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Lte for public safety networks (get further insights at: http://trends-in-telecoms.blogspot.com)
Lte for public safety networks (get further insights at: http://trends-in-telecoms.blogspot.com)
Lte for public safety networks (get further insights at: http://trends-in-telecoms.blogspot.com)
Lte for public safety networks (get further insights at: http://trends-in-telecoms.blogspot.com)
Lte for public safety networks (get further insights at: http://trends-in-telecoms.blogspot.com)
Lte for public safety networks (get further insights at: http://trends-in-telecoms.blogspot.com)
Lte for public safety networks (get further insights at: http://trends-in-telecoms.blogspot.com)
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Lte for public safety networks (get further insights at: http://trends-in-telecoms.blogspot.com)

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  • 1. C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND® LTE TECHNOLOGY UPDATE: PART 2 LTE f Public Safety Networks for bl f k Tewfik Doumi, Mike F Dolan, Said Tatesh, and Alessio Casati, Alcatel-Lucent f George Tsirtsis, Kiran Anchan, and Dino Flore, Qualcomm ABSTRACT This is not a phenomenon unique to North America. On 11 June 2012 the TETRA & Criti- It is increasingly being recognized that effec- cal Communications Association (TCCA) and tive communications are key to a successful the National Public Safety Telecommunications response to emergency and disaster situations. Council (NPSTC) announced that they had The ability of the first responder emergency ser- signed a Memorandum of Agreement (MoA) to vices to communicate among themselves and to underscore their joint commitment to the need share multimedia information directly affects the to develop mission-critical public safety commu- ability to save lives. This is reflected in increas- nications standards for LTE-based technology ing public investment in broadband public safety y [2]. communication systems. These systems have Public safety first responders’ essential mis- some specific requirements, which are outlined sion is to protect citizens and property and to in this article. As LTE is expected to become the save lives. The technologies used to convey criti- most widely deployed broadband communication cal public safety information must be present, technology, we examine the capability of LTE to efficient, and reliable. Public safety communica- meet these requirements, and identify possible tions network managers are charged with the future developments to LTE that could further ultimate responsibility of ensuring the survivabil- enhance its ability to provide the necessary ser- ity of their networks, and they have sometimes vice. had to work within severe constraints to accom- plish their mission. Various issues, especially y INTRODUCTION lack of funds and useful spectrum, have led to situations that have not permitted technology y In recent years the public safety community, upgrades for many years. Meanwhile, technolo- more particularly first responders, has watched gies used in commercial networks have gone with envy the growing wireless multimedia capa- through three generations in the same time bilities offered to consumers by new 3G tech- span. One of the goals of the U.S. push for com- nologies. Although some first responders make mercial technologies was precisely to allow for use of WiFi in the interference-prone unlicensed alignment with the capabilities of commercial spectrum, the majority of first responders linger networks in addition to achieving communica- in a 2G world. Global attempts at garnering sup- tions interoperability between agencies. The end port for additional spectrum or reshuffling exist- result should be a lowering of both capital and ing spectrum, the keys to broadband deployment operational expenditures. have not always been successful because of hin- Public safety networks are seen as mission- drances such as commercial stakeholders’ inter- critical; that is, reliable, resilient, and secure, ests and budget constraints. However, nowhere while meeting other stringent functionality y was the effort to enhance public safety commu- requirements in terms of service accessibility, nications as sustained as in the United States radio coverage, end-to-end performance, and post 9/11. device characteristics. These critical operational Today, 20 MHz of dedicated spectrum in the needs remain the principal drivers for technolo- 700 MHz band and some initial funding to build gy features and the design and engineering of f a nationwide Long Term Evolution (LTE) net- the “public safety grade” network. In addition, work intended primarily for emergency services public safety is accustomed to niche applications are available [1]. More funds are planned to be and functionalities such as automatic vehicle made available after the auction of TV broad- location, (fast) push-to-talk, dispatch services, cast spectrum. This achievement would not have priority and group communications, and off-net- been possible without the cooperation