Dedicating 28GHz spectrum band to satellite services: Africa
May 5, 2022
The African continent has a large coverage gap of about 300 million people, representing about 22% of the total population. Countries with significant unserved populations include Nigeria, the Democratic Republic of Congo (DRC), Sudan, Tanzania, Niger, Ethiopia and Mozambique. These countries have large populations beyond urban areas with many communities located in difficult topography where it is economically unviable to lay terrestrial infrastructure. Assuming a gradual mobile coverage increase over a ten-year period into these unserved communities, we estimate that the demand will exceed 500Gbit/s by 2026 and exceed 4Tbit/s by 2031.
Satellite offers a future-proof solution for connectivity beyond urban areas in the region
Terrestrial microwave links used beyond urban areas typically use frequencies in the range of 5‑42GHz as these can support distances between 5-60km. However, these frequencies do not have sufficient capacity to meet the expected throughput of 5G cell sites and consumer data growth. As such, many communities in the African region will be left behind with limited network performance due to the terrestrial microwave bottleneck.
Satellite provides links for mobile and broadband services, and access and satellite-powered connectivity for broadband services in underserved / unserved areas where populations do not have access to the same level of broadband available in urban areas.
Satellite is an affordable option for unserved and underserved communities of Africa
Our scenario analysis of a hypothetical African operator found that satellite is more cost-effective than 5G for providing access and backhaul in underserved / unserved areas, with:
- satellite-powered links instead of terrestrial microwave for mobile and broadband services
- access and backhaul for broadband services.
As these underserved / unserved areas are population clusters with lower density (around 50 inhabitants per square kilometre) located more than 70km from the closest urban centre or traffic aggregation node, the scenarios are relevant for most unserved and underserved communities in Africa.
Optimising spectrum allocation for economic growth
The 28GHz spectrum band (27.5-29.5GHz) is widely used by satellite operators to provide global fixed and mobile satellite broadband services. Deviating from the globally agreed spectrum allocations by wholly or partially repurposing the 28GHz band for 5G / mmWave may precipitate adverse impacts (technical and economic), as countries seek to expand ubiquitous broadband access across land, sea and air with investments in Ultra High Throughput Satellites.
Economic benefits of 5G in mmWave are likely to be representative of the use cases that require localised high-capacity coverage. Few, if any, benefits of 5G mmWave are expected in underserved or unserved areas. This has significant implications for governments seeking to encourage economic growth in some targeted areas or to reduce the digital divide between communities. For Africa this issue is crucial as about 55% of its total 1.37 billion inhabitants live outside densely populated areas.