A Roadmap to International Standards Development for Cognitive Radio Systems and Dynamic Spectrum Access

This chapter provides a summary of standards activities related to cognitive radio systems (CRS) and dynamic spectrum access (DSA) systems. Because of the vast amount of standardization activity in this arena, this chapter can provide only a high-level snapshot of current CRS/DSA standardization activities and a projection of activities expected in the near future. Sufficient references including URL references are included so that the interested reader can review in as much detail as desired the standards that have and are being developed by numerous international standards development organizations (SDOs). These standards will be evolving in time as will be described later in this chapter in the descriptions of the various SDOs. It is expected that standardization in this arena will continue by these SDOs for at least the next decade.


Introduction
This chapter provides a summary of standards activities related to cognitive radio systems (CRS) and dynamic spectrum access (DSA) systems. Because of the vast amount of standardization activity in this arena, this chapter can provide only a high-level snapshot of current CRS/DSA standardization activities and a projection of activities expected in the near future. Sufficient references including URL references are included so that the interested reader can review in as much detail as desired the standards that have and are being developed by numerous international standards development organizations (SDOs). These standards will be evolving in time as will be described later in this chapter in the descriptions of the various SDOs. It is expected that standardization in this arena will continue by these SDOs for at least the next decade.
Section 2 sets the stage by describing the terminology that is used by researchers and practitioners because there are many terms closely related to CRS and DSA. As noted in Section 2, there is not total agreement on definitions between the various standards development organizations. Section 3 describes how standards development for CRS/DSA is but one piece of the puzzle that must be solved in order for CRS/DSA systems to achieve their full potential. In that sense, Section 3 can be viewed as the statement of the problem. In order to solve the standardization portion of the puzzle, numerous international SDOs are working on different pieces of the standardization puzzle. The work of these SDOs is described in Sections 4 through 6. A brief summary and a description of future standards work are both provided in Section 7.

IEEE 802
The IEEE 802 Standards Committee develops standards for local and regional networks. This organization has focused on CRS/DSA for TV white space bands. Some of the difficulty in the terminology is related to the fact that some of the functionality typically associated with cognitive radios is outside the functionality of what is historically associated with a "radio." As will be described in Section 5.1.1, the Institute of Electronics and Electrical Engineers (IEEE) Standard IEEE 1900.1 TM addresses the terminology issue and discusses basic concepts associated with several technologies related to CRS.
There are many terms that are being used in the literature being used that are closely related to CRS technology including dynamic spectrum access, software defined radio, hardware radio, adaptive radio, policy-based radio, reconfigurable radio, and software-controlled radio. In this chapter we focus on standards for CRS and DSA which have been defined as:


Cognitive Radio System: "A radio system employing technology that allows the system to obtain knowledge of its operational and geographical environment, established policies and its internal state; to dynamically and autonomously adjust its operational parameters and protocols according to its obtained knowledge in order to achieve predefined objectives; and to learn from the results obtained." (ITU-R, 2009 (operational mode, battery life, location, etc.), interferenceavoidance (either suffered or inflicted), changes in environmental/external constraints (spectrum, propagation, operational policies, etc.), spectrum-usage efficiency targets, quality of service (QoS), graceful degradation guidelines, and maximization of radio lifetime." (IEEE 2008a).