of regula- work peer-to-peer communications (also known tors, legislators, manufacturers, and the public as “direct-mode” or “talk-around”), group call, safety community. North of the U.S. border, group management, ciphering, over-the-air- 1 Note that while P25 Canadian public safety agencies are on the same rekeying, supplementary services, non-trunked Phase 1 offers both non- path with spectrum harmonization and potential- modes (which include talk-around and repeater trunked (conventional) ly an LTE mandate. Elsewhere, attempts at mode), 1 dual-scan or dual-watch, and many y and trunked modes, clearing up new spectrum bands, leveraging other features and functionalities that distinguish TETRA does not offer a commercial services, or reusing existing spec- public safety services from typical consumer ser- non-trunked mode. trum assets are being considered. vices over commercial networks. Some of these 106 0163-6804/13/$25.00 © 2013 IEEE $ IEEE Communications Magazine • February 2013C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND®
  • 2. C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND® Network management RAN Backhaul system Subscriber Terminal Network management management management Network monitoring UE eNodeB console Agencies’ Local LANs transport IP backbone Aggregation Subscriber route e er management console UE EPC Internet, eNodeB databases, servers, etc. S/PGW MME HSS PCRF Broadcast IMS SMS Location center center server Applications* PTT GW/server Core *Some may be local Figure 1. Sample public safety LTE network architecture. aspects are discussed in detail later. As public 2-slot time-division multiple access (TDMA) for safety embraces broadband technologies such as the more recent Phase 2 specifications. The lat- LTE, there is a desire to replicate all existing ter allows for higher spectral efficiency with 1 and applicable features and port all applications voice channe/6.25 kHz, which is equivalent to onto that broadband platform, while maintaining the 4-slot 25 kHz TETRA channel structure. interoperability with existing narrowband net- Although P25 addressed essential public safety y works. requirements, TETRA targeted both public safe- Figure 1 provides a view of the architecture ty and non-public safety professional users with of a public safety LTE network. similar critical needs, e.g., utilities and trans- This article addresses the transition to broad- portation, leading to a greater proliferation of f band technologies for public safety in light of TETRA networks than P25 networks across the existing standard LTE specifications. Some globe. TETRAPOL, no relation to TETRA, is needed enhancements for a full replacement of another (proprietary) 12.5 kHz FDMA technolo- narrowband technologies are identified. gy commercially deployed in some countries. Originally intended for the provision of voice and low-speed (~9.6 kb/s) data services, both BACKGROUND ON TETRA and P25 saw the development of so- called wideband technologies for the provision EXISTING PUBLIC SAFETY SYSTEMS of higher-speed services, with rates of close to 80 In their evolution from analog to digital systems, kb/s in a 50 kHz wide channel. TETRA release public safety technologies have followed two 2, or TETRA Enhanced Data Services (TEDS), major distinct paths: Project 25 (P25) and Ter- was developed to be backward compatible with restrial Trunked Radio (TETRA). Project 25 TETRA so as to provide both voice and data, was essentially pursued under the auspices of the whereas Selective Adaptive Modulation (SAM) U.S. Telecommunications Industry Association was to be used as a supplementary technology to (TIA) and TETRA under the European P25 for data services only (e.g., [4, 5]). Obstacles Telecommunications Standards Institute (ETSI). to the deployment of TEDS have included lack k More recently, the ETSI 2-slot 12.5 kHz digi- of spectrum, whereas SAM’s deployment was tal mobile radio (DMR) is aimed at markets overtaken by regulatory changes, such as the such as utilities, transportation, business, and the rechannelization of the 700 MHz public safety y industrial sector. The reader can refer to [3] for spectrum and adoption of LTE in the United an inventory of land mobile radio (LMR) sys- States, which has led in some cases to the use of f tems. Project 25 comes in two flavors: frequency- proprietary wideband protocols such as High division multiple access (FDMA)for the more Performance Data (HPD), which combines mul- common 12.5 kHz Phase 1 specifications, and a tiple narrowband channels. Moreover, the recent IEEE Communications Magazine • February 2013 107C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND®
