Patent Application
20150146613
The field of this invention relates to a method and apparatus for resetting at least one node within a Common Public Radio Interface (CPRI) radio base station system.
The Common Public Radio Interface (CPRI™) is an industry cooperation defining a publicly available specification for the key internal interface of radio base stations within, for example, a cellular communication network. In particular, the CPRI specification is currently defined based on standards such as the Universal Mobile Telecommunications System (UMTS), WiMAX Forum Mobile System Profile based on IEEE 802. 16-2009, Evolved UMTS Terrestrial Radio Access (E-UTRA), and GSM (Global System for Mobile communications).
CPRI focuses on a simplified radio base station architecture, dividing the radio base station into a radio subsystem and a control subsystem, and specifying a single interface between the two subsystems. Typically, the control subsystem, made up of one or more Radio Equipment Control (REC) nodes, is concerned with the network interface transport, the radio base station control and management as well as the digital baseband processing. The radio subsystem, made up of one or more Radio Equipment (RE) nodes, typically provides the analogue and radio frequency functions such as filtering, modulation, frequency conversion and amplification. The two subsystems of a base station system may be physically separated; for example the RE node may be located close to the antenna of the base station, whilst the REC node may be located in a more conveniently accessible site. Alternatively, the REC and RE nodes may be co-located as in a conventional radio base station design. The specifications defining the CPRI interface are available at http://www.cpri.info/spec.html, and are incorporated by reference herein in their entirety.
However, a problem of the known system is that when the REC node that initiates the reset is not located at an uplink end of the CPRI chain; i.e. when the REC node initiating the reset is a networking REC node, resetting all nodes within a CPRI chain is complex. More specific, at least one further reset command is required to initiate the transmission of such a downlink reset request notification. The need for such additional intervention from, say, an application layer core in order to generate the additional reset commands is undesirable, and there is a customer driven need for the resetting of all nodes within a CPRI chain using a single reset command, irrespective of the CPRI architecture topology and location of the reset initiating REC node therein.
The present invention provides a method of resetting at least one node within a Common Public Radio Interface (CPRI) radio base station system, a CPRI Radio Equipment Controller (REC) module, a CPRI REC node comprising such a CPRI REC module, a radio base station system comprising such a CPRI REC node, and a wireless communication system comprising such a radio base station system as described in the accompanying claims.
Specific embodiments of the invention are set forth in the dependent claims.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
Further details, aspects and embodiments of the invention will be described, by way of example only, with reference to the drawings. In the drawings, like reference numbers are used to identify like or functionally similar elements. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale.
The present invention will now be described with reference to the accompanying drawings in which an example of a Common Public Radio Interface (CPRI™) architecture is illustrated and described. In particular, an example of CPRI architecture comprising a simple chain topology is illustrated and described. However, it will be appreciated that the present invention is not limited to such a topology, and may equally be implemented within CPRI architectures comprising alternative topologies such as, by way of example only, start topologies, ring topologies, tree topologies, etc. Furthermore, because the illustrated embodiments of the present invention may for the most part, be implemented using electronic components and circuits known to those skilled in the art, details will not be explained in any greater extent than that considered necessary as illustrated below, for the understanding and appreciation of the underlying concepts of the present invention and in order not to obfuscate or distract from the teachings of the present invention.
In some examples of the invention, there is provided a method of resetting at least one node within a CPRI radio base station system, the method comprising, at an end-point REC node within the CPRI radio base station system, receiving on a slave port a reset notification, and in response thereto transmitting on the slave port a reset notification comprising a reset bit being set within at least ten hyperframes.
Furthermore, in some examples of the invention, there is provided a CPRI REC module arranged to provide CPRI functionality within an end-point REC node. The CPRI module is arranged to receive on a slave port thereof a reset notification, and in response thereto transmit on the slave port a reset notification comprising a reset bit being set within at least ten hyperframes.
Furthermore, in some examples of the invention, there is provided a CPRI REC module arranged to provide CPRI functionality within a networking REC node. The CPRI module is arranged to receive on a master port thereof a reset notification comprising a reset bit being set within at least ten hyperframes, and in response thereto transmit on a slave port thereof a reset notification comprising a reset bit being set within at least ten hyperframes.
Furthermore, in some examples of the invention, there is provided a CPRI REC module arranged to provide CPRI functionality within a reset initiating REC node. The CPRI module is arranged to receive a reset command, and in response thereto transmit on an uplink of at least one master port thereof a reset notification.
