White Papers

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21 | Whitepaper – Exploring Computing Platforms for Radio Access
Networks
6 Platform Architectures
6.1 Flexible Architectures for the Network Edge
Using the 5G NR network architecture split, Figure 23 can be used to conceptualize server
platforms that utilize FPGA peripherals. In the DU area, the FPGA will be used, as
demonstrated, for look aside acceleration such as 4G/5G FEC. In the CU & 5G CN areas,
although not the primary subject of this paper, the FPGA can be used to accelerate machine
learning operations, video transcoding, and other tasks in support of Multi-access Edge
Computing. The FPGA based solution can be paired with any IA (Intel® architecture) based
CPUs, such as the Intel® Xeon® Scalable processor product line available in PowerEdge
Servers. Intel offers FPGA and eASIC
16
based solutions to accommodate the HW acceleration
needs. FPGA provides great flexibility through its ability to be reprogrammed, while the eASIC
based solution is a fixed function device aiming to bridge the performance gap between an
ASIC and FPGA implementations.
Figure 23: Hardware Accelerator Offload Possibilities
Another emerging application in this arena is indoor wireless. As the trend for more rich and
numerous mobile applications expands, the buildout of more (and smaller) cells is inevitable. To
implement the controllers for the increasing amount of radio equipment, standard datacenter
racks can be deployed indoors. A small computing cluster can implement all the functions
described, and where applicable, FPGA peripherals can be used for direct radio interfaces,
including legacy interfaces that use CPRI.
6.2 Platform Example
More detailed block diagrams of the CU/DU/Edge solutions are provided in this section. An Intel
® Xeon® Scalable processor-based solution utilizing up to 8 DDR channels of host memory is
shown in Figure 24. A FPGA is placed on a PCIe card to provide various acceleration
functionality depending on its location in the network. The FPGA based PCIe card is connected
via 16 PCIe lanes for acceleration. Ethernet capability is provided by the NIC PCIe cards.