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FirstNet Session 5A April 15, 2014 Speakers: Brandon Abley, Statewide Interoperability Program Manager Brandon.abley@state.mn.us Mark Navolio, Televate LLC Project Manager MnFCP FirstNet Consultation Project. Agenda. Quick Introductions Act establishing FirstNet
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FirstNet Session 5A April 15, 2014 Speakers: Brandon Abley, Statewide Interoperability Program Manager Brandon.abley@state.mn.us Mark Navolio, Televate LLCProject Manager MnFCP FirstNet Consultation Project
Agenda • Quick Introductions • Act establishing FirstNet • FirstNet Organization & Duties • State Duties • Minnesota/FirstNet Consultation (MnFCP) • Stakeholder Responsibilities.
About ECN Emergency Communication Networks is a division of the Minnesota Department of Public Safety • The statewide 9-1-1 program • Allied Radio Matrix for Emergency Response (ARMER) • Communications Interoperability • Statewide Emergency Communications Board standards and projects • Minnesota/FirstNet Consultation • Our Expertise • Broadband Networks (700 MHz, 4.9 GHz, LTE, Wi-Max, Wi-Fi, Microwave, Fiber) • Land Mobile Radio (P25 Voice & Data, Narrowbanding, RF Testing) • Network Planning and Project Management • Business Modeling and Development • Interoperable Communications • Strategy and Planning
About Televate Company Overview Founded in 2001, Televate is a leading engineering consultancy delivering innovative communications and IT services and solutions for public safety and critical infrastructure industries. Our technology and program management experts design sustainable, interoperable land mobile radio, wireless broadband networks and applications, and advanced information technology solutions. • Our Expertise • Broadband Networks (700 MHz, 4.9 GHz, LTE, Wi-Max, Wi-Fi, Microwave, Fiber) • Land Mobile Radio (P25 Voice & Data, Narrowbanding, RF Testing) • Network Planning and Project Management • Business Modeling and Development • Interoperable Communications • Strategy and Planning
Creation of FirstNet • Middle Class Tax Relief and Job Creation Act of 2012, passed Congress on February 17, 2012, establishes: • “FirstNet” First Responder Network Authority, build & operate • “NPSBN” Nationwide Public Safety Broadband Network • Requires FCC to allocate the D Block spectrum to public safety; D Block, 10 MHz; for a total of 20 MHz • The FCC tasked with Technical Advisory Board for define requirement for interoperability • Develop minimum technical requirements • Ensure nationwide standards for use and access to the network • FirstNet is the sole authority to build, operate & maintain the NPSBN • Issue open, transparent, and competitive request for proposals (RFP) to private sector entities
Why FirstNet? • Carrier networks are often overwhelmed with commercial traffic during emergency events • For obvious reasons public safety does not want to preempt this communication
FirstNet Advantages • LMR does a great job of providing mission critical voice, however… • Public safety agencies have been relying more and more on wireless data services (Verizon, AT&T, etc.), but there have been problems: • Lack of Availability: commercial network tend to become busiest during emergency events • Lack of Reliability: most commercial networks are not built with the level of redundancy as public safety • Lack of Coverage: commercial networks prioritize populated areas first; whereas public safety strives for ubiquitous coverage • Benefits • Better Price & Choice: adopting a commercial standard (LTE) provides a much greater marketplace (2 billion vs. 25 million public safety worldwide) • Keeps Pace with Technology; with a great emphasis on backward compatibility
Dedicated Frequencies • Dedicated Frequencies: the FirstNet NPSBN will utilize dedicated frequency channels, Band Class 14. • Two (2) paired 700MHz channels of 10MHz each for total of 20 MHz • Do not compete with commercial users during emergencies
LTE Overview EPC RAN UE UE UE
PSBN Reference Model • Source: NPSTC: Public Safety Broadband High-Level Statement of Requirements for FirstNet Consideration
PSBN Reference Model • Source: NPSTC: Public Safety Broadband High-Level Statement of Requirements for FirstNet Consideration
Standards Timeline • May 2010: FCC requires all 700MHz waiver recipients to use LTE release 8. Objective is to ensure consistency and interoperability in the Public Safety Community • May 2012: FirstNet Technical Advisory Board requires release 9 • LTE Advanced (Release 10) was approved as a 4G technology by ITU • Release 12 will provide Public Safety Enhancements (Proximity Based Services, Group communications, High Power User Equipment). • Planned for Q2 2014, Commercially available by Q2 2015
LTE Air Interface Basics • Uses Orthogonal Frequency Division Multiple Access (OFDMA for downlink) and SC-Frequency Division Multiple Access (FDMA for uplink) • Resource Block (RB) = 180 kHz for 0.5 milliseconds • Each RB delivers capacity • Speed per resource blocks depends on signal conditions • Higher signal to noise ratio uses more bits per second • LTE scheduler allocates different RB depending on user needs, radio conditions, priority
