ORAN-based RRU low power consumption control method and system

Abstract

The invention provides an ORAN-based RRU low power consumption control method and system, relates to the technical field of wireless communication, and solves the problems that under an ORAN architecture, when an RRU is in deep sleep, standby power consumption is too high, and a wake-up mechanism lacks flexibility. The method comprises the following steps: a DU sends an M-plane message to an RRU through a forward transmission interface, and instructs the RRU to enter a target low-power-consumption mode; the RRU responds to the M-plane message and executes a power management operation to enter a target low-power-consumption mode; in the target low-power-consumption mode, interaction is carried out between an MCU and a DU of the RRU based on a physical layer control signal of an optical port and by following a predetermined communication protocol, and a state monitoring and control link of the RRU is maintained; and when the target low-power-consumption mode needs to be quitted, the DU sends a quit instruction to the RRU through the physical layer control signal and a predetermined communication protocol. According to the invention, the advantages and effects that the RRU is energy-saving and the standby time is prolonged can be achieved.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and specifically to a low-power control method and system for RRUs based on ORAN. Background Technology

[0002] With the continuous development of wireless communication networks, the density and scale of base station deployments are constantly increasing. As a key node for wireless signal transmission and reception, the Remote Radio Unit (RRU) typically needs to maintain high-power operation for extended periods in practical applications to ensure network coverage continuity and communication service quality. This continuous energy consumption not only constitutes a significant operating cost burden for operators, but in areas with weak or unstable power infrastructure, it can also directly restrict the normal operating time of base station equipment, affecting network availability. Furthermore, prolonged high-power operation leads to significant internal temperature rise, accelerating the aging process of electronic components and potentially increasing the risk of hardware failure, adversely affecting the overall reliability and maintenance costs of the network.

[0003] As wireless access networks evolve towards openness and intelligence, the ORAN architecture, through decoupling and standardized interfaces, brings greater flexibility and openness to the network. However, how to achieve efficient and deep power management of RRUs under this architecture remains a topic worthy of in-depth exploration. While the existing ORAN protocol framework defines various energy-saving levels, including SM1, SM2, SM3, and SM4, with SM4 being a deep sleep mode designed to reduce power consumption under low service loads, this mode, while achieving power savings, still requires maintaining the power supply and activity of the eCPRI fronthaul interface and related management planes to ensure wake-up via M-Plane messages. This results in relatively considerable standby power consumption for devices in SM4 mode, leaving room for improvement in power reduction for extremely demanding power supply environments or scenarios requiring extreme energy efficiency.

[0004] On the other hand, in pursuit of lower standby power consumption, some solutions adopt more aggressive power-saving strategies, such as directly shutting down the power supply to the fronthaul optical port. While these methods can significantly reduce power consumption, they often come at the cost of sacrificing the flexibility and timeliness of wake-up. Their wake-up mechanisms typically rely on preset timers or simple hardware triggers, failing to intelligently respond to potential service growth or management commands from the network side, and making it difficult to quickly restore service capabilities through the standard ORAN interface when needed. This rigid control mode may result in network resources not being able to be scheduled in real time as needed, affecting user experience and being incompatible with the future trend of intelligent and flexible network development.

[0005] Therefore, in current ORAN scenarios, low-power control technologies for RRUs, especially when seeking deep energy-saving solutions that surpass SM4 mode, face the dual challenge of balancing extremely low standby power consumption with flexible, reliable, and fast wake-up capabilities. The industry urgently needs to explore an innovative control mechanism that can achieve standby power consumption far below the current SM4 level while ensuring the existence and manageability of the fronthaul physical link. Simultaneously, it must ensure that the RRU can be reliably and promptly woken up and resume normal operation in an efficient and low-cost manner according to the actual needs of the network, thereby truly expanding the applicable scenarios and endurance of the equipment. Summary of the Invention

[0006] The purpose of this invention is to solve the problems of excessive standby power consumption and lack of flexibility in the wake-up mechanism of RRUs in deep sleep under the ORAN architecture. Therefore, a low-power control method and system for RRUs based on ORAN is proposed. In the ORAN scenario, this invention enables the DU to control the RU through the optical port, realizing the entry and exit of the super low-power mode, thereby achieving the advantages of RRU energy saving and increased standby time.