Standards -A critical part of the evolution to CRS
As conceptualized in Figure 1, the full potential of cognitive radio systems is dependent upon activities in the following areas:  Economic feasibility based on business case scenarios:  User requirements which drive new business cases which in turn drive the need for more spectrum (e.g., 4 th generation commercial wireless).  New radio system technologies (e.g., ultra wideband, policy-based DSA radio systems, cognitive radio systems) and networks which utilize these radio system technologies -these new technologies open up new business opportunities.  Technology Development:  Responsive to new users requirements which frequently require significant new spectrum.  Responsive to the need for more efficient use of the spectrum.  Responsive to, and drives, new regulatory proceedings (e.g., DSA radios and networks, policy-based radio, software defined radio, ultra wideband radio (UWB), cognitive radio systems, etc.) and new questions within the ITU-R.  Regulatory and policy changes:  Regulatory changes that recognizes new requirements and new technologies.  Regulatory changes for CRS and DSA are driven by need for a new paradigm for spectrum management to accommodate requirements for additional spectrum (e.g., the need for more spectrum for cellular systems to support wideband applications such as audio and video steaming).
As depicted in Figure 1, technical standards are a central part needed to bring the above components together to enable the fielding of CRS and DSA-based systems. One example of this is the development of IEEE 802 standards for TV white space as will be described later in this chapter.
Another example is the development of standards relative to advanced mobile telecommunications systems over the last several years. Clearly there is a business case as can be seen for the broadband applications. This required the consideration by the ITU-R and by national regulatory agencies for the identification of additional spectrum to support these new broadband applications. Technologies were developed to support these applications -these technologies were then standardized by the 3rd Generation Partnership Project (3GPP), IEEE, the ITU-R, and other standards organizations. Although this example does not specifically include CRS/DSA, these technologies are envisioned as being a part of the solution in future years for the continued evolution of mobile telecommunications requirements and the identification of spectrum to satisfy these ever increasing requirements. As will be described in later sections, the IEEE and the ITU-R have both been working on standards and reports relative to CRS/DSA for mobile telecommunication applications.

International Telecommunication Union Radiocommunication Sector
In our discussion of standards for CSA/DSA, a logical starting place is the International Telecommunication Union Radiocommunication Sector (ITU-R). The ITU-R is the sector of the ITU of primary relevance to this chapter because of its role as a primary global forum on the evolution of radio technologies and because of its decisions on spectrum allocations necessary for this evolution. Information on other sectors of the ITU as well as ITU-R may be found at www.itu.int.
The Radio Regulations (RR) is one of the most significant products of the ITU-R and is published in the 6 official languages of the ITU. (ITU-R, 2008) The Radio Regulations document is the international treaty governing the use of the radio-frequency spectrum and the geostationary-satellite and non-geostationary-satellite orbits.

World Radiocommunication Conference Agenda Item 1.19 and Resolution 956
The World Radiocommunication Conference (WRC) is organized by ITU to review and revise as necessary the ITU-R Radio Regulations. An important topic for the next WRC (January 2012 in Geneva) are issues related to software defined radio and CRS/DSA. One of the many Agenda Items of WRC-12 is Agenda Item 1.19: "To consider regulatory measures and their relevance, in order to enable the introduction of software-defined radio and cognitive radio systems, based on the results of ITU-R studies, in accordance with Resolution 956 of WRC-07." (ITU-R, 2007a).

ITU-R Resolution 956 states in part (ITU-R, 2007a):
"resolves to invite ITU-R 1. to study whether there is a need for regulatory measures related to the application of cognitive radio system technologies; 2. to study whether there is a need for regulatory measures related to the application of softwaredefined radio.
Resolves further that WRC-11 consider the results of these studies and take the appropriate actions. 1 The ITU-R studies relative to the potential need for additional regulatory measures is a critical step in the evolution of CRS. As previously discussed in regard to Figure 1, regulatory policies are one of the critical piece-parts in the evolution of CRS/DSA. Technologies which are developed to satisfy the business cases for CRS/DSA must be compliant with existing regulatory measures. The starting point for these regulatory measures is the ITU-R Radio Regulations. The following section provides information on the work of ITU-R Study Groups and Working Parties that are underway to satisfy Resolution 956. These results will be reviewed during WRC-12 as part of discussions relative to WRC-12 Agenda Item 1.19. Because of the complexity of the regulatory issues, it can reasonably be expected that these studies will be continued beyond WRC-12, i.e., into the next ITU-R Study Period and probably even beyond that although there may not be a continuation of the agenda item.

