This document provides a comprehensive comparison of five digital sound broadcasting systems for satellite and terrestrial delivery, as detailed in the International Telecommunication Union (ITU) Radiocommunication Sector’s Recommendation BO.1130-4. The analysis evaluates the technical characteristics and performance of Digital System A, Digital System B, Digital System Ds, Digital System Dh, and Digital System E. The purpose of this analysis is to provide a clear, objective assessment of each system’s architecture and capabilities to assist engineers, network planners, and policymakers in making informed implementation decisions for new satellite and terrestrial broadcasting services.

The five systems under review represent distinct engineering philosophies and have been field-tested to validate their performance. They are:

• Digital System A (Eureka 147 DAB)
• Digital System B
• Digital System Ds (WorldSpace, satellite component)
• Digital System Dh (Hybrid satellite/terrestrial WorldSpace)
• Digital System E (ARIB)

This document will begin with high-level overviews of each system’s design and intended application. It will then proceed to a detailed thematic comparison of key performance metrics, including audio coding, spectral efficiency, and robustness in challenging reception environments. Finally, it will consolidate these findings to assess each system’s suitability for different reception scenarios—vehicular, portable, and fixed—providing a foundational basis for strategic technology selection.