[0007] The present invention employs the following technical solutions to achieve its objective: A low-power control method for RRUs based on ORAN, comprising the following steps: S1. The distributed unit (DU) sends a management plane M-Plane message to the remote radio unit (RRU) through the fronthaul interface, instructing the RRU to enter the target low-power mode. S2. In response to the M-Plane message, the RRU performs a power management operation to enter the target low-power mode; wherein, the power management operation includes cutting off the power supply to unnecessary circuits and maintaining the microcontroller unit (MCU) and at least one optical port in an active state. S3. In the target low-power mode, the MCU of the RRU and the DU interact based on the physical layer control signal of the optical port and follow a predetermined communication protocol to maintain the status monitoring and control link of the RRU. S4. When the RRU needs to exit the target low-power mode, the DU sends an exit command to the RRU through the physical layer control signal and the predetermined communication protocol. S5. After monitoring and parsing the exit instruction, the MCU of the RRU controls the restoration of power supply to the non-essential circuits so that the RRU exits the target low-power mode and resumes normal operation.

[0008] Specifically, in step S1, instructing the RRU to enter the target low-power mode includes: the DU sending the M-Plane message to the RRU through the eCPRI fronthaul interface, the M-Plane message being encapsulated using the NETCONF protocol; the M-Plane message containing control information indicating the target low-power level that the RRU enters, the target low-power level including at least one ultra-low power level.

[0009] Preferably, the target low-power level is defined by a set of low-power levels supported in a predefined configuration data model of the RRU; wherein the set of low-power levels includes at least the super low-power level, which is configured to disconnect power to circuits other than the microcontroller unit (MCU) and the at least one optical port upon entry.

[0010] Preferably, when the target low power level is the super low power level, the total power consumption of the RRU after entering the target low power mode is controlled to be no more than 5 watts.

[0011] Specifically, in step S2, the power management operation includes cutting off the power supply to non-essential circuits, specifically cutting off the power supply to the power amplifier circuit, radio frequency circuit, clock circuit, and main digital circuit inside the RRU; wherein, the main digital circuit does not include the microcontroller unit (MCU) and the interface circuit directly related to the operation of the at least one optical port.

[0012] Preferably, in step S3, interaction is performed based on the physical layer control signal of the optical port and in accordance with a predetermined communication protocol. Specifically, this includes: the MCU of the RRU and the DU control the transmission disable TX_DISABLE signal and monitor the loss of received signal RX_LOS signal of their respective optical modules, and encapsulate and parse the interaction information using the Universal Asynchronous Receiver / Transmitter (UART) protocol, thereby achieving bidirectional communication.

[0013] Furthermore, in the target low-power mode, the process of maintaining the status monitoring and control link between the MCU of the RRU and the DU specifically includes: the MCU of the RRU encapsulates the status information into a first control sequence according to the UART protocol, and sends the first control sequence to the DU by controlling the change of the TX_DISABLE signal of the local optical module; the DU obtains the first control sequence by monitoring the change of the RX_LOS signal of its optical module, and parses the current status information of the RRU according to the UART protocol.

[0014] Furthermore, in step S4, the DU sends an exit command to the RRU through the physical layer control signal and the predetermined communication protocol. Specifically, the DU encapsulates the exit control command into a second control sequence according to the UART protocol, and sends the second control sequence to the RRU by controlling the change of the TX_DISABLE signal of its own optical module. The MCU of the RRU obtains the second control sequence by monitoring the change of the RX_LOS signal of its own optical module, and parses the exit control command according to the UART protocol as the exit command.

[0015] Specifically, in step S5, after the RRU's MCU monitors and parses the exit instruction, it controls the restoration of power supply to the non-essential circuits. Specifically, the RRU's MCU first restores power supply to the clock circuit and circuits related to the main digital functions; after completing the above power restoration and confirming that the relevant circuits have been initialized, it then restores power supply to the RF circuit and power amplifier circuit in sequence; wherein, the process and sequence of power restoration are controlled by the preset power management logic within the RRU.

