Universal digital card (UDC) for use as digital donor card or digital distribution card

1. A universal digital card (UDC) for use in a distributed antenna system (DAS), the UDC comprising:

an external digital interface to communicatively couple the UDC to an external communication link used to transmit and receive data in any of a plurality of different external interface formats; and

wherein the UDC is configured to:

receive data formatted according to any of the plurality of external interface formats from the external communication link via the external digital interface;

transmit data formatted according to any of the plurality of external interface formats over the external communication link via the external digital interface; and

wherein the UDC is configured to be selectively used either as:

a donor card to communicatively couple the node to one or more base station entities via the external digital interface; or

a distribution card to communicatively couple the node to one or more non-DAS nodes, hubs, switches, or remote radio heads or one or more other DAS nodes or access points.

2. The UDC of claim 1 , wherein the UDC is configured for use in a subrack of a node of the DAS;

wherein the UDC further comprises:

a backplane interface to communicatively couple the UDC to a backplane of the subrack, wherein the backplane is configured to communicate fronthaul data in a digital fronthaul interface format natively used in the DAS;

wherein the UDC is configured to:

convert the received data to the digital fronthaul interface format natively used in the DAS;

communicate the converted data over the backplane of the subrack via the backplane interface;

receive data formatted according to the digital fronthaul interface format natively used in the DAS from the backplane of the subrack via the backplane interface; and

convert the received data to any of the plurality of external interface formats.

3. The UDC of claim 2 , wherein the digital fronthaul interface format natively used in the DAS comprises a proprietary time-domain baseband in-phase and quadrature (IQ) fronthaul format.

4. The UDC of claim 3 , wherein the plurality of external interface formats comprises at least one of:

an Open Radio Access Network (O-RAN) fronthaul interface format that uses an Option 7-2 functional split;

a Common Public Radio Interface (CPRI) fronthaul interface format;

a compressed CPRI fronthaul interface format;

an evolved CPRI (eCPRI) fronthaul interface format;

an Institute of Electrical and Electronics Engineers (IEEE) 1914.3 Radio-over-Ethernet (ROE) interface format;

a functional application programming interface (FAPI) or a network FAPI (nFAPI) interface format; and

a proprietary frequency-domain baseband IQ fronthaul interface format configured for use over a switched Ethernet network.

5. The UDC of claim 2 , wherein the base station entities that the UDC is configured to couple the node to includes at least one of:

a baseband unit (BBU) or virtualized BBU (vBBU) configured to communicate over the external communication link using a Common Public Radio Interface (CPRI) fronthaul interface format or an evolved Common Public Radio Interface (eCPRI) interface format;

an Open Radio Access Network (O-RAN) Distributed Unit (O-DU) or virtualized O-DU (vDU) configured to communicate over the external communication link using an O-RAN fronthaul interface format; and

a small cell BBU (SC BBU) configured to communicate over the external communication link using a proprietary frequency-domain baseband IQ fronthaul interface format configured for use over a switched Ethernet network.

6. The UDC of claim 2 , wherein the one or more DAS nodes or access points that the UDC is configured to couple the node to includes one or more high-capacity DAS nodes or access point configured to communicate over the external communication link using a high-capacity transport interface format.

7. The UDC of claim 2 , wherein the one or more non-DAS nodes, hubs, or remote radio heads that the UDC is configured to couple the node to includes one or more:

small cell radio points configured to communicate over the external communication link using a proprietary frequency-domain baseband IQ fronthaul interface format configured for use over a switched Ethernet network;

Common Public Radio Interface (CPRI) remote radio heads configured to communicate over the external communication link using a CPRI fronthaul interface format;

evolved CPRI (eCPRI) remote radio heads configured to communicate over the external communication link using an eCPRI fronthaul interface format; and

Open Radio Access Network (O-RAN) Remote Units (O-RUs) configured to communicate over the external communication link using an O-RAN fronthaul interface format.

8. The UDC of claim 2 , wherein the node of the DAS comprises at least one of a central access node (CAN), a transport expansion node (TEN), and a wide-area integration node (WIN).

9. The UDC of claim 2 , wherein other types of donor cards and/or other types distribution cards are used in the subrack.

10. The UDC of claim 9 , wherein the other types of donor cards comprise at least one of: RF donor cards, and CPRI digital donor cards.

11. The UDC of claim 9 , wherein the other types of distribution cards comprise fiber distribution cards and copper twisted-pair distribution cards.

