2.1 RBBs Each RBB defines a unique way of combining RUs or RRUs in one sector with connections to DUs and the antenna system.
RBBs are named as follows: RBB[Tx][Rx]_[C][V], where: Tx Number of Transmitter (TX) branches Rx
Number of Receiver (RX) branches (excluding co-siting RX ports)
C
Number of CPRI links
V
Version
Example: RBB12_1A 2.1.1
One TX branch Two RX branches One CPRI link between DU and RU or RRU Version A
RBB10_1A
RBB10_1A is used for sectors with one TX branch, two external RX branches, and one CPRI connection. Figure 2 shows the RBB10_1A block diagram.
Figure 2 2.1.2
RBB10_1A Block Diagram
RBB11_1A
RBB11_1A is used for sectors with one TX branch, two RX branches, of which one is an external RX branch for antenna sharing, and one CPRI connection. Figure 3 shows the RBB11_1A block diagram.
Figure 3 2.1.3
RBB11_1A Block Diagram
RBB12_1A
RBB12_1A is used for sectors with one TX branch, two RX branches, and one CPRI connection. Figure 4 shows the RBB12_1A block diagram.
Figure 4 2.1.4
RBB12_1A Block Diagram
RBB22_1A
RBB22_1A is used for sectors with two TX branches, two RX branches, and one CPRI connection. There is an analog cross-connection between the RUs or RRUs. Figure 5 shows the RBB22_1A block diagram.
Figure 5 2.1.5
RBB22_1A Block Diagram
RBB22_1B
RBB22_1B is used for sectors with two TX branches, two RX branches, and one CPRI connection. Note:
It is also possible to use only one TX branch.
Figure 6 shows the RBB22_1B block diagram.
Figure 6 2.1.6
RBB22_1B Block Diagram
RBB22_1C
RBB22_1C is used for sectors with two TX branches, two RX branches, and one CPRI connections. There is a digital cross-connection between the RUs or RRUs. Figure 7 shows the RBB22_1C block diagram.
Figure 7 2.1.7
RBB22_1C Block Diagram
RBB12_2A
RBB12_2A is used for sectors with one TX branch, two RX branches, and two CPRI connection. This RBB is used for Mixed Mode with no CPRI sharing. Figure 8 shows the RBB12_2A block diagram.
Figure 8
RBB12_2A Block Diagram
2.1.8
RBB22_2A
RBB22_2A is used for sectors with two TX branches, two RX branches, and two CPRI connections. This RBB uses a digital RX cross-connection. Figure 9 shows the RBB22_2A block diagram.
Figure 9 2.1.9
RBB22_2A Block Diagram
RBB22_2B
RBB22_2B is used for sectors with two TX branches, two RX branches, and two CPRI connections. There is an analog cross-connection between the RUs or RRUs. Figure 10 shows the RBB22_2B block diagram.
Figure 10 2.1.10
RBB22_2B Block Diagram
RBB22_2E
RBB22_2B is used for sectors with two TX branches, two RX branches, and two CPRI connections. This RBB is used for Cross-Sector Antenna Sharing Redundancy. Each RRU can serve two different sectors. Figure 11 shows the RBB22_2E block diagram.
Figure 11 2.1.11
RBB22_2E Block Diagram
RBB22_4B
RBB22_4B is used for sectors with two TX branches, two RX branches, and four CPRI connections. This RBB uses an analog RX cross-connection. This RBB is used for Mixed Mode with no CPRI sharing. Figure 12 shows the RBB22_4B block diagram.
Figure 12
RBB22_4B Block Diagram
2.1.12
RBB24_2A
RBB24_2A is used for sectors with two TX branches, four RX branches, and two CPRI connections. This RBB uses a digital RX cross-connection. Figure 13 shows the RBB24_2A block diagram.
Figure 13 2.1.13
RBB24_2A Block Diagram
RBB32_3A
RBB32_3A is used for sectors with three TX branches, two RX branches, and three CPRI connections. There is an analog cross-connection between the RUs or RRUs. Figure 14 shows the RBB32_3A block diagram.
Figure 14 2.1.14
RBB32_3A Block Diagram
RBB32_3B
RBB32_3B is used for sectors with three TX branches, two RX branches and one external RX cross connection, and three CPRI connections. There is an analog cross-connection between the RUs or RRUs. Figure 15 shows the RBB32_3B block diagram.
Figure 15 2.1.15
RBB32_3B Block Diagram
RBB43_4A
RBB43_4A is used for sectors with four TX branches, three RX branches, and four CPRI connections. There is an analog cross-connection between the RUs or RRUs. Figure 16 shows the RBB43_4A block diagram.
Figure 16
RBB43_4A Block Diagram
