A brief overview on both the technologies and their impact on the Next Generation Wireless Networks (NGN).

1. WiMAX vs LTE
Priyanka Gaggar
Priyadarshini
Khushboo Kalyani
Kunal Nadkarni
Ankush Gadodia

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

3. 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!!

4. Rise of Broadband
• Increasing use of broadband worldwide

5. Rise of Data traffic
• Major increase in data traffic includes multimedia content

6. Motivation for 4G
• Improve Spectral Efficiency
• Spectrum flexibility
• Higher peak data rates
• Lower infrastructure costs
• Lower Latency
• Improved capacity
• Deployment of Flattening architecture

7. 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,
NSN, Ericsson, Alcatel Lucent etc. are supporting LTE

8. 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.
• 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.

9. 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
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.

10. 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 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.

11. WiMAX architecture

12. 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.
• 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.

13. 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
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

14. LTE architecture

15. 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)
• 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

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

17. Differences
Point of difference WiMAX LTE
Subcarrier Spacing The subcarrier spacing can be Constant at 15kHz.
variable due to which capacity
can be varied.
Latency The time between the user-B.S.- The time between UE-RNC-UE
user is 50msec. is10msec.
Channel utilization optimizes for maximum channel organizes the available
usage by processing all the spectrum into smaller chunks.
information in a wide channel.
FFT Due to High channel utilization, Organization of data into
processing that much information smaller chunks makes it
requires 1000-point Fast Fourier process the information by a
Transform. lower point FFT (like 16-point
FFT).
Evolution It is a completely new technology It has evolved from WCDMA
with upgrading in generations but to HSPA to LTE with a core
not an exact evolution. backbone of GSM.

18. Differences
Point of difference WiMAX LTE
Duplexing mode Uses only TDD(Time Division Uses FDD(Frequency Division
Duplexing). However 802.16m Duplexing) and TDD(Time
release 1.5 added FDD feature Division Duplexing).
due to growing market
opportunities and to avoid
interference.
Uplink signaling WiMAX uses Orthogonal LTE uses single-carrier
Frequency Division Multiple frequency division multiple
Access (OFDMA) for uplink access (SC-FDMA) for uplink
signaling. signaling.
Power consumption Due to OFDMA on the uplink Due to SC-FDMA on the uplink
signaling the PAPR (Peak to signaling the PAPR is lower
Average Power ratio) hence more and PA efficiency is high hence
power consumption at the less power consumption and
handset. improved battery life.

19. Global Wireless Spectrum Allocations

20. 802.16d (Fixed WiMAX) deployments Worldwide
• Implementation at 2.3GHz, 2.5GHz, 3.3GHz, 3.5GHz and
5+MHz bands

21. 802.16e (Mobile WiMAX) deployments Worldwide
• Implementation at 2.3GHz, 2.5GHz, 3.3GHz, 3.5GHz and
5+MHz bands

22. LTE deployment worldwide
• LTE deployments in 700MHz to 2.3GHz band

23. Further development
LTE-A WiMAX 2.0
• Carrier aggregation • Higher spectrum efficiency
• Relaying to improve coverage through more advanced and
and reduce deployment cost. higher-order MIMO
• Extended multi-antenna solutions.
transmission • Higher peak and user data
• Coordinated multipoint rates
(CoMP) transmission/ • Seamless WiFi - WiMAX
reception handover
• Support for femto-cells
• Enhanced coverage in high
interference environments

24. Which is the future?
Parameter WiMAX LTE
Time advantage
Latency
3 GPP evolution
GSM, HSPA...now LTE
Integration with Intel
Economies of Scale
Developing countries
Power consumption
Different carriers, different scenarios

25. 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
AT&T and T-mobile will go into LTE’s favor by expanding the
95% of cellular network area with LTE.

26. 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.
• 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.

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

28. 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/376594-9925981
• 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

29. THANK YOU