Throughout the world, countries and regions rely on radio spectrum management techniques to manage the finite resources of the radio spectrum and the growth of their telecommunications infrastructure.
As new databases containing terrain, environment, urban and building data are made available, new automated frequency wave propagation prediction models are being deployed. The discipline of frequency management utilizes these propagation models to evaluate the interactions between co-located frequency assignments to ensure station operators do not interfere. Spectrocan delivers these models in their Automated Frequency Management System (AFMS) using Esriís ArcGIS, ArcSDE, and ArcIMS platforms.
The following paper discusses how adding the spatial dimension has streamlined the spectrum evaluation process, improved the technical analysis and accuracy of the wave propagation models, and enhanced revenue generating capabilities for national and regional spectrum management agencies.
In the past, telecommunication companies spent substantial time and money designing and developing networks for new services. These designs were usually done by hand and the resulting application was submitted to the national or regional regulator for approval.
The application process is usually a nationally regulated policy that governs the information required to gain a license to operate within the frequency spectrum. The telecom company will design the infrastructure and stationís frequency configuration along national guidelines and submit a formal application to the regulatory agency. The regulator accepts the application and reviews the frequency configuration through a process called technical analysis. The technical analysis models the application design against the existing licensed stations to ensure the applications frequencies do not cause interference with existing assignments. The results of the technical analysis allow the spectrum engineer to approve the new frequency allocation or suggest configuration changes. The entire process has financial milestones and regulator approval warrantees interference free frequency assignments.
However, rarely would the spectrum engineer approve the new frequency assignment without some change to tower position, frequency or power. The suggested changes would then be sent back to the applicant to make modifications and re-submit. The time to redesign and re-submit may take weeks or even months. In the mean time, other frequencies may be licensed within the same frequency band and area, there by impacting the viability of the second round of changes.
Overall the time from design to implementation of new telecommunication infrastructure was long, resulting in lost revenue to the telecom company. As design and implementation times shorten, the application process becomes the bottle-neck prohibiting advancement of the telecom infrastructure.
Frequency Management Systems Use of GIS
Canada has an international reputation for its ability to efficiently manage its frequency spectrum. Many of these spectrum management techniques and business practices have been incorporated into AFMS over the past nine years. Spectrocan has marketed and customized AFMS to be deployed in South East Asia, South America and Africa. National regulatory agencies for Spectrum Management use systems like AFMS to keep records on all frequency allocations. These systems are database driven and are considered enterprise wide solutions encompassing data entry, record management, financial transaction management, and technical data management and analysis.
In the frequency engineering realm analytical systems have been used for more than a decade. These tools are part of the solution telecom companies employ when designing telecom infrastructure and applying for frequency allocations.
Spectrum regulators have only recently employed GIS as a means of speeding their application process in response to the growing demand for frequency allotments by telecom companies. More and more national regulators are focusing on the Technical Analysis and GIS components of Frequency Management systems. As a result, Spectrocanís AFMS product provides a robust cost effective solution to handle geographic information and perform the complicated EMC analysis required for technical approval.
As mentioned previously, frequency management systems have only recently incorporated GIS. The following is a list of the current challenges both regulators and telecom applicants face.
1) Regulators are not set-up to allow secure external access to information, therefore limiting applicants ability to assess their application against the national database.
2) Regulators use worst case propagation modeling there by limiting their ability to use natural and man made barriers to propagation and limiting the number of potential frequency allocations for a given area.
3) Telecomís use best case propagation modeling therefore submitting potentially conflicting supporting analysis to the national regulator.
4) Regulatorís and telecomís may not use the same map information for their assessments resulting in different analysis of frequency coverage.
5) Length of time required for interaction between regulators and telecoms penalizes revenue growth.
AFMS is used to manage the frequency application process, incorporate government policies, manage the technical analysis of new stations, the issuing of licenses, spectrum monitoring, and manage the financial transactions throughout the process.
To overcome the issues facing the industry and regulators, Spectrocan utilizes spatial information through the implementation of a new GIS Framework. The GIS Framework is an architecture that solves a specific requirement. In this case the requirement is to utilize spatial information and GIS processing for a more effective management of frequency allocations and take advantage of automated processes and imbed the functionality within the overall application workflow. The tools used in the GIS Framework are from Esriís suite of software in conjunction with an Oracle database.
