WiMAX vs LTE- Clash of the Titans• WiMAX- An IP based wireless broadband access technology that provides performance similar to Wi-Fi with coverage and QoS (Quality of Service) of cellular networks.• Cellular-backed LTE, with overwhelming support from cellular operators, looks to be late starting favorite• Intel, Samsung, Cisco etc. are supporting WiMAX whereas, • Intel, Samsung, Cisco etc. are supporting WiMAX whereas, NSN, Ericsson, Alcatel Lucent etc. are supporting LTE

WiMAX introduction

• Need for the extension of the range of Wi-Fi• Key to Wi-Fi’s success: 1. Simple Time Division Duplex protocol and flat IP

architecture.2. Base station could be plugged into simple DSL line.2. Base station could be plugged into simple DSL line.• Goal of WiMAX- to extend Wi-Fi like services to an entire

community by using inexpensive components and licensed or unlicensed frequencies.

• Roger Marks founded 802.16 (WiMAX) working group in 1998 and has chaired the committee since then.

• WiMAX combines the cellular range with the Wi-Fi speed. It plugs into Ethernet like Wi-Fi and provides roaming voice and data like cellular.

WiMAX standards• First wireless MAN air interface standard in 2001 (use above 10GHz)- approved WiMAX 802.16a original WiMAX specs in January 2003

• Followed by 802.16d (fixed WiMAX) in 2004 which added the MIMO.

• Further came in 802.16e (mobile WiMAX) which added the • Further came in 802.16e (mobile WiMAX) which added the mobility factor

• Current version is 802.16j which added multihop relay• Future standards of 802.16m, 802.16n and 802.16p are in progress which will bring in advanced air interface with higher data rates of 100mbps for mobile and 1Gbps for fixed services along with higher reliability of network and FDD along with TDD.

WiMAX specifications• Distances up to 50kms (30 miles) for point to point(line of sight) communication and up to 8kms (5miles) for point to multipoint (non line of sight) communication

• 20MHz WiMAX channel - speeds of up to 75Mbps(theoretically) for users near the B.S. , practically only up to 45Mbpsup to 45Mbps

• Frequency reuse and B.W. range from 1.5MHz to 20MHz• It uses licensed spectrum of : 2.3GHz, 2.5GHz and 3.5GHz as well as unlicensed spectrum of 3.65GHz and 5.8GHz.

WiMAX architecture

LTE explained

• Evolves form third generation technology based on WCDMA.• Supports higher peak data rate through wider bandwidth.• Provides Low Latency and Overhead (Radio Delay<5mSec)• Implements Scheduling at Base station to maintain Channel Quality.Quality.• All IP based network with reduction in cost per bit• Flexibility in use of new and existing frequency bands (Spectrum Flexibility)• Lower power consumption• Supports mobility speeds up to 350km/hr with 500km/hr under consideration.

LTE architecture• Provide open interface to support multi vendor deployments• Provide robustness – no single point of failure• Support Multi- RAT(Radio Access Technology) with resources controlled from the network

• Support of seamless mobility to legacy systems as well as to other emerging systems including Inter-RAT handover and other emerging systems including Inter-RAT handover and service based RAT selection.

• Maintain appropriate level of security.• LTE makes use of new e-NodeB’s and gets rid of the use of RNC.

• Simple network architecture with open interfaces

LTE architecture

LTE specifications• Higher Peak data rates(20MHz operation): downlink: 100Mbps (150Mbps peak based on 2x2 MIMO)(300Mbps peak based on 4x4 MIMO) uplink: 50Mbps(75Mbps peak) (5Mbps individually)• Improved latency (UE-RNC-UE) below 10ms (round trip time)• Improved latency (UE-RNC-UE) below 10ms (round trip time)• Support of scalable B.W. – 1.4,3,5,10,15,20MHz• Support of paired and unpaired spectrum (FDD and TDD)• Uplink: QPSK, 16-QAM and 64-QAM (optional for handset)• Downlink: QPSK, 16-QAM and 64-QAM• Uplink- SC-FDMA and Downlink- OFDMA

Similarities

• OFDMA(Orthogonal Frequency Division Multiple Access) on downlink• MIMO(Multiple Input Multiple Output) and beam forming• Backward compatibility• Speed• Speed• Error correcting codes- Viterbi and turbo coding• IP based technologies• Scalable Bandwidth

DifferencesPoint of difference WiMAX LTESubcarrier Spacing The subcarrier spacing can be

variable due to which capacity can be varied.

Constant at 15kHz.

Latency The time between the user-B.S.-user is 50msec.

The time between UE-RNC-UE is10msec.

Channel utilization optimizes for maximum channel usage by processing all the

organizes the available spectrum into smaller chunks.usage by processing all the

information in a wide channel.spectrum into smaller chunks.

