WO2016002166A1 - 無線通信システム及び無線通信方法 - Google Patents
無線通信システム及び無線通信方法 Download PDFInfo
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- WO2016002166A1 WO2016002166A1 PCT/JP2015/003183 JP2015003183W WO2016002166A1 WO 2016002166 A1 WO2016002166 A1 WO 2016002166A1 JP 2015003183 W JP2015003183 W JP 2015003183W WO 2016002166 A1 WO2016002166 A1 WO 2016002166A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W72/00—Local resource management
- H04W72/04—Wireless resource allocation
- H04W72/044—Wireless resource allocation based on the type of the allocated resource
- H04W72/0446—Resources in time domain, e.g. slots or frames
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
- H04L1/0009—Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the channel coding
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
- H04L1/1867—Arrangements specially adapted for the transmitter end
- H04L1/1887—Scheduling and prioritising arrangements
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
- H04L27/2601—Multicarrier modulation systems
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L5/00—Arrangements affording multiple use of the transmission path
- H04L5/003—Arrangements for allocating sub-channels of the transmission path
- H04L5/0032—Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W72/00—Local resource management
- H04W72/20—Control channels or signalling for resource management
- H04W72/23—Control channels or signalling for resource management in the downlink direction of a wireless link, i.e. towards a terminal
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
- H04W88/08—Access point devices
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W92/00—Interfaces specially adapted for wireless communication networks
- H04W92/04—Interfaces between hierarchically different network devices
- H04W92/12—Interfaces between hierarchically different network devices between access points and access point controllers
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
- H04L27/2601—Multicarrier modulation systems
- H04L27/2602—Signal structure
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
- H04W88/02—Terminal devices
Definitions
- the present invention relates to a wireless communication system and a wireless communication method, and more particularly, to a wireless communication system and a wireless communication method configured by separating the function of a wireless base station into a wireless control device and a wireless device.
- Non-Patent Document 1 discloses a radio base station apparatus for an LTE (Long Term Evolution) system with a light-extending configuration.
- a wireless base station device digital processing unit BDE: Base Digital Processing Equipment
- RRE Remote Radio Equipment
- Non-Patent Document 3 discloses C-RAN (Radio Access Network).
- C-RAN is a transport network that has a wide bandwidth and low delay between DU cloud (DU: Digital Unit) installed on the center (core network, etc.) side and Radio Unit (RU) distributed at each antenna site. Connected and configured.
- DU cloud Digital Unit
- RU Radio Unit
- Non-Patent Document 1 the RRH-equipped radio device (RRE) only performs optical / electrical conversion and RF (Radio Frequency) functions, and other digital signal processing functions (error correction coding,
- the BDE executes radio framing, data modulation, frequency / time conversion, and MIMO (Multiple Input Multiple Output) processing).
- Non-Patent Document 2 discloses a configuration in which functions are shared.
- Patent Document 1 is premised on a network configuration in which a slave station is extended from a radio base station (master station), and can communicate with a master station device connected to a mobile communication network and a mobile communication terminal by radio.
- a digital fiber radio transmission system having one or a plurality of slave station devices and a transmission path connected between the master station device and each slave station device and capable of bidirectional digital transmission is disclosed.
- the signal processing circuit of the master station device remains a digital signal for the main signal (included in the transmission frame) communicated with the slave station device connected to the transmission control circuit.
- Signal processing such as signal demodulation, encoding / decoding, error detection / correction, line termination / demultiplexing according to the wireless system and protocol used is performed.
- antenna-side devices RRE, RE, slave station devices, etc.
- BDE center-side devices
- REC master station devices, etc.
- other digital signal processing is performed. Therefore, the transmission data rate between the center side device and the antenna side device is increased. Therefore, with the techniques of the above-described patent document and non-patent document, communication between the center side device (wireless control device) and the antenna side device (wireless device) cannot be performed efficiently.
- An object of the present invention is to solve such problems, and to provide a wireless communication system and a wireless communication method for efficiently performing communication between a wireless control device and a wireless device. .
- a wireless communication system includes a wireless control device and at least one wireless device that is connected to the wireless control device via a transmission line and performs wireless communication with a wireless terminal
- the wireless control device includes: Radio resource allocating means for allocating radio resources used when the radio apparatus performs radio communication with the radio terminal, and radio for transmitting an instruction to use the allocated radio resources to the radio apparatus Resource instruction means, and the wireless device performs wireless communication using the allocated wireless resource for data to be transmitted to the wireless terminal based on an instruction from the wireless control device
- a means for converting the signal processed by the wireless signal processing means into a wireless signal and transmitting the wireless signal to the wireless terminal.
- Another wireless communication system is provided between a wireless control device, at least one wireless device that performs wireless communication with a wireless terminal, and between the wireless control device and the wireless device.
- a relay apparatus connected to the apparatus via a first transmission path and connected to the radio apparatus via a second transmission path, wherein the radio control apparatus is configured such that the radio apparatus communicates with the radio terminal.
- the relay apparatus Based on an instruction from the radio control apparatus, the relay apparatus performs processing for performing radio communication on data to be transmitted to the radio terminal using the allocated radio resource.
- the wireless device a signal processed by said radio signal processing means is converted into a radio signal, and transmits to the wireless terminal.
- the wireless communication method includes a wireless control device connected to at least one wireless device that performs wireless communication with a wireless terminal via a transmission path, when the wireless device performs wireless communication with the wireless terminal.
- An instruction to use the allocated radio resource is transmitted to the radio apparatus, and the radio apparatus is configured to transmit the radio based on the instruction from the radio control apparatus.
- the wireless terminal performs processing for performing wireless communication using the allocated wireless resource for data to be transmitted to the terminal, converts the signal processed by the wireless signal processing means into a wireless signal, and Send to.
- the present invention it is possible to provide a wireless communication system and a wireless communication method for efficiently performing communication between a wireless control device and a wireless device.
- FIG. 1 is a diagram showing a wireless communication system according to a first exemplary embodiment. It is a figure which illustrates the protocol stack of the user plane in LTE.
- FIG. 6 is a diagram illustrating a state where the function sharing of the protocol processing is performed between the center node and the access point according to the first embodiment.
- FIG. 3 is a block diagram illustrating a configuration of software that operates in the center node according to the first embodiment; 1 is a block diagram showing a configuration of a radio signal processing unit according to a first exemplary embodiment; FIG. 3 is a diagram showing a wireless communication system according to a second exemplary embodiment.
- FIG. 10 is a diagram illustrating a specific configuration of software that operates in the center node according to the third embodiment; It is a figure which illustrates the state where the radio
- FIG. 10 is a diagram illustrating a specific configuration of a wireless signal processing unit according to the third embodiment; It is a figure for demonstrating the timing of downlink HARQ.
- FIG. 10 is a diagram illustrating a specific configuration of software that operates in the center node according to the third embodiment; It is a figure which illustrates the state where the radio
- FIG. 10 is a diagram illustrating a specific configuration of a wireless signal processing unit according to the third embodiment; It is a figure for demonstrating the timing of downlink HAR
- FIG. 10 is a diagram illustrating a specific configuration of a wireless signal processing unit according to a fourth embodiment;
- FIG. 10 is a diagram illustrating a state in which function sharing of protocol processing is performed between a center node and an access point according to the fifth embodiment.
- FIG. 10 is a diagram illustrating a state in which function sharing of protocol processing is performed between a center node and an access point according to the sixth embodiment.
- FIG. 20 is a diagram illustrating a state in which function sharing of protocol processing is performed by the center node, the relay node, and the second access point according to the seventh embodiment.
- FIG. 20 is a diagram illustrating a state in which function sharing of protocol processing is performed between a center node and an access point according to the eighth embodiment.
- FIG. 20 is a diagram illustrating a state in which function sharing of protocol processing is performed between a center node and an access point according to the ninth embodiment.
- FIG. 1 is a diagram showing an outline of a wireless communication system 1 according to an embodiment of the present invention.
- the wireless communication system 1 includes a wireless control device 20 and at least one wireless device 30.
- the wireless device 30 is connected to the wireless control device 20 via the transmission path 10 and performs wireless communication with at least one wireless terminal 2.
- the radio control apparatus 20 includes a radio resource allocation unit 22 (radio resource allocation unit) and a radio resource instruction unit 24 (radio resource instruction unit).
- the radio resource allocation unit 22 allocates radio resources used when the radio device 30 performs radio communication with the radio terminal 2.
- the radio resource instruction unit 24 transmits an instruction to use the allocated radio resource to the radio device 30.
- the wireless device 30 includes a wireless signal processing unit 32 (wireless signal processing means) and a wireless transmission unit 34 (wireless transmission means). Based on an instruction from the radio network controller 20, the radio signal processor 32 performs processing for performing radio communication on the data to be transmitted to the radio terminal 2 using the allocated radio resource.
- the wireless transmission unit 34 converts the signal processed by the wireless signal processing unit 32 into a wireless signal and transmits the wireless signal to the wireless terminal 2.
- the wireless communication system 1 and the method thereof it is possible to reduce the amount of data (data rate) transmitted through the transmission line 10 between the wireless control device 20 and the wireless device 30. It becomes. Therefore, communication between the wireless control device 20 and the wireless device 30 can be performed efficiently.
- the wireless control device 20 or the wireless device 30 can also efficiently perform communication between the wireless control device 20 and the wireless device 30.
- the wireless control device 20 and the wireless device can also be configured by providing a relay device between the wireless control device 20 and the wireless device 30 and configuring the relay device to have the wireless signal processing unit 32 instead of the wireless device 30. Communication with 30 (relay device) can be performed efficiently.
- FIG. 2 is a diagram of the wireless communication system 100 according to the first embodiment.
- the radio communication system 100 may be, for example, a radio access network (RAN: Radio Access Network).
- the wireless communication system 100 includes a center node 200, and a plurality of access points 300-1 (access point # 1) and access point 300-2 (access point # 2).
- a plurality of wireless terminals 120-1 (wireless terminal # 1) and 120-2 (wireless terminal # 2) perform wireless communication with the wireless communication system 100.
- the center node 200 corresponds to a radio control device.
- the access point 300 corresponds to a wireless device.
- the number of access points 300 is two, but is not limited thereto.
- the number of access points 300 may be one, or may be three or more.
- the number of wireless terminals 120 is two, but is not limited thereto.
- the number of wireless terminals 120 may be one, or may be three or more. The same applies to the other embodiments.
- the center node 200 is connected to the core network 104 via the backhaul 102.
- the center node 200 and the access point 300 are provided at physically separated positions and are connected to each other via the transmission path 110.
- the wireless terminal 120 is a mobile communication terminal such as a mobile phone or a smartphone.
- the wireless terminal 120 transmits and receives wireless signals to and from the access point 300.
- the transmission path 110 is a medium for transmitting information, such as an optical fiber, a metal cable, or radio.
- the transmission path 110 may conform to, for example, Ethernet (registered trademark), but is not limited thereto.
- Ethernet registered trademark
- user data and control channels / control signals transmitted / received between the center node 200 and the access point 300 other than the user data are transmitted.
- the center node 200 and the access point 300 are connected via a transmission line 110 constituted by one or a plurality of media.
- the transmission line 110 may be composed of only an optical fiber.
- the transmission line 110 may be composed of an optical fiber and a wireless or metal cable.
- the transmission path 110 is formed by wiring from the center node 200 to the vicinity of the access point 300 using an optical fiber and wiring the remaining several tens of meters using a wireless or metal cable in order to simplify the wiring work. May be.
- the transmission path 110 that connects the center node 200 and the access point 300-1 and the transmission path 110 that connects the center node 200 and the access point 300-2 are configured separately. However, it is not limited to such a configuration. When the access point 300-1 and the access point 300-2 are adjacent to each other, a part of the transmission path 110 may be shared. In this case, a distributor may be provided in the vicinity of the access point 300.
- the distributor performs, for example, multiplexing / demultiplexing of wavelength-multiplexed signals and multiplexing / separation of time-multiplexed signals.
- the center node 200 includes a reference clock generation unit 202, a general-purpose server 204, and a transmission path interface 206 (transmission path IF (Interface)).
- the reference clock generation unit 202 generates a reference clock for performing synchronization processing in the wireless communication system 100.
- the reference clock will be described later.
- the general-purpose server 204 is composed of one or a plurality of computers.
- the general-purpose server 204 executes software 210. Specifically, the general-purpose server 204 loads software 210 stored in a recording medium (not shown) into a memory (not shown), and executes a calculation device (not shown) such as a CPU (Central Processing Unit).
