JP5309052B2 - Radio base station apparatus and communication processing control method in radio base station apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve low power consumption and to take a countermeasure against heat effectively by controlling power consumption of a multi-core processor which performs communication processing of a base station. <P>SOLUTION: One or more multi-core processors having a plurality of processor cores each capable of switching the operation mode independently is mounted in the baseband unit of a base station, wherein the multi-core processor has a program which defines the plurality of processor cores as Static cores or Dynamic cores, and a way for determining the numbers of the Static cores and Dynamic cores. The multi-core processor determines the numbers of the Static cores and Dynamic cores to be assigned, defines the Static core and Dynamic core, and sets the sleep mode or stand-by mode for the processor core which is assigned neither to the Static core nor the Dynamic core. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a radio base station apparatus that transmits / receives radio signals to / from a radio mobile station apparatus and a communication processing control method in the radio base station apparatus.

  In a wireless communication system, a wireless base station device and a wireless mobile station device are connected by a physical channel via a physical layer. Until now, processing of a physical layer (PHY: Physical Layer) in a radio base station apparatus has been realized by hardware by being mounted on an FPGA (Field Programmable Gate Array), an ASIC (Application Specific Integrated Circuit), or the like. Recently, however, there have been many cases where it is implemented in software by being mounted on a processor such as DSP (Digital Signal Processing).

  Furthermore, compared to a wireless base station apparatus of W-CDMA (Wideband-Code Division Multiplex Access) or CDMA2000 (Code Division Multiplex Access 2000) which is a method used in an existing system, LTE in which a service is newly started In the case of (Long Term Evolution) and mobile WiMAX (World interoperability for Microwave Access), the processing of the physical layer and scheduler performed by the radio base station apparatus is greatly increased. For example, the outline of the LTE physical layer and scheduler processing is described in Non-Patent Document 1 and Non-Patent Document 2.

For this reason, when implementing the physical layer and scheduler processing in software using a processor such as a DSP in an LTE or WiMAX radio base station, multiple processors are used because the amount of processing is insufficient with one processor. It is necessary to implement with a multiprocessor.
Japanese Patent Laid-Open No. 2004-228561 reduces the processing load and performs flexible communication corresponding to the bit rate and the number of sectors in the processing of the physical layer and scheduler in HSDPA (High Speed Downlink Packet Access) by considering the characteristics of the processing amount. The present invention aims to provide a processing method. In Patent Document 1, a scheduler function whose processing amount is proportional to the number of users and a line termination processing function whose processing amount is proportional to the data amount are provided in the same processing unit, and are controlled to be switched and executed in a preset time domain. This reduces the processing load on the processing unit. In the case of realization with multi-processing units, according to the processing load of each processing unit, by assigning users so that the processing load of all processing units is uniform, the processing impossible is made uniform, and the number of users that can be accommodated This increases the number of parts and enables a reduction in the number of parts.

On the other hand, recently, a multi-core processor in which a plurality of processor cores (hereinafter referred to as cores) are mounted in one processor chip has attracted attention. A general processor is a single-core processor in which one core composed of an instruction issuer, an arithmetic unit, and the like is mounted in one chip, whereas a multi-core processor is a plurality of cores in one chip. The core is installed. Since each core of a multi-core processor is basically independent, each core can operate without being affected by other cores, and increasing the number of cores installed can improve processor performance. it can.
Conventionally, processors have improved performance by increasing the operating clock frequency. However, due to the stagnation in the development of technology that increases the operating clock frequency and the increase in power consumption that accompanies the increase in operating clock frequency, improvement in performance with multi-core technology is becoming the mainstream. . Some multi-core processors have a sleep mode function for stopping an operation clock independently for each core and a standby mode function for stopping power supply for the purpose of reducing power consumption and heat.

  In an LTE or WiMAX radio base station apparatus, when layer 2 processing and layer 3 processing are further added to the physical layer and scheduler processing, in order to realize them with software, a high-performance core having an operating frequency of about 1 GHz is required. It is assumed that multiple multi-core processors with up to 6 are required.

JP 2008-99079 A

3GPP TS 36.211 V9.0.0 (2009-12) p9-p13, p42-p46 3GPP TS 36.213 V9.0.1 (2009-12) p18-p26, p54-p57

  As described above, when realizing the physical layer, scheduler processing, layer 2 processing, and layer 3 processing of LTE and WiMAX radio base station apparatuses with a multi-core processor, 4 to 6 high-performance cores with an operating frequency of about 1 GHz Multiple installed multi-core processors are required. The power consumption of the base band unit (BBU: Base Band Unit) of the radio base station apparatus is large because of the power consumption of the plurality of multi-core processors, and studies for reducing the power consumption of the multi-core processors are essential. . In addition, the BBU must be naturally air-cooled due to the limitation of the installation location, and the power consumption of the multi-core processor is required to reduce heat. In order to reduce the power consumption of the multi-core processor, a control technique that effectively uses the sleep mode function and the standby mode function is required.

  The present invention relates to a radio base station apparatus and a radio base station apparatus capable of controlling power consumption of a multi-core processor, effectively reducing power consumption, and taking measures against heat when performing communication processing using a multi-core processor. An object of the present invention is to provide a communication processing control method.