The architecture for the GIS framework had to meet critical guidelines. First the Framework had to be extendable with each component being replaceable with minimal reconfiguration. Second, the Framework had to interface with the AFMS application architecture with as few points of contact as possible. Thirdly, the Framework had to be able to be deployed without AFMS to satisfy the needs of application design clients.
The resulting framework allows deployment of several different configurations of GIS data and applications. The GIS framework maintains only three points of contact with the AFMS application framework and these points are not critical to the frameworks operability. Finally the framework when deployed alone can serve as a Technical Analysis/Database/Information Query system and interface with existing client enterprise systems.
Critical to the success of the GIS Framework is the use of a component based architecture and maintaining open interfaces between major subsystems. To ensure a high degree of configuration of the framework each component reads configuration requirements from a configuration table. The workflow processes act according to the configuration information ensuring that spatial data is updated when required and access to different GIS functionality is available only if the corresponding components are implemented.
The GIS Framework contains the following major application components:
∑ Database Management
∑ Technical Analysis (TA-GIS)
∑ Enterprise Viewing (Enterprise GIS Viewer)
ArcSDE is the heart of the GIS framework of AFMS. Within the ArcSDE database the spatially referenced frequency assignment information forms a layer. Secure level views of the frequency assignments gives AFMS the ability to present station information based on the AFMS security level of the user. The ArcSDE layers house station transmission information such as location, station type, frequency assignment, and antenna direction.
Other layers stored in ArcSDE include planimetric map data, zoned information, and elevation data. The planimetric map data at a minimum of 1:25,000 provides an adequate base from which detailed maps are generated and realistic 3D visualization is available. Zoned information layers are derived in correlation with planimetric information. One example of zoned information is the coordination/notification zone along a countries border. If frequency assignments located within this coordination zone additional coordination with other countries is required before a license is issued. Finally elevation data is used to model terrain surfaces for use in visualization and enhanced propagation models.
Conversion of map data is done using the batch processing functionality of Feature Manipulation Engine (FME) by Safe Software. Through the use of batch macros digital map data is parsed and reconfigured into the geometry data structure required for the individual layers. This means that features represented in the source format are lines but polygons are required for the desired functionality of the GIS Framework, FME allows for this generation and loading of target data quickly and efficiently.
† Once data is bulk loaded management of the data becomes a critical issue. To ensure frequency assignment information is accurate an interface exists between the AFMS database and the ArcSDE database ensuring that whenever data is inserted, updated or deleted in the AFMS database the spatial geometry and attribute information for that frequency assignment are maintained in parallel and in real time in the ArcSDE database. Management of the base layer information is achieved through ArcView allowing minor edits to be performed.
ArcView , providing map display and query functions, allows users access to the technical analysis tools required to do both the telecom modeling using refined propagation models, or regulatory analysis using FreeSpace interference calculations. The advantage for RF engineers is the ability to analyze frequency configurations under the both a design environment and a regulatory environment thus reducing the potential for rejection of frequency applications. Also spectrum engineers have the tools available to evaluate frequency configurations using refined propagation models.
Spectrocan has integrated HNIT-Balticís Cellular Expert tool used by network designers to plan new wireless services. By integrating this tool and engaging spectrum management models, both the regulator and the telecom company can use the same set of functions and algorithms to design and approve new frequency assignments.
The TA-GIS application employs the 3D Analyst, and Spatial Analyst extensions for ArcView to give a full view experience of the analysis being performed. Spectrocan has built an interface from ArcSDE and AFMS tables to facilitate the creation of the ArcView workspaces required for the cellular planning tool.
The spectrum engineer launches the TA-GIS application from within AFMS by simply choosing a station on which to perform an analysis, declaring a radius within which to consider other frequencies, and a frequency offset value in MHz. The TA-GIS application dynamically finds all stations and map data matching the search criteria of distance and frequency separation, creates the workspace, and creates the elevation grid of the area. From the created workspace the spectrum engineer can then perform a technical analysis on the proposed frequency assignment using any of the supplied propagation models or user defined models. The spectrum engineer, once analysis is complete, returns to AFMS to accept of reject a frequency assignment.
The result of this automated approach is a streamlined activity to retrieve all of the information the spectrum manager requires to review the application, perform the technical assessment and approve the frequency assignment. The time saving through the use of TA-GIS is anywhere from 50%-90% compared to the tabular reports or the manual processes spectrum managers would have historically used.