Conference Preparatory Meetings
There are two Conference Preparatory Meetings between WRCs; one is immediately after the conclusion of a WRC and is known as CPM1; the second CPM typically is a few months before the following WRC and is known as CPM2. CPM1 develops the program of study for the ITU-R Study Groups. CPM2 prepares a consolidated report to be used in support of the work of World Radiocommunication Conferences, based on:  contributions from administrations and the Radiocommunication Study Groups concerning the regulatory, technical, operational and procedural matters to be considered by the following WRC;  the inclusion, to the extent possible, of reconciled differences in approaches as contained in the source material, or, in the case where the approaches cannot be reconciled, the inclusion of the differing views and their justification. (ITU-R, 2007b).

ITU-R study groups and working parties
One of the major activities of the ITU-R is that associated with the ITU-R Study

ITU-R Study Group 1 -Spectrum Management
The purpose of Study Group 1 (SG 1) is the development of "spectrum management principles and techniques, general principles of sharing, spectrum monitoring, long-term strategies for spectrum utilization, economic approaches to national spectrum management, automated techniques and assistance to developing countries in cooperation with the Telecommunication Development Sector." (ITU-R, 2010).
Working Party 1B (WP1B) is the Working Party under SG 1 that is responsible for the development of spectrum management methodologies and economic strategies. WP1B is responsible for Agenda Item 1.19 and is working on developing a response which will be sent from Study Group 1 to the CPM2 for WRC-12 in response to Resolution 956 from WRC07. This work within ITU-R is likely to continue well beyond WRC12 but is likely to be focused on additional studies that generate ITU-R Reports and ITU-R Recommendations rather than changes to the Radio Regulations.

ITU-R Study Group 5 -Terrestrial Services
ITU-R QUESTION 241-1/5 is entitled, "Cognitive Radio Systems in the Mobile Systems." And is assigned to ITU-R Working Party 5A (Land mobile service above 30 MHz*(excluding IMT); wireless access in the fixed service; amateur and amateur-satellite services). There are several parts of Question 241-1/5 (ITU-R, 2010). however, the key part of the Question is: "How can cognitive radio systems promote the efficient use of radio resources?" Although, WP5A has been assigned this Question, other Working Parties within Study Group 5 are also working on this topic. For example, ITU-R WP5D (International Mobile Telecommunications Systems) is working on an ITU-R Report entitled, "Cognitive radio systems specific for IMT systems." In the ITU-R, the term International Mobile Telecommunications (IMT) means a family of radio interfaces for mobile telecommunication services. The term is applied to 3 rd and 4 th generation commercial mobile telecommunication services.
A primary difference between the work of WP5A and WP5D on CRS is in their focus; whereas WP5D is focused on the IMT application of CRS, WP5A is focused primarily on non-IMT applications of CRS. Although the current reports being developed within ITU-R Working Parties 5A and 5D are likely to be completed in the near future, it is likely that work in this arena by these two working parties is likely to continue for several years. It is expected that ITU-R Recommendations and additional ITU-R Reports will be produced in addition to the ITU-R Reports currently being developed.

Other ITU activities
Radiocommunication Assemblies (RA) are responsible for the structure, program and approval of Radiocommunication studies. They are normally convened every three or four years and may be associated in time and place with World Radiocommunication Conferences (WRCs). Amongst other responsibilities, the Assemblies are responsible for:

IEEE standards development related to CRS and DSA
A number of papers have been published in recent years that provide snapshots of international standards activities on CRS/DSA including those of the Institute of Electrical and Electronics Engineers (IEEE). (Sherman, et. al. 2008;Prasad, et. al., 2008;Granelli, et. al., 2010, andStanislav, et. al. 2011

