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Network Service Provisioning in UWB Open Mobile Access Networks. Dario Di Sorte , Student Member, IEEE , Mauro Femminella , Student Member, IEEE , Gianluca Reali , Associate Member, IEEE , and Sven Zeisberg , Member, IEEE.
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Network Service Provisioning in UWBOpen Mobile Access Networks Dario Di Sorte, Student Member, IEEE, Mauro Femminella, Student Member, IEEE,Gianluca Reali, Associate Member, IEEE, and Sven Zeisberg, Member, IEEE IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 20, NO. 9, DECEMBER 2002 Pages 1745-1753
Outline • WHYLESS.COM • Open Mobile Access Network (OMAN) • Requirements for PHY • UWB as PHY • UWB Domain Parameters • Current work
WHYLESS.COM • Cofunded by European Union • Current paradigmatic chain • Infrastructure – Service – Terminal (user) • Rigid: prevent a quick response to changing user needs and business models • Open Mobile Access Network (OMAN) paradigm • Efficient information transport • Modern, small scale, electronic business, evolutionary growth • Decouples user, info transport resources, content provision service • Goal: ‘standardize’ a new commodity dealing with the transportation of electronic information
OMAN Concepts • Administratively independent IP domains • external characterization of traffic in terms of QoS parameters • Virtual delay (d) • Network commodity • Standard measure of the level of the service • Differentiated Services (DiffServ) compliant approach to guarantee QoS (RFC 2475) • Usage-based pricing • Actually used and/or reserved network resources • QoS charge beyond the flat access charge
Entities involved • End Users • Consumers needing service • Network Service Providers (NSPs) • Provide the network infrastructure • Network Resource Manager (NRM) • Manage the domains owned by the NSP • Guarantee a set of edge-to-edge services over domain • Application Service Providers (ASPs) • Application service and IP connectivity to End User • Information Brokers (IBs) • End User and ASP mediator • Identifies ASPs and provides ASPs history • Resource Brokers (RBs) • ASP and NSP mediators
End to End Service Provisioning Procedure End user (through IB) Identifies an ASP for a specific service Requests service (quality of desired service and willingness to pay)
End to End Service Provisioning Procedure ASP Transforms customer’s qualitative requirements into quantitative technical parameters Requests RB to find the “best” path to deliver the application service (eBDL)
End to End Service Provisioning Procedure RB Identifies the potential domains and checks their offers with e-Table Runs an interdomain routing algorithm
e-Table • f(d) : Technical cost of information transfer in commodity unit • f(∞) = 0 • α : Cost of each commodity unit • Network parameters, end points, domain policies • γ : Price variation factor • Market fluctuations • Bres,i = xiPs (0<xi<1)
End to End Service Provisioning Procedure RB -> ASP Path found Teriffs charged
End to End Service Provisioning Procedure ASP -> End user : Relevant price End user -> ASP : Accept/Reject ASP -> Each NAP involved : Service contract
PHY Requirements • Advanced and scalable radio transmission technology • Heterogeneous traffic with specific QoS • PHY should not be a bottleneck • Short-term trading of wireless and wired information transport resources • Wireless: Ownership not clear • On demand spectral usage shared with others • Synchronization probs (TDMA) • Combine resources with single radio front end (FDMA)
PHY Layer for OMAN • PHY layer requirements: • Single PHY channel has to support a wide range of net data rates • Re-configurable on-the-fly, to maintain QoS • Support continuous and packet-oriented channels • Mobility of terminals has to be considered. • PHY layer functionality • Coding according to the appropriate FEC scheme • Pulse modulation by the appropriate mapping of the encoded bits onto symbols • Insert/remove pilot symbols/preamble to/from the symbol train • Perform radio transmission and reception including synchronization
UWB Characteristics • Large data rates over short distances without allocating dedicated spectral resources • Software controllable parameters • Adapt bit rate according to terminal location, propagation condition and service requirements • Enables highly resilient, scalable and flexible networks • Other features • Low mean transmission power • Through the wall penetration • Precision location • Minimized hardware complexity
UWB for OMAN • Unsynchronized UWB • Fulfills wide range of requirements • End user service contracts • Dynamic domain requirements from NRM • Broad range of data rates • Classes of services • No sophisticated cell planning • Same frequency • On the fly modification of transmission parameters • Processing gain, TH sequence, duty cycle, temporal pulse shape, code rate
IR-UWB • Spread Spectrum technology with BW in GHz • Impulse Radio • Best studied • Relatively simple implementation • Large crest factor but with low average power • Whole band to every service provider • Improved spectral efficiency • Wider range of rates possible • Same equipments for all providers • Disadvantages: • Synchronization not possible • Power monitoring for billing • Less affected by fading
PHY design considerations • IR with FCC regulations • Centralized wireless network • Up- and down-link have the same air interface definition • Only continuous pulse transmission with hard handovers are currently considered
UWB Domain: Per Domain Behavior • NRM functions • Admission control able to support mobility • Provide bandwidth estimation LMG: Local Mobility Gateway
UWB Domain: Admission Control Function • Guage&Gate Reservation with Independent Probing (GRIP) • Verifies RB claims before NRM stipulates contract • Handoffs
UWB Domain: Bandwidth Estimation • Discovery probe packets • Tradeoff: Overhead v/s Information accuracy • Per Domain Behavior (PDB) table
UWB Transmitter • Design parameters • Cannot be changed once the project is finalized • w(t), Tm, Tc, Na, cn,k, dn,k, Np, B • Control parameters • Can be varied by MAC • Em, Ns, Nh, Nd • Derived parameters • Values dependent on Control parameters • Tf, Ps, Nc, Ts, M, K, Rs, Rb, Es, Eb
Current Work • Performance degradation of UWB systems can be analytically predicted • UWB DS-IR more robust against existing radio technologies • Controlled licensed mode for higher transmission power • Spectral shaping to avoid interference • TH codes investigated • Spectrogram based technique + threshold detector • Turbo encoding was found to improve performance
References • www.whyless.org • Deliverable D5_2b, “Transceiver architecture and algorithms”, Jan 2003 • Deliverable D5_3b, “Physical layer architecture and performance”, Jan 2003 • Deliverable D5_4b, “Ultra-Broadband coexistence (final)”, Dec 2003