1 Introduction

Satellite communications are entering a new phase of growth, driven by the convergence of terrestrial cellular networks and non-terrestrial networks (NTN). While traditional satellite services have relied largely on proprietary technologies and dedicated terminals, the emergence of large low earth orbit (LEO) constellations, lower launch costs, software-defined payloads and electronically steerable antennas enable satellite connectivity on an unprecedented scale.

One of the most significant market trends is the rapid emergence of satellite direct-to-device (D2D) and Internet of Things (IoT) connectivity. Since the early demonstrations of direct satellite connectivity to conventional mobile phone in 2020, satellite D2D/IoT technology has rapidly progressed toward commercial deployment, with significant market expansion expected through 2030. 3GPP NTN standardization is bringing satellite communications into the cellular ecosystem, while regulatory frameworks such as supplemental coverage from space (SCS) are enabling satellites to complement terrestrial mobile networks using cellular spectrum. Together with traditional mobile satellite service (MSS) spectrum, these developments create opportunities to extend connectivity directly to smartphones and low-power IoT devices in rural, remote, and underserved areas without requiring specialized satellite terminals.

These market trends are also reshaping satellite radio technology. A satellite communications system typically includes three type of links: service links, feeder links and inter-satellite links, as shown in Figure 1-1. The users receive satellite service (text, voice, or broadband internet) through service links which connect the user terminals (dedicated, cellphone, or IoT devices) to the satellite. The ground station (gateway), serving as the primary aggregation point for all user traffic entering and leaving the satellite network, connects the satellite through the feeder link, and the gateway in turn interfaces with the back-end data network. Serving different purposes, the radio design for service link and feeder link can be different.

In this white paper, we dive into the challenges faced by D2D/IoT satellite communication payload design and show how the TI AFE8030 enables a low-power, compact, versatile and high-performance Satcom payload radio design for D2D/IoT service link.