BroadWay

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IST BroadWay A 5/60GHz hybrid system concept
2
Strategy for migrating towards higher frequencies

• The vision
• extend and complement 5GHz broadband wireless LAN
  systems in the 60GHz range for providing a new
  solution to very dense urban deployments and hot
  spot coverage without sacrificing the user
  throughput expectations
• guarantee nomadic terminal mobility in
  combination with higher throughput
• The key objectives
• bridge the 5GHz band and 59-65GHz bands by
  conceiving a dual frequency hybrid WLAN
• granting smooth evolution from existing 5GHz OFDM
  to 60GHz
• allowing backward compatibility to 5GHz systems
• providing total system throughput gt350Mbps
  through bandwidth expansion
• philosophy restrict proliferation of
  heterogeneous technologies, 60GHz HIPERSPOT based
  on extensions of current 5GHz OFDM hardware
• Leverage existing 5GHz products for a low cost
  60GHz product
• The BroadWay composite system is based on
• HIPERLAN/2 TDD/TDMA OFDM high spectrum efficiency
  technology _at_5GHz
• HIPERSPOT an innovative ad-hoc extension _at_60GHz
• HIPERLAN/2 and HIPERSPOT is the Way to Broadband
  communications BroadWay!

3
BroadWay project architecture and partners

• WP breakdown
• WP1 Application scenario and overall system
  specification
• WP2 Link layer, convergence layer architecture
  and implementation
• WP3 Advanced baseband architecture and key
  solutions
• WP4 Low cost integrated RF front-end and key
  solutions
• WP5 Industrial dissemination
• Partners major role
• Motorola (MOT)
• new baseband solution, provider of InP QMMIC
  technology, RF module design, ad-hoc
• Technische Universitaet Dresden (TUD)
• advanced baseband architecture (design,
  performance, prototyping)
• Farran (FAR)
• dual mode RF architectures antenna design joint
  antenna/RF-FE integration, system packaging
• TNO Physics and Electronics Laboratory (TNO)
• MAC extension for ad-hoc, 5/60GHz RF modules
  design and characterization
• Institut fuer Mobil und Satellitenfunktechnik GmH
  (IMST)
• antennas design at 5/60GHz
• Intracom (ICOM)
• Ad-hoc, routing preserving QoS, vertical hadoffs

4
Overall planning
5

• Ad-Hoc Networking issues
• in BROADWAY

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BroadWay Networking Summary

• A Centralized Architecture is considered
• the AP is responsible for all decisions
• Routing, Clustering, Neighborhood Discovery (ND)
  initiation
• information is collected at 5 GHz and is sent to
  the AP
• Clusters are created depending on
• geographical information (constructed by the ND
  phase)
• MTs that are close is possible to communicate
• the resource needs of the MTs
• MTs that need to exchange data are possible to
  communicate
• An enhanced protocol stack is defined to support
  the networking proposal in BroadWay

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The Cluster

• A Cluster
• operates at a specific channel at 60 GHz
• has a Cluster Head (CH) responsible for all
  communications
• consists of a number of MTs operating at the same
  channel at 60 GHz
• each MT can communicate with the CH
• is allowed to be active for a number of frames
  before switching to 5 GHz
• is possible to contain Forwarding Nodes (FN) to
  enable inter-cluster communication

Cluster Head
60 GHz Range
60 GHz Data Flow
Mobile Terminal
Intra-cluster Communication
Cluster Head
60 GHz Range
Forwarding Node
60 GHz Data Flow
Mobile Terminal
Inter-cluster Communication
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APs Supervision

• 5 GHz
• has the standard role of the AP
• is responsible to initiate a Neighborhood
  Discovery (ND) phase
• collects information
• neighborhood and resource requirements
• based on the collected information it decides
• on the clusters
• CHs, frequency channels, set of MTs, number of
  frames that a cluster is allowed to operate
• on feasible routes
• FNs are determined whenever it is feasible
• provides each CH, FN or MT at 60 GHz with
• routing and clustering information
• 60 GHz
• participates in ND phases
• is always a CH
• MTs close to the AP at 60 GHz always belong to
  its cluster