  The present invention has been made in order to solve the above-described problem, and the baseband unit includes one or more multi-core processors each having a plurality of processor cores each having a function of independently switching the operation mode. In the radio base station apparatus, the multi-core processor has a program for defining a plurality of processor cores as a static core or a dynamic core and means for determining the number of static cores and dynamic cores, and assigns static cores and dynamic cores. Determine the number, define the static and dynamic cores for multiple processor cores, and enter sleep mode for processor cores that are not assigned to either the static or dynamic core The other is obtained by to set in standby mode.

  According to the present invention, when communication processing is performed using a multi-core processor, the power consumption of the multi-core processor can be finely managed to effectively reduce power consumption and take measures against heat.

It is the figure which showed the structural example of the radio | wireless communication network. It is the figure which showed the structure of the wireless base station apparatus in one Embodiment of this invention. It is the figure which showed the structure of the layer 1 of the baseband part in one Embodiment of this invention. It is the figure which showed the basic structural example of the multi-core processor. It is the figure which showed an example of the usage rate and power consumption of each core in a multi-core processor. It is the figure which showed an example of the usage rate and power consumption of each core in a multi-core processor. It is the table which showed an example of the required number of cores computed based on the system band of a wireless base station apparatus, and the number of antennas. It is the table which showed an example of the required number of cores with respect to the number of radio | wireless mobile station apparatuses connected to a radio base station apparatus, and a transmission rate. It is the figure which showed the structure of the multi-core processor in one Embodiment of this invention. It is the flowchart which showed the processing content from power activation of the radio | wireless base station apparatus in one Embodiment of this invention to operation start. It is the flowchart which showed the processing content in operation | movement of the radio base station apparatus in one Embodiment of this invention.

DESCRIPTION OF EMBODIMENTS Embodiments for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a configuration example of a wireless communication network.
As shown in FIG. 1, the wireless communication network includes, for example, a plurality of wireless base station devices 1 to 3 (only three stations are shown in FIG. 1), a mobility management entity device (MME device: Mobility Management Entity) 4, and a gateway device. (GW device: GateWay) 5, operation and maintenance device (O & M device: Operation & Maintenance) 6, and network 7.
The radio base station apparatuses 1 to 3 perform transmission / reception with radio mobile station apparatuses located in a cell that is a radio wave reachable range of each radio base station apparatus. The MME device 4 manages mobility by handover of the radio mobile station device. The GW apparatus 5 routes and transfers user data packets. The O & M device 6 has a function of setting, controlling and monitoring system parameters mainly for the radio base station devices 1 to 3. The network 7 is mainly constructed by Ethernet (registered trademark). The radio base station apparatuses 1 to 3 and the radio mobile station apparatus located in the cell of each radio base station apparatus communicate with each other while being managed and controlled by the MME apparatus 4, the GW apparatus 5, and the O & M apparatus 6.

FIG. 2 shows the configuration of a radio base station apparatus according to an embodiment of the present invention.
The radio base station apparatus 1 includes an antenna 10, a radio frequency unit (RF unit: Radio Frequency) 20, and a baseband unit (BB unit: BaseBand) 30. The BB unit 30 is subdivided into a layer 1 unit 40, a layer 2 unit 50, and a layer 3 unit 60. Note that the RF unit 20 and the BB unit 30 may be configured as separate units as the RF unit and the BB unit so that they can be installed in different places.

The operation of each unit of the radio base station apparatus will be described.
The transmission packet 11 sent from the upper layer is input to the layer 3 unit 60 of the BB unit 30. Here, the upper layer corresponds to the MME device 4, the GW device 5, and the O & M device 6 connected to the network 7. The transmission packet 11 input to the layer 3 unit 60 is subjected to radio resource control (RRC) processing to become transmission data 12. The transmission data 12 output from the layer 3 unit 60 is input to the layer 2 unit 50.
The transmission data 12 input to the layer 2 unit 50 includes packet data convergence protocol processing (PDCP: Packet Data Convergence Protocol), radio link control (RLC: Radio Link Control), and media access control (MAC: Media Access Control). Processing is performed and transmission data 13 is obtained. The transmission data 13 output from the layer 2 unit 50 is input to the layer 1 unit 40.
The transmission data 13 input to the layer 1 unit 40 is subjected to physical layer processing and scheduler processing to become transmission data 14. The transmission data 14 output from the layer 1 unit 40 is input to the RF unit 20. The transmission data 14 input to the RF unit 20 is subjected to D / A conversion, IQ orthogonal modulation, frequency up-conversion, band limitation, and power amplification processing, and is transmitted as a radio signal 15 through the antenna 10.

On the other hand, the radio signal 15 input through the antenna 10 is input to the RF unit 20.
The radio signal 15 output from the antenna 10 is subjected to transmission, reception separation (TX / RX separation), low noise amplification, band limitation, frequency down-conversion, gain adjustment, IQ orthogonal demodulation, A / D conversion by the RF unit 20. Processing is performed to obtain received data 16.
The reception data 16 output from the RF unit 20 is input to the layer 1 unit 40 of the BB unit 30. The reception data 16 input to the layer 1 unit 40 is subjected to physical layer reception processing to become reception data 17. The reception data 17 output from the layer 1 unit 40 is input to the layer 2 unit 50. The reception data 17 input to the layer 2 unit 50 is subjected to MAC, RLC, and PDCP reception processing to become reception data 18. The reception data 18 output from the layer 2 unit 50 is input to the layer 3 unit 60. The reception data 18 input to the layer 3 unit 60 is subjected to RRC reception processing to become a reception packet 19. The received packet 19 output from the layer 3 unit 60 is transmitted to the upper layer.

