US 11,696,242 B2
Link auto-negotiation between a radio equipment controller (REC) and radio equipment (RE) in an ethernet-based fronthaul network
Prashant Anand, Bangalore (IN); Manoj Kumar, Karnataka (IN); Sudhir Kayamkulangara, Karnataka (IN); Dinuraj K, Karnataka (IN); and Manigandan Boopalan, Bangalore (IN)
Assigned to CISCO TECHNOLOGY, INC., San Jose, CA (US)
Filed by Cisco Technology, Inc., San Jose, CA (US)
Filed on Jul. 28, 2021, as Appl. No. 17/386,714.
Application 17/386,714 is a continuation of application No. 16/435,946, filed on Jun. 10, 2019, granted, now 11,228,991.
Claims priority of application No. 201941003988 (IN), filed on Feb. 1, 2019.
Prior Publication US 2021/0360555 A1, Nov. 18, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. H04W 56/00 (2009.01); H04W 28/22 (2009.01); H04W 76/10 (2018.01); H04W 84/20 (2009.01)
CPC H04W 56/0005 (2013.01) [H04W 28/22 (2013.01); H04W 56/001 (2013.01); H04W 76/10 (2018.02); H04W 84/20 (2013.01)] 18 Claims
OG exemplary drawing
 
7. A proxy master system for use in a fronthaul network environment comprising a radio equipment controller connected to a proxy slave, the proxy master system connected to a radio equipment, and a fronthaul Ethernet network connecting the proxy master system and the proxy slave, and for establishing a Common Public Radio Interface (CPRI) link between the radio equipment controller and the radio equipment over the fronthaul Ethernet network;
the proxy master system comprising at least one memory element for storing data; and
at least one processor for executing instructions associated with the data, wherein executing the instructions causes the proxy master system to perform operations, comprising:
receiving, from the proxy slave over the fronthaul Ethernet network, a message to trigger initiation of a Common Public Radio Interface (CPRI) Layer 1 (L1) link auto-negotiation with a radio equipment, wherein the received message identifies a first link bit rate to be used in the CPRI L1 link auto-negotiation;
initiating, by the proxy master system, the CPRI L1 link auto-negotiation with the radio equipment by transmitting a CPRI bit stream to the radio equipment at the first link bit rate; and
attempting to receive a CPRI bit stream from the radio equipment at the first link bit rate;
determining whether frame alignment is achieved at the first link bit rate based on the CPRI bit stream received from the radio equipment;
if frame alignment is not achieved, repeating the transmitting and attempting steps at one or more additional link bit rates until achieving frame alignment of a CPRI bit stream received from the radio equipment;
upon receiving a CPRI bit stream at the proxy master system from the radio equipment at a frame-aligned link bit rate, sending a message over the fronthaul Ethernet network to the proxy slave, wherein the sent message identifies the frame-aligned link bit rate;
wherein the sent message is further operative to cause the proxy slave to attempt local L1 sync between the proxy slave and the radio equipment controller by transmitting a CPRI stream to the radio equipment controller at the frame-aligned link bit rate; and
responsive to completion of the local L1 sync, establishing a CPRI link between the radio equipment controller and the radio equipment using the frame-aligned link bit rate.