In addition to the basic system configuration illustrated in
The remote resetting of nodes is managed by way of a Reset bit within each hyperframe (one hyperframe being made up of 256 basic frames), whereby the Reset bit, bit Z. 130.0 of the L1-inband protocol, is used for reset request notifications on downlinks (i.e. in the direction from an REC node 110 to an RE node 120), and for reset acknowledgement notifications on uplinks (i.e. in the direction from an RE node 120 to an REC node 110). A reset request notification comprises the Reset bit being ‘set’ (i.e. being set to a ‘1’ value) for at least 10 hyperframes, whilst a reset acknowledgement notification comprises the Reset bit being set for at least 5 hyperframes. The CPRI specification also states that a reset request notification can only be sent from a master port to a slave port. When a node receives a valid reset notification on any of its slave ports, it not only resets itself, but also forwards the reset request notification on all (if any) of its master ports.
The second REC node 320 receives the reset request notification 360 transmitted by the end-point REC node 310 on a slave port 324 thereof, and in response thereto a reset request interrupt may be generated in order to inform, say, an application layer (not shown) of the REC node 320 that a reset of the node is required. Alternatively, the application layer (not shown) may be arranged to poll the values of the L1-inband protocol to determine when a reset of the node is required. The second REC node 320 then forwards the reset request on to the next node in the chain by transmitting on a master port 322 thereof a reset request notification 362 over the CPRI link 350 to the third REC node 330.
The third REC node 330 receives the reset request notification 362 transmitted by the second REC node 320 on a slave port 334 thereof, and in response thereto a reset request interrupt may be generated in order to inform, say, an application layer (not shown) of the REC node 330 that a reset of the node is required. The third REC node 330 then forwards the reset request on to the next node in the chain by transmitting on a master port 332 thereof a reset request notification 364 over the CPRI link 350 to the RE node 340.
The RE node 340 receives the reset request notification 364 transmitted by the third REC node 330 on a slave port 344 thereof, and in response thereto a reset request interrupt may be generated in order to inform, say, an application layer (not shown) of the RE node 340 that a reset of the node is required. In the illustrated example, the RE node 340 is located at the end of the CPRI chain. Accordingly, the RE node 340 transmits on the slave port 344 a reset acknowledgement notification 370 over the CPRI link 350 back to the third REC node 330.
The third REC node 330 receives the reset acknowledgement notification 370 transmitted by the RE node 340 on its master port 332, and in response thereto a reset acknowledgement interrupt may be generated in order to inform, say, the application layer (not shown) of the REC node that the reset request notification transmitted to the downlink nodes (i.e. the RE node 340) has been acknowledged. The third REC node 330 then forwards the reset acknowledgement on up the chain by transmitting on its slave port 334 a reset acknowledgement notification 372 over the CPRI link 350 to the second REC node 320.
The second REC node 320 receives the reset acknowledgement notification 372 transmitted by the third REC node 330 on its master port 322, and in response thereto a reset acknowledgement interrupt may be generated in order to inform, say, the application layer (not shown) of the REC node that the reset request notification transmitted to the downlink nodes (i.e. the RE node 340 and the third REC node 330) has been acknowledged. The second REC node 320 then forwards the reset acknowledgement on up the chain by transmitting on its slave port 334 a reset acknowledgement notification 374 over the CPRI link 350 to the end-point REC node 310.
The end-point REC node 310 receives the reset acknowledgement notification 374 transmitted by the second REC node 320 on its master port 312, and in response thereto a reset acknowledgement interrupt may be generated in order to inform, say, the application layer (not shown) of the end-point REC node that all downlink nodes have acknowledged the reset notification. Thus, in this manner, a single reset command may be used to initiate a reset of all the nodes within the CPRI chain. In particular, when the end-point REC node is located at an uplink end of the CPRI chain, all nodes in the CPRI chain are able to be reset using a single reset command whilst confirming to the CPRI specification requirements of:
In order to reset the reset subordinate REC nodes 410, 420 located in the uplink direction within the CPRI chain, the third REC node 430 transmits on a master port 432 thereof a reset request notification 360 over the CPRI link 450 to the second REC node 320.
The second REC node 420 receives the reset request notification 460 transmitted by the third REC node 430 on a slave port 424 thereof, and in response thereto a reset request interrupt may be generated. The second REC node 420 then forwards the reset request on to the next node in the chain by transmitting on a master port 422 thereof a reset request notification 462 over the CPRI link 450 to the first REC node 410.