  • 3. C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND® support by the TETRA Critical Communications Communication bearers, especially speech Communication to A ssociation (TCCA) of LTE as the broadband bearers, transported across the LTE system technology of choice highlights challenges faced require varying priorities and have varying char- group members is by wideband standards such as TEDS [6]. acteristics. For example, a regular segment of f not confined to At the operational level, capabilities offered group call speech (a talk spurt) will require the speech, as data mes- by technologies such as TETRA and P25 reflect same characteristics as a segment of emergency y actual needs of public safety since the respective group call speech, but the latter will need higher saging can also be protocols were developed with end users’ needs priority to guarantee that it is not delayed by reg- sent in parallel to as requirements. ular daily activities. In the same way, the bearer characteristics for speech are different than those speech. Data mes- for real-time video or a background short text saging may involve FEATURES AND REQUIREMENTS OF message. The LTE network must be able to sup- port all of these in a dynamic environment. any amount of data, PUBLIC SAFETY NETWORKS To accomplish the management of such large or small, text, A public safety communications system provides diverse and dynamic bearer traffic, LTE provides video, image, and so the means for first responders to accomplish quality of service (QoS) controls referred to as their mission by communicating in a variety of QoS class identity (QCI) and access retention pri- on, and may be sent media, foremost of which is speech. Individuals ority (ARP). An application, such as a push-to- from a group in a fire brigade or a police department are typi- talk (PTT) server, can use standardized interfaces, member who is not cally organized into groups of individuals with such as the Rx interface from applications like different responsibilities. Some groups may have voice or video applications, acting as an applica- currently speaking. geographic areas to cover, and other groups may tion function to the policy and charging rules be organized based on types of skills or activities function (PCRF), to exert authorized control over to be performed. Within and across those groups the bearers that carry communications between will be found some individuals with supervisory itself and the first responder’s user equipment or dispatch authority and responsibility. These (UE). These QoS controls provide the ability to supervisors and dispatchers manage and coordi- manage the use of the broadband system to nate the efforts of the first responders. accomplish the mission of first responders. A group call involves the communication of Currently, LTE standards support QoS con- speech to all members of the group. The permis- trols for unicast bearers — bearers that reach sion to speak is controlled by a dispatcher assist- only a single UE device. A broadcast capability ed by automated methods. Some individuals may called evolved multimedia broadcast and multi- be able to receive multiple group calls simulta- cast service (eMBMS) also exists in LTE and neously, using their device to listen to the one will be required to provide communications to with the highest priority as signaled by the sys- large numbers of first responders in a close geo- tem. A first responder may indicate an emergen- graphic region. The QoS controls for eMBMS cy situation, causing all of their subsequent are yet to be finalized and will need to parallel communications to the group to be treated as an to a great extent the capabilities provided by the emergency group call. An emergency alert can Rx interface. also be signaled by a first responder to a defined LTE network must support diverse traffic in a set of individuals, typically including dispatchers, robust environment due to the critical nature of f supervisors, and other specific group members. much of the first responders’ communications. Communication to group members is not Some of this robustness is provided in standard- confined to speech, as data messaging can also ization; other aspects result from careful net- be sent in parallel to speech. Data messaging work planning. For example, handover of a may involve any amount of data, large or small, device from one LTE cell to another is a stan- text, video, image, and so on, and may be sent dardized mechanism; cell location and capacity y from a group member who is not currently planning are required to make sure that another speaking. cell with sufficient resources is available for such Dispatchers have the responsibility to coordi- a handover. nate the efforts of the first responders. This can Robustness goes beyond just cell and capacity y involve merging groups into a single temporary planning, however. It demands that alternative group to handle situations that require the paths be available in the event of congestion and efforts of multiple disciplines and increased resource outages. If a link from one piece of f numbers of responders. Dispatchers and supervi- equipment is broken or cannot contact another, sors have the ability to override the current an alternative link is needed to avoid a break in speaker when needed. communications. Standards provide the ability to Most important, many public safety communi- go to an alternative device. Network planning is cations have a mission-critical aspect that places required