LMR = site separation Frequency Reuse • LTE = frequencies reused at all sites F1 F1 F1 F3 F1 F2 F1 F1 • Sites reuse and are not separated • Full spectrum capacity usable at each site • Inter-site interference degrades performance between sites • Sites reuse frequencies but are separated so that interference is not harmful • Capacity is reduced by partial spectrum use
Total 10 MHz in each direction Estimated >3x more spectral efficiency than 3G Varies based on antenna configuration 2x2 MIMO 4x4 MIMO Highly variable based on signal-to-noise ratio Quality of Service (QoS) provides dynamic application type, user and throughput management capabilities LTE Performance Considerations
Air Interface Details • The maximum bit rate greatly depends on the modulation scheme, antenna transmission scheme (MIMO), and number of RB’s allocated (PSBN will have 50 RB). • Adaptive Modulation and Coding in Uplink and Downlink: QPSK, 16QAM, 64QAM. • Orthogonal Frequency Division Multiple Access (OFDMA) • Multiple users transmit data at the same time over the same bandwidth with relatively minimal interference
Modulation & Coding Schemes • LTE changes the modulation and coding scheme (MCS) based on the channel quality • The better the signal quality, the higher the throughput • Only the modulation and coding scheme with the best throughput is selected. • QPSK: 2 bits/symbol • 16 QAM 4 bits/symbol • 64 QAM (Optional Uplink) 6 bits/symbol 8 MB; High # of RBs; 64QAM 2 MB; Med # of RBs; 16QAM 0.8 MB; low # of RBs; QPSK
Data Multiplexing • MIMO (Multiple Input Multiple Output) • Spatial data multiplexing of several data streams • Uses 2 or more antennas to transmit and receive over air interface. This increases throughput. Potential Peak Rates (Single user consuming all radio resources and close to site)
LTE Performance Considerations • Other performance enhancing techniques • Frequency Selective Scheduling • Improves spectral efficiency and cell edge throughput • Scheduler uses CQI values sent by UEs and their throughputs to set the priority of every resource of every UE • Best resources, based on average channel quality, are selected for UE use • Fractional Frequency Reuse (FFR) • Similar to old systems with frequency planning • Small portion of sector resources are either never used by eNodeB or are used with reduced power • Provides performance increase for users at cell edge
Interference vs. Speed • Users close to sites have high signal compared to noise • Users between sites or with poor coverage have low signal to noise • LTE automatically chooses speeds based on signal quality • Design impacts coverage and capacity • More capacity possible with cell splitting
Assess Development • Redevelopment: • 62% of the sites will utilize existing structures • 38% New towers, monopoles or rooftop towers • Backhaul: • 46% of the sites have sufficient backhaul • Half the sites will need new microwave • 7 sites will require leased connectivity • Generators: • more than 80% of the sites will require new generators • Supplemental Sites • 15 additional sites are budgeted as supplemental sites
Device Economies of Scale • Many cell phones are made to support global frequencies and global technologies • One billion annual cell phone sales vs. < 17 million US government workers total • Even as BC 14 chipsets become available, handset vendors may not be willing to support them due to low quantities • The BC 14 market may not be large enough to support iPhones, iPads, Blackberries, etc. by itself • If public safety cannot leverage commercial economies, device choices will be limited
Assess Carriers • Priority / Pre-emption • Carriers unwilling to provide special government priority access or preemption of non-public safety users on their networks • Continued commercial data growth is expected to pose increased risks of network congestion* (*AT&T data growth 8,000% 2007-2010) • Coverage • Little commercial benefit to meet similar to LMR county-by-county coverage requirements • Handover between Commercial and FirstNet • Unclear whether carriers will support seamless two-way handovers between public-private networks • Network Availability • Carrier networks estimated at 99.5% available. Limited redundant backhaul. • Potential Device Issues • Two band (not three) 700 MHz expected
System Architecture Evolution • In the SAE is the Evolved Packet Core (EPC), which consists of only 2 node types now referred to as Evolved Packet System (EPS) • eNodeB (eNB) in the user plane • The eNB comprises all radio access functions from the node B and radio network controller (RNC). Connected to each other via X2 interface. • MME (Mobility Management Entity) in the control plane • In control plane connected to EPS gateway which has two parts, SGW and PDN gateway • The SGW, PGW and MME can be integrated into the same box or the MME can be integrated into the eNB
Radio Access Network (RAN) • The evolved RAN for LTE is compressed into a single node; the eNodeB • The eNB hosts the PHYsical (PHY), Medium Access Control (MAC), Radio Link Control (RLC), and Packet Data Control Protocol (PDCP) layers that include the functionality of user-plane header-compression and encryption • It performs many functions including radio resource management, admission control, scheduling, enforcement of negotiated UL QoS, cell information broadcast, ciphering/deciphering of user and control plane data, and compression/decompression of DL/UL user plane packet headers.