The first REC node 410 receives the reset request notification 462 transmitted by the second REC node 420 on a slave port 414 thereof, and in response thereto a reset request interrupt may be generated. In the example illustrated in
The second REC node 420 receives the reset acknowledgement notification 464 transmitted by the first REC node 410 on its master port 422, and in response thereto a reset acknowledgement interrupt may be generated. The second REC node 420 then forwards the reset acknowledgement on to the third REC node 430 by transmitting on its slave port 334 a reset acknowledgement notification 466 over the CPRI link 450 to the third REC node 430.
The third REC node 430 receives the reset acknowledgement notification 466 transmitted by the second REC node 420 on its master port 432, and in response thereto a reset acknowledgement interrupt may be generated. In this manner, the reset subordinate REC nodes located upstream of the third REC node 430 may be reset by a single command.
Referring now to
The CPRI radio base station system 500 illustrated in
Referring now to
The reset notification transmitted by the master REC node is then received on an uplink of a slave port of a networking REC node at 815, and a reset request interrupt is generated at 820. For example, in the example illustrated in
If, at 825, the REC node that received the reset notification on an uplink of a slave port thereof comprises one or more master ports, i.e. the REC node comprises a networking REC node and not an end-point REC node, the method moves on to 830, where a reset notification comprising the Reset bit being set for at least ten hyperframes is transmitted on the (or each) master port of the REC node, and the method loops back to 815 where the reset notification is received on an uplink of a slave port of a next REC node in the chain. For example, in
Referring back to 825, if the REC node that received the reset notification on an uplink of a slave port thereof comprises no master ports, i.e. the REC node comprises an end-point REC node such as the first REC node 510 in
The reset notification transmitted by the REC node on a downlink of the slave port thereof is subsequently received on a master port of an REC node at 840, and a reset acknowledgement interrupt is generated at 845. For example, in the example illustrated in
If, at 850, the REC node that received the reset notification on a downlink of a master port thereof comprises one or more slave ports, i.e. the REC node is reset initiating REC node, the method loops back to 835, where a reset acknowledgement notification comprising the Reset bit being set for at least ten hyperframes is transmitted on a downlink of the (or each) slave port. For example, in
Referring back to 850, if the REC node that received the reset notification on a downlink of a master port thereof comprises no slave ports, i.e. the REC node is the reset initiating REC node, the method moves on to 905 (
Note that, since the reset acknowledgement notification 572 received on the upstream master port 532 comprised the Reset bit being set for at least ten hyperframes, as opposed to just five in conventional implementations, the reset request notification 580 based thereon will also comprise the Reset bit being set for at least ten hyperframes, and thus will fulfil the requirements for a reset request notification defined in the CPRI specification. Had the reset acknowledgement notification 572 received by the third REC node 530 comprised a conventional reset acknowledgement notification comprising the Reset bit being set for only at least five hyperframes, subsequent reset request notification 580 transmitted by the third REC node 530 to the RE node 540 would also only comprise the Reset bit being set for at least five hyperframes, requiring all nodes located on the downstream side of the third REC node 530 to interpret the Reset bit being set for at least five hyperframes on their slave ports as representing a reset request notification, which would be in violation of the CPRI specification, and thus would not be an acceptable solution.
The reset notification transmitted by the reset initiating REC node is then received on a downlink of a slave port of a node at 910, and a reset request interrupt is generated at 915. For example, in the example illustrated in
If, at 920, the node that received the reset notification on a downlink of a slave port thereof is not an RE node, the method loops back to 905. In this manner, a downlink reset request notification sequence may be implemented, whereby a reset request comprising the Reset bit being set for at least ten hyperframes may be sequentially transmitted along REC nodes within the CPRI node chain in the downlink direction.
Referring back to 920, if the node that received the reset notification on a downlink of a slave port thereof is an RE node, the method moves on to 925, where a reset acknowledgement notification is transmitted back on a uplink of the slave port on which the reset notification received thereby had been received. For example, in
The reset notification transmitted on the uplink of the slave port is subsequently received on a master port of an upstream REC node at 930, and a reset acknowledgement interrupt is generated at 935. For example, in the example illustrated in
If, at 960, the REC node that received the reset notification on the uplink of a master port thereof comprises one or more slave ports, i.e. is not the reset initiating REC node, the method loops back to 925. Conversely, if the REC node that received the reset notification on the uplink of a master port thereof comprises no slave ports, i.e. is the reset initiating REC node, the method ends.