FIG. 3 shows the configuration of the layer 1 part of the baseband part in one embodiment of the present invention.
The layer 1 unit 40 of the BB unit 30 includes an Inverse Fast Fourier Transform (IFFT) 405, a CPRI (Common Public Radio Interface) transmission process 406, a CPRI reception process 407, an FFT process 408, an O & M interface process 440, A data channel transmission process 450, a control channel transmission process 460, a data channel reception process 470, a control channel reception process 480, and a scheduler process 490 are included.
The data channel transmission process 450 includes an encoding process 401, a scramble process 402, a modulation process 403, and a mapping process 404.
The control channel transmission process 460 includes an encoding process 413, a scramble process 414, a modulation process 415, and a mapping process 416.
The data channel reception process 470 includes a demapping process 409, a demodulation process 410, a descrambling process 411, and a decoding process 412.
The control channel reception process 480 includes a demapping process 417, a demodulation process 418, a descrambling process 419, and a decoding process 420.

  The transmission data 13 output from the layer 2 unit 50 is classified into transmission data 140 related to the data channel and transmission data 141 related to the control channel. The transmission data 140 related to the data channel is controlled by the encoding process 401 of the data channel transmission process 450. The transmission data 141 regarding the channel is input to the encoding process 413 of the control channel transmission process 460, respectively.

Transmission data 140 input to the encoding process 401 is subjected to error detection / error correction encoding such as a cyclic redundancy check (CRC) code, a Viterbi code, and a turbo code, and becomes transmission data 130. The transmission data 130 output from the encoding process 401 is input to the scramble process 402.
The transmission data 130 input to the scramble process 402 is scrambled based on a predetermined rule to become transmission data 131. The transmission data 131 output from the scramble process 402 is input to the modulation process 403.
The transmission data 131 input to the modulation processing 403 is subjected to modulation such as quadrature phase shift keying (QPSK) and 16-value quadrature amplitude modulation (16QAM) to become transmission data 132. . The transmission data 132 output from the modulation process 403 is input to the mapping process 404.
The transmission data 132 input to the mapping process 404 is subjected to layer mapping, precoding, and radio resource mapping to become transmission data 133.

The transmission data 141 related to the control channel input to the control channel transmission processing unit 460 is also subjected to the same encoding process 413, scrambling process 414, modulation process 415, and mapping process 416 as the transmission data 140 related to the data channel. The transmission data 133 output from the mapping process 404 and the transmission data 138 output from the mapping process 416 are input to the IFFT process 405.
The transmission data 133 and 138 input to the IFFT processing 405 are subjected to inverse Fourier transform and processing for adding a most click prefix (CP) to become transmission data 134. The transmission data 134 output from the IFFT process 405 is input to the CPRI transmission process 406.
The transmission data 134 input to the CPRI transmission processing 406 is converted into the transmission data format of the CPRI standard interface and becomes the transmission data 14.

On the other hand, the reception data 16 output from the RF unit 20 is input to the CPRI reception processing 407. The received data 16 input to the CPRI receiving process 407 is extracted from the CPRI standard interface and becomes the received data 160. The reception data 160 output from the CPRI reception process 407 is input to the FFT process 408.
The received data 160 input to the FFT processing 408 is subjected to CP deletion and Fourier transform to become received data 161. The received data 161 output from the FFT processing 408 is input to the demapping processing 409 of the data channel reception processing unit for the reception data 161 related to the data channel, and to the demapping processing 417 of the control channel reception processing 480 for the reception data 165 related to the control channel. Is done.

The reception data 161 input to the demapping process 409 is subjected to inverse processing for radio resource mapping, inverse processing for precoding, and inverse processing for layer mapping, and becomes reception data 162. The reception data 162 output from the demapping process 409 is input to the demodulation process 410.
The received data 162 input to the demodulation process 410 is subjected to demodulation such as Minimum Mean Square Error (MMSE) demodulation and Maximum Likelihood Detection (MLD) demodulation to be received data 163. The reception data 163 output from the demodulation process 410 is input to the descrambling process 411.
The reception data 163 input to the descrambling process 411 is subjected to a descrambling process based on a predetermined rule, and becomes reception data 164. The reception data 164 output from the descrambling process 411 is input to the decoding process 412.
Received data 164 input to decoding process 412 is subjected to error detection and error correction processes such as CRC decoding, Viterbi decoding, and turbo decoding to become received data 142.

The received data 165 related to the control channel input to the demapping process 417 of the control channel reception processing unit 480 is also the same demapping process 417 and demodulation process 418 as the received data 161 related to the data channel input to the data channel reception processing unit 470. The descrambling process 419 and the decoding process 420 are performed, and the received data 143 is obtained.
The reception data 142 output from the decoding process 412 and the reception data 143 output from the decoding process 420 are integrated into one reception data 17 and input to the layer 2 unit 50.

The O & M interface processing 440 manages interface processing with the O & M device, and has a system parameter setting function, a monitoring function, and other control functions.
The scheduler process 490 controls radio mobile station apparatus selection, radio resource allocation, power control, and the like, and the processing amount is proportional to the number of radio mobile station apparatuses to be connected.