[0016] This invention also provides a low-power RRU control system for implementing the aforementioned method, the system comprising the following functional units: The message transmission and control unit, deployed on the distributed unit (DU) side, is used to send management plane M-Plane messages carrying target low power level information to the remote radio frequency unit (RRU) via the eCPRI fronthaul interface. It is also used to generate and send instructions to exit low power mode when needed. The power management and execution unit, deployed on the RRU side, is communicatively connected to the message transmission and control unit. It is used to respond to and parse the M-Plane message and perform corresponding power management operations according to the parsed low power level. The power management operations include cutting off the power supply to the power amplifier circuit, radio frequency circuit, clock circuit and main digital circuit, while maintaining the microcontroller unit (MCU) and at least one optical port in the working state. A low-power state interaction unit, deployed on the RRU side and the DU side, is used to establish and maintain an out-of-band communication link based on the optical port physical layer control signal after the RRU enters low-power mode. The low-power state interaction unit includes: an encoding module for encapsulating state information or control commands according to the Universal Asynchronous Receiver Transmitter (UART) protocol, and a physical signal modulation and demodulation module for transmitting the encapsulated information by controlling the optical module to transmit a TX_DISABLE signal or monitoring the received signal loss RX_LOS signal. An exit control and recovery unit, deployed on the RRU side, is connected to the low-power state interaction unit and the power management and execution unit. It is used to monitor and parse exit commands from the DU through the out-of-band communication link, and after parsing the exit command, trigger the power management and execution unit to restore the power supply of the circuits that have been cut off according to a predetermined sequence and process, so that the RRU exits the low-power mode and resumes normal operation.

[0017] In summary, due to the adoption of this technical solution, the beneficial effects of this invention are as follows: This invention enables extremely low standby power consumption of the RRU, with overall power consumption significantly lower than the typical level in the SM4 deep sleep mode of the current ORAN protocol. This deep energy-saving effect not only directly reduces the long-term operating energy consumption and cost of the base station, but also effectively extends the sustainable working time of the equipment in scenarios with tight power supply or reliance on backup power, thereby improving the availability of the network in special environments.

[0018] While achieving ultra-low power consumption, this invention maintains a stable, reliable, and low-cost out-of-band communication link. This link enables the distributed unit to continuously perceive the real-time status of the RRU and retains the full capability to remotely wake it up and control it. This design overcomes the disconnection and wake-up stagnation problems caused by simply cutting off the power to the fronthaul interface, ensuring the continuity and flexibility of network management.

[0019] Thanks to the full utilization of the existing ORAN architecture and the physical layer characteristics of the eCPRI fronthaul interface, this invention requires no major modifications to the network hardware or the addition of complex circuits. The core control logic of this invention is primarily implemented in software, using existing optical module control signals and a universal asynchronous serial protocol to encode and transmit information. Therefore, this invention has significant advantages such as low implementation cost, good compatibility, and ease of deployment and promotion in existing networks.

[0020] Based on the aforementioned remote monitoring and wake-up capabilities, network operators or intelligent management systems can dynamically and precisely adjust the operating mode of remote radio frequency units according to actual changes in service load. This not only enables refined energy-saving management of network resources on demand, avoiding impacts on user experience due to untimely wake-up, but also further improves the operational energy efficiency and intelligence level of the entire wireless access network.

