Link auto-negotiation between a radio equipment controller (REC) and radio equipment (RE) in an ethernet-based fronthaul network

Patent metadata

Field	Value
Publication number	US-11228991-B2
Application number	US-201916435946-A
Country	US
Kind code	B2
Filing date	Jun 10, 2019
Priority date	Feb 1, 2019
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

Techniques that provide link auto-negotiation between a radio equipment controller (REC) and a radio equipment (RE) are described herein. In one embodiment, a method includes performing, by a proxy master, a Common Public Radio Interface (CPRI) Layer 1 (L1) link auto-negotiation with a RE to achieve a L1 synchronization between the proxy master and the RE at a link bit rate; communicating the link bit rate from the proxy master to a proxy slave; performing, by the proxy slave, a CPRI L1 link auto-negotiation with a REC to determine whether a L1 synchronization between the proxy slave and the REC is achieved, wherein if the L1 synchronization is achieved, the link bit rate is a common matching link bit rate achieved; and upon the common matching link bit rate being achieved, establishing a CPRI link between the REC and the RE using the common matching link bit rate.

First claim

What is claimed is:

1. A method comprising:
(a) performing, by a proxy master, a Common Public Radio Interface (CPRI) Layer 1 (L1) link auto-negotiation with a radio equipment to achieve a L1 synchronization between the proxy master and the radio equipment at a link bit rate;
(b) communicating the link bit rate from the proxy master to a proxy slave, wherein the communicating is performed via an Ethernet network;
(c) performing, by the proxy slave, a CPRI L1 link auto-negotiation with a radio equipment controller to determine whether a L1 synchronization between the proxy slave and the radio equipment controller is achieved using the link bit rate received from the proxy master;
(d) based on determining that the L1 synchronization between the proxy slave and the radio equipment controller is not achieved using the link bit rate, communicating an indication from the proxy slave to the proxy master via the Ethernet network that the L1 synchronization between the proxy slave and the radio equipment controller was not achieved and repeating (a), (b), and (c) using a plurality of other link bit rates until a common matching link bit rate is achieved among the radio equipment controller, the proxy slave, the proxy master, and the radio equipment; and
(e) upon the common matching link bit rate being achieved, establishing a CPRI link between the radio equipment controller and the radio equipment using the common matching link bit rate.

2. The method of claim 1 , wherein communicating the indication from the proxy slave to the proxy master further comprises:
communicating the indication from the proxy slave to the proxy master using an out-of-band control channel between the proxy slave and the proxy master.

3. The method of claim 1 , wherein communicating the link bit rate from the proxy master to a proxy slave further comprises:
communicating the link bit rate from the proxy master to the proxy slave using an out-of-band control channel between the proxy master and the proxy slave.

4. The method of claim 1 , wherein performing the CPRI L1 link auto-negotiation with the radio equipment by the proxy master further comprises:
resetting a CPRI link between the proxy master and the radio equipment after the L1 synchronization between the proxy master and the radio equipment is achieved.

5. The method of claim 1 , wherein performing the CPRI L1 link auto-negotiation with the radio equipment controller by the proxy slave further comprises:
determining, by the proxy slave, whether a hyper frame number synchronization between the proxy slave and the radio equipment controller is achieved using the link bit rate for a CPRI bit stream received from the radio equipment controller at the link bit rate;
transmitting, by the proxy slave, a CPRI bit stream towards the radio equipment controller using only the link bit rate received from the proxy master upon determining the hyper frame number synchronization; and
stopping the transmitting by the proxy slave after 10 hyper frames.

6. The method of claim 1 , wherein based on determining that the L1 synchronization between the proxy slave and the radio equipment controller is achieved using the link bit rate, the method further comprising:
communicating an indication from the proxy slave to the proxy master to allow CPRI link auto-negotiation operations to be performed between the radio equipment controller and the radio equipment to establish the CPRI link between the radio equipment controller and the radio equipment using the common matching link bit rate while the proxy master and the proxy master slave perform passive link monitoring operations, mapping operations, and de-mapping operations.