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Different Roles of a MT

• 5 GHz
• operates as standard MT
• receives messages from the AP
• to start a ND phase
• to become part of a cluster
• 60 GHz
• participates in ND phases
• CH receives corresponding message from the AP
  including
• clustering and routing information including
• FN receives corresponding message from the AP
  including
• clustering and routing information
• frequency channels of the adjacent cluster for
  the switching in between
• MT receives corresponding message from the AP
• similar role to that of the standard MT at 60 GHz
  (CH has the role of the AP at 60 GHZ)

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Finite State Machine for the different roles of a
MT
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Snapshot of BroadWay Network Architecture (BWNA)
AP
CH
Access Point
5 GHz Range
AP
Cluster Head
60 GHz Range
Forwarding Node
5 GHz Data Flow
Mobile Terminal
60 GHz Data Flow
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DLCCL Architecture for BWNA Support
Access Point
NCE Node Communication Entity
NCE
Cluster
prtpr
Specific
messages
MH
Ethernet
Information
CH_R_table
CH_C_table
BWSSCS
BWSSCS BroadWay Service Specific Convergence
Sublayer
MAC_ID_table
FN_table
NDI
BWR
Next ND
C_table
Phase
MTi
_table
MFL
BWRR_table
ND_table
NDP
RN
FL_table
BWDLC BroadWay Data Link Control
BWDLC
AP_table
ND
ND
messages
Control Plane
User Plane
Note MTs architecture is a simplified version
of the APs
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Modules, Tables and Information Flow

• BWDLC
• Neighborhood Discovery (ND) Discovers the
  connectivity between nodes at 60 GHz
• output AP_table (MTi_table for each of the MTs)
• BWSSCS
• Monitor Flows (MFL) Monitoring of the resources
  for a data session
• input MAC_ID_table, output FL_table
• Resource Needs (RN) Estimation of the resources
  for a data session
• input FL_table, output BWRR_table
• Neighborhood Discovery Processing (NDP) merging
  of ND information
• input AP_table plus MTi_tables, output ND_table
• Neighborhood Discovery Initiator (NDI) Decides
  on the next ND phase
• input ND_table, output Next ND Phase
• BroadWay Routing (BWR) Cluster and routing
  information
• input ND_table and BWRR_table, output C_table,
  FN_table
• NCE
• Message Handler (MH) responsible to send/receive
  information to the MTs
• input C_table and FN_table, output CH_C_table,
  CH_R_table, Cluster Specific information, prtpr
  messages

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BroadWay Routing (BWR)

• BWR is responsible for two major
  algorithms/decisions
• Clustering
• set of MTs that will form a cluster
• CH
• number of frames that a cluster is active
• Routing
• set of FNs
• Each of the above is subject to a particular
  trade-off

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BWR Trade-Off (1)

• Set of MTs present in a cluster
• MTs that are close and have data to exchange is
  not mandatory to belong to the same cluster
• other data connections might be open requiring
  data exchanges
• CH
• connectivity with all nodes in the network is
  required
• Increased number of frames that a cluster is
  active
• increased throughput
• - small amount of data needed to exchanged with
  MTs outside the cluster are delayed
• problem changes to topology (e.g. mobility)
  cause link failures
• if this is the case no increased throughput is
  achieved

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BWR Trade-Off (2)

• Set of FNs
• Switching between different channels at 60 GHz is
  required
• expensive
• Tight synchronization requirements
• each CH needs to be aware when a FN is present at
  its cluster
• Data traffic between clusters is forwarded
  through FNs
• they become the bottleneck link
• Ideas
• More than one FNs if possible
• Prioritization of their traffic

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Current BWR Algorithm

• So far a simple one
• step 1 check connectivity between two MTs
• step 2 check resource demands these two MTs
• step 3 if no other resource demand exists that
  step 1 is not satisfied then put those MTs in the
  same cluster
• step 4 elect as CH the MT that is connected with
  all MTs in the cluster
• Allow number of frames that are less than the
  next ND phase
• Extensive simulations will provide information
  for the fine tuning of BWR
• scheduled for the last 6 months of the project
  (6/04 until 12/04)