[0021] In addition, the RRU generates significantly less internal heat in ultra-low power mode, which helps to slow down the aging process of equipment components and reduce the failure rate caused by long-term high-temperature operation, thereby indirectly extending the service life of the equipment and enhancing the long-term reliability and stability of network infrastructure. Attached Figure Description

[0022] The present invention is described in detail with reference to the following figures, which include six figures as follows: Figure 1 This is a schematic diagram illustrating the overall process of the RRU low-power control method of the present invention; Figure 2 This is a schematic diagram of the ORAN-based RRU ultra-low power control architecture in this invention; Figure 3 This is a schematic diagram illustrating the process by which the DU and RRU control the RRU to enter low-power mode via M-plane messages in this invention. Figure 4 This is a schematic diagram of the working architecture related to RRU power management in this invention; Figure 5 This is a schematic diagram of the communication process architecture between RRU and DU based on the UART protocol in the super low power mode of this invention. Figure 6 This is a schematic diagram of the RRU exiting ultra-low power consumption in this invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The parts of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0024] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0025] A low-power control method for RRUs based on ORAN. Figure 1 This document provides a brief overview of the overall process of the method, which can be viewed concurrently. The key steps of the method can be summarized as follows: S1. The Distributed Unit (DU) sends a Management Plane (M-Plane) message to the Remote Radio Unit (RRU) via the fronthaul interface, instructing the RRU to enter the target low-power mode. S2 and RRU respond to the M-Plane message and perform power management operations to enter the target low-power mode; wherein, the power management operations include cutting off the power supply to non-essential circuits and maintaining the microcontroller unit (MCU) and at least one optical port in an active state; S3. In the target low-power mode, the MCU and DU of the RRU interact based on the physical layer control signal of the optical port and follow the predetermined communication protocol to maintain the status monitoring and control link of the RRU. S4. When the RRU needs to exit the target low-power mode, the DU sends an exit command to the RRU through physical layer control signals and a predetermined communication protocol. After the S5 and RRU MCUs detect and parse the exit instruction, they control the restoration of power to non-essential circuits so that the RRU exits the target low-power mode and resumes normal operation.

[0026] This implementation method will be based on the above-described step sequence, and will describe the details of each step in detail.

[0027] like Figure 2 The diagram illustrates the complete control framework of this embodiment, primarily involving two entities: the Distributed Unit (DU) and the Remote Radio Unit (RRU). Through their coordinated operation, deep energy-saving control of the RRU's operating mode is achieved. This embodiment fully utilizes the interfaces and protocols defined by the ORAN standard, establishing a low-power out-of-band communication link at the physical layer. This ensures both extremely low standby power consumption and the continuity of network management while maintaining flexible wake-up capabilities.

[0028] In an ORAN network, the DU (Control Unit) acts as a centralized control and data processing unit, responsible for determining the operating state of the RRU (Remote Receiver Unit) based on network policies. As a front-end device for radio frequency signal transmission and reception, the RRU's power consumption accounts for a significant proportion of the base station's total power consumption. The core of this implementation is to enable the DU to instruct the RRU to enter a super-low-power state far below the power consumption level of the standard deep sleep mode, and to reliably and promptly wake the RRU from this state when service requirements necessitate it.

[0029] This implementation predefines the supported low-power capabilities on the RRU side, and the process for controlling the RRU to enter low-power mode can be referred to simultaneously. Figure 3 This is illustrated; it is accomplished by defining corresponding low-power levels in the RRU's configuration data model. For example, multiple levels such as SM4-L0, SM4-L1, and SM4-L2 can be defined in the model. Among them, SM4-L2 is defined as the ultra-low power level, whose characteristic is that when entering this mode, all circuits except the microcontroller unit (MCU) and the minimum circuitry necessary to maintain a physical optical port connection will be shut down. After the RRU starts up and establishes a normal eCPRI fronthaul connection with the DU, it will proactively report the set of low-power levels it supports to the DU through the management plane M-Plane message, so that the DU is aware of its capabilities.

[0030] When the DU system or its upper-level management software determines, based on preset strategies such as current time-period traffic prediction and the power supply status of the RRU's location, that a specific RRU needs to be placed in a low-power state, the control flow of this implementation method is triggered. The DU encapsulates a specific M-Plane message, which is sent to the target RRU through the standard eCPRI fronthaul interface. This message is encapsulated using configuration protocols such as NETCONF, and the most critical information in it is the specific low-power level instruction required for the RRU, such as instructing it to enter SM4-L2 level.