- the software 210 is executed under control. That is, the software 210 operates on the general-purpose server 204.
- the software 210 will be described later.
- the transmission path interface 206 performs processing according to the standard (for example, Ethernet) of the transmission path 110 when transmitting / receiving data to / from the access point 300 via the transmission path 110.
- the access point 300 includes a transmission path interface 302 (transmission path IF (Interface)), a wireless signal processing unit 310, a wireless transmission / reception unit 304, and an antenna 306.
- the antenna 306 is composed of a plurality of antennas, and may be an antenna array composed of a plurality of antenna elements, for example.
- the transmission path interface 302 performs processing according to the standard (for example, Ethernet) of the transmission path 110 when transmitting / receiving data to / from the center node 200 via the transmission path 110.
- the wireless signal processing unit 310 and the wireless transmission / reception unit 304 will be described later.
- the wireless terminal 120 communicates with a wireless access network (wireless communication system 100) via one or more access points 300.
- a downlink signal (a signal from the access point 300 to the wireless terminal 120) is transmitted from the plurality of access points 300 to one wireless terminal 120
- the plurality of access points 300 may use different frequencies. However, the same frequency may be used.
- each of the plurality of access points 300 may transmit different data to the single wireless terminal 120 or may transmit the same data.
- whether the frequencies are the same and whether the data are the same do not correspond to each other. That is, the same data may be transmitted using different frequencies, or the same data may be transmitted using the same frequency.
- the access point 300 transmits downlink signals to the plurality of wireless terminals 120 using different frequencies.
- downlink signals may be transmitted to a plurality of wireless terminals 120 using the same frequency.
- a space such as MU-MIMO (multi-user multiple-input multiple-output) or beamforming (beam-forming) is used. Multiple techniques may be applied.
- the center node 200 and the access point 300 share the functions of the radio base stations for processing.
- the downlink direction from the center node 200 to the access point 300, the access point 300 to the wireless terminal 120
- the uplink direction from the wireless terminal 120 to the access point 300, access It is clear that the corresponding operation is also performed from the point 300 to the center node 200).
- FIG. 3 is a diagram exemplifying a user-plane protocol stack (user-plane protocol stack) in LTE. This figure is shown in Non-Patent Document 4. As illustrated in FIG. 3, the protocol stack of the user plane is divided into a layer 2 protocol (L2) and a layer 1 (PHY: physical layer) protocol (L1). Layer 2 includes three sublayers of PDCP (Packet Data Convergence Protocol), RLC (Radio Link Control) and MAC (Media Access Control). Layer 2 and layer 1 are connected by a transport channel (transport channel), and user data MAC_PDU (Protocol Data Unit) is transmitted.
- PDCP Packet Data Convergence Protocol
- RLC Radio Link Control
- MAC Media Access Control
- the layer 2 protocol processing is a function that can be efficiently realized by software (general-purpose server). Therefore, in the present embodiment, this layer 2 protocol processing is realized by software 210 operating on the general-purpose server 204 of the center node 200. That is, the general-purpose server 204 (software 210) of the center node 200 mainly performs layer 2 processing among protocol processing of user data addressed to each wireless terminal 120.
- this layer 1 protocol processing is realized by radio signal processing section 310 of access point 300. That is, the radio signal processing unit 310 of the access point 300 mainly performs layer 1 processing among user data protocol processing addressed to each wireless terminal 120.
- FIG. 4 is a diagram illustrating a state where the function sharing of the protocol processing is performed between the center node 200 and the access point 300 according to the first embodiment.
- the L2 processing function is realized by the software 210 that is arranged in the center node 200 and operates on the general-purpose server 204.
- the L1 processing function is provided in the access point 300 and realized by the wireless signal processing unit 310.
- MAC_PDU TransportTransBlock
- FIG. 5 is a block diagram illustrating a configuration of the software 210 operating on the center node 200 according to the first embodiment.
- the software 210 includes a synchronization processing unit 212, a radio channel quality management unit 214, an access point selection unit 216, a radio resource management unit 218, a radio resource allocation unit 220, and an access point control unit 222.
- the component which the software 210 mentioned above has is an example, Comprising: It is not restricted to this.
- the synchronization processing unit 212 performs synchronization processing using the reference clock generated by the reference clock generation unit 202. In the radio access network, it is necessary to accurately adjust the radio frequency in each device. This is called frequency synchronization. Further, when time division duplex (TDD) is used as a wireless system, it is necessary to accurately match transmission / reception switching timings among a plurality of access points 300. This is called timing synchronization. This timing synchronization is necessary not only for the access point 300 but also for processing in the center node 200. The synchronization processing unit 212 performs processing for performing these frequency synchronization and timing synchronization. The synchronization processor 212 uses a reference clock to transmit a signal (synchronization signal) for synchronizing the access point 300 to the access point 300 via the transmission path interface 206 and the transmission path 110. I do.
- the synchronization processing unit 212 uses a protocol such as Synchronous Ethernet (registered trademark) and PTP (Precision Time Protocol) defined in IEEE 1588 to transmit a reference clock via the transmission line 110. Thus, processing for distributing to each access point 300 is performed.
- synchronous Ethernet is used for frequency synchronization.
- PTP is used for frequency synchronization and timing synchronization.
- the center node 200 uses a GNSS (Global Navigation Satellite System) such as GPS (Global Positioning System), or in combination with the above-described method, and the frequency of each node in the radio access network. And the timing may be synchronized.
- GNSS Global Navigation Satellite System
- GPS Global Positioning System
- timing synchronization between a plurality of access points 300 is not essential. However, as will be described later, when a cooperative operation is performed between a plurality of access points 300, it is preferable that the timing is synchronized between the plurality of access points 300.
- the cooperative operation between the access points is, for example, the case where one wireless terminal 120 and a plurality of access points 300 communicate simultaneously, or the same wireless communication in order to reduce interference between adjacent access points 300. This can be implemented when avoiding the use of resources.
- the radio channel quality management unit 214 manages the quality of radio channels (propagation loss, received signal strength, noise / interference magnitude, etc.) between each radio terminal 120 and each access point 300. Specifically, the radio channel quality management unit 214 transmits information (radio channel quality information) related to radio channel quality between each access point 300 and each radio terminal 120 from each access point 300 and the transmission path 110. Receive via the road interface 206. Note that each access point 300 may generate radio channel quality information by receiving information such as CQI (Channel Quality Indicator) from each radio terminal 120, for example.
- CQI Channel Quality Indicator
- the access point selection unit 216 selects, for each wireless terminal 120, an access point 300 that performs wireless communication with the wireless terminal 120. Specifically, the access point selection unit 216 uses the radio channel quality managed by the radio channel quality management unit 214 to select one or more access points 300 corresponding to the radio channel with the best quality. Then, the access point selection unit 216 transmits a control signal for causing the selected access point 300 to communicate with the wireless terminal 120 via the transmission path interface 206 and the transmission path 110. In this way, the center node 200 communicates with the wireless terminal 120 via the access point 300 with the best quality. Note that the structure of this embodiment is not necessarily limited to this method.
- the radio resource management unit 218 manages radio resources that can be used by each access point 300.
- the radio resource is, for example, a time slot, frequency, transmission power, space, and the like, but is not limited thereto.
- the radio resource allocation unit 220 is, for example, a scheduler, and performs processing (scheduling) for allocating radio resources to the radio terminal 120. Specifically, it is determined with which wireless terminal 120 the wireless resource managed by the wireless resource management unit 218 is used. Then, the radio resource assignment unit 220 transmits a radio resource instruction signal to the access point 300 via the transmission path interface 206 and the transmission path 110.
- the radio resource instruction signal is an instruction signal for instructing the access point 300 of radio resources used for transmission / reception with the communication target radio terminal 120, and causes the access point 300 to use the allocated radio resources. Instructions for
- the radio resource allocation unit 220 performs scheduling so as to increase the total throughput while maintaining fairness among the radio terminals 120. Specifically, the radio resource allocating unit 220 includes the amount of data (packets) to be transmitted to each radio terminal 120, the communication speed and delay time required according to the service type (data communication, voice communication, etc.), The transmission status of each wireless terminal 120 is determined. And the radio
- the access point control unit 222 (wireless device control means) has a function of monitoring and controlling each access point 300.
- the access point control unit 222 transmits a monitoring / control signal for monitoring and controlling the access point 300 to the access point 300 via the transmission path interface 206 and the transmission path 110.
- the access point control unit 222 controls the components of the center node 200 and performs a process for causing the plurality of access points 300 to operate cooperatively. Specifically, the following processing is performed.
- the access point control unit 222 may perform control so that different access points 300 are used for the uplink and the downlink.
- downlink data is transmitted from the access point 300-1 (access point # 1) to the wireless terminal 120
- an ACK / NACK signal indicating whether the wireless terminal 120 has correctly received the downlink data is: It may be received at access point 300-2 (access point # 2).
- the access point control unit 222 may perform control such that the access point # 1 is selected on the downlink and the access point # 2 is selected on the uplink.
- the center node 200 access point control unit 222 can determine whether to transmit new data or retransmit old data.
- the access point control unit 222 may From the point 300, the same data may be simultaneously transmitted using the same frequency. As a result, data redundancy can be achieved, so that the reception quality of the wireless terminal 120 can be improved. In this case, the access point control unit 222 may perform control so that the radio resource utilization methods at the plurality of access points 300 are matched. Further, the access point control unit 222 transmits data from the center node 200 to each access point 300 (access point # 1 and access point # 2) so that each access point 300 can transmit the same data at the same timing. You may control to deliver.
- the access point control unit 222 when a certain wireless terminal 120 is located in the vicinity of an area (cell) of a plurality of access points 300 (access point # 1 and access point # 2), the access point control unit 222 has the highest wireless channel quality. Control may be performed so that data is transmitted only from the good access point 300. In this case, the access point control unit 222 may control other access points 300 to stop using radio resources that cause interference. As a result, the reception quality of the wireless terminal 120 can be improved.
- the access point control unit 222 may From the point 300, different data may be transmitted using different frequencies at the same time.
- “different data” refers to each partial data obtained by dividing user data. Thereby, carrier aggregation between the access points 300 can be realized, and therefore, the throughput of the wireless terminal 120 can be improved.
- the access point control unit 222 may From the point 300, it may be controlled to transmit different data using the same frequency at the same time. As a result, MIMO communication between the access points 300 can be realized, and thus the throughput of the wireless terminal 120 can be improved.
- the access point control unit 222 may perform control so that the same data is transmitted simultaneously from the plurality of access points 300 using the same frequency. As a result, data redundancy can be achieved, so that data can be reliably transmitted to the wireless terminal 120.
- the software 210 performs at least one of the processes related to the layer 2 protocol (process related to PDCP, RLC, and MAC) shown in FIG. 3 other than the processes described above.
- the above-described processing such as access point selection, radio resource selection, and cooperative operation between access points 300 is complicated to be performed by hardware.
- the above-described processing is suitable for software processing using a general-purpose server 204 equipped with a general-purpose processor. Therefore, in the present embodiment, the above-described processing can be performed efficiently.
- FIG. 6 is a block diagram of a configuration of the wireless signal processing unit 310 according to the first embodiment.
- the radio signal processing unit 310 includes a channel encoding unit 312, a modulation unit 314, a physical antenna mapping unit 316, a physical antenna combining unit 322, a demodulation unit 324, and a channel decoding unit 326.
- the radio signal processing unit 310 performs transmission processing related to the layer 1 protocol on the downlink user data (MAC_PDU). Further, the radio signal processing unit 310 converts user data into a baseband signal by transmission processing. Radio signal processing section 310 transmits the baseband signal to radio transmission / reception section 304. Specifically, the channel coding unit 312 performs channel coding processing on downlink user data (MAC_PDU) received by the transmission path interface 302 via the transmission path 110. Modulation section 314 performs modulation processing on the data that has been subjected to channel coding processing. Here, the modulation unit 314 may perform modulation processing by an OFDM (Orthogonal Frequency Division Multiplexing) method.
- OFDM Orthogonal Frequency Division Multiplexing
- the physical antenna mapping unit 316 (antenna weighting means) performs transmission antenna weighting processing on each antenna of the antenna 306 composed of a plurality of antennas on the data subjected to modulation processing.
- the transmission antenna weighting process is a process of controlling the amplitude / phase for each of a plurality of antenna elements constituting the antenna 306.