  Hereinafter, the method of the present invention for allocating the processing of the layer 1 unit 40 to the multi-core processor will be described with specific examples.

FIG. 4 shows a basic configuration example of the multi-core processor.
FIG. 4 is a configuration example of a multi-core processor when 6 cores are mounted.
The multi-core processor 301 includes a core 3010, a core 3011, a core 3012, a core 3013, a core 3014, a core 3015, a variable voltage control unit 3016, and a variable clock frequency control unit 3017.
In this embodiment, in FIG. 4, the IFFT processing 405, CPRI transmission processing 406, CPRI reception processing 407, FFT processing 408, O & M interface processing 440, control channel transmission processing 460, and control channel reception processing 480 shown in FIG. (CORE1), core 3011 (CORE2), data channel transmission processing 450, data channel reception processing 470, and scheduler processing 490 are assigned to core 3012 (CORE3), core 3013 (CORE4), core 3014 (CORE5), and core 3015 (core 3015). The case of assignment to CORE6) will be described.

5 and 6 are diagrams showing an example of the usage rate and power consumption of each core of the multi-core processor during operation.
5 and 6 show examples of the utilization rate and power consumption of each core of the multi-core processor at a certain moment when processing is assigned to each core as described above and the radio base station apparatus is operated. Here, the usage rate indicates the ratio [%] of the number of used cycles required for actual calculation to the maximum number of cycles that the core can calculate. The power consumption indicates the ratio [%] of the power consumption at the time of calculation to the maximum power consumption of the core.
In the example illustrated in FIG. 5, the usage rate of each core of the multi-core processor is 70 to 80 [%]. The power consumption at that time is 90% or more for each core.

  On the other hand, in the example shown in FIG. 6, the usage rates of the CORE1 and CORE2 of the multi-core processor are 80 [%], but the usage rates of the CORE3, CORE4, CORE5, and CORE6 are 10 to 20 [%]. . In the example of FIG. 6, although the usage rate of CORE3, CORE4, CORE5, and CORE6 is 10 to 20%, the power consumption ratio is about 90% for CORE2, CORE3, CORE4, CORE5, CORE6 has a high value of about 70 to 80 [%].

That is, it can be seen that in a multi-core processor, even if the core usage rate is different, there is not much difference in power consumption. The reason why there is no significant difference in power consumption even when the usage rates of the respective cores of the multi-core processor are greatly different is considered to be that there is no difference in the power consumption of the processors due to the difference in instructions. For example, in a state where the core of the multi-core processor does not perform any particular operation, a NOP (No OPeration) instruction may be rotated in a loop. However, since the NOP instruction is not much different in power consumption compared to other addition instructions and multiplication instructions, the result is that there is no difference in core power consumption.
Therefore, in order to reduce the power consumption of the core, it is necessary to use a sleep mode function for stopping the operation clock and a standby mode function for stopping power supply for each core, rather than reducing the core usage rate.

During actual operation, a difference in operation time is assumed as a condition for the usage rate of each core of the multi-core processor to increase or decrease as in the example of FIG. 5 or FIG. For example, FIG. 5 may be a usage rate at 12:00 noon, and FIG. 6 may be a usage rate at midnight. At 12:00 noon and midnight, the number of radio mobile station devices connected to the radio base station device and the amount of traffic are greatly different. Therefore, it is assumed that the usage rate varies greatly even with the same radio base station. Depending on the region, the relationship of high usage at 12:00 and low usage at midnight may be reversed. In addition, it is assumed that the usage rate differs greatly not in time units but in day and date units. For example, on weekdays and holidays in a business district, the number of wireless mobile station devices connected to the wireless base station device and the amount of traffic are greatly different, and the usage rate is expected to change greatly.
Furthermore, the number of wireless mobile station devices to be connected and the amount of traffic are greatly different between the start of operation, months after the start of operation, and years later. Of course, it is assumed that the usage rate varies greatly in short time units. For example, when a large number of wireless mobile station apparatuses change the cell in which they are located by handover at the same time, it is assumed that the number of connected wireless mobile station apparatuses and the amount of traffic change greatly, and the usage rate also changes greatly. .

Also, it is assumed that the usage rate varies greatly depending on the installation location of the radio base station apparatus.
For example, a radio base station device installed in the city center always has a large number of connected radio mobile station devices and traffic volume, and a radio base station device installed in a suburb always has a small number of connected radio mobile station devices and traffic volume. Therefore, it is also assumed that the usage rate varies greatly between radio base apparatuses.

Although various assumptions for changing the core usage rate have been described above, it should be noted that, in the above-described assignment, CORE3, CORE4, CORE5, While the usage rate of CORE6 varies greatly, the usage rates of CORE1 and CORE2 are substantially the same.
In the following, a method for assigning processing to each core of a multi-core processor focusing on this point will be described. Here, a method of assigning the processing of the layer 1 unit 40 of the BB unit 30 to each core of the multi-core processor will be specifically described.

  First, in the embodiment of the present invention, a static core and a dynamic core are defined, and a plurality of cores in the multi-core processor are classified into a static core and a dynamic core. Here, the static core is a core that is always operated in the operation mode during operation. In addition, the Dynamic core is a core that appropriately shifts between an operation mode and a sleep mode or a standby mode during operation. The sleep mode means that the operation clock input to the core is stopped from the variable clock frequency control unit. The standby mode means that the power supply voltage input to the core is stopped from the variable voltage control unit. In the standby mode, power consumption can be significantly reduced as compared with the sleep mode, but the time for shifting to the operation mode increases.