IEEE DySPAN Standards Committee
The DySPAN (Dynamic Spectrum Access) standards committee had its beginning in early 2005 jointly under CSSB and EMC. It was initially known as the 1900 Committee and later as the Standards Coordinating Committee 41 (SCC41). The scope of the DySPAN-SC includes the following:  dynamic spectrum access radio systems and networks with the focus on improved use of spectrum,  new techniques and methods of dynamic spectrum access including the management of radio transmission interference, and  coordination of wireless technologies including network management and information sharing amongst networks deploying different wireless technologies.
Additional information on DySPAN-SC may be found at www.dyspan-sc.org. x WGs have completed baseline standards and will be developing follow-on standards that are extensions of the baseline standards. Therefore, it is expected that each of these IEEE 1900.x WGs will be in existence for many years. The IEEE 1900.1 WG is responsible for DSA definitions and concepts and published its first standard in 2008. This standard provides definitions and explanations of key concepts in the fields of spectrum management, cognitive radio, policy-defined radio, adaptive radio, software-defined radio (SDR), and related technologies. The standard goes beyond simple, short definitions by providing amplifying text that explains these terms in the context of the technologies that use them. The document also describes how these technologies interrelate and create new capabilities while at the same time providing mechanisms supportive of new spectrum management paradigms such as CRS and DSA. (IEEE 2008a).
The body of this standard is "normative" meaning that the material is a required part of the standard. Because of the complexity of the technology, the 1900.1 Standard provides amplifying material in "informative" annexes. Although these "informative" annexes are not a required part of the standard, these annexes are helpful to users of the standard in fully understanding the meaning of the "normative" definitions. A key annex is the annex that describes the relationship of terms such cognitive radio, software defined radio, software-controlled radio, intelligent radio, policy-based radio, and reconfigurable radio.
The IEEE 1900.1 Standard TM defines "cognitive radio" (CR) and "cognitive radio network" but does not define "cognitive radio system" which is a term defined by the ITU-R and the US National Telecommunications and Information Administration and provided earlier in this chapter. (ITU 2009 andNTIA 2011). The IEEE and ITU-R definitions for CR and for CRS respectively are consistent however. The note in the IEEE definition for CR states the cognitive functionality typically associated with a cognitive radio is beyond the functionality normally associated with a "radio." The key is having a common understanding of what is meant by "radio." The IEEE 1900.1 Standard TM defines "radio" as being a "technology for wirelessly transmitting or receiving electromagnetic radiation to facilitate transfer of information." In this context, it is important to understand and differentiate between "radio" and "radio systems." Radio systems include software control of the radio proper. This radio control may include cognitive and adaptive features. The IEEE 1900.1 Standard TM provides figures and text useful in the understanding of these aspects of cognitive radio, cognitive radio systems and radio control mechanisms. Figure 4 is an illustration of a basic concept derived from the concepts provided in the IEEE 1900.1 Standard TM . The figure illustrates what is meant by software control of a software defined radio. A software defined radio is defined by IEEE 1900.1 Standard TM as: A type of radio in which some or all of the physical layer functions are software controlled. Software control is the use of software processing within the radio system or device to select the parameters of operation.
The parameters of operation include the radio frequency (rf), the modulation, the transmitted power level, etc., i.e., the parameters that one typically associations with radio operation. In a software defined radio, some or all of these radio operational parameters may be implemented in software and may be changed by a real-time software control mechanism. The software control mechanisms may be very complex and may include cognitive and adaptive functionality that responds in real-time to a changing rf environment, changing operational policies, changing location, etc. More will be said in Section 5.1.5 about the policy-based radio control mechanism. Fig. 4. Illustration of software control of software defined radio

IEEE 1900.2 Working Group
The IEEE 1900.2 WG has produced a standard which provides technical guidelines for analyzing the potential for coexistence or, by way of contrast, interference between radio systems operating in the same frequency band or between different frequency bands. (IEEE, 2008b). Additional work in this arena is needed and is likely to be conducted by one or more of the IEEE 1900.x WGs that operate under the DySPAN-SC.