to ensure that the alternate link and special requirements on the underlying radio tech- alternate equipment are in place when needed. nologies. When a first responder pushes the but- When part of a public safety network fails, ton on their device to request to speak, they need the remainder of the network must continue to the confidence that they will be successful with provide services to the greatest extent possible. extremely high probability. In an emergency situa- Group calls will need to continue in spite of loss tion when congestion may exist, the emergency of contact with some or all of the core network k group call must go through or lives may be lost. components. One of the members of the group These features place high demands on the under- may be authorized to assume command respon- lying radio system. In a broadband system, such as sibilities and act as a dispatcher or supervisor. LTE, those demands are magnified by the amount The LTE transport infrastructure, to the greatest and diverse types of communication occurring. extent possible, must support such continued 108 IEEE Communications Magazine • February 2013C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND®
  • 4. C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND® communications. The work to accomplish this w ill likely involve both application-level and LTE network-level enhancements. It may incor- porate what is known as direct mode. Direct mode is the ability of two or more pub- Dispatcher PTT server lic safety devices to communicate directly without the use of network infrastructure. This direct link would be used to connect two or more individuals when out of range of the network cells, for exam- T s Transport network n wor ple, while fighting a fire in a remote part of a for- est, or when the cellular infrastructure is damaged in disaster areas. This is similar to two computers communicating in a peer-to-peer manner using IEEE 802.11 radio technology. Much work is underway in the Third Generation Partnership Project (3GPP) standards body to define the requirements for such direct mode communica- Speaker Group Group Group Group Group tions in LTE, and to develop solutions to support member member member member member multiparty direct mode communications. Figure 2. An example of group communications in a public safety network. USING LTE FOR Prioritized access to public safety services is PUBLIC SAFETY NETWORKS generally understood to be supported by LTE. LTE is being widely deployed as the global This includes: mobile broadband standard. Perhaps the main • Prioritized handling of emergency calls and benefit in the use of LTE for public safety is multimedia priority services in the network having large-scale deployment of LTE and a and over the air large ecosystem, which allow less expensive • Mechanisms for access and congestion con- equipment based on unified standards. These trol in the network and over the air standards can be adopted by all public safety • An end-to-end QoS framework (and the agencies and organizations globally, thus sharing ability of network schedulers to prioritize scale with non-public-safety applications of LTE. among traffic flows with different QoS LTE offers a simple all-IP system architec- characteristics) ture and flexible air interface with low latency • Broadcast of alert/warning messages and enhanced performance and efficiency, sup- Interoperability, or the capability of commu- porting flexible carrier bandwidths from below 5 nicating anytime and anywhere across the net- MHz up to 20 MHz. Many frequency bands work, constitutes the principal motivation for (paired and unpaired) in different regions have technology evolution toward a common stan- so far been specified by 3GPP for LTE, allowing dard. While interoperability can be addressed at a wide range of ecosystem support and regional different levels [7], the capability for networks flexibility for operators. from different vendors to interwork or the ability y Furthermore, the LTE system offers great for visiting users to access services is key to flexibility to support a wide variety of deploy- improving mutual operations and providing ment scenarios and operators’ needs, including: effective responses during major incidents. In its • Homogeneous and heterogeneous networks: enactment of the new legislation, which, among macro, pico, and femtocells other topics, mandated the use of LTE and allo- • Single-carrier and multicarrier (including cated an additional 10 MHz for the purpose of f cross-carrier scheduling) public safety broadband services, the U.S. • Support for both frequency-division duplex Congress required that the development of mini- (FDD) and time-division duplex (TDD) mum interoperability requirements be the first • Intercell coordination in time and frequency step [1]. The report delivered by the Interoper- domains ability Board, comprising members of industry, • Single and multipoint transmission and service providers, and the public safety commu- reception nity, all appointed by the Federal Communica- • Interworking and mobility with other