Next, a method of allocating layer 1 processing to the static core and the dynamic core will be described.
The static core is assigned a process whose processing amount does not change greatly from the start of operation to the stop of operation, for example, a process related to the system band and the number of antennas, a process related to the control channel, and a process related to the interface with the O & M device. On the other hand, to the Dynamic core, processing whose processing amount greatly changes according to the number of connected wireless mobile station devices and the traffic amount, for example, processing related to a data channel, scheduler processing is allocated.
When the above allocation method is applied to the processing of the layer 1 unit 40 of the BB unit 30, the Static core includes the IFFT processing 405, the CPRI transmission processing 406, the CPRI reception processing 407, the FFT processing 408, the O & M interface processing 440 in FIG. Channel transmission processing 460 and control channel reception processing 480 are allocated. Data channel transmission processing 450, data channel reception processing 470, and scheduler processing 490 are allocated to the Dynamic core.

Next, a method for determining the number of cores of the static core and the dynamic core will be described.
The processing allocated to the static core largely depends on the processing amount mainly depending on the system band and the number of antennas. Therefore, the processing amount for the system band and the number of antennas is estimated in advance, and the necessary number of cores is obtained.
The processing allocated to the Dynamic core largely depends on the number of radio mobile station apparatuses and the transmission rate. Therefore, the number of radio mobile station apparatuses and the processing amount for the maximum transmission rate are estimated in advance, and the necessary number of cores is obtained.

FIG. 7 shows an example of the required number of cores calculated based on the system band of the radio base station apparatus and the number of antennas.
As shown in FIG. 7, for example, when the system band of the radio base station apparatus is 5 MHz and the number of antennas is 4, the number of static cores is 1, the system band of the radio base station apparatus is 10 MHz, and the number of antennas is 2 If the number of static cores is 1, the system band of the radio base station apparatus is 10 MHz, and the number of antennas is 4, the number of required cores is determined such that the number of static cores is 2. This table is stored in the multi-core processor.

FIG. 8 shows an example of the required number of cores calculated based on the number of radio mobile station apparatuses connected to the radio base station apparatus and the maximum transmission rate.
As shown in FIG. 8, for example, when there are 0 to 100 wireless mobile station devices connected to the wireless base station device, the maximum downlink transmission rate is 75 Mbps, and the maximum uplink transmission rate is 25 Mbps, the dynamic core is allocated. When the number of cores is 1, 0 to 100 wireless mobile station devices are connected to the radio base station device, the maximum downlink transmission rate is 150 Mbps, and the maximum uplink transmission rate is 50 Mbps, the number of cores allocated as the Dynamic core is 2 When 0 to 100 wireless mobile station devices are connected to the wireless base station device, the maximum downlink transmission rate is 150 Mbps, and the maximum uplink transmission rate is 75 Mbps, the number of cores allocated as the Dynamic core is 3, There are 101 to 200 wireless mobile station devices connected to the device, and the maximum downlink transmission rate is 150M. ps, if the uplink maximum transmission rate is 50Mbps, the number of cores assigned as Dynamic core prerequisite cores estimates and so 3, previously determined. This table is stored in the multi-core processor.

Next, an operation method of the static core and the dynamic core will be described.
FIG. 9 shows the configuration of a multi-core processor according to an embodiment of the present invention.
In FIG. 9, the same reference numerals as those in FIG. 4 are given.
Here, the number of multi-core processors is M, the number of cores per processor is L,
In FIG. 9, description will be made by taking M = 1 and L = 6 as an example. In the variable voltage control unit 3016 and the variable clock frequency control unit 3017 shown in FIG. 9, the power supply voltage VCC3018 and the operation clock CLK3019 can independently control the core 3010, core 3011, core 3012, core 3013, core 3014, and core 3015, respectively. And FIG. 9 shows an example in the case of Static core = 2 and Dynamic core = 3. Cores 3010 and 3011 are static cores, cores 3012 to 3014 are dynamic cores, and the remaining cores 3015 are input to the core. The standby mode is set in which the voltage is stopped from the variable voltage control unit.

FIG. 10 shows a flowchart of processing contents from when the radio base station apparatus is powered on until operation is started.
Specifically, it is a flowchart for explaining the contents of the core allocation process of the multi-core processor of the radio base station apparatus.
When the power is turned on, only the core 3010 starts the boot process. Here, the core 3010 is a core that performs management and control of the static core and the dynamic core. Note that the core 3010 is premised on the static core, and a pre-assigned processing program is selected to start the boot processing (S1001).
When the boot process is completed, the core 3010 enters an operation mode and waits for a system parameter setting (S1002). The system parameters are set from an external device via a network, and are configured with various parameters necessary for the operation of the radio base station device. The system parameters include, for example, supported bands, the number of antennas, the number of radio mobile station apparatuses, the maximum downlink transmission rate, and the maximum uplink transmission rate. The external device is, for example, the O & M device 6 shown in FIG.