- the wireless transmission / reception unit 304 converts the baseband signal subjected to the transmission antenna weighting process into a wireless signal. Further, the wireless transmission / reception unit 304 transmits a wireless signal to each wireless terminal 120 via the antenna 306.
- the wireless transmission / reception unit 304 receives an uplink signal (wireless signal) from each wireless terminal 120 via the antenna 306. Then, the wireless transmission / reception unit 304 converts the uplink signal into a digital baseband signal.
- the radio signal processing unit 310 performs reception processing related to the layer 1 protocol on the uplink signal (baseband signal). Further, the wireless signal processing unit 310 converts the baseband signal into user data (MAC_PDU) by reception processing, and transmits the user data (MAC_PDU) to the transmission path interface 302.
- the physical antenna combining unit 322 performs a reception antenna weighting process on each antenna of the antenna 306 including a plurality of antennas with respect to the baseband signal.
- the receiving antenna weighting process is a process of adding received signals of all antennas after multiplying different amplitudes / phases for a plurality of antenna elements constituting the antenna 306.
- the demodulator 324 performs demodulation processing on the signal that has been subjected to reception antenna weighting processing.
- the demodulation unit 324 may perform demodulation processing using the OFDM method.
- Channel decoding section 326 performs channel decoding processing on the demodulated signal.
- the transmission antenna weighting process and the reception antenna weighting process are collectively referred to as antenna weighting process.
- radio resources used for transmission and reception to each radio terminal 120 are used in accordance with instructions from the center node 200. That is, the access point 300 receives a radio resource instruction signal from the center node 200. Then, the radio signal processing unit 310 and the radio transmission / reception unit 304 perform appropriate processing according to the received radio resource instruction signal.
- MAC_PDU Transport Block
- MAC_PDU Transport Block
- a center side device BDE, REC, master station device, etc.
- the baseband signal is transmitted on the transmission path connecting the center side device and the antenna side device.
- the data amount of the baseband signal is larger than that of the MAC_PDU.
- antenna combining processing such as antenna weighting processing (beam forming, MIMO precoding, etc.), modulation / demodulation processing, channel coding / decoding processing, which causes an increase in data rate. At least one of the above is performed not by the center node 200 but by the access point 300. Therefore, in radio communication system 100 according to the present embodiment, it is possible to reduce the data rate of transmission path 110 between center node 200 and access point 300.
- the data rate of the transmission path between the center-side radio control unit (REC, etc.) and the antenna-side radio unit (RE, etc.) is proportional to the product of the bandwidth and the number of antennas. Increase. For example, in the specification of LTE channel bandwidth 20 MHz / 2 antenna (2 ⁇ 2 MIMO), which is the current standard configuration, a data rate of about 2 Gbps is required. On the other hand, when this specification increases to 100 MHz / 128 antennas, a data rate of 640 Gbps, which is 320 times 2 Gbps, is required. This data rate far exceeds the range that can be economically realized even when optical fibers are used.
- a method for increasing the number of antenna sites may be considered.
- the data rate of the transmission path between one center-side radio control unit (such as REC) and the antenna-side radio unit (such as RE) does not change.
- the number of optical fibers connected to the center-side radio control unit (such as REC) increases in proportion to the number of antenna sites. Therefore, the total data rate per center-side radio control unit (REC, etc.) is greatly increased.
- the peak throughput of user data is about 150 Mbps.
- This data rate is significantly reduced as compared with the bit rate of about 2 Gbps required in the related technology adopting CPRI as a transmission path standard.
- the bit rate is about 640 Gbps in the related technology, and the signal can be economically transmitted with a small number of optical fibers. Transmission is not possible.
- the bit rate can be greatly reduced as described above, and therefore, for example, 10 Gbps Ethernet (10 GBASE-SR / LR) or 40 Gbps Ethernet (40 GBASE-LR 4) is adopted as the transmission path specification. It becomes possible. Therefore, data can be transmitted economically.
- the bit rate in the transmission line 110 between the center node 200 and the access point 300 can be reduced, so that the delay in the transmission line can be reduced. It becomes possible.
- LTE Long Term Evolution
- user data is scheduled in units of subframes with a period of 1 ms. Therefore, the delay of the transmission path is required to be sufficiently shorter than 1 ms. This is because the quality of the radio channel varies with time due to fading or the like. Therefore, even if the center node 200 schedules (selects) the best access point and radio resource, if the delay is large, there is a high possibility that the center node 200 is not necessarily the best selection when actually used.
- HARQ Hybrid ARQ
- the reason why a short transmission path delay is required may be as follows.
- HARQ Hybrid ARQ
- the period of transmission (downlink), ACK / NACK response (uplink), and retransmission (downlink) exceeds 8 subframes (8 ms)
- data cannot be transmitted continuously. Therefore, the peak throughput per wireless terminal 120 is reduced.
- the transmission delay of the optical fiber is about 5 ⁇ s / km
- the maximum delay is 100 ⁇ s when the optical fiber length is 20 km at the maximum. Therefore, a short transmission path delay is required.
- HARQ will be described in another embodiment described later.
- a general-purpose specification for example, Ethernet
- a general-purpose server for example, 204
- general-purpose server 204 is provided as standard. Therefore, it becomes unnecessary to add a special transmission path interface circuit. Thereby, the cost of the transmission line can be reduced.
- general-purpose parts can also be used in the access point 300.
- CPRI is adopted as the standard of the transmission path.
- This CPRI is a dedicated specification used only at the interface between the center-side radio control unit (REC, etc.) and the antenna-side radio unit (RE, etc.), and is used in many other applications. It is not compatible with standard interface specifications (eg Ethernet).
- standard interface specifications eg Ethernet
- the related technologies described above require the development of dedicated hardware and software, and there is a problem that the development cost increases and it cannot be shared with other systems, resulting in an increase in cost.
- a general-purpose server does not have a CPRI interface, it cannot be used as it is, and a dedicated CPRI interface needs to be added.
- a general-purpose specification can be used as a transmission path interface between the center node 200 (REC, etc.) and the access point 300 (RE, etc.).
- REC center node 200
- RE access point 300
- the signal processing specific to mobile radio signal processing has a very large processing amount. Further, when the radio bandwidth and the number of antennas are significantly increased, as described above, since a data amount of 640 Gbps per antenna site must be handled, a memory neck and a bus neck of the processor are generated. Furthermore, for mobile radio signal processing, even if it is implemented in hardware, such as error coding processing, bit interleaving, CRC (Cyclic Redundancy Check), etc., it is possible to use a bit calculation processing that is very simple (that can be processed efficiently) in a general-purpose processor. Calculations that are not suitable (the utilization efficiency of a 64-bit arithmetic unit is very bad) are also included. Therefore, if these processes are performed by a general-purpose processor (general-purpose server), the processing load becomes very large.
- a general-purpose processor general-purpose server
- the center node 200 (REC or the like) can be easily realized by a general-purpose processor (general-purpose server 204).
- the center node 200 (REC or the like) performs processing that can be efficiently performed by a general-purpose processor.
- the general-purpose server 204 which is poor (inefficient in processing efficiency), performs radio signal processing by an access point 300 (or a relay node described later) configured with dedicated hardware.
- the function sharing is performed between the center node 200 and the access point 300.
- the center node 200 (REC, etc.) can be easily realized by the general-purpose processor (general-purpose server 204).
- the software 210 on the general-purpose server 204 not only can the cost be reduced, but also the scalability, the software portability, and the function flexibility can be improved. It becomes possible. Details will be described later.
- the free and dense cooperative operation between the access points 300 is performed while enjoying the effects of the above-described exemplary embodiment (that is, the cooperative operation is not limited). It is possible to do so. For example, it is considered necessary in the future as well as the cooperative schemes currently considered in the 3GPP standards such as inter-site carrier aggregation, CoMP (Coordinated Multi-Point Transmission / reception), ICIC (Inter-Cell Interference Coordination), Dual Connectivity, etc. It is possible to implement freely including the cooperation system that is used. The reason is that all the management of radio resources can be performed in real time by the center node 200 (because the advantages of the conventional RRH technology can be continued as they are).
- FIG. 7 is a diagram of a wireless communication system 150 according to the second embodiment.
- the radio communication system 150 may be a radio access network, for example.
- the wireless communication system 150 includes a center node 200, one or more access points 300, one or more relay nodes 400 (relay apparatuses), a second access point 500-1 (second access point # 1), 2 access point 500-2 (second access point # 2).
- a plurality of wireless terminals 120-1 (wireless terminal # 1) and 120-2 (wireless terminal # 2) perform wireless communication with the wireless communication system 150.
- symbol is attached
- the relay node 400 is provided between the center node 200 and the second access point 500.
- the relay node 400 is provided at a position physically separated from the center node 200 and the second access point 500.
- the relay node 400 is connected to the center node 200 via the transmission path 110.
- the relay node 400 is connected to the second access point 500 via the transmission path 112.
- the number of the second access points 500 is two, but is not limited thereto.
- the number of second access points 500 may be one, or may be three or more.
- the number of relay nodes 400 is one, but is not limited thereto.
- the number of relay nodes 400 may be two or more. The same applies to the other embodiments.
- the wireless terminal 120 transmits and receives wireless signals to and from the access point 300 and the second access point 500.
- the frequency usage at the access point 300 and the second access point 500, the data transmission method, the frequency usage between the plurality of wireless terminals 120, and the like are the same as in the first embodiment.
- the relay node 400 includes a transmission path interface 402, a radio signal processing unit 410, and a transmission path interface 404.
- the second access point 500 includes a transmission path interface 502, a wireless transmission / reception unit 504, and an antenna 506. That is, in the second embodiment, the second access point 500 does not have a radio signal processing unit. Instead, the relay node 400 includes a wireless signal processing unit 410.
- the function of the second access point 500 may be the same as the function of the RRH-equipped radio device (RRE) or the radio unit (RE) described in the non-patent document described above.
- the bandwidth, the number of antennas, and the like applied to the second access point 500 are not necessarily the same as those of the RRH-equipped radio apparatus (RRE) or the radio unit (RE).
- the second access point 500 may realize part of the function of the radio signal processing unit 410 provided in the relay node 400.
- the transmission path interface 402 of the relay node 400 has the same function as the transmission path interface 302 according to the first embodiment.
- the wireless signal processing unit 410 has the same function as the wireless signal processing unit 310 according to the first embodiment.
- the relay node 400 executes the function of the radio signal processing unit 310 provided in the access point 300 instead of the second access point 500.
- the transmission path interface 404 performs processing according to the standard of the transmission path 112 when transmitting and receiving signals (data) to and from the second access point 500 via the transmission path 112.
- radio resources used for transmission and reception to each radio terminal 120 are used in accordance with instructions from the center node 200. That is, center node 200 transmits a radio resource instruction signal to relay node 400. Then, the relay node 400 receives the radio resource instruction signal from the center node 200. Also, the radio signal processing unit 410 performs appropriate processing so that the second access point 500 can transmit and receive signals in accordance with the received radio resource instruction signal.
- the transmission path 112 is a medium for transmitting information, such as an optical fiber, a metal cable, or radio.
- the function of the second access point 500 is the same function as the RRH-equipped radio apparatus (RRE) or the radio unit (RE) described in the non-patent literature. Therefore, in order to connect the second access point 500 and the relay node 400, the transmission path 112 may conform to, for example, CPRI. However, the transmission path 112 may not conform to the CPRI. For example, when the second access point 500 realizes a part of the function of the radio signal processing unit 410 of the relay node 400 (such as shown in FIG. 18 described later), the transmission path 112 may conform to Ethernet.
- the transmission path interface 502 of the second access point 500 performs processing according to the standard of the transmission path 112 when transmitting and receiving signals (data) to and from the relay node 400 via the transmission path 112.
- the wireless transmission / reception unit 504 has the same function as the wireless transmission / reception unit 304 according to the first embodiment. That is, the wireless transmission / reception unit 504 converts a digital signal (baseband signal) into a wireless signal (RF), and converts the wireless signal into a digital signal (baseband signal).
- the antenna 506 includes a plurality of antennas.
- the antenna 506 may be an antenna array including a plurality of antenna elements.
- the operation of the center node 200 is the same as that of the center node 200 according to the first embodiment.
