Transcript Flarion License Revenue: Target Vendors

Grand Challenges in Wireless
Wide Area Networks (WAN)
– A System Perspective
Junyi Li
Senior Director of Technology
Flarion Technologies
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Evolution of Wireless WAN
Converged IP Network
circuit-switched airlink
circuit-switched backbone
no built-in data capability
2x circuit-switched airlink
(RTT for voice, EV-DO for data)
2x circuit-switched backbone
(one for voice, one for data)
Single packet-switched airlink
over one packet-switched
backbone
From narrowband circuits-switched to mobile
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broadband packet-switched
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Competition in Wireless WAN
 Evolution of traditional cellular towards 3G (UMTS,
1xEV DO/DV)
 Evolution of WiFi towards WiMax: fixed 806.16a-d to
mobile 806.16e
 Emerging broadband mobile access (Flarion,
Arraycom, Navini, etc)
 In the near future, those systems may co-exist
because of technology, political and economic
reasons
 Challenges: service and system/device integration
– Seamless roaming
– Overlapping service areas
– Flexible programmable platform for development
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Challenges in Wireless WAN
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Users’ perspective
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Full mobility
Always-on connectivity
Predictable QoS throughout serving area
High bursty data rate
Low latency for interactive real-time applications
Transparent support of existing applications: no change to applications,
devices, protocols, or content
– Low battery consumption
– High airlink security
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Operators’ perspective
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A rich set of IP QoS based services and applications
A large number of simultaneous users each of predictable QoS
IP based standard network architecture and mobility management
Native multicast for bandwidth efficiency and streaming applications
Toll quality voice and “instant on” voice
Significant profitability in a high usage flat fee environment
3G/UMTS fails on economics and performance
WiFi falls short for ubiquity, mobility and competitiveness with DSL and
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cable – How about WiMax?
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Driving Forces
 Applications
– Web browsing may not be the dominate (killer) traffic
• Online gaming, streaming, PTT
• “The most important future uses of wireless communications
are unknown”
– How to make air interference sufficiently “flexible” to support
and mix all kinds of traffic requirement?
 Economics
– Pricing: how to induce higher network utilization and
generate more revenue?
– QoS: why does it matter? how to link it with user experience
(applications) and pricing?
 Devices
– How to increase battery life without sacrificing performance?
– Always-on connectivity?
– How to support a variety of high-end and low-end terminals?
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Open Issues
 Creative use of multiple antenna
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Low cost and low complexity
Mobile environment
Limited feedback signaling
Seamless support of heterogeneous devices
How to fit multiple antenna techniques into overall system picture?
 Uplink interference management
– How to accommodate or exploit bursty interference caused by
bursty traffic?
– How to jointly manage power control loop and traffic scheduling?
 Scheduling
– Downlink: well studied, but has room for improvement
• Spectral efficiency
• QoS
• Fairness
– Uplink: widely open
• Should uplink be scheduled or not?
• What is “uplink SNR”?
• How to signal uplink QoS requirement?
– Combining MAC state management and traffic scheduling
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