The core 3010 includes the necessary number of static cores and dynamic cores shown in FIG. 7 and FIG. 8 as a table, and system parameters are set from an external device, and at the same time, the band included in the system parameters, the number of antennas, and the radio The number of cores ls required for the static core and the number of cores ld required for the dynamic core are obtained from the number of mobile station devices, the maximum downlink transmission rate, and the maximum uplink transmission rate (S1003). Here, the number of cores ld necessary for the Dynamic core means the maximum number of cores necessary to satisfy the number of radio mobile station apparatuses, the maximum downlink transmission rate, and the maximum uplink transmission rate.
For example, if the set system parameter includes a band = 10 MHz and the number of antennas = 4, the number of static cores ls = 2, the number of wireless mobile station devices = 100 based on FIG. 7, the downlink transmission rate = 150 Mbps, uplink transmission If the rate is 75 Mbps, the number of Dynamic cores is ld = 3 based on FIG.

  Next, the core 3010 indicates the number of static cores and the number of dynamic cores obtained from the band, the number of antennas, the number of radio mobile station apparatuses, the maximum downlink transmission rate, and the maximum uplink transmission rate included in the system parameters. 3013, core 3014, and core 3015 are defined. In the above example, when ls = 2 and ld = 3, the core 3010 and the core 3011 are defined as static cores, and the core 3012, the core 3013, and the core 3014 are defined as dynamic cores (S1004).

  Next, the core 3010 performs an IFFT process 405, a CPRI transmission process 406, a CPRI reception process 407, an FFT process 408, an O & M interface process 440, a control channel transmission process 460, shown in FIG. The program that controls the control channel reception process 480 is selected, and an instruction is given to start the boot process (S1005).

  The core 3011 enters the operation mode at the same time as the boot processing is completed, and the assigned processing can be started. The core 3010 is similar to the core 3011 in the IFFT processing 405, CPRI transmission processing 406, CPRI reception processing 407, FFT processing 408, O & M interface processing 440, control channel transmission processing 460, and control channel reception processing 480 shown in FIG. A program for controlling the process is included, and the same process as the core 3011 can be started. In addition, the core 3010 selects a program that controls the processing of the data channel transmission processing 450, the data channel reception processing 470, and the scheduler processing 490 shown in FIG. 3 for the core 3012, the core 3013, and the core 3014 defined as the dynamic core. Instructs to start the boot process. The core 3012, the core 3013, and the core 3014 enter the operation mode at the same time as the boot processing is completed, and the assigned processing can be started (S1006).

Next, the core 3010 is defined as a dynamic core for cores 3010 and 3011 defined as static cores, a core 3012 defined as a dynamic core, a core 3013, and an unused core other than the core 3014 (targeting the core 3015). However, it instructs to enter standby mode. The core 3015 instructed to enter the standby mode selects the program that controls the data channel transmission processing 450, the data channel reception processing 470, and the scheduler processing 490 shown in FIG. 3 in the same manner as the core defined as the Dynamic core. The boot process is started, but at the same time the boot process is finished, the standby mode is set. When shifting to the standby mode, the power supply voltage VCC3018 from the variable voltage control unit 3016 is stopped to enter the standby mode (S1007).
As described above, after all the sequences shown in FIG. 10 are completed, the operation of the layer 1 unit 40 allocated to the multi-core processor 301 is started.

During operation, the number of dynamic cores in the operation mode is dynamically changed according to the number of radio mobile station devices and traffic volume.
The number of Dynamic cores obtained from system parameters at the start of operation is the number of cores required for the maximum number of wireless mobile station devices and the maximum transmission rate, and the number of cores required according to the number of wireless mobile station devices actually connected and the traffic volume The number varies.
FIG. 11 shows a flowchart of processing contents of the multi-core processor of the operating radio base station apparatus.

  The core 3010 acquires the number U of radio mobile station apparatuses to be connected, the downlink transmission rate Rtx, and the uplink transmission rate Rrx from the upper layer (S1101).

  Next, the core 3010 obtains the necessary number of dynamic cores ld (t) using the evaluation function f (U, Rtx, Rrx) (S1102). The evaluation function f (U, Rtx, Rrx) is a function that receives the number of connected radio mobile station apparatuses U, the downlink transmission rate Rtx, and the uplink transmission rate Rrx, and outputs the number of dynamic cores necessary for the input. The method for obtaining the number of Dynamic cores is the same as in FIG. 8, and the number of Dynamic cores required for the combination of the assumed number of radio mobile station apparatuses U, downlink transmission rate Rtx, and uplink transmission rate Rrx is estimated in advance and converted into a function. Is. As another method for functionalization, a table in which the number of radio mobile station apparatuses, the downlink transmission rate, and the uplink transmission rate in FIG. 8 are further subdivided may be prepared.

When the latest value ld (t) of the evaluation function f is smaller than the previous value ld (t−T) (S1103), the number of dynamic cores in the operation mode is reduced, and unnecessary dynamic cores are selected from the dynamic cores in the operation mode. The number is shifted to the sleep mode (S1104).
The previous value ld (t−T) at the start of operation is a value obtained from the system parameters (in the above description, ld (t−T) = 3).
For example, when the latest value ld (t) = 2 of the evaluation function f, the previous value ld (t−T) = 3, and the core 3012, the core 3013, and the core 3014 are in the operation mode, the core 3014 in the operation mode is set to the sleep mode. A transition is made from the operation mode to the sleep mode with the dynamic core to be transferred.
When shifting from the operation mode to the sleep mode, after completing the data channel transmission processing or data channel reception processing and scheduler processing being processed, information such as registers is saved and the operation clock CLK 3019 from the variable clock frequency control unit 3017 is saved. The sleep mode is entered by stopping the operation.