- the center node 200 performs the above-described processing without distinguishing between the directly connected access point 300 and the second access point 500 connected via the relay node 400. That is, the center node 200 also distinguishes between cooperative operations between access points having different functions, such as the access point 300 having the wireless signal processing unit 310 and the second access point 500 having no wireless signal processing unit. It becomes possible to execute without.
- the wireless terminal 120 communicates with the wireless access network (wireless communication system 150) via one or more access points (access point 300, second access points 500-1 and 500-2).
- the operation of the wireless terminal 120 is the same as that of the wireless terminal 120 according to the first embodiment.
- the wireless terminal 120 performs communication without distinction between the access point 300 directly connected to the center node 200 and the second access point 500 connected to the center node 200 via the relay node 400. . That is, the wireless terminal 120 communicates without distinction from access points having different functions, such as the access point 300 having the wireless signal processing unit 310 and the second access point 500 having no wireless signal processing unit. It becomes possible to do.
- the relay node 400 As described above, in the second embodiment, all or part of the function of the radio signal processing unit 310 provided in the access point 300 is provided separately in the relay node 400. As a result, it is possible to increase the degree of freedom such as the installation location of the apparatus, the transmission path data rate, and the sharing of processing resources. Further, the relay node 400 may be installed in the vicinity of the center node 200 or in the vicinity of the second access point 500 depending on the purpose of use or the like.
- Advantages of installing the relay node 400 in the vicinity of the center node 200 include the following. That is, when the function of the center node is changed from the function of the radio base station apparatus digital processing unit (BDE) or the radio control unit (REC) in the related technology described above to the function of the center node 200 according to the present embodiment. Even if it exists, it becomes possible to continue using the light projection radio
- the advantages of installing the relay node 400 in the vicinity of the plurality of second access points 500-1 and 500-2 include the following. That is, the transmission path (transmission path 110) between the center node 200 and the second access point 500 can be shared by the plurality of second access points 500-1 and the second access point 500-2. . As a result, it is not necessary to separately lay transmission lines, and costs can be reduced. Note that a baseband signal (IQ sample) having a large amount of data is transmitted on the transmission path 112 between the relay node 400 and the second access point 500. Therefore, the transmission path 112 is required to have a high bit rate. However, when the relay node 400 is installed in the vicinity of the second access point 500 (for example, both devices are installed on the same floor of one building or an underground street passage), the cost of the transmission path 112 is There is little impact.
- FIG. 8 is a diagram illustrating a state where the function sharing of the protocol processing is performed by the center node 200, the relay node 400, and the second access point 500.
- the L2 processing function is realized by software 210 that is arranged in the center node 200 and operates on the general-purpose server 204.
- the L1 processing function is provided in the relay node 400 and realized by the wireless signal processing unit 410.
- MAC_PDU Transport Block
- IQ samples digital baseband signals
- the transmission path 110 between the center node 200 and the relay node 400 conforms to, for example, Ethernet.
- the transmission path 112 between the relay node 400 and the second access point 500 is based on, for example, CPRI.
- an RRH-equipped radio device (RRE) or a radio unit (RE) described in non-patent literature can be used as the second access point 500.
- FIG. 9 is a diagram illustrating a specific configuration of the software 210 operating on the center node 200 according to the third embodiment.
- the configuration shown in FIG. 9 is the configuration of the layer 2 protocol (downlink) shown in Non-Patent Document 4.
- This layer 2 protocol does not include radio-specific signal processing (layer 1 protocol processing or the like). Therefore, the processing of the layer 2 protocol shown in Non-Patent Document 4 can be realized by the software 210 that operates on the general-purpose server 204 of the center node 200.
- the software 210 allocates a radio resource to each user (wireless terminal 120) as illustrated in FIG. 10 described later by the process illustrated in FIG.
- the software 210 includes a PDCP processing unit 240, an RLC processing unit 250, and a MAC processing unit 260.
- the PDCP processing unit 240 performs processing related to the PDCP sublayer.
- the PDCP sublayer includes a “ROHC (Robust Header Compression)” function and a “Security” function. That is, the PDCP processing unit 240 executes the “ROHC” function and the “Security” function.
- the RLC processing unit 250 performs processing related to the RLC sublayer.
- the RLC sublayer includes a “Segmentation” function, an “ARQ (Automatic Repeat Request)” function, and the like.
- the RLC processing unit 250 executes a “Segmentation” function, an “ARQ (Automatic Repeat Request)” function, and the like.
- the MAC processing unit 260 performs processing related to the MAC sublayer.
- the MAC sublayer has a scheduling function (“Unicast Scheduling / Priority Handling” function and “MBMS Scheduling (MBMS: Multimedia and Multicast Service)” function), and a plurality of logical channels addressed to one wireless terminal 120 (UE). It includes a demultiplexing function (“Multiplexing” function) executed when used, a “HARQ (HybridbrAutomatic Repeat Request)” function, and the like. That is, the MAC processing unit 260 performs a scheduling function, a demultiplexing function, a “HARQ” function, and the like.
- the MAC scheduling function is a function for determining which radio resource is used for which radio terminal, and takes into account priority and fairness among users so as to increase the use efficiency of radio resources. This is a function for making a determination in a subframe (1 ms) cycle.
- the MAC scheduling function is realized by the general-purpose server 204 (software 210) of the center node 200. That is, the center node 200 collectively assigns radio resources for a plurality of access points (access point 300 or second access point 500). In order to allow distributed processing by multiple processors, it is configured to divide each layer into multiple hierarchies, such as adjustment for each cell, each access point, and adjustment between multiple access points, and perform distributed scheduling for each. May be.
- the processing related to the layer 2 protocol is realized by the software 210 operating on the general-purpose server 204.
- processing related to the layer 2 protocol is configured by a general-purpose server group including a plurality of servers.
- the general-purpose server 204 can be realized.
- the number of access points 300 connected to one center node 200 is not fixed, and the number of access points 300 may increase as traffic increases. Therefore, it is desirable that the general-purpose server 204 can be scaled up as the number of access points 300 increases.
- the number of servers and the processing capacity constituting the general-purpose server 204 of the center node 200 can be easily changed. That is, the center node 200 according to the present embodiment has scalability. In this embodiment, it is possible to easily replace not only the number of servers constituting the general-purpose server 204 but also a server having a large processing capability. That is, the center node 200 according to the present embodiment has portability.
- the individual servers constituting the general-purpose server 204 are coupled to each other by an internal network of the center node 200 such as Ethernet, and the processing capacity is exhibited by the entire server.
- the software 210 operating on the center node 200 may be assigned in advance to each physical server or CPU, or the assignment may be dynamically changed according to traffic. Further, the software 210 can be operated on a more flexible processing resource by operating on the virtual machine virtualized by the hypervisor.
- FIG. 10 is a diagram illustrating a state in which radio resources are allocated to a plurality of users.
- FIG. 10 shows an example in which radio resources (time slots, frequencies, spaces) related to each access point 300 are allocated to a plurality of users (wireless terminals 120).
- radio resources are allocated to each user (wireless terminal 120).
- the radio resource is configured in three dimensions: a time slot (subframe), a frequency (subcarrier), and a space (layer).
- FIG. 11 is a diagram illustrating a frame format.
- the frame format illustrated in FIG. 11 is adopted in LTE.
- One radio frame length is 10 ms (milliseconds).
- One radio frame is composed of 10 subframes each having a length of 1 ms.
- the subframe is composed of two slots (time slots) each having a length of 0.5 ms. That is, one radio frame is composed of 20 slots (# 0 to # 19).
- One slot is composed of seven OFDM symbols (# 0 to # 6).
- One OFDM symbol is configured by adding a cyclic prefix (CP) to effective data.
- This “slot” is the minimum unit of radio resources to be allocated (corresponding to resource elements described later).
- FIG. 12 is a diagram illustrating a plurality of subcarriers.
- LTE as illustrated in FIG. 12, an OFDM scheme of a plurality of subcarriers is used.
- this bandwidth includes 1200 subcarriers (since the center subcarrier is not used).
- “space” can also be used as one of radio resources by techniques such as beam forming and MIMO. is there.
- “space”, which is one of the radio resources, is allocated to one user (radio terminal 120) by the SU-MIMO (Single-User-MIMO) technique as long as it is within the number of receiving antennas of the radio terminal 120. It can also be assigned to multiple users (wireless terminals 120).
- user 1 in the first subframe (1 ms length), user 1 (wireless terminal 120-1) is assigned two layers (layer 1 and layer 2).
- user 2 in the first subframe, user 2 (wireless terminal 120-2) is assigned two layers (layer 1 and layer 2).
- user 3 in the first subframe, user 3 (wireless terminal 120-3) is assigned one layer (layer 3).
- user 4 wireless terminal 120-4) is assigned one layer (layer 4).
- user 5 in the first subframe, user 5 (wireless terminal 120-5) is assigned two layers (layer 3 and layer 4).
- layer 1 (and layer 2) is assigned to both user 1 and user 2, but by assigning different frequencies (different subcarriers) to user 1 and user 2, user 1 and user 2 are assigned.
- the radio resources allocated in the above are separated.
- the layer 3 is assigned to both the user 3 and the user 5, but by assigning different frequencies (different subcarriers) to the user 3 and the user 5, the radio assigned to the user 3 and the user 5 is assigned. Resources are isolated. The same applies to layer 4. Thereby, the multiplicity of the space is 4.
- each access point 300 has a number of “space” (layer) degrees of freedom equal to the number of antennas (the number of antenna elements constituting the antenna 306), and spatial multiplexing below this degree of freedom is possible.
- the number of spatial multiplexing that can actually be used depends on the size of the cross-correlation of the channel with the receiving antenna of each wireless terminal 120, the reception level at each wireless terminal 120, the size of the noise / interference level, etc. Change.
- FIG. 13 is a diagram illustrating a specific configuration of the wireless signal processing unit 310 according to the third embodiment.
- the wireless signal processing unit 410 (Embodiment 2) may have the same configuration. 13 shows downlink transmission processing among the processing related to the layer 1 protocol (physical layer), the radio signal processing unit 310 also performs uplink reception processing according to a corresponding configuration. Can be executed.
- the radio signal processing unit 310 includes user processing units 342-1 to 342-N (N is an integer of 1 or more), a control channel / signal processing unit 344, a resource element mapping unit 352, OFDM symbol generation section 354 and physical antenna mapping section 356.
- User processing units 342-1 to 342-N perform processing related to each of a plurality of users (wireless terminals 120). That is, the user processing units 342-1 to 342-N perform processing related to the users 1 to N (wireless terminals 120-1 to 120-N), respectively.
- the control channel / signal processing unit 344 performs processing related to the control channel and the control signal common to each cell.
- the resource element mapping unit 352 and the OFDM symbol generation unit 354 perform processing for collecting the processing results for each of a plurality of users and the processing results of the control channels / signals into signals to be transmitted using each logical antenna port. Further, the physical antenna mapping unit 356 converts the signal for each logical antenna port into a signal to be transmitted via an actual physical antenna (antenna 306), and performs processing for mapping to each physical antenna. Details will be described below.
- the user processing unit 342 and the control channel / signal processing unit 344 include a channel encoding unit 362, a modulation mapping unit 364, a layer mapping unit 366, and a precoding unit 368.
- the channel encoding unit 362 performs channel encoding on input data (MAC_PDU; TransportTransBlock) from the layer 2 processing function (general-purpose server 204; software 210).
- the channel coding includes, for example, CRC (Cyclic Redundancy Check) addition, error correction coding, interleaving, and rate matching, but is not limited thereto.
- the modulation mapping unit 364 maps the encoded data (codewords) encoded by the channel encoding unit 362 to signal points (constellation points) corresponding to the modulation scheme. As a result, the modulation mapping unit 364 generates a modulated signal.
- the modulation scheme is, for example, BPSK (Binary Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), 16 QAM (Quadrature Amplitude Modulation), or 64 QAM, but is not limited thereto.
- the layer mapping unit 366 maps the modulation signal generated by the modulation mapping unit 364 to a plurality of layers (“space (layer)” in FIG. 10).
- the “multiple layers” are, for example, when the information rate is improved by performing spatial multiplexing such as MIMO (multi-input multi-output), or using a plurality of antennas such as transmission diversity. This is used when the error rate is reduced by transmission.
- the center node 200 (software 210) determines which layer (wireless terminal 120) is assigned to which layer. That is, the layer mapping unit 366 performs mapping processing in accordance with an instruction (such as a radio resource instruction signal) transmitted from the center node 200.