[0031] After receiving this M-Plane message from the DU, the eCPRI interface module on the RRU side parses it and extracts the low-power level control word. The main control logic on the RRU is implemented by the service FPGA or a dedicated processor. After recognizing the instruction, it starts the corresponding power management mechanism according to different levels; if the instruction requires entering the ultra-low power level, the power management process enters the core stage.

[0032] In this embodiment, the RRU will perform power management operations at this time. For example... Figure 4 As shown, the main control logic of the RRU quickly cuts off the power supply to multiple circuits by controlling a series of power enable signals. These circuits whose power supply is cut off typically include power amplifier circuits, various radio frequency circuits, clock circuits that provide the operating clock for digital chips, and most of the digital processing circuits.

[0033] Combination Figure 4 As illustrated in this embodiment, if the received low-power level is SM4-L0, the service FPGA will power down the power amplifier circuit and RF circuit by controlling the power enable signal 3. eCPRI communication is normal in this mode. The DU and RU can exchange messages normally via M-Plane.

[0034] If the received low-power level is SM4-L1, the power amplifier and RF circuits are first powered down via control power enable signal 3, and then the RFSOC circuit in the service FPGA is powered down via control power enable signal 2. eCPRI communication is normal in this mode. DU and RU can exchange messages normally via M-Plane.

[0035] If the received low power level is SM4-L2, it indicates that you need to enter the ultra-low power mode. The specific processing steps are as follows: The business FPGA controls the power supply enable signal 3 to power off the power amplifier and RF circuit. The business FPGA controls the power supply enable signal 2 to power down the RFSOC circuit in the FPGA; The business FPGA sends a power-down command to the MCU via the UART communication serial port; After receiving the power-down command, the MCU controls the power supply enable signal 1 to complete the power-down of the 5V 4 bus power supply.

[0036] Since the digital circuits, clock circuits, and FPGA power supply circuits all use the 5V4 bus power supply as input, when the 5V4 bus power is lost, the digital circuits, clock circuits, and service FPGA circuits are all powered down, resulting in extremely low standby power consumption. Simultaneously, the auxiliary 3V3 power supply circuit ensures continuous power supply to the MCU circuit and a specific optical port. The MCU selected is a low-power model, such as AI8H2K32U or STM32L0, which has extremely low power consumption in standby mode, meeting the requirements for long-term low-power operation. The reserved optical port is connected to the MCU through a specific circuit and uses a special method to interact with the DU. In this embodiment, the circuit related to this optical port can be related to basic physical layer components such as laser driver and receiver photoelectric conversion. Through this power-off strategy, the overall standby power consumption of the RRU is controlled at an extremely low level, preferably not exceeding 5 watts, thus achieving significant energy-saving effects.

[0037] After the RRU enters the aforementioned ultra-low power mode, the normal service data channel and higher-layer signaling channel between it and the DU via the eCPRI interface are interrupted due to the power loss of the digital circuit. In order to maintain the DU's basic awareness of the RRU's status and retain the ability to remotely wake up, this embodiment designs an out-of-band communication mechanism based on optical port physical layer control signals.

[0038] In this embodiment, the key to the out-of-band communication mechanism lies in the reuse of existing control pins on the optical module and the universal asynchronous serial protocol, which can be viewed synchronously. Figure 5 The communication process architecture is illustrated below. Specifically, on the RRU side, the MCU, which remains operational, undertakes the task of communication in low-power mode. The MCU encapsulates the status information (including "entered super low power," "hardware status normal," etc.) that needs to be reported to the DU into a binary data stream according to the UART protocol frame format. Then, instead of sending this information through the regular data channel, the MCU simulates UART communication by controlling the level changes of the TX_DISABLE pin on its local optical module. The TX_DISABLE pin is originally used to forcibly disable the laser emission function of the optical module. By programming and controlling the duration of the high and low levels of this pin, a specific pulse sequence representing the start bit, data bit, and stop bit in the UART protocol can be formed, thereby "modulating" the encapsulated status information onto the TX_DISABLE signal.