FFT Due to High channel utilization,processing that much information requires 1000-point Fast Fourier Transform.

Organization of data into smaller chunks makes it process the information by a lower point FFT (like 16-point FFT).

Evolution It is a completely new technology with upgrading in generations but not an exact evolution.

It has evolved from WCDMA to HSPA to LTE with a core backbone of GSM.

DifferencesPoint of difference WiMAX LTE

Duplexing mode Uses only TDD(Time Division Duplexing). However 802.16m release 1.5 added FDD feature due to growing market opportunities and to avoid interference.

Uses FDD(Frequency Division Duplexing) and TDD(Time Division Duplexing).

Uplink signaling WiMAX uses Orthogonal LTE uses single-carrier Uplink signaling WiMAX uses Orthogonal Frequency Division MultipleAccess (OFDMA) for uplink signaling.

LTE uses single-carrier frequency division multiple access (SC-FDMA) for uplink signaling.

Power consumption Due to OFDMA on the uplink signaling the PAPR (Peak to Average Power ratio) hence more power consumption at the handset.

Due to SC-FDMA on the uplink signaling the PAPR is lower and PA efficiency is high hence less power consumption and improved battery life.

Global Wireless Spectrum Allocations

802.16d (Fixed WiMAX) deployments Worldwide

• Implementation at 2.3GHz, 2.5GHz, 3.3GHz, 3.5GHz and 5+MHz bands

802.16e (Mobile WiMAX) deployments Worldwide

• Implementation at 2.3GHz, 2.5GHz, 3.3GHz, 3.5GHz and 5+MHz bands

LTE deployment worldwide

• LTE deployments in 700MHz to 2.3GHz band

Further developmentLTE-A

• Carrier aggregation• Relaying to improve coverage and reduce deployment cost.

• Extended multi-antenna

WiMAX 2.0

• Higher spectrum efficiency through more advanced and higher-order MIMO solutions.• Extended multi-antenna

transmission• Coordinated multipoint (CoMP) transmission/ reception

• Higher peak and user data rates

• Seamless WiFi - WiMAXhandover

• Support for femto-cells• Enhanced coverage in high interference environments

Which is the future?Parameter WiMAX LTE

Time advantage

Latency

3 GPP evolutionGSM, HSPA...now LTEGSM, HSPA...now LTE

Integration with Intel

Economies of Scale

Developing countries

Power consumption

Different carriers, different scenarios

AT&T acquires T-Mobile for $39 billion (3/20/11)

• The acquisition will bolster AT&T's dominance with the addition of more than 33 million subscribers to its 95.5 million customer user base, giving it a new total of more than 129 million subscribers.• As far as the US telecom market is concerned this merger of • As far as the US telecom market is concerned this merger of

AT&T and T-mobile will go into LTE’s favor by expanding the 95% of cellular network area with LTE.

ZTE demonstrates WiMAX and LTE on the same network (4/21/11)

• If both of them are used on the same network then you get the best of both worlds and can imagine the increased level of possibilities and network robustness that can be achieved.• ZTE successfully demonstrated the same 2 weeks ago.• ZTE successfully demonstrated the same 2 weeks ago.• During the demonstration, ZTE said it used the same

WiMAX system to upgrade it to a TD-LTE system in less than an hour without replacing any hardware.• The demonstration proved that ZTE's base-stations

support a seamless upgrade from WiMAX to TD-LTE and that the company can provide a successful solution for the evolution for WiMAX and TD-LTE to co-exist.

Summary

WiMAX v/s LTE is not a battle after all…Both are here to stay!!!Both are here to stay!!!

References• http://www.dailywireless.org/2009/12/22/top-ten-wimax-lte-stories-

of-the-decade/• http://wimaxmaps.org/• http://www.wimax.com/lte/why-the-wimax-vs-lte-battle-isnt-a-battle• http://www.slideshare.net/CiscoSP360/comparison-of-lte-and-wimax• http://www.wimax.com/lte/why-the-wimax-vs-lte-battle-isnt-a-battle• http://www.linkedin.com/answers/technology/information-

technology/telecommunications/TCH_ITS_TCI/376594-9925981technology/telecommunications/TCH_ITS_TCI/376594-9925981• http://www.4gwirelessjobs.com/articles/article-detail.php?Analysis-

WiMax-&-LTE&Arid=MTA5&Auid=OTU=• Articles on “AT&T acquires T-Mobile for $39 billion” and “ZTE

demonstrates WiMAX and LTE on the same network”• White paper on “LTE release 8 and beyond”• Whitepaper on “Driving 4G: WiMAX & LTE”• IEEE communications magazine October 2008• IEEE communications magazine April 2009

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