IEEE 1900.3 Working Group
The IEEE 1900.3 WG was dissolved prior to the completion of any standard. It was chartered to produce a standard which would:  specify techniques for testing and analysis to be used during compliance and evaluation of radio systems with dynamic spectrum access capability, and which would  specify radio system design features that simplify the evaluation challenge.
The potential for deployment of CRS/DSA systems may be affected by the ability of regulatory agencies and industry stakeholders to verify that a system conforms to applicable technical and policy requirements. This standard enables coordinated network-device distributed decision making which will aid in the optimization of radio resource usage, including spectrum access control, in heterogeneous wireless access networks. The standard is limited to the architectural and functional definitions at a first stage. The corresponding protocols definition related to the information exchange is now being addressed during a second stage of IEEE 1900.4 WG activities.
The purpose of the IEEE 1900.4 project is to improve overall composite capacity and quality of service of wireless systems in a multiple Radio Access Technologies (RATs) environment, by defining an appropriate system architecture and protocols which will facilitate the optimization of radio resource usage.
In addition to the baseline IEEE 1900.4 Standard TM , an amendment to this standard has recently been completed. (IEEE 2011a). This amendment modifies the IEEE 1900.4 standard to enable mobile wireless access service in white space frequency bands without any limitation on used radio interface (physical and media access control layers, carrier frequency, etc) by defining additional components of the IEEE 1900.4 system. This amendment is integrated into the baseline standard.
An additional project of the IEEE 1900.4 working group is the P1900.4.1 project which enhances the baseline standard by providing detailed specification of interfaces and service access points defined in the baseline standard, This enables distributed decision making in heterogeneous wireless networks and the use of context information for this decision making.

IEEE 1900.5 Working Group
The IEEE 1900.5 WG has produced a standard which defines a vendor-independent set of policy-based control architectures and corresponding policy language requirements for managing the functionality and behaviour of dynamic spectrum access networks. This standard also defines the relationship of policy language and architecture to the needs of at least the following constituencies: the regulator, the operator, the user, and the network equipment manufacturer. (IEEE 2012). Figure 5 is a simplified user interpretation of the architecture provided in the IEEE 1900.5 Standard TM for a policy-based DSA radio system (PBDRS) functional architecture. This figure may be viewed as an expansion of the more general architecture provided in Figure 4. The additional details are those involved in the software control mechanism and consist of the system strategy reasoner (SSR), the policy enforcer (PE) and the policy conformance reasoner (PCR). Essentially these components are designed to ensure compliance by the PBDRS to policies which may change depending on many parameters such as user requirements, rf environment, geographical location, etc. Some of these changes may be real-time; for example changes to the CRS operations due to changes in the rf environment. This type of capability is needed to reach the ultimate goal of more efficient use of the spectrum. The PCR, SSR and the PE represent functionalities that may be distributed, i.e., this functionality may not reside within a single radio device or even within a radio node. This is the reason for the emphasis on the system and network and not just the radio per se (meaning not just the receiver and transmitter aspect).
The policies that come from the policy management point (PMP) may be regulatory policies, operational policies or even user policies. The input to the PMP may be human readable policies that are converted into digital policies that are machine readable.
The IEEE 1900.5 Standard TM (IEEE 2012) describes the communications between the SSR, PE and PCR which are shown in Figure 5; however the standard does not specify the details of these interfaces. One follow-on standard to the base standard will specify these interfaces in detail. The detailed specification of these interfaces may be helpful to regulatory agencies that will be addressing certification issues for these types of radios which can be viewed as a new paradigm. Information from the research community including ComSoc Technical Committees such as the Technical Committee on Cognitive Networks will be helpful in the development of this follow-on standard.

A Roadmap to International Standards Development for Cognitive Radio Systems and Dynamic Spectrum Access 289
In addition to the functional architecture just described, the IEEE 1900.5 Standard TM also describes requirements for a policy language to be used by the PCR. This language will be a declarative language. This type of language expresses what is to be accomplished rather than how it is to be accomplished. This is in contrast to languages such as C, C ++ , and Java which are imperative or procedural languages that manipulate the state of the program through an executed sequence of commands specified by a control structure. A follow-on to the IEEE 1900.5 Standard TM will provide a detailed specification of this policy language based on the requirements listed in the base standard.

