RF power amplifiers and antennas for satellite and cellular telecommunications – The chronicles by Yole SystemPlus

5G cellular communication is seeing the advent of massive MIMO (Multiple-Input Multiple-Output) AAUs (active antenna units) to significantly improve coverage and throughput. Unlike 4G base stations which require three distinct units – antennas, RRU (remote radio unit), and BBU (Baseband Unit) – active antenna systems include only two units, the antennas and RRU being merged. According to Yole Intelligence, five major OEMs are leading the BTS (Base Transceiver Station) market: Nokia, Huawei, Ericsson, Samsung, and ZTE. The BTS RF front-end market expects growth in revenue from US$3.2 billion to US$3.8 billion (CAGR 2022-2028 of +4%) but is much more fragmented.

LEO (low Earth orbit) satellites support the transformation of the global connectivity landscape by providing global coverage and enabling communication in regions where terrestrial infrastructure is limited or nonexistent. This highly competitive industry attracts big names such as SpaceX, OneWeb, and Amazon, but also many smaller companies.

Yole SystemPlus, has addressed the topic of RF amplifiers and antennas in satellite and cellular telecommunications, with several reports on technology, processes, and costs, especially: Starlink Gen 2 Chipset, ZTE 5G AAU Chipset, and Ericsson 5G Integrated Radio Unit AIR6488 Chipset.

Yole SystemPlus and Yole Intelligence are part of Yole Group.

In addition to these detailed reverse engineering & costing analyses, Yole SystemPlus releases a new type of products, fully part of the Teardown Tracks family. The Telecom Teardown Tracks propose the dismantling of over 15 SG telecom systems selecting the latest and most disruptive ones such as SG Baseband Units, Active Antenna Units and CPEs. These products issue from a fruitful collaboration between the Japanese company, Fomalhaut Techno Solutions, and Yole SystemPlus.

Satellite communication: remarkable Starlink Gen 2 system

According to the Starlink Gen 2 Chipset report, remarkable is the first word that comes to mind when talking about the Starlink Gen 2 system (user terminal).The Starlink first generation constellation  which began launching in 2019 orbits at about 550 km from the ground, while GEO (geostationary orbit) satellites orbit at 36,000 km. As of May 2023, Starlink has launched about 4,400 LEO satellites. Starlink provides broadband internet which supports higher data rates with lower latency than traditional satellite internet broadband.

Starlink communicates with ground transceivers that use traditional X-, Ku- and Ka- microwave bands, which operate in the 8-12, 12-18, and 26.5-49 GHz bands, respectively.  Looking inside the Gen2 Starlink ‘dishy’ ground transceiver, remarkable is also the appropriate word according to Yole SystemPlus. The various chips – DSP (digital signal processing), DRAM, GPS antenna, FEM (Front End Module), and DBF (Digital Beamforming) – of the PCB (Printed Circuit Board) were identified and physically analyzed. The system comprises six layers, including the radome, the PCB, two plastic separators, and two sheets of printed patch antennas (each patch having a total of 1016 phased array antenna elements). The main point to note is that the silver patches are printed on very thin plastic sheets which helps to reduce the system’s weight. A total of 508 FEMs were observed, suggesting that each FEM is linked to two antenna elements.

Cellular communication: active antenna units for 5G massive MIMO

The Ericsson AIR6488 and ZTE A9611A 5G AAUs were analyzed. The reports also issued from the partnership between Fomalhaut Techno Solutions and Yole SystemPlus. In addition to the systems’ analysis developed by Fomalhaut Techno Solutions, Yole SystemPlus completed the analysis by performing technology and cost analyses of the components as well as attempting to establish the system functionality basing on the physical analysis.

The two systems comprise four PCBs: the RF main board or RF PCB, the CPU (central processing unit) PCB, the power PCB, and the antenna PCB. Both active antennas enable beamforming through Massive MIMO technology. They use multiple physical antenna elements – 64 for Ericsson’s AAU and 96 for ZTE’s – to concentrate signals into narrow beams for significant 5G capacity improvement and interference reduction. They operate in the FR1 frequency range, which includes sub-6 GHz frequency bands.

The RF board integrates a power amplifier made by NXP Semiconductors in one case and Ampleon in the other, both based on LDMOS (laterally-diffused metal-oxide semiconductor), a longstanding process used for base station transceivers. However, as technology moves up to 5G frequencies, the next five years should see GaN gaining momentum, according to Yole Intelligence, gradually sidelining Si-based technology. Whether on Si or SiC, GaN HEMT (High-Electron Mobility Transistor), with its high-power density, addresses most of the SWaP-C issues (size, weight, power consumption, and cost), still leaving at this time the cost advantage to LDMOS. As we move further into the frequency range (5G mmWave), GaN may have to compete with other technologies, such as SiGe, RFSOI, CMOS, and InP. The GaN on SiC trend is confirmed by the recent analyses carried out by Yole SystemPlus on several RF power solutions for telecom infrastructures. GaN on Si remains at the announcement level. Infineon is claiming a ‘coming soon’ GaN on Si power amplifier module, while ST Microelectronics, Macom, and Ommic are paying close attention to this technology. 

About the authors

Alfred Mudonhi, Ph.D., is a Technology and Cost Analyst at Yole SystemPlus, part of Yole Group. Alfred’s mission at Yole SystemPlus involves regular interactions and exchanges with the laboratory teams in order to produce reverse engineering and costing reports in the Radio Frequency field. He is tasked with providing an in-depth understanding of the cost of the technologies selected by the leading semiconductor companies as well as the ecosystem around a device. Alfred holds a master’s degree in telecommunications engineering from the University of Trento, Italy and a doctorate degree in Engineering Sciences and Technology from the Université catholique de Louvain (UCLouvain), Belgium. Prior to Yole SystemPlus, Alfred worked as an R&D engineer at CEA-Leti, Grenoble, France.

Minatake Kashio is a founder and CEO of Fomalhaut Techno Solutions, processioned in product teardown and component cost estimation over 2000 items up to date. Minatake started his careers at Japanese government in 1997 followed by moving to Canadian Federal Government affiliate organization in 2000 before starting Fomalhaut in 2008. He is an inventor of location-based information delivery system to mobile terminals, patented as JP4729666 in 20111. Minatake has a bachelor in foreign language study from the Sophia University, in Tokyo, Japan in 1997. Minatake is an active member of IEEE and U.S. Naval Institute.