Patent Application
20230309160
The present disclosure relates to Radio Access Network (RAN) for 4G- and 5G-based mobile networks, and relates more particularly to Open RAN (O-RAN) configuration for Narrowband Internet of Things (NBIOT) cells.
Currently, O-RAN standard based packet networking fronthaul (FH) interface between distributed unit (DU) and radio unit (RU) for 4G LTE and/or 5G New Radio (NR) radio access technologies (RAT) has attracted much attention in the wireless cellular communication industry. One of the primary reasons for such growth is that O-RAN specification allows interoperability and standardization of RAN components, e.g., O-RAN compliant DU (O-DU) and O-RAN compliant RU (O-RU), by including a unified interconnection standard over packet-based transport interfaces such as evolved Common Public Radio Interface (eCPRI) and Radio over Ethernet (ROE). This capability has enabled seamless integration of white-box hardware and open-source software elements from different component vendors for O-DUs and O-RUs.
O-RAN standard specification supports 4G and 5G NR radio access technologies (RAT) based layer 1 functional split 7.2× (FS-7.2×), in which frequency domain data in-phase/quadrature (IQ) samples and related control, management and synchronization information are carried over the fronthaul (FH) interface. This allows 4G and NR base-station systems (eNB and gNB) to be designed and deployed more cost effectively and efficiently. However, the current fronthaul O-RAN specifications for the control, user, and synchronization planes (CUS-plane) and management plane (M-plane) support only 4G LTE and 5G NR RATs. Specifically, the current O-RAN standard does not provide sufficient support to carry NBIOT carrier (of any mode, e.g., inband, guardband and/or standalone) data, control, and/or related management information over the FH interface. Currently, the O-RAN specification support relevant to NBIOT carriers is limited to subcarrier spacing (SCS) definition and Filter Index for NBIOT carriers. NBIOT is currently supported on traditional radios (non-O-RAN), such as common public radio interface (CPRI) radio as per 3GPP specification.
Therefore, there is a need for multiple enhancements in connection with O-RAN standards for seamless integration of NBIOT in O-RAN.
According to an example embodiment of the present disclosure, a set of additions to the current O-RAN standard is provided regarding C/U-plane and M-Plane requirements to enable NBIOT transport over the FH.
The additions presented in the present disclosure do not change with hybrid and hierarchical M-Plane models as they do not impact existing M-plane procedures. The additional parameters will be transported as part of existing user plane configuration, which is already defined in the standard for hybrid and hierarchical models.
According to an example embodiment of the present disclosure, in the case NBIOT inband and/or guardband-capable O-RAN radio unit (RU) (also referenced as RRU) receives i) LTE and/or NR IQ samples (signal) and ii) NBIOT IQ samples (signal) from separate endpoints (e.g., LTE/NR IQ samples from LTE/NR virtualized Distributed Unit (vDU) and NBIOT IQ samples from NBIOT VDU; or LTE/NR IQ samples (signal) and NBIOT IQ samples (signal) in different end points from a single common VDU), O-RAN RU is configured to be able to support combining LTE/NR signals and NBIOT inband/guardband signals in either frequency domain (e.g., by combining before FFT block) or in time domain (e.g., by combining after FFT block). Guardband mode refers to NB-IoT carrier being deployed in the guardband between two LTE carriers, and inband mode refers to NB-IoT carrier being deployed in resource blocks of an LTE carrier.
According to an example embodiment of the present disclosure, enhanced definition is added to two parameters, supportedtechnology-dl and supportedtechnology-ul, in YANG model under RU capability to support NBIOT. The YANG model defines a hierarchical data structure, which can be used for operations based on network configuration management protocols (e.g., Network Configuration Protocol (NETCONF) and Representational State Transfer Configuration Protocol (RESTCONF)), which operations can include configuration, status data, remote procedure calls (RPCs), and notifications.
According to an example embodiment of the present disclosure, the O-RAN radio unit (O-RU) (also referred to as remote radio unit (RRU)) is configured to expose its capability to support NBIOT (e.g., in at least one of standalone, inband and/or guardband mode) for each endpoint by exposing the supported-technology-dl and/or supported-technology-ul parameter(s) under tx-arrays and/or rx-arrays.
According to an example embodiment of the present disclosure, LTE/NR and NBIOT (e.g., in inband and/or guardband mode) shall configure separate endpoints at the radio. In this example embodiment, separate eAxC IDs will be used for LTE/NR and NBIOT (e.g., in inband and/or guardband mode).
According to an example embodiment of the present disclosure, a new parameter is added under low-level-tx-endpoints and/or low-level-rx-endpoints of User-plane YANG model defined in ORAN fronthaul M-plane specification, thereby enabling the O-RAN RU to know the mapping of NBIOT endpoint to corresponding LTE/NR endpoint.