IEEE 1900.6 Working Group
The IEEE 1900.6 WG has produced a standard which defines the information exchange between spectrum sensors and their clients in radio communication systems. The logical interface and supporting data structures used for information exchange are defined abstractly without constraining the sensing technology, client design, or data link between the sensor and client. The purpose of this standard is to define spectrum sensing interfaces and data structures for DSA systems and other advanced radio communications systems that will facilitate interoperability between independently developed devices and thus allow for separate evolution of spectrum sensors and other system functions. (IEEE 2011b).
The standard contains system models that allow for multiple sensors and for multiple cognitive engines or data archives. In other words, the sensor data acquisition can be distributed with multiple sensors, the sensor processing can be distributed with multiple cognitive engines, and the sensor data storage can be distributed with multiple data archives.
Sensing of the rf environment is a critical part of the original CRS/DSA concept. It is well recognized, however, that sensing of the rf environment is itself not always sufficient to have a realistic picture of the rf environment. For instance, sensing will not detect the usage of spectrum by some passive users of the spectrum such as radio astronomy. Therefore, sensing may need to be supplemented with other sources of information on the rf spectrum usage such as data bases. Chouinard (2010) discusses the practical limits to rf sensing and specifically notes that although it is a good approach to be considered in general for cognitive radio, it has been a challenge for us in the TV white space bands.

IEEE 1900.7 Working Group
In June 2011, the IEEE 1900.7 WG commenced work on a standard that specifies a radio interface including medium access control (MAC) sublayer(s) and physical (PHY) layer(s) of white space dynamic spectrum access radio systems supporting fixed and mobile operation in white space frequency bands, while avoiding causing harmful interference to incumbent users in these frequency bands. The standard provides supports the IEEE 1900.4 Standard TM , the IEEE 1900.4a Amendment (IEEE (2011a) for white space management, and the IEEE 1900.6 Standard TM to obtain and exchange sensing related information (spectrum sensing and geolocation information).
The IEEE P1900.7 Standard will enable the development of cost-effective, multi-vendor white space dynamic spectrum access radio systems capable of interoperable operation in white www.intechopen.com

Foundation of Cognitive Radio Systems 290
space frequency bands on a non-interfering basis to incumbent users in these frequency bands. This standard facilitates a variety of applications, including the ones capable to support high mobility, both low-power and high-power, short-, medium, and long-range, and a variety of network topologies. This standard is a baseline standard for a family of other standards that are expected to be developed focusing on particular applications, regulatory domains, etc.
One result of TV broadcasting systems being upgraded from analog to digital technology is that it frees up channels under certain conditions (e.g., that the channel is not being used by licensed wireless microphones). Unlike the white space work in IEEE 802 which is discussed later in this chapter, the IEEE 1900.7 WG is not focused on the TV white space bands (TVWS). The intent of 1900.7 is the development of a family of standards that could be used for any portion of the spectrum having white space, i.e., spectrum that is not being utilized.

IEEE 802
The The work of the 802 WGs is a practical example of the concepts illustrated in Figure 1 regarding relationships between standards development, technology, and regulatory policies. The work of these WGs is a direct result of decisions made by regulatory agencies regarding TV white space. (FCC 2004, FCC 2008, FCC 2011 This standard will be known as IEEE 802.11af. The main difference between this standard and other members of the well known IEEE 802.11 family of standards is that IEEE802.11af will be a based on cognitive radio for operation in the TV White Spaces. The TV White Spaces is spectrum already allocated to the TV broadcasters but is not being used. The only additional prerequisite for IEEE 802.11af in the US, is the need for a database that maintains data about used frequencies in the TV band.
With the global transition to digital TV, sub-Gigahertz rf spectrum is becoming available. Much of this spectrum is for unlicensed, license exempt and/or lightly licensed use. The IEEE 802.11af standard will make the necessary MAC and PHY changes to enable 802.11 products to take advantage of this additional spectrum.

