【应用手册】AN 610: Implementing Deterministic Latency for CPRI and OBSAI Protocols in Altera Devices
This application note describes how to implement deterministic latency for Common
Public Radio Interface (CPRI) and Open Base Station Architecture Initiative Reference
Point 3-01 (OBSAI RP3-01) protocols with transceivers in Stratix® IV, HardCopy® IV,
Arria® II GX, and Cyclone® IV devices. It also describes the transceiver configuration
and clocking scheme to implement deterministic latency. You can create your
proprietary CPRI, OBSAI RP3-01, or other interfaces requiring deterministic latency
designs based on the implementation descriptions in this application note.
The CPRI and OBSAI RP3-01 are point-to-point, high-speed serial interfaces in
wireless applications for connecting base station component and remote radio heads.
Figure 1 shows various CPRI topologies. Fundamentally, CPRI connects between a
radio equipment controller (REC) and radio equipment (RE) modules (in single-hop
connections). For high bandwidth, multiple REs can be chained to a single REC (in
multi-hop connections), with CPRI links between the RE modules. The REC port is
always the master port and the RE is the slave port for links between REC and RE.
For links between REs, the port nearest to REC is the master.an610.pdf