- the precoding unit 368 performs precoding on the modulated signal mapped to a plurality of layers, and outputs a signal for each logical antenna port.
- the resource element mapping unit 352 is configured with the same number as the number of logical antenna ports.
- the resource element mapping unit 352 uses the same logical antenna port and the logical antenna port output of the user processing unit 342 and the logical antenna port output of the control channel / signal processing unit 344 for a plurality of users as resource elements (Resource (Element : RE).
- resource element RE
- the resource element (RE) is one sub-carrier (frequency) and one symbol (time) as one unit.
- a resource element (RE) is a subcarrier exemplified in FIG. 12 as one unit in the frequency direction and a symbol exemplified in FIG. 11 as a unit in the time direction.
- This resource element is allocated to each user (wireless terminal 120) and control channel / signal.
- the resource element mapping unit 352 maps the logical antenna port output of the user processing unit 342 and the logical antenna port output of the control channel / signal processing unit 344 for each corresponding user (wireless terminal 120) to each of the allocated resource elements. To do. That is, the resource element mapping unit 352 performs a resource element mapping process for each logical antenna port.
- “0” is mapped for a resource element (RE) that is not allocated (not used).
- RE resource element
- the same resource element (RE) is used for a plurality of users (wireless terminals 120) and control channels / signals (that is, when spatial multiplexing is performed)
- different logical antenna ports are used.
- the same resource element (RE) is not shared by a plurality of users (wireless terminals 120) and control channels / signals. That is, each resource element mapping unit 352 illustrated in FIG. 13 does not map the same resource element to a plurality of users (wireless terminals 120) and control channels / signals.
- the output of the resource element mapping unit 352 is a subcarrier, that is, a digital baseband waveform in the frequency domain.
- the OFDM symbol generation unit 354 converts the frequency domain digital baseband waveform into a time domain digital baseband waveform using IFFT (Inverse Fourier Transform) or a circuit configuration equivalent thereto. Furthermore, the OFDM symbol generation unit 354 adds a cyclic prefix (CP) and outputs a continuous time waveform. Note that the OFDM symbol generators 354 are configured with the same number as the number of logical antenna ports.
- the physical antenna mapping unit 356 associates a logical antenna port with a physical antenna element (antenna 306). This association is closely related to antenna directivity control and spatial multiplexing. For example, the number of antenna elements constituting the antenna 306 of the access point 300 is 128, and the number of reception antennas of the wireless terminal 120 is 2. In this case, since a maximum of 2 ⁇ 2 MIMO can be spatially multiplexed for each user (wireless terminal 120), the logical antenna port for each user is 1 to 2 ports.
- the physical antenna mapping unit 356 multiplies the antenna weighting coefficient by the signal of each logical antenna port, adds the signals, and outputs the result from each physical antenna (each antenna element constituting the antenna 306).
- physical antenna mapping section 356 selects an antenna weighting coefficient so that directivity is directed toward the user (wireless terminal 120) to be transmitted. Thereby, an antenna beam for each user (wireless terminal 120) is formed.
- the physical antenna mapping unit 356 has a wide directivity that can cover the entire cell. Is selected. The same applies to an antenna port for a user (wireless terminal 120) who does not perform beamforming. In this case, the user (wireless terminal 120) can be identified by using a different resource element (RE).
- RE resource element
- the radio transmission / reception unit 304 converts the output of the physical antenna mapping unit 356 into a radio signal for each physical antenna (physical antenna port). Further, the wireless transmission / reception unit 304 performs amplification and filtering on the signal as necessary. The wireless transmission / reception unit 304 transmits a wireless signal from each antenna element constituting the antenna 306.
- the uplink reception process is symmetric with the transmission process, detailed description is omitted. Note that the received signal is affected by fluctuations in the radio propagation path such as noise, interference, and fading, and thus may be received in error. Therefore, in order to reduce the reception error rate of uplink data, a plurality of access points 300 receive the same data, and the center node 200 (software 210) selects received data received by the plurality of access points 300. ⁇ Perform the composition process. When the output of the channel decoding unit 326 of each access point 300 is a hard decision output, the selection / combination processing in the center node 200 is processing for selecting correct data by the CRC.
- the selection / combination process in the center node 200 is a process of combining the decoding results in the plurality of access points 300 and making a final determination. It becomes. Thereby, even when the CRC at all the access points 300 is incorrect, correct received data can be obtained.
- FIG. 14 is a diagram for explaining the timing of downlink HARQ.
- an 8th-order stop and wait HARQ scheme is adopted. Therefore, if retransmission or new data transmission is determined at intervals of 8 subframes, it is possible to continuously perform downlink transmission for the same wireless terminal 120, and achieve the peak rate required for the wireless terminal 120. It becomes.
- the radio terminal 120 must return an ACK / NACK response to the base station side (center node 200 and access point 300) after 4 subframes of downlink reception.
- the base station side (center node 200 and access point 300) can transmit retransmission data after 4 subframes of NACK reception.
- the timing is not determined so as to retransmit just after 4 subframes. Therefore, the base station side may freely schedule it after 4 subframes.
- the base station side may allocate radio resources to the other radio terminals 120 in order to maintain fairness with the other radio terminals 120, or if the processing time on the base station side is not in time, 4 You may schedule after a sub-frame.
- access point 300 performs uplink data demodulation processing and channel decoding processing including ACK / NACK.
- the center node 200 performs scheduling processing of a final radio resource utilization method including determination of retransmission or transmission of new data.
- the access point 300 performs encoding processing and modulation processing according to the finally determined transmission data (retransmission / new data) and the radio resource utilization method, and converts the data into a radio signal and transmits it.
- the encoding process is performed on the data of the subframe length, and before the modulation process for the OFDM symbol including the corresponding data is started. Must be terminated.
- the modulation process is performed on the data of the OFDM symbol length, and must be completed before the physical antenna mapping process of the IQ sample including the corresponding data is started.
- the physical antenna mapping process is a process for each IQ sample, and must be completed before the corresponding IQ sample is output to the wireless transmission / reception unit 304.
- it is required to reduce the delay.
- the delay can be reduced. It is possible to carry out at a proper timing.
- FIG. 15 is a diagram illustrating a specific configuration of the wireless signal processing unit 310 according to the fourth embodiment. Note that the wireless signal processing unit 410 (Embodiment 2) may have the same configuration. Also, FIG. 15 shows the downlink transmission process among the processes related to the layer 1 protocol (physical layer), as in FIG. 13, but the radio signal processing unit 310 performs the uplink reception process. Can also be implemented with a corresponding configuration.
- radio signal processing section 310 includes user processing sections 342-1 to 342-N, control channel / signal processing section 344, resource element mapping section 372, and OFDM symbol generation section 374.
- the user processing unit 342 and the control channel / signal processing unit 344 include a channel encoding unit 362, a modulation mapping unit 364, a layer mapping unit 366, a precoding unit 368, a physical antenna mapping unit 376, and a beam forming unit 378. And have.
- the physical antenna mapping unit 376 maps the signal precoded by the precoding unit 368 to a physical antenna (antenna element constituting the antenna 306) by the same processing as the physical antenna mapping unit 356.
- the beam forming unit 378 performs processing related to beam forming on the signal mapped to the physical antenna.
- the precoding unit 368, the physical antenna mapping unit 376, and the beam forming unit 378 are configured integrally, such as configured by a common circuit. In other words, the precoding process, the mapping process to the physical antenna, and the beam forming process are performed collectively.
- the difference between the fourth embodiment and the third embodiment is that precoding and beamforming are performed collectively for each physical antenna port without passing through a logical antenna port. It is.
- both precoding and beamforming are processes for multiplying the weighting coefficient for each antenna. Therefore, precoding and beamforming can be realized with a common circuit. That is, since the output signal of the layer mapping unit 366 is a frequency domain signal, it can be considered that the beamforming coefficient is multiplied in the frequency domain.
- the resource element mapping unit 372 is configured with the same number as the number of physical antenna ports.
- the resource element mapping unit 372 performs the same processing as the resource element mapping unit 352, uses the same physical antenna port, the physical antenna port output of the user processing unit 342 for a plurality of users, and the control channel / signal processing unit
- the physical antenna port output of 344 is mapped to the resource element (RE).
- the output of the resource element mapping unit 372 is a subcarrier, that is, a digital baseband waveform in the frequency domain.
- the OFDM symbol generation unit 374 converts the digital baseband waveform in the frequency domain into a digital baseband waveform in the time domain by IFFT (or an equivalent circuit). Further, the OFDM symbol generation unit 374 adds a cyclic prefix (CP) and outputs a continuous time waveform.
- generation part 374 is comprised by the same number as the number of physical antenna ports.
- the number of resource element mapping units 352 and OFDM symbol generation units 354 according to the third embodiment is the same as the number of logical antenna ports.
- the number of resource element mapping units 372 and OFDM symbol generation units 374 according to the fourth embodiment is the same as the number of physical antenna ports. Therefore, when the number of logical antenna ports is larger than the number of physical antenna ports, the required number of resource element mapping units and OFDM symbol generation units can be reduced in the fourth embodiment compared to the third embodiment. It becomes.
- spatial multiplexing is performed for a plurality of users (wireless terminals 120) by beam forming or MU-MIMO, each user is mapped to a different (logical) antenna port, and this condition is often satisfied.
- FIG. 16 is a diagram illustrating a state where the function sharing of the protocol processing is performed between the center node 200 and the access point 300 according to the fifth embodiment.
- HARQ buffer 380 is arranged at access point 300.
- the HARQ buffer 380 stores transmission data (Transport Block) transmitted from the center node 200.
- the center node 200 when retransmission is required in HARQ, the center node 200 only needs to transmit a pointer indicating which data (Transport Block) is to be retransmitted.
- the access point 300 can retransmit the data indicated by the pointer among the transmission data stored in the HARQ buffer 380. Therefore, when retransmission is required by HARQ, it becomes unnecessary to transmit retransmission data again from the center node 200 to the access point 300.
- FIG. 17 is a diagram illustrating a state where the function sharing of the protocol processing is performed between the center node 200 and the access point 300 according to the sixth embodiment.
- the center node 200 in addition to the L2 processing function, has a channel coding processing function / channel decoding processing function of the L1 processing function and a symbol division function. Has been placed. Further, the access point 300 is provided with a modulation / demodulation processing function among the L1 processing functions.
- the center node 200 performs channel coding on transmission data (downlink data) for all channels (all users) for one subframe by the channel coding processing function. Thereafter, the center node 200 divides all encoded data (Codeword) for each symbol which is a unit of modulation processing by the symbol division function. Further, the center node 200 sequentially transmits the encoded data divided for each symbol to the access point 300 so that transmission of all data necessary until the start of the modulation processing of each symbol is completed.
- the access point 300 performs modulation processing, precoding / beamforming, and OFDM symbol generation processing on the encoded data received from the center node 200 in units of symbols.
- encoded data divided into symbol units can be transmitted in small units. Therefore, in the sixth embodiment, it is possible to reduce the time required for data transmission of one unit. In addition, this makes it possible to reduce the waiting time until the transmission at the access point 300 is completed, and thus it is possible to increase the operating rate of the circuit that executes the L1 processing function.
- the function division may be similarly performed for the processing of the uplink reception data, but the effect is different from the case of the downlink transmission described above.
- the output of demodulation processing is likelihood information including the reliability of data discrimination, and is expressed by a plurality of bits (for example, 6 bits) for 1-bit transmission data. Accordingly, the uplink transmission rate increases.
- the center node 200 can perform channel decoding processing (particularly error correction processing) by combining signals received by a plurality of access points 300 by weighted addition. Therefore, it is possible to improve reception characteristics.
- the functional arrangement of the uplink reception process may not be the same as the functional arrangement of the downlink transmission process.
- channel coding processing is arranged in the center node 200 as in Embodiment 6, and for uplink reception processing, channel decoding processing is performed as an access point as in Embodiment 1 or the like.
- Functions may be shared, such as being arranged in 300.
- FIG. 18 is a diagram illustrating a state where the function sharing of the protocol processing is performed by the center node 200, the relay node 400, and the second access point 500 according to the seventh embodiment.
- the center node 200 is provided with the L2 processing function as in the second embodiment.
- relay node 400 is provided with a channel coding processing function / channel decoding processing function and a symbol division function among the L1 processing functions.
- the second access point 500 is provided with a modulation / demodulation processing function among the L1 processing functions.
