Conference / Tutorials

Tutorial M1: Cognitive and Software Defined Radio Testing

by Thomas Braune, Tektronix GmbH, Germany  -  (Exhibition Sponsor of CrownCom 2009)

Software Defined Radios (SDRs) are driving the integration of digital signal processing (DSP) and radio frequency (RF) capabilities. This integration allows software to dynamically control communications parameters such as the frequency band used, filtering, modulation type, data rates and frequency hopping schemes. SDR technology is widely used in wireless devices for consumer products, commercial networks, military systems and specialized government applications. 
Compared to traditional RF technologies and implementations, SDR is superior because it enables the development of highly flexible and adaptable devices, allowing efficient device reconfiguration in response to changing requirements.
SDRs are used in several different markets, including:

  • Cellular, such as WCDMA, HSxPA, GSM, and CDMA2000
  • Military Tactical Radios, such as Joint Tactical Radio Service in the US
  • Land Mobile Radios, such as Project 25 in the US and other areas
  • “Regenerative” Satellite transceivers

Software Radios, however, introduce a host of new problems not present in traditional wireless analog designs. This presentation expands on the basic principles described in the Tektronix Application Note, Software Defined Radio: An Integrated Test Method for Designing Software Communications Architecture (SCA) Compliant Radios. Specific examples of common transmitter design issues and how to easily identify and diagnose them using a Real-Time Spectrum Analyzer (RTSA) will be presented.

Tutorial T1-1/2: Cognitive elements in RRM and DSA

by Oriol Sallent, Jordi Perez, and Ramon Agusti, Universitat Politecnica de Catalunya (UPC), Spain

This tutorial will introduce some cognitive elements to enhance both Radio Resource Management (RRM) and Dynamic Spectrum Assignment (DSA) strategies in modern wireless networks by means of learning from the environment and acting accordingly. Specific relevance will be given to Joint Radio Resource Management in B3G networks, and DSA in next OFDMA deployments. Finally some case studies will be presented under the recently proposed Private Commons regulation on spectrum sharing.

Tutorial W1-1/2: Cognitive Radio Networks in TV White Spaces: Regulation, Theory and Practice

by Dave Cavalcanti, Monisha Ghosh Philips Research, USA;  Milind M. Buddhikot, Alcatel-Lucent Bell Labs, USA

Recently, new policies and regulatory rules for more efficient allocation and utilization of radio spectrum have been released. In the USA, the FCC TV band white space rules announced in November of 2008 is most recent example. Other regulatory bodies around the world are also actively considering similar policies to enhance spectrum utilization and promote innovation. This new regulatory landscape brings about a great opportunity for the cognitive radio research and industry communities, which will be able to put in practice the Cognitive Radio technology developed in the recent years as well as to generate and demonstrate innovative solutions to harness the spectrum opportunities in the TV band.
The TV band spectrum is allocated primarily to broadcasting services, however, measurements have indicated that parts of the spectrum are virtually unused, such “spectrum holes” are known as spectrum white spaces. These white spaces are seen as opportunities for better utilization of the radio spectrum and for enabling new wireless and mobile applications. In its most recent proposed regulation, the FCC has enabled the use of TV band white spaces on a secondary basis for both fixed and personal/portable devices. However, the rules impose several requirements to TV band incumbent protection, that is, avoid interference with TV broadcasting services as well as low power wireless microphones. The Cognitive Radio is the key technology to harness such TV white spaces due to its capabilities to identify spectrum opportunities and adapt the radio’s operating characteristics to the real-time conditions of the environment. However, designing and deploying Cognitive Radio Networks in TV white spaces involves a number of challenges in a multitude of angles, including spectrum availability detections, medium access and networking protocols, coexistence mechanisms, security, regulatory compliance, and so on.
This tutorial presents the current regulatory landscape for utilization of TV white spaces, describes the various spectrum access models and use cases for TV white spaces, presents the theory behind several Cognitive Radio technologies that can be used in the TV white spaces, such as incumbent protection mechanisms, spectrum sensing, medium access and networking protocols, and self-coexistence mechanisms. The tutorial also provides an overview of current standardization activities as well as open research issues in the Cognitive Radio Networks. Furthermore, the tutorial will discuss practical developments in Cognitive Radio Networks, including TV white space sensing prototypes, cognitive radio platforms and a TV white space cognitive radio network for wireless home networking applications.

Tutorial W2: Technical overview of the IEEE 1900.4 standard - Architectural building blocks enabling distributed decision making for optimized radio resource usage in heterogeneous wireless access networks

by S. Filin, H. Harada, H. Murakami, K. Ishizu, National Institute of Information and Communications Technology (NICT), Japan

Today wireless environment is characterized by multiple operators providing different services in various frequency bands using different radio access technologies (RAT). Such heterogeneous wireless environment gives users a lot of options to manage their subscriptions.

On the other hand, such environment has generated new technical challenges for regulatory bodies, operators, and equipment manufacturers. The key issue in heterogeneous wireless environment is efficiency of spectrum usage, which contributes to both operator revenue and user satisfaction. The background of this issue is fixed spectrum allocation. Multiple measurement campaigns have been performed to show that large parts of allocated frequency bands remain unused for quite long periods of time. Based on these observations, multiple concepts of dynamic spectrum access have been developed.

Current level of hardware and software technology makes it possible and economically efficient to implement dynamic spectrum access concepts in commercial heterogeneous wireless networks. Reconfigurable base stations and terminals enabled by software defined radio technology and supporting different RATs in different frequency bands have already become a reality in commercial products.

The only remaining gap here is intelligent management system, which can be deployed on top of the heterogeneous wireless environment in order to optimize spectrum usage and thus increase operator benefits and user satisfaction.

IEEE 1900.4 standard, started in February 2007 and published in February 2009, has filled this gap by defining “architectural building blocks enabling network-device distributed decision making for optimized radio resource usage in heterogeneous wireless access networks.” It has been developed within the IEEE SCC 41 committee.

This tutorial comprises three parts:

1.      Overview of IEEE SCC41 standards for dynamic spectrum access networks

2.      Technical overview of IEEE 1900.4 standard

3.      Presentation of developed cognitive radio systems based on IEEE 1900.4 standard.