Upload
others
View
5
Download
0
Embed Size (px)
Citation preview
LTE and WiFi on the LESami Susiaho – Head of Edge Technologies, Sky Business, Sky UK
Cambridge wireless in London 17th September 2015Star Wars: The Empire Strikes Back
2
Overall picture of technologies
LTE-U
• Wild west LTE on 5 GHz
• In the US, China, India and Korea
• Ready, but requires hardware update
LAA-LTE
• Potentially polite LTE on 5 GHz
• Global when the standards are ready
• Details yet to be defined
• In the works, ready in 2016
LWA
• LTE using Wi-Fi to boost capacity
• Requires device and core software update only
Carrier Wi-Fi
• What Wi-Fi operators like The Cloud do now
• Best practice in Wi-Fi offload
• Ready, but improving
3
LTE-U - the Wild West standard of LTE on Wi-Fi spectrum
• Integration with Licensed LTE: supplemental
downlink (CA with uplink not needed)
• Coexistence with Wi-Fi: dynamic channel
selection and CSAT( based on LTE duty
cycle)
• No support for Listen Before Talk (LBT)
• Based on 3GPP release 10-12
• Not for EU but available in other markets,
such as China, Korea, India and the US
• Fewer changes from licensed LTE
• Earlier commercialization
4
LAA-LTE –the yet-to-be stamped future standard of LTE on LE
• Licensed Assisted Access – LTE
• Devices use licensed anchor band when
using Wi-Fi
• Wi-Fi like Coexistence with Wi-Fi: dynamic
channel selection and Listen Before Talk
• Based on 3GPP Release 13
• Compliant with regulatory requirements of
most countries
• Later commercialization
5
LWA - LTE and Wi-Fi aggregation or LTE with “Wi-Fi boost”
• Using both LTE and Wi-Fi to achieve the highest
possible capacity for mobile devices
• Proposed technology to be introduced in 3GPP
Release 13
• Uses the same 5 GHz spectrum as LTE-U or
LAA would and additionally, the 2.4 GHz band
• Crucially, LWA would not require any changes
for current Wi-Fi handsets or infrastructure, it
would be a software update
• Uses Wi-Fi only for downlink, LTE carrying all
uplink traffic and potentially, helping with the
downlink
• Both technologies played against their strenghts
6
Carrier Wi-Fi
• Carrier grade Wi-Fi has been the hot topic of many conferences and is getting a definition
• It is essentially, a Wi-Fi technology ideally suited for offloading data during peak times
• The Cloud estate is considered one of the most sophisticated Wi-Fi hotspot networks and
as such, often used as an example of a “Carrier grade Wi-Fi” network deployment
• Professionally deployed estate in high demand locations
• Technically advanced with scalable core, dual band Access points with smart antennas,
Passpoint ready, EAP-SIM ready, with central controller and sophisticated user
experience management
7
LTE has better spectral efficiency and coverage
• Dynamic link adaptation gives LTE a
slight advantage over Wi-Fi
• Furthermore, comparing IEEE
802.11ac and LTE Rel.12 at 256QAM
gives LTE an 11% advantage, with
WiFi at 6.67bits/symbol and LTE at
7.43bits/ symbol, respectively
• Time to market and market adoption,
scale of deployments and availability
of services being perhaps more
relevant measures
8
Co-existence work
• 3GPP work for co-existence with Wi-Fi has just started
• Concerns raised from IEEE/802.11 and WFA how the co-existence use cases are set up
and what scenarios are included
– Co-existence behavior with multiple overlapping deployments should be considered
– Test the networks with multiple clients, wide channels and
– LBT (Listen Before Talk) should be included with exponential back-off, in DL and UL.
– LBT timing rules and thresholds for energy detect that meld with Wi-Fi
– Preamble detection and/or reservation signaling
– KPIs other than just throughput and latency, such as Jitter, Packet loss, Frame retransmission rate,
beacon loss and deferral and power save signaling loss and deferral should be included
9
Relevance of 11% in the real world
• Difference between a good AP and a good AP can easily be
50% in performance and the range of minimum quality of
service
• Different configurations in LE deployments can quite easily
gain or lose much more than that
• Having said that, 11% addition to speed or range would be
welcome, but what about cost?
10
“Cost” of LTE on LE is unknown
And extremely hard to quantify
11
The real world of seamless user experience is a three dimensional
problem, not all of which are always considered
Wi-Fi
LTEOther Wi-Fi
12
Final thoughts
Wi-Fi is ready to deploy now
• Excellent coverage and capacity
• Low cost to deploy
• Excellent co-existence mechanisms with other
LE users
• Admission control, band steering, airtime
fairness and fast transition/roaming features
• 802.11ax, 802.11k&r, Passpoint and multiband
• Does not rule out the LTE deployments, or even
the LAA deployments
• Wi-Fi calling
• Perfect neutral host with 100% handset
adoption
LTE on LE is still in the works
• Deployments will likely introduce a hardware
change – further prolonging the adoption
timelines
• Higher cost to design and deploy
• Risk of harming other LE use cases
• Smallcell deployments are Wi-Fi like
Thank you
Star Wars: Return of the Jedi