In the illustrated example, the present invention has been described in relation to an example CPRI radio base station system 500 comprising only a single RE node 540. However, it will be appreciated that the present invention may equally be implemented within a CPRI radio base station system comprising a plurality of RE nodes 540. Accordingly, it will be understood that the method of
Furthermore, in the illustrated example, the REC nodes are arranged to generate reset request interrupts and reset acknowledgement interrupts upon receipt of respective reset notifications. However, in some examples, the application layer of the respective nodes may be arranged to poll the values of the L1-inband protocol to determine when a reset request/acknowledgement notification has been received, alleviating the need for such interrupts.
In the foregoing specification, the invention has been described with reference to specific examples of embodiments of the invention. It will, however, be evident that various modifications and changes may be made therein without departing from the broader spirit and scope of the invention as set forth in the appended claims.
The connections as discussed herein may be any type of connection suitable to transfer signals from or to the respective nodes, units or devices, for example via intermediate devices. Accordingly, unless implied or stated otherwise, the connections may for example be direct connections or indirect connections. The connections may be illustrated or described in reference to being a single connection, a plurality of connections, unidirectional connections, or bidirectional connections. However, different embodiments may vary the implementation of the connections. For example, separate unidirectional connections may be used rather than bidirectional connections and vice versa. Also, plurality of connections may be replaced with a single connection that transfers multiple signals serially or in a time multiplexed manner. Likewise, single connections carrying multiple signals may be separated out into various different connections carrying subsets of these signals. Therefore, many options exist for transferring signals.
Those skilled in the art will recognize that the boundaries between logic blocks are merely illustrative and that alternative embodiments may merge logic blocks or circuit elements or impose an alternate decomposition of functionality upon various logic blocks or circuit elements. Thus, it is to be understood that the architectures depicted herein are merely exemplary, and that in fact many other architectures can be implemented which achieve the same functionality. For example, in
Any arrangement of components to achieve the same functionality is effectively ‘associated’ such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as ‘associated with’ each other such that the desired functionality is achieved, irrespective of architectures or intermediary components. Likewise, any two components so associated can also be viewed as being ‘operably connected,’ or ‘operably coupled,’ to each other to achieve the desired functionality.
Furthermore, those skilled in the art will recognize that boundaries between the above described operations merely illustrative. The multiple operations may be combined into a single operation, a single operation may be distributed in additional operations and operations may be executed at least partially overlapping in time. Moreover, alternative embodiments may include multiple instances of a particular operation, and the order of operations may be altered in various other embodiments.
Also for example, the examples, or portions thereof, may implemented as soft or code representations of physical circuitry or of logical representations convertible into physical circuitry, such as in a hardware description language of any appropriate type.
Also, the invention is not limited to physical devices or units implemented in non-programmable hardware but can also be applied in programmable devices or units able to perform the desired device functions by operating in accordance with suitable program code, such as mainframes, minicomputers, servers, workstations, personal computers, notepads, personal digital assistants, electronic games, automotive and other embedded systems, cell phones and various other wireless devices, commonly denoted in this application as ‘computer systems’.
However, other modifications, variations and alternatives are also possible. The specifications and drawings are, accordingly, to be regarded in an illustrative rather than in a restrictive sense.
In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word ‘comprising’ does not exclude the presence of other elements or steps then those listed in a claim. Furthermore, the terms ‘a’ or ‘an,’ as used herein, are defined as one or more than one. Also, the use of introductory phrases such as ‘at least one’ and ‘one or more’ in the claims should not be construed to imply that the introduction of another claim element by the indefinite articles ‘a’ or ‘an’ limits any particular claim containing such introduced claim element to inventions containing only one such element, even when the same claim includes the introductory phrases ‘one or more’ or ‘at least one’ and indefinite articles such as ‘a’ or ‘an.’ The same holds true for the use of definite articles. Unless stated otherwise, terms such as ‘first’ and ‘second’ are used to arbitrarily distinguish between the elements such terms describe. Thus, these terms are not necessarily intended to indicate temporal or other prioritization of such elements. The mere fact that certain measures are recited in mutually different claims does not indicate that a combination of these measures cannot be used to advantage.