ArcIMS, Esriís internet mapping platform, provides an opportunity to extend GIS capability beyond the hands to the spectrum engineer and into the regulatory organization as a whole. The Enterprise GIS Viewer is based on the HTML viewer of ArcIMS. Map data and frequency assignments are viewed and queried dynamically by different members of the organization. Each member of the organization has an associated security level access to frequency information and the Enterprise Viewer produces maps accordingly by showing only the appropriate secure information.
Whenever the status of a frequency assignment changes in AFMS, a procedure automatically updates the frequency assignment layer in ArcSDE and is therefore immediately viewable across the organization. Over sixty values are updated during this seamless background process. Changes to frequency allocation information initiates from AFMS, ensuring that data integrity of the license station values is maintained and managed through the main AFMS application.
Along with the ability of serving map information within the organization the GIS Framework ensures that data can be easily disseminated over the internet. The functionality of the Enterprise GIS Viewer can be configured to provide web access to frequency and map information applicants need. The external web interface allows users to query and download map and station information for infrastructure design to better anticipate potential frequency conflicts. The external dissemination of information by the regulator is also an additional revenue generator through payment for access to frequency information.
The Framework concept was deployed to ensure usability of the technology beyond the AFMS implementation. Through the use of data dictionaries in TA-GIS the technical analysis module can be deployed within telecom companies. Through the use of the Enterprise GIS Viewer, telecom companies can view and use frequency assignments to assist their designs. The final advantage is that applications can be added to and taken away without any adverse effects.
Through the deployment of the GIS Framework within a frequency management process several critical issues involving the regulator and the applicants are resolved.
1) Regulators, through the use of the Enterprise GIS Viewer, can give applicants secure external access to frequency allocations to use in the design of new infrastructure.
2) Regulators can use design system propagation models to evaluate interference possibilities prior to complex situations.
3) Applicants can use regulatory models for interference analysis to pre-validate their designs before submission.
4) Regulators will be able to serve map information to allow applicants to use the same terrain and building information that will be used for the regulatory analysis.
5) Through the increase in first time acceptance of applicant frequency assignments and the reduced time in the implementation of telecom infrastructure, the resulting improved time to market will increase revenue generation for both the regulator and the telecom applicant.
All of these opportunities exist with the implementation of the full GIS Framework. The modular nature of the framework allows both regulators and telecom applicants to overcome one challenge at a time and quickly take advantage of all the opportunities by adding the additional components.
Spatial Information plays a key role in the frequency management industry. The use of GIS tools and geographic data results in benefits to both applicants and regulators. Applicants are realizing the benefits of leveraging spatial data through savings in engineering costs, better technical analysis and shorter time to market. For regulators the benefits include a faster application evaluation process, enhanced wave propagation models improving quality of assessment, increased spectrum availability and increased revenues.
From their offices in Ottawa, Ontario, Spectrocan provides comprehensive spectrum management solutions to telecommunications regulators around the world. Spectrocan, through a transfer-of-technology agreement with Industry Canada has developed an enterprise solution dedicated to the administrative management of radio spectrum organisations. Along with implementations of their proprietary suite of products, the Automated Frequency Management System (AFMS), Spectrocan provides extensive consulting services focused on spectrum policy, spectrum regulation, training, and business process development.
Spectrocan has access to some of the most experienced and dependable multi-disciplinary subject matter experts in the consulting industry. To complement the delivery of spectrum management services, Spectrocan works with affiliate, AMEC Technologies Limited to provide project management, software engineering, technology consulting, web-enabling and application maintenance services. Both AMEC Technologies and Spectrocan draw, when required, from the experienced and well-qualified AMEC group of companies to complement their own capabilities.
Parent company, AMEC is a market leader in the United Kingdom, in France through associate company SPIE S.A. and now in North America through its merger with engineering, construction and technology services leader AGRA Inc. AMEC also has significant operations in South East Asia and Australia.
AMEC provides added value solutions and total life of asset support to clients in selected market sectors, including oil and gas, utilities, rail, mining, forest products healthcare, pharmaceuticals and transportation.† AMEC's shares are traded on the London Stock Exchange. AMECís website is found at www.amec.com.
AMEC Technologies is online at www.amec.com/technologies
Spectrocan's web site is found at www.spectrocan.com.