radio tions Commission (FCC), delves into such access technologies such as code-division critical interoperability aspects as network inter- multiple access (CDMA) and wireless lAN faces, security, applications, devices, testing, han- (WLAN) dovers, roaming, design, and prioritization [8]. • Range of UE categories and capabilities • Unicast and broadcast service support Therefore, LTE is well positioned to meet LTE ENHANCEMENTS FOR the requirements for the evolution of public safety systems. PUBLIC SAFETY 3GPP has begun work on proximity services Two critical features deemed essential for the (ProSe); one of its objectives is to satisfy the support of public safety mission-critical service public safety requirement for direct mode or talk are currently missing in LTE. These features around. Other requirements being investigated are: relative to LTE capabilities include communica- • Direct communications tion with helicopters and low-flying aircraft. • Group communications IEEE Communications Magazine • February 2013 109C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND®
  • 5. C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND® Recognizing that a group call for public safe- 758 768 788 798 ty can be characterized by a multitude of users that receive a common downlink communication stream, a bearer resource scheme, unlike the North America separate per-user bidirectional bearer, is being 380 470 380 803 considered to optimize overall resource usage. To this effect, discussions on efficient broadcast and multicast schemes are underway in 3GPP. Central and Latin America Potential system architecture enhancements 380 470 380 803 805 865 are also being considered to allow effective con- trol of the group call bearers via a non-3GPP application function, which could be operated by y Asia-Pacific a public safety agency. To ensure that a critical group communication has precedence for 380 470 698 790 862 resource allocation and resource usage over non- priority traffic, bearer retention schemes are being considered for group calls. To extend the Europe mobility aspects to group calls, requirements pertaining to bearer management for service Potential band for dedicated blocks continuity are also being discussed. Band under study for dedicated blocks On the other hand, ongoing work in various Through commercial providers public safety fora (e.g., TIA TR-8.8 and TETRA) Already assigned has identified several interfaces within the LTE network that are of particular interest. Foremost Figure 3. Sub-1GHz spectrum bands of interest for broadband public safety. u is the Rx interface, which allows, for instance, a PTT service application to manage the QoS for PTT group members relative to unicast bearers. A study in 3GPP has considered direct com- As the priority of a group call varies, depending munications [9], and a Work Item is working to on the relative importance of the communication specify group communication enablers for LTE to the importance of other group calls, the PTT [9]. Both these activities are targeting feature service application will need to be able to reach availability in Release 12. These features are dis- into the LTE network and manage the QoS of f cussed in more detail in the following subsec- the applicable unicast bearers. So far, it appears tions. that the existing functions of the Rx interface Other features are also expected relating to will suffice. radio aspects, including resilience in the face of The LTE network includes a broadcast capa- events causing the link of the radio access to the bility, eMBMS, which will be critical to public core to be interrupted. Further requirements safety. For example, a generalized interface that may emerge as operational experience is gained: will allow the PTT service application to manage support of public safety is expected to become a the broadcast bearers is not fully defined at this long standing effort in 3GPP from both the point. This interface would exist between the innovation and maintenance standpoints. PTT service application and the broadcast multi- cast service center (BM-SC). It is expected that DIRECT COMMUNICATIONS OVER LTE many of the functions provided by this interface Over the past year 3GPP has been working to would be analogous to the QoS controls provid- define use cases and requirements for what is ed by the Rx interface, but relative to broadcast generally called proximity services (ProSe). Prox- bearers instead of unicast bearers. imity services include device-to-device discovery and communication. Public safety requirements have specifically been considered as part of the PUBLIC SAFETY SPECTRUM study, so all proximity service requirements apply The current spectrum bands used by emergency y both in and out of network coverage (including services across the world cater for narrowband w hen the network is unavailable). In addition, services with channel bandwidths ranging from device-to-device communication includes one-to- 12.5 to 50 kHz. Both fragmented and contiguous one, one-to-many/unicast, one-to-many/broad- bands are common with bands sometimes inter- cast, and one-hop relay functionalities, as well as leaved with other services. Since the spectrum sit- considerations for access priorities and session uation does not lend itself to an easy technology y transfer between direct-based and network-based migration through, for instance, rechannelization communication paths. 