- the MAC_PDU is transmitted between the center node 200 and the relay node 400 as in the second embodiment. Also, between the relay node 400 and the second access point 500, similarly to the center node 200 and the access point 300 in the sixth embodiment, channel coded data (downlink transmission data) divided into symbol units. ) Is transmitted. Similarly to the access point 300 of the sixth embodiment, the second access point 500 performs modulation processing, precoding / beamforming, OFDM symbols on the encoded data received from the relay node 400 in units of symbols. Perform the generation process.
- the center node 200 does not include a radio signal processing function, so that the processing in the general-purpose server 204 is not complicated, and therefore easy with a general-purpose processor or the like. Is feasible. Furthermore, the unit of data transmission between the relay node 400 and the second access point 500 is reduced (because it is a symbol unit), and the waiting time for data transmission can be shortened.
- FIG. 19 is a diagram illustrating a state where the function sharing of the protocol processing is performed between the center node 200 and the access point 300 according to the eighth embodiment.
- the center node 200 is provided with a PDCP processing function of the L2 processing function and a MAC scheduling function.
- the access point 300 is provided with an RLC processing function, an MAC packet disassembly / assembly function, and an L1 processing function among the L2 processing functions.
- the data buffer 382 is arranged at the access point 300.
- the center node 200 When the center node 200 performs PDCP processing by the PDCP processing function, the center node 200 transmits PDCP_PDU (transmission data body) to the access point 300 before scheduling (at least before the scheduling ends).
- the access point 300 stores the PDCP_PDU transmitted from the center node 200 in the data buffer 382.
- the center node 200 performs a scheduling process in parallel with transmitting the PDCP_PDU. Then, the center node 200 transmits a scheduling result instruction signal to the access point 300.
- the scheduling result instruction signal indicates which user (wireless terminal 120) transmits which data (whether a specific subframe is transmitted to which user, retransmission or new data, and the data size at that time is several. And so on).
- the scheduling result signal includes a pointer and a data size.
- the pointer indicates the start position of data corresponding to the subframe to be transmitted to the transmission target user (wireless terminal 120) in the transmission data body (PDCP_PDU) stored in the data buffer 382. That is, the scheduling result instruction signal indicates data for identifying a user (wireless terminal 120) to be transmitted in the subframe, a start position (pointer) of the data to be transmitted, and the size of the data.
- center node 200 transmits a radio resource instruction signal to access point 300 as in the first embodiment.
- the access point 300 assembles RLC_PDU and MAC_PDU according to the scheduling result instruction signal for the corresponding subframe, using data (transmission data body; PDCP_PDU) received in advance and stored in the data buffer 382. Further, the access point 300 performs channel coding processing, modulation processing, and precoding / beamforming processing in accordance with the radio resource indication signal. Furthermore, the access point 300 converts the generated baseband signal into a radio signal, and transmits the radio signal to the transmission target radio terminal 120 via the antenna 306.
- the center node 200 starts to transmit the data to the access point 300 after the data (MAC_PDU) actually transmitted in each subframe is determined.
- the time from the start of data transmission to the completion of data transmission becomes longer.
- the access point 300 cannot start the next processing.
- the data to be transmitted is retransmission or new data, the data size at that time, etc. must be completed. Not finalized.
- the transmission data itself is stored in advance in the data buffer 382 of the access point 300. Therefore, the center node 200 does not need to transmit the transmission data body to the access point 300 when the scheduling is completed. That is, the center node 200 only needs to instruct the access point 300 on data for identifying a user who is a transmission target in the subframe and a data start position / size.
- the transmission instruction (scheduling result instruction signal) may be interrupted in the transmission data body transmitted in advance by setting the transmission priority of the transmission instruction (scheduling result instruction signal) higher than the transmission priority of the transmission data body. It is suppressed.
- the scheduling result instruction signal indicating the user identifier to be transmitted and the start position / size of the transmission data is used as a method for instructing transmission data.
- the present invention is not limited to this.
- the method is not limited to the above method as long as it can indicate data to be actually transmitted from data stored in the data buffer 382 of the access point 300 in advance.
- the function sharing of the downlink transmission process and the function sharing of the uplink reception process are described as being the same, but the function sharing of the downlink transmission process and the function sharing of the uplink reception process are different from each other. Also good. That is, what is necessary to shorten the waiting time in the uplink signal is an ACK / NACK response to downlink data and a signal indicating whether or not uplink data has been correctly received (CRC check result).
- CRC check result the data size of the signal indicating the ACK / NACK response and the CRC check result is relatively small. Therefore, the transmission completion waiting time can be sufficiently reduced by increasing the transmission priority for these data.
- the L2 reception processing function is arranged at the center node 200, and the L1 reception processing function is arranged at the access point 300.
- the function sharing may be different between the uplink reception process.
- FIG. 20 is a diagram illustrating a state where the function sharing of the protocol processing is performed between the center node 200 and the access point 300 according to the ninth embodiment.
- the center node 200 is provided with an L2 processing function and a channel encoding function / channel decoding function and modulation / demodulation function of the L1 processing functions.
- the access point 300 is provided with a physical antenna mapping function among the L1 processing functions.
- This physical antenna mapping function is a function for mapping a logical antenna port to a physical antenna port.
- the physical antenna mapping function is the same function as the function of the physical antenna mapping unit 356 described with reference to FIG. 13 in the third embodiment, and performs weighted addition processing for each antenna.
- the effective amount of information corresponding to the logical antenna port is smaller than the amount of information corresponding to the physical antenna. Therefore, the amount of information on the transmission path between the center node 200 and the access point 300 can be reduced as compared with the CPRI format transmission according to the related art described above.
- the function sharing is performed between the center node 200 and the access point 300, but the present invention is not limited to this.
- the function sharing may be performed on the relay node 400.
- only the L2 processing function may be arranged at the center node 200, and the channel coding function and the modulation / demodulation function among the L1 processing functions may be arranged at the relay node 400.
- the present invention has been described as a hardware configuration, but the present invention is not limited to this.
- the present invention can be realized by causing a CPU (Central Processing Unit) to execute a computer program to process each circuit of each device constituting the wireless communication system.
- a CPU Central Processing Unit
- Non-transitory computer readable media include various types of tangible storage media (tangible storage medium).
- Examples of non-transitory computer-readable media include magnetic recording media (eg flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (eg magneto-optical discs), CD-ROMs (Read Only Memory), CD-Rs, CD-R / W, semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable ROM), flash ROM, RAM (Random Access Memory)) are included.
- the program may also be supplied to the computer by various types of temporary computer-readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves.
- the temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.
- a wireless control device Having at least one wireless device connected to the wireless control device via a transmission line and performing wireless communication with a wireless terminal;
- the wireless control device Radio resource allocating means for allocating radio resources used when the radio apparatus performs radio communication with the radio terminal;
- Radio resource instruction means for transmitting an instruction to use the allocated radio resource to the radio device;
- the wireless device includes: Wireless signal processing means for performing processing for performing wireless communication on the data to be transmitted to the wireless terminal using the allocated wireless resource based on an instruction from the wireless control device;
- a radio communication system comprising: radio transmission means for converting a signal processed by the radio signal processing means into a radio signal and transmitting the radio signal to the radio terminal.
- the wireless control device A wireless device selecting means for selecting the wireless device for performing wireless communication with the wireless terminal; The wireless communication system according to claim 1, wherein the selected wireless device performs wireless communication with the wireless terminal.
- the wireless control device A wireless device control means for controlling the plurality of wireless devices to perform cooperative operation; The wireless communication system according to attachment 2, wherein the plurality of wireless devices perform a cooperative operation under the control of the wireless device control means.
- the wireless device has a plurality of antennas, The wireless communication system according to any one of attachments 1 to 3, wherein the wireless signal processing means performs antenna weighting processing for each of the plurality of antennas.
- the wireless control device Sending transmission data to the wireless device before the scheduling process ends; After the scheduling process is completed, a scheduling result indicating signal indicating a scheduling result is transmitted to the wireless device,
- the wireless device includes: Storing transmission data transmitted from the radio control device;
- the wireless signal indicating the data to be transmitted to the wireless terminal is transmitted to the wireless terminal among the stored transmission data based on the scheduling result instruction signal.
- a wireless control device At least one wireless device performing wireless communication with the wireless terminal;
- a relay device provided between the radio control device and the radio device, connected to the radio control device via a first transmission path, and connected to the radio device via a second transmission path;
- the wireless control device Radio resource allocating means for allocating radio resources used when the radio apparatus performs radio communication with the radio terminal;
- Radio resource instruction means for transmitting an instruction to use the allocated radio resource to the relay device;
- the relay device performs processing for performing wireless communication using the allocated wireless resource for data to be transmitted to the wireless terminal based on an instruction from the wireless control device,
- the wireless communication system wherein the wireless device converts a signal processed by the wireless signal processing means into a wireless signal and transmits the wireless signal to the wireless terminal.
- a wireless communication method in a wireless communication system comprising: a wireless control device; and at least one wireless device connected to the wireless control device via a transmission path and performing wireless communication with a wireless terminal,
- the wireless control device Allocating radio resources used when the radio device performs radio communication with the radio terminal, An instruction to use the allocated radio resource is transmitted to the radio device;
- the wireless device Based on an instruction from the radio control device, for data to be transmitted to the radio terminal, a process for performing radio communication using the allocated radio resource is performed,
- a wireless control device connected via a transmission path to at least one wireless device that performs wireless communication with a wireless terminal, Radio resource allocating means for allocating radio resources used when the radio apparatus performs radio communication with the radio terminal;
- a radio control apparatus comprising: radio resource instruction means for transmitting an instruction for using the allocated radio resource to the radio apparatus.
- the wireless control device according to supplementary note 12, further comprising: a wireless device selection unit that selects the wireless device that performs wireless communication with the wireless terminal among the plurality of wireless devices.
- a wireless device that performs wireless communication with a wireless terminal and is connected to a wireless control device via a transmission path, For data to be transmitted to the wireless terminal based on an instruction for using the wireless resource transmitted by the wireless control device and used when the wireless device performs wireless communication with the wireless terminal, Wireless signal processing means for performing processing for performing wireless communication using the wireless resource; Radio equipment comprising: radio transmission means for converting a signal processed by the radio signal processing means into a radio signal and transmitting the radio signal to the radio terminal.
- (Appendix 16) Have multiple antennas, The wireless device according to claim 15, wherein the wireless signal processing means performs antenna weighting processing for each of the plurality of antennas.
- (Appendix 17) Provided between the wireless control device and at least one wireless device that performs wireless communication with the wireless terminal; Connected to the wireless control device via a first transmission line, connected to the wireless device via a second transmission line, Based on an instruction to use radio resources used when the radio device performs radio communication with the radio terminal, transmitted by the radio control device, for data to be transmitted to the radio terminal, A relay device that performs processing for performing wireless communication using the wireless resource.
- Appendix 18 A wireless communication method in a wireless control device connected via a transmission path to at least one wireless device that performs wireless communication with a wireless terminal, Allocating radio resources used when the radio device performs radio communication with the radio terminal, A wireless communication method for transmitting an instruction to use the allocated wireless resource to the wireless device.
- a wireless communication method in a wireless device that performs wireless communication with a wireless terminal and is connected to a wireless control device via a transmission path, For data to be transmitted to the wireless terminal based on an instruction for using the wireless resource transmitted by the wireless control device and used when the wireless device performs wireless communication with the wireless terminal, Perform processing for performing wireless communication using the wireless resource, A radio communication method for converting the processed signal into a radio signal and transmitting the radio signal to the radio terminal.
- Appendix 20 A wireless communication method in a relay device provided between a wireless control device and at least one wireless device that performs wireless communication with a wireless terminal, Based on an instruction to use radio resources used when the radio device performs radio communication with the radio terminal, transmitted by the radio control device, for data to be transmitted to the radio terminal, A wireless communication method for performing processing for performing wireless communication using the wireless resource.