Mobile Management Entity (MME) • The Mobility Management Entity (MME) is the key control-node for the LTE access- network. • It is responsible for idle mode UE tracking and paging procedure including retransmissions. • The MME also provides the control plane function for mobility between LTE and 2G/3G access networks.
Serving Gateway (SGW) • The Serving Gateway (SGW) • routes and forwards user data packets • acts as the mobility anchor for the user during inter-eNB handovers and • anchor for mobility between LTE and other 3GPP technologies • Manages and stores UE contexts, e.g. parameters of the IP bearer service, network internal routing information
PDN GW – Packet Data Network Gateway (P-GW) • The Packet Data Network Gateway (P-GW) • Provides connectivity to the UE to external packet data networks by being the point of exit and entry of traffic for the UE. • Assigns IP addresses • Acts as the anchor for mobility between 3GPP and non-3GPP technologies such as 2G, 3G, WiMAX and 3GPP2 (CDMA 1X and EvDO).
PCRF & HSS • The Policy and Charging Rules Functions (PCRF) entity performs the following functions: • Ensures traffic mapping and treatment is in accordance with the user's subscription profile. • Derives the QoS level and the associated Guaranteed Bit Rate (GBR) and Maximum Bit Rate (MBR) limits for the session. • Derives the priority based on prioritization policy. • Home Subscriber Server (HSS) • Contains user subscription data
Quality Of Service • A bearer is an aggregate of one or more IP flows related to one or more services. • Each bearer is assigned a QoS Class Identifier (QCI) that decides how the data is treated. QCI is a scalar value mapped to specific bearer level packet forwarding treatment. • Guaranteed bit rate • Priority • Packet delay budget • Packet Error Loss Rate allowed • Bearer extends from UE to PGW • Quality of Service of bearer assigned based on subscription • All service data flows within a bearer receive same level of QoS • Dedicated bearers established when specific treatment of data is required • They can be Guaranteed Bit Rate (GBR) or non-GBR • Non-GBR bearers belonging to the same UE share an Aggregate Maximum Bit Rate (AMBR).
Lesson 1: Coverage Is Not Equal LMR Coverage • LMR link budget is better than LTE at broadband speeds • 4G requires far more sites to match coverage • E.G. Washington, DC – 12 broadband sites to cover 90% outdoors versus 10 LMR sites to cover 95% indoors • However, LTE could scale to non-broadband speeds 4G Coverage
Lesson 2: Not all LMR sites may be Ideal for LTE • Throughput drops as signal to noise ratio drops • Degraded service at cell borders – highly variable throughput over coverage area • Overlapping service means lower signal to noise ratio • LTE is not well suited for LMR “boomers” • But may be able to go lower on a tower • High overlap on LMR design will cause interference Large overlap area with poor SNR
Lessons 3: Bandwidth Control is Critical • Overloading By A Few Users • Inauguration Day 2005 • Inefficient video codecs from only six users! • Instituted rate caps to manage bandwidth • Poor Service Quality • Streaming content almost unusable • Other content delayed • LMR traffic variation is high, but broadband will likely be higher due to video • Designing networks for 95th percentile traffic is critical Example of Pixilated Video
Lessons 4: Application Interoperability Is Key! • LTE = ½ of the problem! • Without interoperable applications, packets delivered but not understandable • For Data, the network and the application must be interoperable • Wherever the users are on the Internet • Securely and with quality of service • Independent of who serves the application • E.G., Video: • Multiple different video solutions from different vendors • Using “standard” codecs • Gateway style solution is extremely expensive • There are many video codecs and tradeoffs for public safety to consider Core B Core A eNB B eNB A 你好 ? MPEG4 versus MJPG Video