In recent years, there has been a massive uptick in the data consumption among mobile broadband subscribers in many major African markets, such as Nigeria and Kenya.
By Chafic Traboulsi, vice-president and head of networks at Ericsson Middle East and Africa
Meeting the capacity needs coming from this data growth, presents a unique set of challenges and opportunities for the communication service providers and their networks.
Traditional microwave links have been a cornerstone of network infrastructure globally, as well as in Africa. However, as the volume of data carried by radio base stations continues to surge, the need for increased microwave link capacity has become more critical than ever. In fact, due to the tree-like structure of the microwave links, the capacity demand on the microwave links increases faster than that of the radio access networks.
In this article, we focus on how high-capacity microwave solutions, in both short and long distances, can address the escalating capacity requirements of mobile networks in many African countries.
E-band: High capacity at short distances
The E-band spectrum (70/80GHz) is essential for supporting the ever-increasing requirements from the RAN for 5G and beyond. It offers fiber-like capacities and can be rolled out fast and efficiently.
70/80GHz spectrum has been allocated to E-band microwave use by regulators in several African countries, for instance by both Communications Authority of Kenya (CA) and Nigerian Communications Commission (NCC). Operators in both these countries are enjoying the benefits of E-band transmission links such as fast time to market, lower TCO and latency compared to fibre.
To get the longest distance, lowest antenna size and highest capacity, the most important design parameter to consider is the E-band microwave system gain. This parameter is the sum of output power and the receiver sensitivity. The higher the system gain, the better. Ericsson’s E-band microwave solution has the highest system gain in the industry.
This is particularly important for African countries where heavy seasonal rains can occur. The more rain, the worse it is for E-band links, and a high system gain is vital in these conditions.
There is yet another degree of freedom for E-band links which is called the link availability. While in a normal short haul link we aim for a 99.999% link availability, we can significantly boost the capacity over extended distances if we drop the availability to 99.99%, with no effect on user experience, where a significant proportion of mobile backhaul traffic is constituted by packet-based data. We can also further improve link availability by using a traditional band along with the E-band link.
Ericsson calls this Multi-band Booster configuration. In such configurations, both frequencies can be combined using just one dual-band antenna which minimizes the number of antennas on the mast.
Lowering energy consumption is a key priority for many of the communications service providers in Africa, for both cost and emission reasons. Ericsson’s E-band solution has the lowest energy consumption and size pair in the industry. Along with innovations like Sway Compensation Antenna and Ericsson Transport Automation Controller, it is possible to maximize availability and minimize operations and support efforts.
Long Haul: High capacity at long distances
Long haul microwave links are ideal for high capacities at longer distances, and fit well with the needs to connect rural areas in Africa, and are also frequently used to closing fiber rings, providing link protection and island coverage. When the need is 2-10Gbps at distances of 10-120km, long haul link solutions are a good match as they can deliver high capacity at long distance. Many of the quite long-distance microwave links where the expected capacity to be carried is relatively low, can easily be served with short haul microwave solutions as well.
Modern microwave long haul links operate at 5-13GHz frequency range. The lower the frequency, the longer the RF signal’s reach. By using multiple channels and multiple frequency bands in combination with adaptive modulation and layer 1 (L1) radio-link bonding, it is possible to reach the targeted capacity and to meet the service-availability needs with long haul microwave.
As mobile data consumption continues its exponential growth in the countries of Africa, addressing capacity demands is imperative. Microwave technology, including E-band and long haul solutions, offers a robust toolkit to ensure network scalability, performance, and availability. From the high-capacity, short-distance advantages of E-band links to the long-distance prowess of long haul solutions, Ericsson’s innovations are poised to shape the future of mobile networks in Africa, driving connectivity, bridging gaps, and enabling the digital revolution.