[0039] On the DU side, in order to receive the information reported by the RRU in this special way, the DU continuously monitors the status of the RX_LOS pin of its corresponding optical module. The RX_LOS pin becomes active when the optical module does not receive a valid optical signal. When the RRU's MCU transmits information by manipulating TX_DISABLE, it causes the optical power output by the RRU optical module to change regularly or be intermittently interrupted. This change is detected by the optical module on the DU side and reflected as a synchronous change sequence of the RX_LOS pin level. The monitoring logic on the DU side captures this RX_LOS signal sequence and demodulates and decodes it according to the same UART protocol specification, thereby reconstructing the status information sent by the RRU. This implementation method enables the DU to still obtain the status report when the RRU is in ultra-low power mode and the service channel is interrupted, ensuring that the status reporting function is unaffected.

[0040] When network conditions change, such as increased traffic requiring the RRU to resume service, the DU needs to command the RRU to exit ultra-low power mode. The exit procedure can be found in [link to documentation]. Figure 6 The diagram illustrates this. The wake-up command is sent using the same reverse physical link as the status reporting. The controller on the DU side encapsulates the command to exit low-power mode into a data frame according to the UART protocol. Then, the DU sends out this command sequence by controlling the level change of its own optical module's TX_DISABLE pin. Correspondingly, the physical layer of the optical port on the RRU side, when in active state, always maintains the ability to detect received light. The RRU's MCU continuously monitors the RX_LOS pin of its local optical module. When the DU sends a wake-up command causing a change in the optical signal, the RX_LOS pin generates a corresponding level sequence. The RRU's MCU captures this sequence and parses the control commands contained within it using the UART protocol.

[0041] Once the RRU's MCU confirms that the parsed command is a valid exit instruction, it will immediately initiate the exit process. The MCU first controls the power management circuit to restore power to each circuit in a predetermined order. In this embodiment, this order is designed to ensure stable system startup; for example, power is restored to the clock circuit and core digital logic circuit first, then the RF circuit after initialization, and finally the power amplifier circuit. During the entire power restoration process, each hardware module of the RRU is sequentially powered on and initialized. Once all necessary circuits are back to normal operation, the RRU will re-establish a complete eCPRI connection with the DU, synchronize system parameters, and quickly return to a state capable of handling wireless communication services. At this point, the entire process of waking up from ultra-low power mode and restoring service is complete.

[0042] In this embodiment, combined with Figure 4Power management architecture and Figure 6 The entire process of restoring normal power supply can be carried out as follows: The control module inside the DU encodes the control command for the RRU to exit low-power mode according to the UART protocol, controls the level of the TX_DISABLE signal, and controls the optical power of the DU's optical module. After receiving the optical signal from the DU, the optical module on the RRU side generates a corresponding RX_LOS signal based on the optical power and transmits it to the MCU. The MCU parses the signal according to the UART protocol and extracts the instruction to exit ultra-low power mode. After confirming that the instruction is correct, the MCU restores the power supply to the 5V4 bus by controlling the power supply enable signal 1. Power enable signals 2 and 3 are pulled up to the 5V4 bus in hardware. When the 5V4 bus is restored to power, they are automatically pulled high, thereby restoring power to the power amplifier circuit, RF circuit, RFSOC circuit, digital circuit, and clock circuit. Because the default I / O state of the service FPGA is high impedance when it is not configured, and the default I / O state is high after the service FPGA is configured, this will not affect the level state of power enable signals 2 and 3. The MCU controls the electronic switch, changing the TX_Disable signal of the optical module from MCU control to service FPGA control; The FPGA completes power-on and initialization, the eCPRI interface recovers, and the DU and RU exchange messages normally via M-Plane. At this point, the low-power exit process is complete.

[0043] To ensure the reliability and stability of the entire method, corresponding protection and verification mechanisms are implemented at each stage. For example, during command transmission, the eCPRI protocol itself has data verification functionality to ensure the accuracy of M-Plane message transmission; during UART communication, methods such as reducing the UART rate and parity checking are used to ensure the correctness of status information and control command transmission; the power management circuit has overvoltage and overcurrent protection functions to prevent damage to the internal circuitry of the RRU during power switching. Furthermore, in terms of hardware layout, the internal circuit board of the RRU adopts a multi-layer wiring design, rationally planning power and signal lines to reduce electromagnetic interference. The MCU and optical module are placed as close as possible to shorten signal transmission distance and reduce signal attenuation and interference.