IEEE 802.19 -Wireless Coexistence WG
The IEEE 1900.1 WG  develops standards for coexistence between wireless standards of unlicensed devices, and  reviews coexistence assurance (CA) documents produced by other IEEE 802 WGs developing new wireless standards for unlicensed devices.
The IEEE 802.19.1 subgroup is in the process of developing a standard entitled:

Standard for Information Technology -Telecommunications and Information Exchange Between Systems -Local and Metropolitan Area Networks -Specific Requirements -Part 19: TV White Space Coexistence Methods
The purpose of the standard is to enable the family of IEEE 802 Wireless Standards to most effectively use TV White Space by providing standard coexistence methods among dissimilar or independently operated TV band devices (TVBD) networks and dissimilar TVBDs. This standard addresses coexistence for IEEE 802 networks and devices and will also be useful for non IEEE 802 networks and TVBDs. Completion in 2012. http://ieee802.org/19/index.html

IEEE 802.22 -Wireless Regional Area Networks WG
The IEEE 802.22 Working Group on Wireless Regional Area Networks (WRANs) is responsible for developing standards for a cognitive radio-based PHY/MAC/air interface for use by license-exempt devices on a non-interfering basis in spectrum that is allocated to the TV Broadcast Service.
The IEEE 802.22 WRAN Standard uses cognitive radio techniques to allow sharing of geographically unused spectrum allocated to the television broadcast service, on a noninterfering basis. The goal is to bring broadband access to hard-to-reach, low-populationdensity areas which are typical of rural environments. A particularly difficult problem is that of ensuring that there is no interference to low-powered licensed devices such as wireless microphones.
IEEE 802.22 Provides Three Mechanisms for Incumbent Protection: One or more protection mechanisms can be adopted based on the regulatory domain requirements. Stevenson, et.al (2009) and Mody and Chouinard (2010)

Other activities related to standards for CRS and DSA
There are numerous other organizations that are involved either directly or indirectly in the development of national and international standards for CRS, DSA and related technologies. It is not possible in this short chapter to discuss all of these organizations. One source that provides a list of standards setting organizations (SSOs)  The 3GPP and other organizations create specifications that are responsive to ITU-R Recommendations. These specifications are then adopted by the ITU-R.
The following subsections briefly describe some other organizations involved in CRS/DSA and related technologies. The list is not considered to be all inclusive.

European Telecommunications Standards Institute
The European Telecommunications Standards Institute (ETSI) produces globally-applicable standards for information and communications technologies (ICT), including fixed and mobile telecommunications and internet technologies. ETSI is officially recognized by the European Union as a European Standards Organization. ETSI has more than 700 member organizations from 62 countries in 5 continents. The ETSI RRS TC comprises four WGs (Mueck, 2010a).:  WG1 focuses on system aspects and develops proposals from a system aspects point of view for a common framework in RRS TC.  WG2 focuses on SDR technology with a particular interest in radio equipment architecture and proposes common reference architectures for SDR/CR radio equipment.  WG3 focuses on cognitive management and control including a functional architecture for radio resource management and a cognitive pilot channel.  WG4 focuses on public safety and collects and defines the related RRS requirements from relevant stakeholders in the public safety and defense domain.
These ETCI RRS TCs have completed numerous studies regarding CRS, SDR, and CR as the result of several Europe Union funded programs. One focus now in ETSI RRS TC is on utilizing the results of these research studies in developing appropriate normative standards. Mueck (2010b) provides additional information.

Ecma International
Ecma International was originally founded as the European Computer Manufacturers Association; however the name is now officially Ecma International without reference to the original ECMA acronym. Since 1961 Ecma International and its predecessor organization have developed international standards in information technology and telecommunications. More than 370 Ecma Standards and numerous Technical Reports have been published, many of which have also been adopted as international standards and/or technical reports.
Ecma International has published a standard on medium access control layer (MAC) and physical layer (PHY) specifications for operation in TV white space. (Ecma, 2009). This standard specifies MAC and PHY for personal/portable cognitive wireless networks operating in TV bands. The standard also provides specifications for higher layer protocols. It specifies a number of incumbent protection mechanisms available to meet regulatory requirements.

