This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
IMT‐A 4G capacity targets [ITU‐R M.2133]: 2.2b/s/Hz for downlink and 1.4b/s/Hz for uplink in urban deployment supported rate is thus maximal 100Mbps/km2 (500m cell size; 40MHz)
Capacity needs (reality check): peak density of 8,000 people/Km2 of which only 10% subscribe to the broadband service of which only 20% require access at the same time each requiring 5Mbps
4G requirements … … were short by a factor of 10 yesterday … are short by a factor of 50 today … will be short by a factor of 100 tomorrow
Increase in capacity over past decades:Martin Cooper: doubled every 30 months over past 100 years overall: million‐fold increase in capacity since 1957
Breakdown of these gains: 5 x PHY; 25 x spectrum; 1600 x reduced cells, 5 x rest
Breakdown of (estimated) cost:
Reduced Cells MHz
Reduced Cells MHz PHY
[HOT ‐ TOP 3 IEEE DOWNLOAD IN APRIL 2011] Mischa Dohler, R.W. Heath Jr., A. Lozano, C. Papadias, R.A. Valenzuela, "Is the PHY Layer Dead?," IEEE Communications Magazine, vol 49, issue 4, April 2011, pp 159‐165.
ETSI TC BRAN, TR 101 534: Alvarion, CTTC, Polska Telefonia Cyfrowa, Siklu, Thales "Very high capacity density BWA networks; System architecture, economic
Only viable solution is via change in architecture & smaller cells: Remote Radio Head: “dumb” radio extension of BS; often RF/IF/BB‐over‐fiber Relay: wireless radio extension of BS; often limited intelligence Pico Cell: intelligent BS; owned, planned and placed by operator Femto Cell: intelligent BS; mostly owned and placed by consumer; no planning!
• data region interference mitigation (a lot of work with viable solutions)• control region interference mitigation (surprisingly little work given it is
the actual problem since no control means no data)Source: Zubin Bharucha, DOCOMO Euro‐Labs
The proposal from DoCoMo Euro‐Labs advocates carefully selecting the PhysicalCell Identifier (PCI) of HeNBs at start‐up, such that any interference caused by theircontrol channels to the PCFICH of any trapped macro UEs is avoided.o In order for this to be possible, the HeNB needs to identify the eNB that it is
closest to. Identifying the eNB means that the HeNB must be aware of the PCI of the eNB
Qualcomm Proposition in BeFEMTO for Resource Partitioning in Space for Femto‐Macro Interference Mitigation:
Problem Statement: proper resource partitioning is a must to handle femto‐macro interference beam selection in MIMO‐enabled femto BS equipment could be made use of
Innovative Proposition: design of suitable coordinated beam selection algorithm following LTE codebook designs comparative study between different restriction and codebook policies study outcomes: codebook restrictions yields gains to macro users at low femto capacity loss
With femtocells, the degrees‐of‐freedom (DOF) increase significantly – and with it complexity! [presented by Interdigital: Globecom’11 – IWM2M, Houston]
SON Helps For Previously Manual Processes: reduce manual intervention for deployment savings automate repetitive processes examples: automatic planning & self‐configuration
SON Helps For Too Fast/Complex Processes: improve run‐time operation based on real‐time data automate optimization of critical network elements example: self‐optimization & self‐healing
Among the many possible approaches, we deal with cognitive/docitive RRM to facilitate SON.
From cognitive to docitive networking paradigms: cognition: “system which is working under conditions it was not designed for” docition: “teaching” between expert nodes to accelerate learning/cognition result: truly autonomous SON with quick convergence
Operator’s capacity challenge today and for next years: capacity requirements are far off realityexcept for order‐of‐magnitude PHY, rather work on architectureinfrastructure cost is major driver since ROI margins tightenmanagement becomes major problem, SON is a must
1Gbps/Km2 architecture with the following properties...… LTE(‐A) & WiMAX‐agnostic architecture... anytime and everywhere in urban environments… cost‐efficient to operators, service providers, users… spectrally efficient using both licensed and exempt bands... autonomous operation facilitating deploy & forget experience
Heterogeneity Is Quickly Increasing:femtos, networked femtos, wifi, m2m, etc, etcfuture use outdoors, mobile, in relay formallow for viable QoS/QoE delivery
Self‐Organizing Networking Will Be Key:distributed localized SON (important for signaling)standards compliant SON approaches for industry uptaketake energy constraints into account
Business Models subscriber models FON‐like approaches
Besides my own, many third party copyrighted material – mainly from the BeFEMTO Femtocell Winterschool 2012 & BuNGee project – is reused within this tutorial under the 'fair use' approach, for sake of educational purpose only, and very limited edition.
As a consequence, the current slide set presentation usage is restricted, and is falling under usual copyrights usage.
CTTC working with Ubiquisys, the leading femtocell manufacturer: develop a common platform for LTE femto/macro cell vendors to evaluate their different solutions open source to foster adoption/contributions; based on NS‐3; http://iptechwiki.cttc.es/LTE‐EPC_Network_Simulator_(LENA) use case: LTE‐based Self Organized Networks need to test SONs algorithms before deployment Ubiquisys made extensive use of simulation to design its first generation of WCDMA intelligent femtocells
Product–oriented:Real‐world interfaces for SON algorithmsFemtoForum MAC Scheduler API specification