[0044] The above-described method of this embodiment can therefore be implemented in an RRU low-power control system, which preferably includes the following functional units: The message transmission and control unit, deployed on the distributed unit (DU) side, is used to send management plane M-Plane messages carrying target low power level information to the remote radio frequency unit (RRU) via the eCPRI fronthaul interface. It is also used to generate and send instructions to exit low power mode when needed. The power management and execution unit, deployed on the RRU side, is communicatively connected to the message transmission and control unit. It is used to respond to and parse the M-Plane message and perform corresponding power management operations according to the parsed low power level. The power management operations include cutting off the power supply to the power amplifier circuit, radio frequency circuit, clock circuit and main digital circuit, while maintaining the microcontroller unit (MCU) and at least one optical port in the working state. A low-power state interaction unit, deployed on the RRU side and the DU side, is used to establish and maintain an out-of-band communication link based on the optical port physical layer control signal after the RRU enters low-power mode. The low-power state interaction unit includes: an encoding module for encapsulating state information or control commands according to the Universal Asynchronous Receiver Transmitter (UART) protocol, and a physical signal modulation and demodulation module for transmitting the encapsulated information by controlling the optical module to transmit a TX_DISABLE signal or monitoring the received signal loss RX_LOS signal. An exit control and recovery unit, deployed on the RRU side, is connected to the low-power state interaction unit and the power management and execution unit. It is used to monitor and parse exit commands from the DU through the out-of-band communication link, and after parsing the exit command, trigger the power management and execution unit to restore the power supply of the circuits that have been cut off according to a predetermined sequence and process, so that the RRU exits the low-power mode and resumes normal operation.

[0045] Therefore, this invention achieves low-power control of RRU mainly through software logic and protocol innovation on the basis of existing ORAN hardware. It has the advantages of low cost and easy deployment, while resolving the contradiction between deep energy saving and flexible wake-up.

Claims

1. A low-power control method for RRUs based on ORAN, characterized in that, The method includes the following steps: S1. The distributed unit (DU) sends a management plane M-Plane message to the remote radio unit (RRU) through the fronthaul interface, instructing the RRU to enter the target low-power mode. S2. In response to the M-Plane message, the RRU performs a power management operation to enter the target low-power mode; wherein, the power management operation includes cutting off the power supply to unnecessary circuits and maintaining the microcontroller unit (MCU) and at least one optical port in an active state. S3. In the target low-power mode, the MCU of the RRU and the DU interact based on the physical layer control signal of the optical port and follow a predetermined communication protocol to maintain the status monitoring and control link of the RRU. S4. When the RRU needs to exit the target low-power mode, the DU sends an exit command to the RRU through the physical layer control signal and the predetermined communication protocol. S5. After monitoring and parsing the exit instruction, the MCU of the RRU controls the restoration of power supply to the non-essential circuits so that the RRU exits the target low-power mode and resumes normal operation.

2. The RRU low-power control method according to claim 1, characterized in that, In step S1, instructing the RRU to enter the target low-power mode specifically includes: the DU sending the M-Plane message to the RRU through the eCPRI fronthaul interface, the M-Plane message being encapsulated using the NETCONF protocol; the M-Plane message containing control information indicating the target low-power level that the RRU enters, the target low-power level including at least one ultra-low power level.

3. The RRU low-power control method according to claim 2, characterized in that: The target low power level is defined by a set of low power levels supported in a predefined configuration data model of the RRU; wherein the set of low power levels includes at least the super low power level, which is configured to disconnect power to circuits other than the microcontroller unit (MCU) and the at least one optical port upon entry.

4. The RRU low-power control method according to claim 3, characterized in that: When the target low power level is the super low power level, the total power consumption of the RRU after entering the target low power mode is controlled to not exceed 5 watts.