3GPP have agreed to start of the active (narrowband) spectrum, the adop- specification work for the use cases and require- tion of broadband technologies such as LTE war- ments defined in the study. rants the allocation of dedicated spectrum bands. To be of practical use in a wide-area deployment, GROUP COMMUNICATIONS OVER LTE bands lying in the more congested sub-1 GHz 3GPP has also been working on enablers for spectrum are preferred. Bands around 5 GHz group communications for public safety in LTE. have been made available, but their use is limited To meet public safety demands, requirements to localized deployments or backhaul links. The such as low-latency communication bearer setup, option whereby public safety leverages commer- priority access for group calls, and QoS for cial bands, via a subscription, instead of a dedicat- group call bearers are being considered within ed spectrum allocation, is also considered by y the Work Item. some national regulators. A commercial subscrip- 110 IEEE Communications Magazine • February 2013C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND®
  • 6. C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND® tion would be likely to entail compliance by com- as a need to reuse existing narrowband site loca- mercial operators with a certain set of public safe- tions leads to a situation where the UE transmit While the challenges ty requirements. power needs to be higher than the 23 dBm cur- From a global perspective as seen in Fig. 3, rently defined for LTE devices. It is therefore of f in finalizing the stan- some of the dedicated spectrum bands being importance to align link budgets of narrowband dardization of these considered include bands in the 400 MHz, 700 services, essentially voice at 9.6 kb/s, with broad- features should not MHz and 800/900 MHz regions. In the United band services, with a minimum video data rate States, where plans for broadband public safety of 256 kb/s, in suburban and rural areas. To be underestimated, are more mature than anywhere else, the dedi- address these deployment issues, a Work Item there is confidence cated 20 MHz spectrum band at 700 MHz was was proposed in 3GPP RAN4 [12] to standard- made possible through the digital TV migration ize a new UE class with a higher power level. that industry focus process, which opened new spectrum opportuni- With potentially disparate and unsynchronized and momentum exist ties for broadband services. However, that was networks using the same channel (e.g., state- for these to be suc- not the case in Europe, with the first digital divi- level deployments in the U.S. 700 MHz band), dend plan allocating the whole repurposed spec- there is an expectation of potential coordination cessfully introduced trum to commercial operators instead; there may or operations guidelines when the high-power in the near future, be new opportunities with the second digital div- device is in the overlap region of adjacent cells, idend with the clearance of some TV channels to mitigate interference to neighboring networks’ and thus enable LTE below 703 MHz. For those countries adopting eNBs, but also when within a cell to mitigate to be the next the APT (Asia Pacific Telecommunications) interference to services in adjacent bands (e.g., generation system plan the assignment of a pair of blocks to public for legacy deployments). Furthermore, while the safety use is possible but unlikely. For example, typical eNodeB transmit power level is around for Critical in the Caribbean and Latin America region a 45 dBm per antenna branch, the use of high- Communications. number of countries are expected to follow the power UE may require higher power levels at APT band plan (703–803 MHz) for their digital the sites to balance uplink and downlink. dividend planning. However, as in Europe, emer- gency services are likely to be assigned (broad- band) spectrum slots in the 400 and 800 MHz CONCLUSION bands (i.e., outside the digital dividend band In this article the introduction of novel capabili- plan), with the possible exception of Brazil, ties in the LTE system for public safety and criti- where the 700 MHz band is favored. cal communications has been discussed. LTE In terms of channel sizes, these will vary promises not only to provide an evolution path given specificities in each country. For example, toward broadband capabilities for existing and the utilization of the heavily congested 400 MHz new public safety networks, but also opens new spectrum may lead to the availability of only lim- business possibilities for operators of commer- ited bandwidth (e.g., up to 3 MHz), and the use cial LTE networks. While the challenges in final- of half- duplex FDD because of the small duplex izing the standardization of