Building ARCS: Modernizing Amateur Radio Frequency Coordination

From Repeater Coordination Software to a Complete Engineering Platform

ARCS, the Amateur Radio Coordination System, began with a simple objective: modernize repeater coordination.

For decades, coordination organizations have relied on spreadsheets, email chains, paper records, and manually maintained databases to process applications and manage frequency records. While these methods served the amateur radio community well, they often required substantial volunteer effort and countless hours of administrative work.

ARCS was developed to bring those workflows into a modern, integrated platform while preserving the engineering principles that make effective frequency coordination possible.

What started as an application management system quickly evolved into a comprehensive coordination ecosystem capable of supporting nearly every aspect of the coordination process.

Today, ARCS combines engineering analysis, FCC integration, workflow automation, records management, mapping, reporting, and public directory services into a single cloud-hosted platform designed specifically for amateur radio frequency coordinators.

The Challenge of Modern Frequency Coordination

Frequency coordination is far more complex than assigning channels and maintaining a database.

Every application requires technical review, record validation, interference analysis, engineering evaluation, documentation, and ongoing lifecycle management. Coordinators must balance spectrum efficiency, system coverage, and potential interference while maintaining accurate records that may span decades.

As coordination databases grow, so does the complexity of managing them.

A single coordination request may involve:

• Multiple repeater sites
• Shared infrastructure
• Linked systems
• FCC license validation
• Antenna system analysis
• Terrain studies
• Coverage prediction
• Interference investigations
• Historical coordination records
• Supporting documentation

Traditionally, much of this information has been gathered manually from multiple sources. ARCS was designed to centralize these activities and provide coordinators with the information they need in minutes rather than days.

Engineering at the Core

Unlike many record management systems, ARCS was built around engineering analysis from the beginning.

The platform automates the collection and calculation of technical data while ensuring coordinators retain full control over final coordination decisions. When an application is submitted, ARCS gathers engineering data, performs calculations, analyzes coverage, and generates reports for review.

Key engineering capabilities include:

• Automatic ERP calculations
• Automatic HAAT calculations
• Automatic AMSL elevation determination
• GPS-based site selection and mapping
• Terrain analysis
• Coverage prediction modeling
• Longley-Rice propagation analysis
• Signal path analysis
• Interference detection
• Frequency conflict evaluation
• NTIA-based interference scoring
• Engineering report generation

Rather than relying solely on geographic spacing or frequency separation, ARCS analyzes real-world propagation factors to provide a more complete picture of potential system interactions. This allows coordinators to make informed decisions based on engineering data rather than assumptions.

Automated FCC Data Integration

One of the most time-consuming aspects of coordination management is validating license information and maintaining accurate records.

ARCS integrates directly with FCC systems, providing automated access to:

• FCC Universal Licensing System (ULS) records
• FCC Antenna Structure Registration (ASR) records
• License status information
• Expiration monitoring
• Ownership validation
• Callsign verification

Instead of manually searching multiple databases, coordinators can access licensing and ownership information directly within the workflow. This improves data accuracy while significantly reducing administrative overhead.

Intelligent Interference Analysis

Interference management is one of the most critical responsibilities of any coordination organization. ARCS includes an advanced interference detection engine designed to identify potential conflicts before they become operational issues.

The platform evaluates:

• Co-channel conflicts
• Adjacent-channel conflicts
• Signal overlap
• Coverage overlap
• ERP relationships
• Antenna height considerations
• Terrain shielding
• Path-specific propagation characteristics

Using Longley-Rice modeling and NTIA-based analysis methodologies, ARCS identifies situations that warrant additional review and provides coordinators with detailed engineering data to support decision-making. Rather than replacing engineering judgment, the system enhances visibility into potential issues before a frequency assignment is made.

Streamlining the Application Process

Modern users expect digital services and real-time visibility into the status of their requests.

ARCS provides a self-service portal that allows repeater owners, trustees, and applicants to manage the entire coordination process electronically.

Users can:

• Submit new coordination requests
• Request modifications
• Upload supporting documentation
• View application status
• Review engineering reports
• Manage ownership information
• Track renewals
• Communicate directly with coordinators

This creates a more transparent process while reducing reliance on phone calls, email exchanges, and manual record updates.

Digital Records Management

A coordination database represents decades of institutional knowledge. Preserving, protecting, and organizing that information is critical for any coordination body.

ARCS provides centralized records management for:

• Coordinated systems
• Site locations
• Engineering studies
• Coverage maps
• Coordination certificates
• Ownership records
• Application history
• Modification requests
• Interference complaints
• Compliance tracking
• Supporting documentation

Every significant action is captured within a detailed audit trail, helping preserve historical records while improving accountability and transparency.

A Living Repeater Directory

Most repeater directories require separate maintenance from coordination records. ARCS takes a different approach by building the public directory directly from the coordination database.

Because directory information is generated from the same authoritative records used by coordinators, listings remain current without requiring duplicate data entry.

Users can search by:

• Callsign
• Frequency
• Location
• County
• State
• Operating mode
• Network affiliation
• Geographic proximity

The result is a continuously updated directory that reflects real-world coordination records and provides reliable information to the amateur radio community.

Built for the Future

Scalability, reliability, and security were key design requirements throughout the development of ARCS.

The platform is hosted on Microsoft Azure, providing enterprise-grade cloud infrastructure designed to support growth and long-term operational requirements.

This architecture supports:

• High availability
• Scalable storage
• Geographic redundancy
• Secure authentication
• Automated backups
• Future service expansion

Whether supporting a single coordination organization or multiple groups across multiple states, ARCS is designed to scale as operational needs evolve.

More Than Coordination Software

ARCS is more than an application processing platform. It is a comprehensive coordination ecosystem that combines engineering analysis, FCC integration, digital records management, workflow automation, interference analysis, mapping, reporting, and public directory services into a unified solution.

Tasks that once required multiple software packages, GIS tools, engineering applications, spreadsheets, and manual processes can now be performed within a single platform.

The goal has never been to replace the frequency coordinator.

The goal is to provide coordinators with better data, more efficient workflows, and powerful engineering tools that allow them to spend less time managing records and more time managing spectrum.

As amateur radio continues to evolve, ARCS represents a modern approach to frequency coordination that combines engineering precision, operational efficiency, and cloud-based scalability in a platform built specifically for the needs of today’s coordination organizations.