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Abstract
Description
本発明の実施形態の説明に先立って、本発明にかかる実施の形態の概要について説明する。図1は、本発明の実施の形態にかかる無線通信システム1の概要を示す図である。図1に示すように、無線通信システム1は、無線制御装置20と、少なくとも1つの無線装置30とを有する。無線装置30は、無線制御装置20と伝送路10を介して接続され、少なくとも1つの無線端末2と無線通信を行う。
以下、図面を参照して実施の形態について説明する。なお、以下に示す各実施の形態においては、無線形式としてLTEを用いた例を示しているが、これに限られない。本実施の形態は、任意の無線アクセス方式および任意の複数の無線アクセス方式の組み合わせ(例えば、CDMA(Code Division Multiple Access)/HSPA(High Speed Packet Access)/LTE/LTE-advanced等の組み合わせ)にも適用可能である。
次に、実施の形態2について説明する。
図7は、実施の形態2にかかる無線通信システム150を示す図である。無線通信システム150は、例えば、無線アクセスネットワークであってもよい。無線通信システム150は、センターノード200と、1つ以上のアクセスポイント300と、1つ以上の中継ノード400(中継装置)と、第2アクセスポイント500-1(第2アクセスポイント#1),第2アクセスポイント500-2(第2アクセスポイント#2)とを有する。また、複数の無線端末120-1(無線端末#1),120-2(無線端末#2)が、この無線通信システム150と無線通信を行う。なお、上述した実施の形態と実質的に同一の構成部分については、同一の符号が付され、説明は省略される(以下同様)。
次に、実施の形態3について説明する。実施の形態3は、無線形式としてLTEを採用した場合の、上述した実施の形態かかる各装置の構成を具体的に示している。
図9は、実施の形態3にかかるセンターノード200で動作するソフトウェア210の具体的な構成を例示する図である。ここで、図9に示した構成は、非特許文献4に示されている、レイヤ2プロトコル(下りリンク)の構成である。このレイヤ2プロトコルにおいては、無線特有の信号処理(レイヤ1プロトコルの処理等)が含まれない。したがって、非特許文献4に示されたレイヤ2プロトコルの処理は、センターノード200の汎用サーバ204で動作するソフトウェア210で実現可能である。ソフトウェア210は、図9に例示する処理により、後述する図10に例示するように、無線リソースを、各ユーザ(無線端末120)に割り当てる。
図11は、フレームフォーマットを例示する図である。図11に例示したフレームフォーマットは、LTEで採用されている。1つの無線フレーム長は10ms(ミリ秒)である。また、1つの無線フレームは、1ms長の10個のサブフレームから構成されている。さらに、サブフレームは、0.5ms長の2個のスロット(タイムスロット)から構成されている。つまり、1つの無線フレームは、20個のスロット(#0~#19)から構成されている。また、1つのスロットは、7個のOFDMシンボル(#0~#6)から構成されている。1つのOFDMシンボルは、実効データにサイクリックプレフィックス(Cyclic Prefix:CP)が付加されて構成されている。この「スロット」が、割り当てられる無線リソースの最小単位(後述するリソースエレメントに対応)となる。
図12は、複数のサブキャリアを例示する図である。LTEでは、図12に例示するように、複数のサブキャリアのOFDM方式が用いられている。図12の例では、帯域幅を18MHz、サブキャリアの間隔を15kHzとすると、この帯域幅に、(センターサブキャリアを用いないので)1200個のサブキャリアが含まれる。
図14は、下りHARQのタイミングについて説明するための図である。上述したように、LTEのFDDにおいては、8次のstop and waitのHARQ方式が採用されている。したがって、8サブフレーム間隔で再送又は新規データ送信の判断を行えば、連続して同一無線端末120向けの下り送信を行うことが可能であり、無線端末120に必要とされるピークレートを実現可能となる。ここで、図14に示すように、無線端末120は、下り受信の4サブフレーム後にACK/NACK応答を、基地局側(センターノード200及びアクセスポイント300)に返信しなければならない。一方、基地局側(センターノード200及びアクセスポイント300)は、NACK受信の4サブフレーム後に再送データを送信することが可能となる。ただし、基地局側については、ちょうど4サブフレーム後に再送するようにタイミングが決まっているわけではなく、したがって、基地局側は、4サブフレーム以降であれば自由にスケジューリングしてもよい。例えば、基地局側は、他の無線端末120との公平性維持のために他無線端末120に対して無線リソースを割り当てることもあるし、基地局側における処理時間が間に合わなかった場合は、4サブフレーム以降にスケジューリングしてもよい。
図15は、実施の形態4にかかる無線信号処理部310の具体的な構成を例示する図である。なお、無線信号処理部410(実施の形態2)についても、同様の構成を有しうる。また、図15には、図13と同様に、レイヤ1プロトコル(物理レイヤ)に関する処理のうち、下り方向の送信処理が示されているが、無線信号処理部310は、上り方向の受信処理についても、対応する構成によって実行しうる。
以下の実施の形態においては、センターノード200とアクセスポイント300とにおける、レイヤ2処理及びレイヤ1処理の機能分担に関して、上述した実施の形態とは異なる例を示している。なお、無線リソース管理機能(無線リソース管理部218及び無線リソース割当部220等)、及び、無線端末120と送受信を行うアクセスポイント300の選択機能(無線回線品質管理部214及びアクセスポイント選択部216等)は、常に、センターノード200に配置される。また、無線送受信部304(及び無線送受信部504)及びアンテナ306(及びアンテナ506)は、常に、アクセスポイント300(及び第2アクセスポイント500)に配置される。したがって、これらの構成部分については、以下の実施の形態においては、適宜、説明を省略している。また、センターノード200からアクセスポイント300(第2アクセスポイント500)に送信される無線リソース指示信号に関する説明も、適宜、省略している。
図16は、実施の形態5にかかる、センターノード200とアクセスポイント300とでプロトコル処理の機能分担がなされた状態を示す図である。図16に示すように、実施の形態5においては、HARQバッファ380が、アクセスポイント300に配置されている。HARQバッファ380は、センターノード200から伝送された送信データ(Transport Block)を格納する。このような構成により、HARQで再送が必要とされる場合に、センターノード200は、どのデータ(Transport Block)を再送するかを指示するポインタのみを伝送すればよい。アクセスポイント300は、センターノード200からポインタを受信すると、HARQバッファ380に格納された送信データのうち、そのポインタで示されたデータを再送することが可能となる。したがって、HARQで再送が必要とされる場合に、センターノード200からアクセスポイント300に対して、再送データを再度伝送することが不要となる。
図17は、実施の形態6にかかる、センターノード200とアクセスポイント300とでプロトコル処理の機能分担がなされた状態を示す図である。図17に示すように、実施の形態6においては、センターノード200には、L2処理機能に加え、L1処理機能のうちのチャネル符号化処理機能/チャネル復号化処理機能と、シンボル分割機能とが配置されている。また、アクセスポイント300には、L1処理機能のうちの変復調処理機能が配置されている。
図18は、実施の形態7にかかる、センターノード200と、中継ノード400と、第2アクセスポイント500とでプロトコル処理の機能分担がなされた状態を示す図である。図18に示すように、実施の形態7においては、センターノード200には、実施の形態2等と同様に、L2処理機能が配置されている。また、中継ノード400には、L1処理機能のうちのチャネル符号化処理機能/チャネル復号化処理機能と、シンボル分割機能とが配置されている。また、第2アクセスポイント500には、L1処理機能のうちの変復調処理機能が配置されている。
図19は、実施の形態8にかかる、センターノード200とアクセスポイント300とでプロトコル処理の機能分担がなされた状態を示す図である。図19に示すように、実施の形態8においては、センターノード200には、L2処理機能のうちのPDCP処理機能と、MACのスケジューリング機能とが配置されている。また、アクセスポイント300には、L2処理機能のうちのRLC処理機能及びMACのパケット分解組立機能と、L1処理機能とが配置されている。さらに、実施の形態8においては、データバッファ382が、アクセスポイント300に配置されている。
図20は、実施の形態9にかかる、センターノード200とアクセスポイント300とでプロトコル処理の機能分担がなされた状態を示す図である。図20に示すように、実施の形態9においては、センターノード200には、L2処理機能と、L1処理機能のうちのチャネル符号化機能/チャネル復号化機能及び変復調機能とが配置されている。また、アクセスポイント300には、L1処理機能のうちの物理アンテナマッピング機能が配置されている。この物理アンテナマッピング機能は、論理アンテナポートを物理アンテナポートにマッピングする機能である。また、物理アンテナマッピング機能は、実施の形態3において図13を用いて説明した、物理アンテナマッピング部356の機能と同様の機能であり、アンテナ毎の重み付け加算処理を行う。論理アンテナポートに対応する有効な情報量は、物理アンテナに対応する情報量に比べて小さい。したがって、上述した関連技術にかかるCPRI形式の伝送に比べて、センターノード200とアクセスポイント300との間の伝送路の情報量を削減することが可能となる。
なお、本発明は上記実施の形態に限られたものではなく、趣旨を逸脱しない範囲で適宜変更することが可能である。各実施の形態の構成は、他の実施の形態に互いに適用可能である。例えば、実施の形態2の構成は、実施の形態3においても適用可能である。
無線制御装置と、
前記無線制御装置と伝送路を介して接続され、無線端末と無線通信を行う少なくとも1つの無線装置と
を有し、
前記無線制御装置は、
前記無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを割り当てる無線リソース割当手段と、
前記割り当てられた前記無線リソースを使用させるための指示を前記無線装置に対して送信する無線リソース指示手段と
を有し、
前記無線装置は、
前記無線制御装置からの指示に基づいて、前記無線端末に送信すべきデータに対して、前記割り当てられた無線リソースを用いて無線通信を行うための処理を行う無線信号処理手段と、
前記無線信号処理手段によって処理された信号を無線信号に変換して、前記無線端末に送信する無線送信手段と
を有する
無線通信システム。
(付記2)
前記無線装置は複数設けられており、
前記無線制御装置は、
前記無線端末と無線通信を行わせる前記無線装置を選択する無線装置選択手段
をさらに有し、
前記選択された無線装置は、前記無線端末と無線通信を行う
付記1に記載の無線通信システム。
(付記3)
前記無線制御装置は、
前記複数の無線装置を協調動作させるように制御する無線装置制御手段
をさらに有し、
前記複数の無線装置は、前記無線装置制御手段の制御により、協調動作を行う
付記2に記載の無線通信システム。
(付記4)
前記無線装置は、複数のアンテナを有し、
前記無線信号処理手段は、前記複数のアンテナそれぞれについてアンテナ重み付け処理を行う
付記1から3のいずれか1項に記載の無線通信システム。
(付記5)
前記無線信号処理手段は、チャネル符号化処理及びチャネル復号化処理と、変調処理及び復調処理とを行う
付記1から4のいずれか1項に記載の無線通信システム。
(付記6)
前記無線制御装置は、送信データに対してチャネル符号化処理を行って、チャネル符号化処理が施された送信データを、変調処理の単位であるシンボル毎に分割して、前記無線装置に送信し、
前記無線装置は、前記無線制御装置から送信された送信データに対し、シンボル単位で変調処理を行う
付記1から4のいずれか1項に記載の無線通信システム。
(付記7)
前記無線制御装置は、
スケジューリング処理が終了する前に送信データを前記無線装置に送信し、
前記スケジューリング処理が終了した後、スケジューリング結果を示すスケジューリング結果指示信号を前記無線装置に送信し、
前記無線装置は、
前記無線制御装置から送信された送信データを格納し、
前記スケジューリング結果指示信号に基づいて、前記格納された送信データのうち、前記無線端末に対して、当該無線端末に送信すべきデータを示す無線信号を送信する
付記1から4のいずれか1項に記載の無線通信システム。
(付記8)
無線制御装置と、
無線端末と無線通信を行う少なくとも1つの無線装置と、
前記無線制御装置と前記無線装置との間に設けられ、前記無線制御装置と第1の伝送路を介して接続され、前記無線装置と第2の伝送路を介して接続された中継装置と
を有し、
前記無線制御装置は、
前記無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを割り当てる無線リソース割当手段と、
前記割り当てられた前記無線リソースを使用させるための指示を前記中継装置に対して送信する無線リソース指示手段と
を有し、
前記中継装置は、前記無線制御装置からの指示に基づいて、前記無線端末に送信すべきデータに対して、前記割り当てられた無線リソースを用いて無線通信を行うための処理を行い、
前記無線装置は、前記無線信号処理手段によって処理された信号を無線信号に変換して、前記無線端末に送信する
無線通信システム。
(付記9)
前記中継装置は、チャネル符号化処理及びチャネル復号化処理と、変調処理及び復調処理とを行う
付記8に記載の無線通信システム。
(付記10)
前記中継装置は、送信データに対してチャネル符号化処理を行って、チャネル符号化処理が施された送信データを、変調処理の単位であるシンボル毎に分割して、前記無線装置に送信し、
前記無線装置は、前記無線制御装置から送信された送信データに対し、シンボル単位で変調処理を行う
付記8に記載の無線通信システム。
(付記11)
無線制御装置と、前記無線制御装置と伝送路を介して接続され、無線端末と無線通信を行う少なくとも1つの無線装置とを有する無線通信システムにおける無線通信方法であって、
前記無線制御装置において、
前記無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを割り当て、
前記割り当てられた前記無線リソースを使用させるための指示を前記無線装置に対して送信し、