A Roadmap to International Standards Development for Cognitive Radio Systems and Dynamic Spectrum Access 295
More information may be found at: http://www.ecma-international.org/activities/index.html

IEEE ComSoc technical committees
The IEEE Communications Society has more than 24 technical committees. These technical committees define and implement the technical directions of ComSoc. All ComSoc Members are encouraged to participate in one or more of these technical committees. These committees usually meet twice a year at major conferences. Throughout the year, these committees also play a major role in determining which events (conferences, workshops, etc.) are technically co-sponsored by ComSoc. More information may be found at: http://www.comsoc.org/about/committees/Technical

Wireless Innovation Forum
The Wireless Innovation Forum™ (WInF) is a non-profit corporation whose predecessor organization was started in 1996. Formerly known as the SDR Forum, the WInF is dedicated to driving technology innovation in commercial, civil, and defense communications worldwide. The focus of the WInF is on SDR, CR, and DSA. The Forum has produced many technical reports on these topics. The Forum is not an internationally accredited standards development organization. However, the technical reports developed by the Forum have been input to standards organizations such as IEEE DySPAN-SC and ITU-R. For example, the Forum contributed many inputs to the development of the IEEE 1900.1 Standard TM .
More information on the Wireless Information Forum may be found at: http://www.wirelessinnovation.org/page/About_the_Forum

WRAN Alliance
The Wireless Regional Area Network (WRAN) Alliance promotes products and services based on wireless telecommunications standards for broadband services using TV band frequencies.
The WRAN Alliance has the objective of promoting standards that will permit the provision of broadband connectivity at reasonable cost in rural areas and in developing areas. This is viewed by the WRAN Alliance as a means bridging the digital divide. More information on WRAN Alliance may be found at: www.wranalliance.org/

Wireless World Research Forum
The objective of the Wireless World Research Forum (WWRF) is to formulate visions on strategic future research directions in the wireless field, among industry and academia, and to generate, identify, and promote research areas and technical trends for mobile and wireless system technologies. The WWRF is not an internationally accredited standards development organization. However, the results of the WWRF research have significant impact on the direction of standards development in many international standards development organizations. The WWRF has one group focused on cognitive networks for wireless internet and another on spectrum issues.
More information may be found at: http://www.wireless-world-research.org/

Conclusion and future work
This chapter has provided a roadmap to international standardization activities for cognitive radio systems, DSA systems and related technologies. Numerous standards have already been published by several standards bodies. In addition, there are many technical reports related to standards that have developed and are continuing to be published by a variety of organizations such as the ITU-R, WWRF, ETSI, and the Wireless Innovation Forum. Although these technical reports are not standards per se, they nevertheless provide the foundation for future standards development.
To a certain extent this roadmap to CRS/DSA standards development could be considered to be a snapshot in time. However, the information on organizations and standards provided herein is essentially a description of the foundations of the CRS/DSA standardization effort. It is anticipated that all of the organizations mentioned herein will still be active in CRS/DSA standardization for at least the next decade. Furthermore, it is anticipated that the specification standards mentioned herein are in most cases baseline standards that are the foundation for work that will be ongoing for the next decade or more.
The CRS/DSA standardization effort is very complex because ultimate success of this technology is dependent on the efforts of the regulatory, technical research, standards development, and business communities. Although these communities are all part of the effort for ultimately successfully fielding these technologies, these communities work independently.
A driving force is the need to more efficiently utilize the rf spectrum. Thus, additional regulatory action may be needed to free up more spectrum for CRS and DSA --the FCC rulings related to TV white space provide an example of what may be forthcoming. But clearly, these www.intechopen.com A Roadmap to International Standards Development for Cognitive Radio Systems and Dynamic Spectrum Access 297 types of rulings can be controversial. The research community can come up with technology proposals for better utilization of the spectrum, but it must be within regulatory boundaries. Standards development organizations can develop new standards that incorporate results from the research community, but these standards also must stay within the regulatory boundaries. But the regulatory boundaries can be changed depending on the influence of industry on regulators -this influence is the result of business cases for the use of spectrum.
Finally, it can be expected that the ITU-R, IEEE DySPAN-SC, IEEE 802 and many other organizations identified in this chapter will continue their standardization efforts for at least another decade. Regulatory boundaries, technology, business requirements will all evolve during this period of time and will be driven by the need to more efficiently utilize the spectrum.