5. The RRU low-power control method according to claim 1, characterized in that, In step S2, the power management operation includes cutting off the power supply to non-essential circuits, specifically cutting off the power supply to the power amplifier circuit, radio frequency circuit, clock circuit, and main digital circuit inside the RRU; wherein, the main digital circuit does not include the microcontroller unit (MCU) and the interface circuit directly related to the operation of the at least one optical port.

6. The RRU low-power control method according to claim 1, characterized in that, In step S3, interaction is performed based on the physical layer control signal of the optical port and in accordance with a predetermined communication protocol. Specifically, this includes: the MCU of the RRU and the DU control the transmission disable TX_DISABLE signal and monitor the loss of received signal RX_LOS signal of their respective optical modules, and encapsulate and parse the interactive information using the Universal Asynchronous Receiver / Transmitter (UART) protocol, thereby realizing bidirectional communication.

7. The RRU low-power control method according to claim 6, characterized in that, In the target low-power mode, the process of maintaining the status monitoring and control link between the MCU of the RRU and the DU specifically includes: the MCU of the RRU encapsulates the status information into a first control sequence according to the UART protocol, and sends the first control sequence to the DU by controlling the change of the TX_DISABLE signal of the local optical module; the DU obtains the first control sequence by monitoring the change of the RX_LOS signal of its optical module, and parses the current status information of the RRU according to the UART protocol.

8. The RRU low-power control method according to claim 6, characterized in that, In step S4, the DU sends an exit command to the RRU through the physical layer control signal and the predetermined communication protocol. Specifically, the DU encapsulates the exit control command into a second control sequence according to the UART protocol, and sends the second control sequence to the RRU by controlling the change of the TX_DISABLE signal of its own optical module. The MCU of the RRU obtains the second control sequence by monitoring the change of the RX_LOS signal of its own optical module, and parses the exit control command according to the UART protocol as the exit command.

9. The RRU low-power control method according to claim 1, characterized in that, In step S5, after the RRU's MCU detects and parses the exit instruction, it controls the restoration of power supply to the non-essential circuits. Specifically, the RRU's MCU first restores power supply to the clock circuit and circuits related to the main digital functions; after completing the above power restoration and confirming that the relevant circuits have been initialized, it then restores power supply to the RF circuit and power amplifier circuit in sequence. The process and sequence of power restoration are controlled by the preset power management logic within the RRU.

10. A low-power RRU control system implementing the method of any one of claims 1-9, characterized in that, The system includes the following functional units: The message transmission and control unit, deployed on the distributed unit (DU) side, is used to send management plane M-Plane messages carrying target low power level information to the remote radio frequency unit (RRU) via the eCPRI fronthaul interface. It is also used to generate and send instructions to exit low power mode when needed. The power management and execution unit, deployed on the RRU side, is communicatively connected to the message transmission and control unit. It is used to respond to and parse the M-Plane message and perform corresponding power management operations according to the parsed low power level. The power management operations include cutting off the power supply to the power amplifier circuit, radio frequency circuit, clock circuit and main digital circuit, while maintaining the microcontroller unit (MCU) and at least one optical port in the working state. A low-power state interaction unit is deployed on the RRU side and the DU side to establish and maintain an out-of-band communication link based on the optical port physical layer control signal after the RRU enters the low-power mode. The low-power state interaction unit includes: an encoding module for encapsulating state information or control commands according to the Universal Asynchronous Receiver / Transmitter (UART) protocol, and a physical signal modulation and demodulation module for transmitting the encapsulated information by controlling the optical module to transmit a TX_DISABLE signal or monitoring a lost RX_LOS signal. An exit control and recovery unit, deployed on the RRU side, is connected to the low-power state interaction unit and the power management and execution unit. It is used to monitor and parse exit commands from the DU through the out-of-band communication link, and after parsing the exit command, trigger the power management and execution unit to restore the power supply of the circuits that have been cut off according to a predetermined sequence and process, so that the RRU exits the low-power mode and resumes normal operation.

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