these features should gap between transmit and receive spectrum not be underestimated, there is confidence that blocks. Other regions may opt for symmetric industry focus and momentum exist for these to assignments (e.g., 2 ¥ 5 MHz or 2 ¥ 10 MHz), be successfully introduced in the near future, and others for asymmetric assignments [10, 11]. and thus enable LTE to be the next generation In some cases, there may be a compelling need system for critical communications. for commercial spectrum allocations in order to garner revenues from auctioning the spectrum. REFERENCES Such an approach could be supplemented by a [1] Middle Class Tax Relief and Job Creation Act of 2012, spectrum sharing requirement with prioritization Pub. L. No. 112-96, 126 Stat. 156 (2012) (“MCTRJC of public safety traffic. Act”). [2] TCCA and NPSTC: http://www.tandcca.com/about/arti- ____________________ In general, since those assignments are driven cle/17582. _____ b y the expected population of users and their [3] ITU-R M.2014-1 Report, “Digital Land Mobile Systems anticipated traffic profiles, which are a function for Dispatch Traffic,” 2006. of procedures in place or associated technology [4] TIA TSB-902.BAAA, “Wideband Air-Interface Overview,” May 2005. available (e.g., in-vehicle cameras), the size of [5] ETSI TR 102580, v1.1.1 “Designer’s Guide, TETRA High- spectrum bands will vary. Therefore, spectrum Speed Data; TEDS,” 10/2007 harmonization may not be achievable unless [6] TCCA Board’s Statement available at cooperation and collaboration occurs between http://www.tetramou.com/assoc/page/18100. [7] SAFECOM-Department of Homeland Security, “Interop- the emergency services of neighboring countries. erability Continuum,” available at ___________ http://www.safecom- The alignment of the public safety spectrum program.gov/SiteCollectionDocuments/Interoperability_ _____________________________ between Canada and the United States is a per- Continuum_Brochure_2.pdf. _______________ fect illustration of such broadband spectrum har- [8] Technical Advisory Board for First Responder Interoper- ability, “Recommended Minimum Technical Require- monization. ments to Ensure Nationwide Interoperability for the Nationwide Public Safety Broadband Network,” May 2012. UE TRANSMIT POWER [9] www.3gpp.org/ftp/Specs/. [10] Australian Communications and Media Authority, “The The extent of radio coverage for public safety 900 MHz Band — Exploring New Opportunities; Initial services is for the large part driven by geograph- Consultation on Future Arrangements for the 900 MHz ic considerations rather than population density; Band,” May 2011. the larger the country, the more extensive and [11] WIK-Consult, “PPDR Spectrum Harmonization in Ger- many, Europe and Globally,” Dec. 2010. costlier the deployment. Furthermore, a desire [12] Motorola Solutions et al., 3GPP RP-120362, “Public to achieve acceptable minimum data rates, for Safety Broadband High Power UE for Band 14 (B14) for example, to support video applications, as well Region 2.” IEEE Communications Magazine • February 2013 111C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND®
  • 7. C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND® ADDITIONAL READING broadband networks has led to his involvement with TIA TR-8 standards dealing with the application of LTE to pub- A [1] Federal Communications Commission, “Report and lic safety. His work is particularly involved with mission-crit- Order-Amendment of Part 90 of the Commission’s ical aspects of push-to-talk and other services. He has a Rules to Permit Terrestrial Trunked Radio (TETRA) Tech- Bachelor’s degree in mathematics from Lewis University, a nology,” WT-Docket no. 11-69, Sept. 2012. Master’s degree in computer science from Southern Illinois [2] TIA-102.AABA-B, “Trunking Overview,” Apr. 2011. University, and a Ph.D. in computer science from the Illi- [3] ETSI EN 300 392-1: “Terrestrial Trunked Radio (TETRA); nois Institute of Technology. He is currently a consulting Voice plus Data (V+D); Part 1: General Network member of technical staff in the Wireless Standards Design,” 2006. Department at Alcatel-Lucent Technologies. BIOGRAPHIES SAID TATESH (Said.Tatesh@alcatel-lucent.com) is the head of _________________ the 3GPP Standards Department at Alcatel-Lucent and T EWFIK L. D OUMI [SM] (tldoumi@lucent.com) received his ____________ responsible for the RAN standards projects for LTE, LTE- first degree in physics from Algiers University, Algeria, in Advanced, and UMTS. He received his M.Sc. and Ph.D. 1977, an M.S.E.E. degree from Stevens Institute of Tech- degrees in satellite and mobile communications in 1993 nology, Hoboken, New Jersey, in 1980, and a Ph.D. degree and 1997, respectively, from the Centre of Satellite and in electrical engineering from the University of Bradford, Engineering Research at the University of Surrey, United England, in 1991. After nearly 17 years spent in academia, Kingdom. Since joining Lucent Technologies in 1997 he has he joined Bell Laboratories at Lucent Technologies (now worked on multiple wireless projects in GSM, UMTS, LTE, Alcatel-Lucent) in 