7. The method of claim 6 , wherein the passive link monitoring operations comprise:
monitoring, by the proxy master and the proxy slave, for CPRI LI link faults or a CPRI link reset; and
based on detecting a CPRI L1 link fault or a CPRI link reset, repeating (a), (b), and (c) until the common matching link bit rate is known among the radio equipment controller, the proxy slave, the proxy master, and the radio equipment.

8. A plurality of non-transitory computer readable storage media encoded with instructions that, when executed by a plurality of processors, cause the plurality of processors to perform operations, comprising:
(a) performing, by a proxy master, a Common Public Radio Interface (CPRI) Layer 1 (L1) link auto-negotiation with a radio equipment to achieve a L1 synchronization between the proxy master and the radio equipment at a link bit rate;
(b) communicating the link bit rate from the proxy master to a proxy slave, wherein the communicating is performed via an Ethernet network;
(c) performing, by the proxy slave, a CPRI L1 link auto-negotiation with a radio equipment controller to determine whether a L1 synchronization between the proxy slave and the radio equipment controller is achieved using the link bit rate received from the proxy master;
(d) based on determining that the L1 synchronization between the proxy slave and the radio equipment controller is not achieved using the link bit rate, communicating an indication from the proxy slave to the proxy master via the Ethernet network that the L1 synchronization between the proxy slave and the radio equipment controller was not achieved and repeating (a), (b), and (c) using a plurality of other link bit rates until a common matching link bit rate is achieved among the radio equipment controller, the proxy slave, the proxy master, and the radio equipment; and
(e) upon the common matching link bit rate being achieved, establishing a CPRI link between the radio equipment controller and the radio equipment using the common matching link bit rate.

9. The media of claim 8 , wherein communicating the indication from the proxy slave to the proxy master further comprises:
communicating the indication from the proxy slave to the proxy master using an out-of-band control channel between the proxy slave and the proxy master.

10. The media of claim 8 , wherein communicating the link bit rate from the proxy master to a proxy slave further comprises:
communicating the link bit rate from the proxy master to the proxy slave using an out-of-band control channel between the proxy master and the proxy slave.

11. The media of claim 8 , wherein performing the CPRI L1 link auto-negotiation with the radio equipment by the proxy master further comprises:
resetting a CPRI link between the proxy master and the radio equipment after the L1 synchronization between the proxy master and the radio equipment is achieved.

12. The media of claim 8 , wherein performing the CPRI L1 link auto-negotiation with the radio equipment controller by the proxy slave further comprises:
determining, by the proxy slave, whether a hyper frame number synchronization between the proxy slave and the radio equipment controller is achieved using the link bit rate for a CPRI bit stream received from the radio equipment controller at the link bit rate;
transmitting, by the proxy slave, a CPRI bit stream towards the radio equipment controller using only the link bit rate received from the proxy master upon determining the hyper frame number synchronization; and
stopping the transmitting by the proxy slave after 10 hyper frames.

13. The media of claim 8 , wherein based on determining that the L1 synchronization between the proxy slave and the radio equipment controller is achieved using the link bit rate, the operations further comprising:
communicating an indication from the proxy slave to the proxy master to allow CPRI link auto-negotiation operations to be performed between the radio equipment contr

Assignees

• Cisco Tech Inc

Inventors

• Anand Prashant
• Kumar Manoj
• Kayamkulangara Sudhir
• K Dinuraj
• Boopalan Manigandan

Classifications

• H04W76/10

  Connection setup · CPC title

• H04J3/0647

  Synchronisation among TDM nodes · CPC title

• H04W56/0005 Primary

  synchronizing of arrival of multiple uplinks · CPC title

• H04W56/001

  Synchronization between nodes · CPC title

• H04W84/20

  Leader-follower arrangements · CPC title