On the other hand, if the latest value ld (t) of the evaluation function f is larger than the previous value ld (t−T) (S1106), the number of dynamic cores in the operation mode is added, and it is necessary from among the dynamic cores in the sleep mode. The number of dynamic cores is shifted to the operation mode (S1107).
For example, when the latest value ld (t) = 3 of the evaluation function f, the previous value ld (t−T) = 2, the core 3012 and the core 3013 are in the operation mode, and the core 3014 is in the sleep mode, the core 3014 in the sleep mode is The dynamic core that shifts to the operation mode is used, and the transition from the sleep mode to the operation mode is performed.
When shifting from the sleep mode to the operation mode, the operation mode is set by reading out information such as the saved registers and supplying the operation clock CLK 3019 from the variable clock frequency control unit 3017.
If the latest value ld (t) of the evaluation function f is equal to the previous value ld (t−T), the number of dynamic cores in the operation mode is not changed.

The change of the number of Dynamic cores as the operation mode is performed every update cycle T (S1105).
As described above, the power consumption is finely managed by dynamically controlling the number of dynamic cores in the operation mode based on the evaluation function f having the number of radio mobile station apparatuses U, the downlink transmission rate Rtx, and the uplink transmission rate Rrx as inputs. Therefore, power consumption that has been wasted can be reduced.

  In the above embodiment, the number of dynamic cores in the operation mode is determined by comparing the latest value ld (t) of the evaluation function f with the previous value ld (t−T) once. However, the latest value ld of the evaluation function f is determined. The operation is performed when the comparison result between (t) and the previous value ld (t−T) is N times consecutively, and the previous value ld (t−T) exceeds or falls below the latest value ld (t) of the evaluation function f. The number of dynamic cores in the mode may be determined. In addition, an average process may be performed on the comparison result between the latest value ld (t) and the previous value ld (t−T) of the evaluation function f, and the number of dynamic cores in the operation mode may be determined using the average value of the comparison result. Absent.

In the above embodiment, the description has been given of obtaining the number of dynamic cores ld in the operation mode at the start of operation from the system parameters set from the external device via the network. However, a method of programming in advance as a constant of the multi-core processor may be used. Absent.
In the above embodiment, the method of determining the number of dynamic cores ld in the operation mode during operation based on the evaluation function has been described, but a method of directly setting from an external device via a network may be used.
In the above embodiment, the update period T of the number of dynamic cores ld in the operation mode during operation may be set from an external device via a network, or may be programmed in advance as a constant of a multicore processor.

In the above embodiment, the number of multi-core processors is M = 1, and the number of cores per processor is L = 6. However, values other than M = 1 and L = 6 may be used.
For example, when M = 2 and L = 6, the core 3010 and the core 3011 in the first multi-core processor 301 are the static core, the core 3012, the core 3013, the core 3014, and the core 3015 are the dynamic cores in the operation mode. When the latest value ld (t) of the evaluation function f exceeds 4, if it is defined as a dynamic core in the second multi-core processor and a sleep mode core exists, the core is designated as the dynamic mode of the operation mode. A method of starting as a core can be considered.

In the above embodiment, the method of assigning the processing of the layer 1 unit 40 to each core of the multi-core processor has been described. However, it is of course possible to assign the processing of the layer 2 unit 50 and the layer 3 unit 60 to each core of the multi-core processor. It is.
As for the processing of the layer 2 unit 50 and the layer 3 unit 60, the dynamic core number ld (t) in the operation mode can be obtained using the evaluation function f (U, Rtx, Rrx) as in the case of the layer 1.
In addition, the scheduler process has been described as being included in layer 1, but may be included in layer 2 or handled as a single process.
Further, when the dynamic core in operation continues for a certain period of time, the sleep mode may be shifted to the standby mode.
In the above embodiment, when the number of Dynamic cores in the operation mode during operation is reduced, the transition to the sleep mode has been described. However, the standby mode may be used.
In the above embodiment, as a method for reducing the power consumption, the method of stopping the power supply voltage VCC and the operation clock CLK when shifting to the sleep mode or the standby mode has been described. However, if the power supply voltage is VCC, the voltage is lowered to a low voltage. Alternatively, if the operation clock CLK, a method of changing to a low frequency is also conceivable.

  In the above embodiment, the number of static cores is determined at the start of operation. However, if system parameters are reset from an external device via the network during operation, the number of static cores is changed. It doesn't matter.