1997 to work on wireless systems design and LTE-Advanced. Currently, he is a technology director and reliability engineering. He is currently a principal in the leading the 3GPP standards teams in Alcatel-Lucent. He is Strategic Industries Division of Alcatel-Lucent leading a also the head of UMTS/LTE RAN Standards for both UMTS number of activities in the public sector domain, which and LTE, responsible for projects related to LTE enhance- includes public safety. While promoting and advocating ments such as public safety, device-to-device communica- with regulators and other stakeholders the rechanneliza- tions, push-to-talk, network MIMO, advanced antenna tion of the public safety spectrum to accommodate stan- systems, machine-to-machine communications, carrier dard commercial broadband technologies, he was Lucent’s aggregation, and so on. representative to TIA TR8.8 and the now defunct MESA group. He recently contributed as an SME to the develop- ALESSIO CASATI obtained a Master’s degree in computer and ment of the “Technical Advisory Board for First-Responders automation systems engineering from the Polytechnic of Interoperability” report and led the system design working Milan in 1995. He is with Alcatel Lucent, responsible for group during the development of the latest NPSTC Launch standardization of core network and systems aspects of Statement of Requirements. Both works are intended for 3GPP mobile systems He was previously involved in R&D of the implementation of the U.S. national public safety the UMTS packet core and with Italtel Central R&D for broadband network. He is the author of multiple journal video on demand systems, and IP and ATM networking and conference publications, and has two patents with projects. He has published two books in the area of con- seven pending. He is a Bell Labs Distinguished Member of vergence and mobile data networks. Technical Staff and a member of the Alcatel-Lucent Techni- cal Academy. GEORGE TSIRTSIS (tsirtsis@qti.qualcomm.com) is a principal _______________ engineer at Qualcomm, currently running the LTE-Direct MIKE DOLAN has been involved in the development of stan- project, which is introducing and standardizing D2D con- dards for cellular systems for over 25 years, beginning cepts into 3GPP/LTE. This effort follows over five years of when GSM was still being defined, and continuing through fundamental research on D2D as part of the FlashLinQ 2G, 3G, and 4G systems. His work has covered air interface project. Before joining Qualcomm, he was a network k signaling, access network protocol design, and core net- architect at Flarion Technologies, where he led the work signaling. Beginning with GSM, he has been involved design of network access and mobility management sub- in the expansion of 2G systems and their features, includ- systems of the Flash-OFDM IP-based cellular network. ing the radio access network (RAN) protocols to support Prior to that he worked at BT’s Research Labs in the soft handoff in CDMA systems to create more seamless United Kingdom, following an M.Sc. in telecommunica- voice calls. Progressing into 3G, where data became more tions Systems at Essex University, United Kingdom. He important, he has been involved with standardizing the holds 25 issued and many more pending patents, and technologies that support higher-speed data transfers, and has authored many IETF IDs and RFCs mainly in the area extend the Internet over the cellular radio interface, includ- of IPv6 and mobility, and was also involved with the def- ing both technical and leadership positions within the inition of EPC for LTE in 3GPP. 3GPP2 standards organization. With the development of 4G technologies, the introduction of voice over IP (VoIP) DINO FLORE received an M.S. degree in electrical engineering into cellular networks, and the creation of smartphones, from the Politecnico di Torino, Italy, and an M.S. degree in his work in cellular standards has become central to pro- mobile communications from the EURECOM Institute, viding wireless operators an evolution path from CDMA- France, in 2000. From 2001 to 2003 he worked at Array- based 3G systems to 4G LTE-based systems. This comm as a senior research engineer on smart antenna interworking effort has been his central focus for the past technology. In 2003 he joined Qualcomm, where he is cur- five years, leading him to become the editor of the two rently serving as a director of Technical Standards, with a major 3GPP2 standards documents involved with access leadership role in the area of 3GPP RAN standardization. network and core network interworking between EVDO he is also currently serving as Chairman of 3GPP RAN and LTE systems, and chair of the Packet Data Systems Working Group #3, to which he was elected in August (PDS) working group in 3GPP2. Public safety interest in 2009. 112 IEEE Communications Magazine • February 2013C qM IEEE M ommunications q qM Previous Page | Contents | Zoom in | Zoom out | Front Cover | Search Issue | Next Page MqM q Qmags THE WORLD’S NEWSSTAND®

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