According to an example embodiment of the present disclosure, instead of adding a new parameter to indicate the mapping between the end points of LTE/NR and NBIOT (e.g., in inband and/or guardband mode), a bit field in the existing Extended Antenna Carrier Identifier (eAxC-ID) parameter is used to determine the relation between LTE/NR and NBIOT (e.g., in inband and/or guardband mode) end points.
According to an example embodiment of the present disclosure, O-DU shall instruct O-RU to detect NBIOT Physical random access channel (NPRACH) by sending an existing O-RAN section type-3 C-Plane message.
According to an example embodiment of the present disclosure, required parameters to detect NPRACH shall be sent from O-DU to O-RU via M-plane during User-Plane configuration.
According to an example embodiment of the present disclosure, support of NBIOT in module capability of O-RAN RU (or O-RU) is provided by adding (addition underlined below) enhanced definition to following two parameters (supportedtechnology-dl and supportedtechnology-ul) in YANG model under RU capability:
enum NBIOT {
}
enum NBIOT-inband-LTE {
}
enum NBIOT-guardband-LTE {
}
enum NBIOT-inband-NR {
}
enum NBIOT-guardband-NR {
}
enum NBIOT {
}
enum NBIOT-inband-LTE {
}
enum NBIOT-guardband-LTE {
}
enum NBIOT-inband-NR {
}
enum NBIOT-guardband-NR {
}
According to an example embodiment of the present disclosure, capability of the O-RAN RU to support NBIOT (e.g., at least one of inband, guardband and/or standalone mode) for each endpoint can be shown by the O-RAN RU by exposing the supported-technology-dl and supported-technology-ul parameters under tx-arrays (transmit) and/or rx-arrays (receive). Example possible values for the supported-technology-dl and supported-technology-ul parameters can be, e.g., as described above in connection with the enhanced definition, or as provided below (addition underlined below):
According to an example embodiment of the present disclosure, LTE (and/or 5G NR) and NBIOT (e.g., in inband and/or guardband mode) configure separate endpoints at the O-RAN RU. In this example embodiment, separate Extended Antenna Carrier Identifiers (Eaxc-ID eAxC IDs) will be used for LTE (and/or 5G NR) and NBIOT (e.g., in inband and/or guardband mode). This example embodiment is applicable to both i) the case in which LTE (and/or 5G NR) and NBIOT are hosted on the single common VDU, and ii) the case in which LTE (and/or 5G NR) and NBIOT are hosted on separate VDUs.
According to an example embodiment of the present disclosure, a new parameter is added under low-level-tx-endpoints and/or low-level-rx-endpoints of User-plane YANG model defined in ORAN fronthaul M-plane specification, thereby enabling the O-RAN RU to know the mapping of NBIOT endpoint to corresponding LTE/NR endpoint, which in turn enables O-RAN RU to combine LTE/NR signal and NBIOT inband/guardband signal in DL (and to separate these signals in UL). One example addition of optional parameter (underlined below) to low-level-tx-endpoints to point to NBIOT's low-level-tx-endpoints is shown below:
One example addition of optional parameter (underlined below) to low-level-rx-endpoints to point to NBIOT's low-level-rx-endpoints is shown below:
According to an example embodiment of the present disclosure, as an alternative to adding a new parameter to indicate the mapping between the end points of LTE/NR and NBIOT (e.g., in inband and/or guardband mode), a bit field in the existing Extended Antenna Carrier Identifier (eAxC-ID) parameter is used to determine the relation between LTE/NR and NBIOT (e.g., in inband and/or guardband mode) end points.
According to an example embodiment of the present disclosure, O-DU instructs O-RU to detect NBIOT Physical random access channel (NPRACH) by sending an existing O-RAN section type-3 C-Plane message. In one example implementation, this O-RAN section type-3 C-Plane message can be sent once per symbol group. Alternatively, O-RAN section type-3 C-Plane message can be sent once per repetition. In the implementation involving sending of the O-RAN section type-3 C-Plane message once per symbol group, the O-RAN section type-3 C-Plane message is sent at the subframe where NPRACH symbol group starts. As the symbol group is not aligned to sub-frame, offset from the current sub-frame shall be mentioned. In the implementation involving sending of the O-RAN section type-3 C-Plane message once per repetition, the O-RAN section type-3 C-Plane message is sent at the subframe where NPRACH repetition starts. As the repetition is not aligned to sub-frame, offset from the current sub-frame shall be mentioned.
According to an example embodiment of the present disclosure, required parameters to detect NPRACH are sent from O-DU to O-RU via M-plane during User-Plane configuration. O-RU will be able to detect NPRACH without receiving any control plane message from O-DU based on the parameters shown below configured via M plane:
| Number | Date | Country | Kind |
|---|---|---|---|
| 202221016724 | Mar 2022 | IN | national |