1, 2, 3 ... Wireless base station apparatus, 4 ... MME apparatus, 5 ... GW apparatus, 6 ... O & M apparatus, 7 ... Network network, 10 antenna, 11 ... Transmission packet, 12, 13, 14 ... Transmission data, 15 ... Radio signal, 16, 17, 18 ... received data, 19 ... received packet, 20 ... RF part, 30 ... BB part, 40 ... layer 1 part, 50 ... layer 2 part, 60 ... layer 3 part, 130, 131, 132 133, 134, 140, 141 ... transmission data, 142, 160, 161, 162, 163, 164, 165 ... received data, 301 ... multi-core processor, 401 ... encoding process, 402 ... scramble process, 403 ... modulation process, 404 ... Mapping process, 405 ... IFFT process, 406 ... CPRI transmission process, 407 ... CPRI reception process, 408 ... FFT process, 409 ... hoax Ping processing, 410 ... demodulation processing, 411 ... descrambling processing, 412 ... decoding processing, 413 ... encoding processing, 414 ... scramble processing, 415 ... modulation processing, 416 ... mapping processing, 417 ... demapping processing, 418 ... demodulation processing 419 ... descrambling process, 420 ... decoding process, 440 ... O & M interface process, 450 ... data channel transmission process, 460 ... control channel transmission process, 470 ... data channel reception process, 480 ... control channel reception process, 490 ... scheduler process , 3010, 3011, 3012, 3013, 3014, 3015 ... processor core, 3016 ... variable voltage control unit, 3017 ... variable clock frequency control unit, 3018 ... power supply voltage VCC, 3019 ... operation clock CLK, 3020 ... sleep mode instruction.

Claims (10)

A radio base station device having a radio frequency unit for processing radio signals transmitted and received with a radio mobile station device, and a baseband unit,
The baseband unit is equipped with one or more multi-core processors each having a plurality of processor cores having a function of independently switching the operation mode,
The multi-core processor is defined as a static core for assigning a process with a small change in the amount of processing during operation of the radio base station apparatus to a plurality of processor cores, or a dynamic core for assigning a process with a large change in the amount of processing during operation. An allocation table for determining the number of static and dynamic cores based on program and system parameters for
When system parameters are set from an external device when the operation of the radio base station device is disclosed,
The multi-core processor refers to the table based on a set system parameter, determines the number of static cores and dynamic cores allocated, defines the static cores and the dynamic cores for the plurality of processor cores, A radio base station apparatus characterized in that those processor cores are set to a standby mode, and a processor core that is not assigned to either a static core or a dynamic core is set to a sleep mode.   The radio base station apparatus according to claim 1, wherein the number of static cores allocated is determined by a parameter including a system band of the radio base station apparatus and the number of antennas among the system parameters.   The radio base station apparatus according to claim 1, wherein the number of static cores and dynamic cores allocated is set from the external apparatus. A radio base station device having a radio frequency unit for processing radio signals transmitted and received with a radio mobile station device, and a baseband unit,
The baseband unit is equipped with one or more multi-core processors each having a plurality of processor cores having a function of independently switching the operation mode,
The multi-core processor is defined as a static core for assigning a process with a small change in the amount of processing during operation of the radio base station apparatus to a plurality of processor cores, or a dynamic core for assigning a process with a large change in the amount of processing during operation. And a program for determining the number of Dynamic cores based on parameters that change during operation and
During operation of the radio base station apparatus, the parameter is acquired at a predetermined update period, the number of Dynamic cores is determined based on the parameter, the number of Dynamic cores is increased / decreased with respect to the plurality of processor cores, and Static A radio base station apparatus, wherein a processor core that is not assigned to either the core or the Dynamic core is set in a sleep mode.   The radio base station apparatus according to claim 4, wherein the number of active Dynamic cores is set from an external apparatus.   The radio base station apparatus according to claim 4, wherein the update period is set from an external apparatus. The radio base station apparatus according to claim 4 , wherein the processor core set to the sleep mode controls the processor core to shift to the standby mode when the sleep mode continues for a certain period. The multi-core processor includes a variable voltage controller, a variable clock frequency control unit, the standby mode, instead of the sleep mode, wherein the stepping down the change or voltage the operating clock to the low-frequency low-voltage The radio base station apparatus according to claim 1. A multi-core processor control method for performing baseband processing in a radio base station apparatus having a radio frequency unit for processing radio signals transmitted to and received from a radio mobile station apparatus, and a baseband unit,
The baseband processing is realized by one or more multi-core processors each having a plurality of processor cores each having a function of switching operation modes independently.
The multi-core processor is defined as a static core for assigning a process with a small change in the amount of processing during operation of the radio base station apparatus to a plurality of processor cores, or a dynamic core for assigning a process with a large change in the amount of processing during operation. An allocation table for determining the number of static and dynamic cores based on program and system parameters for
When system parameters are set from an external device when the operation of the radio base station device is disclosed,
The multi-core processor refers to the table based on a set system parameter, determines the number of static cores and dynamic cores allocated, defines the static cores and the dynamic cores for the plurality of processor cores, A multi-core processor control method, wherein the processor cores are set to a standby mode, and a sleep mode is set for a processor core that is not assigned to either a static core or a dynamic core. A multi-core processor control method for performing baseband processing in a radio base station apparatus having a radio frequency unit for processing radio signals transmitted to and received from a radio mobile station apparatus, and a baseband unit,
The baseband processing is realized by one or more multi-core processors each having a plurality of processor cores each having a function of switching operation modes independently.
The multi-core processor is defined as a static core for assigning a process with a small change in the amount of processing during operation of the radio base station apparatus to a plurality of processor cores, or a dynamic core for assigning a process with a large change in the amount of processing during operation. And a program for determining the number of Dynamic cores based on parameters that change during operation and
During operation of the radio base station apparatus, the parameter is acquired at a predetermined update period, the number of Dynamic cores is determined based on the parameter, the number of Dynamic cores is increased / decreased with respect to the plurality of processor cores, and Static A control method for a multi-core processor, wherein a processor core that is not assigned to any of the core and the Dynamic core is set to a sleep mode.

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