12. A node of a distributed antenna system (DAS) comprising:

a universal digital card (UDC) comprising:

an external digital interface to communicatively couple the UDC to an external communication link used to transmit and receive data in any of a plurality of different external interface formats; and

wherein the UDC is configured to:

receive data formatted according to any of the plurality of external interfaces formats from the external communication link via the external digital interface; and

transmit communicate the converted data formatted according to any of the plurality of external interface formats over the external communication link via the external digital interface; and

wherein the UDC is configured to be selectively used either as:

a donor card to communicatively couple the node to one or more base station entities via the external digital interface; or

a distribution card to communicatively couple the node to one or more non-DAS nodes, hubs, switches, or remote radio heads or one or more other DAS nodes or access points.

13. The node of claim 12 , wherein the node further comprises a subrack comprising a plurality of slots and a backplane;

wherein the UDC comprises:

a backplane interface to communicatively couple the UDC to the backplane of the subrack, wherein the backplane is configured to communicate fronthaul data in a digital fronthaul interface format natively used in the DAS;

wherein the UDC is configured to:

convert the received data to the digital fronthaul interface format natively used in the DAS;

communicate the converted data over the backplane of the subrack via the backplane interface;

receive data formatted according to the digital fronthaul interface format natively used in the DAS from the backplane of the subrack via the backplane interface;

and convert the received data to any of the plurality of external interface formats.

14. The node of claim 13 , wherein the digital fronthaul interface format natively used in the DAS comprises a proprietary time-domain baseband in-phase and quadrature (IQ) fronthaul format.

15. The node of claim 14 , wherein the plurality of external interface formats comprises at least one of:

an Open Radio Access Network (O-RAN) fronthaul interface format that uses an Option 7-2 functional split;

a Common Public Radio Interface (CPRI) fronthaul interface format;

a compressed CPRI fronthaul interface format;

an evolved CPRI (eCPRI) fronthaul interface format;

an Institute of Electrical and Electronics Engineers (IEEE) 1914.3 Radio-over-Ethernet (ROE) interface format;

a functional application programming interface (FAPI) or a network FAPI (nFAPI) interface format; and

a proprietary frequency-domain baseband IQ fronthaul interface format configured for use over a switched Ethernet network.

16. The node of claim 13 , wherein the base station entities that the UDC is configured to couple the node to includes at least one of:

a baseband unit (BBU) or virtualized BBU (vBBU) configured to communicate over the external communication link using a Common Public Radio Interface (CPRI) fronthaul interface format or an evolved Common Public Radio Interface (eCPRI) interface format;

an Open Radio Access Network (O-RAN) Distributed Unit (O-DU) or virtualized O-DU (vDU) configured to communicate over the external communication link using an O-RAN fronthaul interface format; and

a small cell BBU (SC BBU) configured to communicate over the external communication link using a proprietary frequency-domain baseband IQ fronthaul interface format configured for use over a switched Ethernet network.

17. The node of claim 13 , wherein the one or more DAS nodes or access points that the UDC is configured to couple the node to includes one or more high-capacity DAS nodes or access point configured to communicate over the external communication link using a high-capacity transport interface format.

18. The node of claim 13 , wherein the one or more non-DAS nodes, hubs, or remote radio heads that the UDC is configured to couple the node to includes one or more:

small cell radio points configured to communicate over the external communication link using a proprietary frequency-domain baseband IQ fronthaul interface format configured for use over a switched Ethernet network;

Common Public Radio Interface (CPRI) remote radio heads configured to communicate over the external communication link using a CPRI fronthaul interface format;

evolved CPRI (eCPRI) remote radio heads configured to communicate over the external communication link using an eCPRI fronthaul interface format; and

Open Radio Access Network (O-RAN) Remote Units (O-RUs) configured to communicate over the external communication link using an O-RAN fronthaul interface format.

19. The node of claim 13 , wherein the node of the DAS comprises at least one of a central access node (CAN), a transport expansion node (TEN), and a wide-area integration node (WIN).

20. The node of claim 13 , wherein other types of donor cards and/or other types distribution cards are used in the subrack.

21. The node of claim 20 , wherein the other types of donor cards comprise at least one of: RF donor cards, and CPRI digital donor cards.

22. The node of claim 20 , wherein the other types of distribution cards comprise fiber distribution cards and copper twisted-pair distribution cards.