前記無線装置において、
前記無線制御装置からの指示に基づいて、前記無線端末に送信すべきデータに対して、前記割り当てられた無線リソースを用いて無線通信を行うための処理を行い、
前記無線信号処理手段によって処理された信号を無線信号に変換して、前記無線端末に送信する
無線通信方法。
(付記12)
無線端末と無線通信を行う少なくとも1つの無線装置と伝送路を介して接続された無線制御装置であって、
前記無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを割り当てる無線リソース割当手段と、
前記割り当てられた前記無線リソースを使用させるための指示を前記無線装置に対して送信する無線リソース指示手段と
を有する無線制御装置。
(付記13)
複数の前記無線装置のうち、前記無線端末と無線通信を行わせる前記無線装置を選択する無線装置選択手段
をさらに有する付記12に記載の無線制御装置。
(付記14)
前記複数の無線装置を協調動作させるように制御する無線装置制御手段
をさらに有する付記13に記載の無線制御装置。
(付記15)
無線端末と無線通信を行い、無線制御装置と伝送路を介して接続された無線装置であって、
前記無線制御装置によって送信された、当該無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを使用させるための指示に基づいて、前記無線端末に送信すべきデータに対して、前記無線リソースを用いて無線通信を行うための処理を行う無線信号処理手段と、
前記無線信号処理手段によって処理された信号を無線信号に変換して、前記無線端末に送信する無線送信手段と
を有する無線装置。
(付記16)
複数のアンテナを有し、
前記無線信号処理手段は、前記複数のアンテナそれぞれについてアンテナ重み付け処理を行う
付記15に記載の無線装置。
(付記17)
無線制御装置と、無線端末と無線通信を行う少なくとも1つの無線装置との間に設けられ、
前記無線制御装置と第1の伝送路を介して接続され、前記無線装置と第2の伝送路を介して接続され、
前記無線制御装置によって送信された、前記無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを使用させるための指示に基づいて、前記無線端末に送信すべきデータに対して、前記無線リソースを用いて無線通信を行うための処理を行う
中継装置。
(付記18)
無線端末と無線通信を行う少なくとも1つの無線装置と伝送路を介して接続された無線制御装置における無線通信方法であって、
前記無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを割り当て、
前記割り当てられた前記無線リソースを使用させるための指示を前記無線装置に対して送信する
無線通信方法。
(付記19)
無線端末と無線通信を行い、無線制御装置と伝送路を介して接続された無線装置における無線通信方法であって、
前記無線制御装置によって送信された、当該無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを使用させるための指示に基づいて、前記無線端末に送信すべきデータに対して、前記無線リソースを用いて無線通信を行うための処理を行い、
前記処理された信号を無線信号に変換して、前記無線端末に送信する
無線通信方法。
(付記20)
無線制御装置と、無線端末と無線通信を行う少なくとも1つの無線装置との間に設けられた中継装置における無線通信方法であって、
前記無線制御装置によって送信された、前記無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを使用させるための指示に基づいて、前記無線端末に送信すべきデータに対して、前記無線リソースを用いて無線通信を行うための処理を行う
無線通信方法。
10 伝送路
20 無線制御装置
22 無線リソース割当部
24 無線リソース指示部
30 無線装置
32 無線信号処理部
34 無線送信部
100 無線通信システム
102 バックホール
104 コアネットワーク
110 伝送路
112 伝送路
120 無線端末
150 無線通信システム
200 センターノード
202 基準クロック生成部
204 汎用サーバ
206 伝送路インタフェース
210 ソフトウェア
212 同期処理部
214 無線回線品質管理部
216 アクセスポイント選択部
218 無線リソース管理部
220 無線リソース割当部
222 アクセスポイント制御部
240 PDCP処理部
250 RLC処理部
260 MAC処理部
300 アクセスポイント
302 伝送路インタフェース
304 無線送受信部
306 アンテナ
310 無線信号処理部
312 チャネル符号化部
314 変調部
316 物理アンテナマッピング部
322 物理アンテナ合成部
324 復調部
326 チャネル復号化部
342 ユーザ処理部
344 制御チャネル・信号処理部
352 リソースエレメントマッピング部
354 OFDMシンボル生成部
356 物理アンテナマッピング部
362 チャネル符号化部
364 変調マッピング部
366 レイヤマッピング部
368 プリコーディング部
372 リソースエレメントマッピング部
374 OFDMシンボル生成部
376 物理アンテナマッピング部
378 ビームフォーミング部
380 HARQバッファ
382 データバッファ
400 中継ノード
402 伝送路インタフェース
404 伝送路インタフェース
410 無線信号処理部
500 第2アクセスポイント
502 伝送路インタフェース
504 無線送受信部
506 アンテナ
Claims (10)
- 無線制御装置と、
前記無線制御装置と伝送路を介して接続され、無線端末と無線通信を行う少なくとも1つの無線装置と
を有し、
前記無線制御装置は、
前記無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを割り当てる無線リソース割当手段と、
前記割り当てられた前記無線リソースを使用させるための指示を前記無線装置に対して送信する無線リソース指示手段と
を有し、
前記無線装置は、
前記無線制御装置からの指示に基づいて、前記無線端末に送信すべきデータに対して、前記割り当てられた無線リソースを用いて無線通信を行うための処理を行う無線信号処理手段と、
前記無線信号処理手段によって処理された信号を無線信号に変換して、前記無線端末に送信する無線送信手段と
を有する
無線通信システム。 - 前記無線装置は複数設けられており、
前記無線制御装置は、
前記無線端末と無線通信を行わせる前記無線装置を選択する無線装置選択手段
をさらに有し、
前記選択された無線装置は、前記無線端末と無線通信を行う
請求項1に記載の無線通信システム。 - 前記無線制御装置は、
前記複数の無線装置を協調動作させるように制御する無線装置制御手段
をさらに有し、
前記複数の無線装置は、前記無線装置制御手段の制御により、協調動作を行う
請求項2に記載の無線通信システム。 - 前記無線装置は、複数のアンテナを有し、
前記無線信号処理手段は、前記複数のアンテナそれぞれについてアンテナ重み付け処理を行う
請求項1から3のいずれか1項に記載の無線通信システム。 - 前記無線信号処理手段は、チャネル符号化処理及びチャネル復号化処理と、変調処理及び復調処理とを行う
請求項1から4のいずれか1項に記載の無線通信システム。 - 前記無線制御装置は、送信データに対してチャネル符号化処理を行って、チャネル符号化処理が施された送信データを、変調処理の単位であるシンボル毎に分割して、前記無線装置に送信し、
前記無線装置は、前記無線制御装置から送信された送信データに対し、シンボル単位で変調処理を行う
請求項1から4のいずれか1項に記載の無線通信システム。 - 前記無線制御装置は、
スケジューリング処理が終了する前に送信データを前記無線装置に送信し、
前記スケジューリング処理が終了した後、スケジューリング結果を示すスケジューリング結果指示信号を前記無線装置に送信し、
前記無線装置は、
前記無線制御装置から送信された送信データを格納し、
前記スケジューリング結果指示信号に基づいて、前記格納された送信データのうち、前記無線端末に対して、当該無線端末に送信すべきデータを示す無線信号を送信する
請求項1から4のいずれか1項に記載の無線通信システム。 - 無線制御装置と、
無線端末と無線通信を行う少なくとも1つの無線装置と、
前記無線制御装置と前記無線装置との間に設けられ、前記無線制御装置と第1の伝送路を介して接続され、前記無線装置と第2の伝送路を介して接続された中継装置と
を有し、
前記無線制御装置は、
前記無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを割り当てる無線リソース割当手段と、
前記割り当てられた前記無線リソースを使用させるための指示を前記中継装置に対して送信する無線リソース指示手段と
を有し、
前記中継装置は、前記無線制御装置からの指示に基づいて、前記無線端末に送信すべきデータに対して、前記割り当てられた無線リソースを用いて無線通信を行うための処理を行い、
前記無線装置は、前記無線信号処理手段によって処理された信号を無線信号に変換して、前記無線端末に送信する
無線通信システム。 - 前記中継装置は、送信データに対してチャネル符号化処理を行って、チャネル符号化処理が施された送信データを、変調処理の単位であるシンボル毎に分割して、前記無線装置に送信し、
前記無線装置は、前記無線制御装置から送信された送信データに対し、シンボル単位で変調処理を行う
請求項8に記載の無線通信システム。 - 無線端末と無線通信を行う少なくとも1つの無線装置と伝送路を介して接続された無線制御装置において、
前記無線装置が前記無線端末と無線通信を行う際に使用される無線リソースを割り当て、
前記割り当てられた前記無線リソースを使用させるための指示を前記無線装置に対して送信し、
前記無線装置において、
前記無線制御装置からの指示に基づいて、前記無線端末に送信すべきデータに対して、前記割り当てられた無線リソースを用いて無線通信を行うための処理を行い、
前記無線信号処理手段によって処理された信号を無線信号に変換して、前記無線端末に送信する
無線通信方法。
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Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016203918A1 (ja) * | 2015-06-18 | 2016-12-22 | 株式会社Nttドコモ | 基地局システムおよび制御装置 |
WO2017163785A1 (ja) * | 2016-03-24 | 2017-09-28 | 株式会社Nttドコモ | 無線基地局、張出装置及び通信制御方法 |
WO2017163784A1 (ja) * | 2016-03-24 | 2017-09-28 | 株式会社Nttドコモ | 無線基地局及び通信制御方法 |
WO2017175478A1 (ja) * | 2016-04-08 | 2017-10-12 | 株式会社Nttドコモ | 無線基地局及び通信制御方法 |
WO2018078677A1 (ja) * | 2016-10-31 | 2018-05-03 | 日本電気株式会社 | 通信装置、通信システム、通信方法、及び非一時的なコンピュータ可読媒体 |
CN108476477A (zh) * | 2016-01-22 | 2018-08-31 | 株式会社Ntt都科摩 | 无线基站以及通信控制方法 |
WO2018198963A1 (ja) * | 2017-04-27 | 2018-11-01 | 三菱電機株式会社 | 通信システム |
JP2019507966A (ja) * | 2016-02-05 | 2019-03-22 | グァンドン オッポ モバイル テレコミュニケーションズ コーポレーション リミテッド | ハンドオーバのためのリソース構成方法、ネットワークアクセスポイント及び移動局 |
CN109565901A (zh) * | 2016-08-12 | 2019-04-02 | 富士通株式会社 | 无线基站、无线装置、无线控制装置、无线通信系统、通信方法以及无线终端 |
JPWO2017217024A1 (ja) * | 2016-06-14 | 2019-05-16 | 株式会社Nttドコモ | 通信システム |
WO2020022330A1 (ja) * | 2018-07-24 | 2020-01-30 | 日本電信電話株式会社 | 中継装置及び中継方法 |
JP2020513184A (ja) * | 2017-04-07 | 2020-04-30 | 華為技術有限公司Huawei Technologies Co.,Ltd. | 基地局機能配備方法及び装置 |
JP2022507899A (ja) * | 2018-11-23 | 2022-01-18 | シグニファイ ホールディング ビー ヴィ | 複数のコーディネータを有するワイヤレス光ネットワークのための干渉のないスケジューリング |
Families Citing this family (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10484074B2 (en) * | 2015-08-25 | 2019-11-19 | Cellium Technologies, Ltd. | Systems and methods for maximizing data transmission rates in conjunction with a spatial-multiplexing transmission |
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JP2017050730A (ja) * | 2015-09-02 | 2017-03-09 | 富士通株式会社 | 無線装置および基地局システム |
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US10979908B2 (en) * | 2018-08-17 | 2021-04-13 | Charter Communications Operating, Llc | Monitoring and switchover of shared spectrum allocation manager to provide improved wireless service |
US10932143B2 (en) | 2018-08-17 | 2021-02-23 | Charter Communications Operating, Llc | Monitoring and switchover of shared spectrum allocation manager in a wireless network |
WO2020081404A1 (en) * | 2018-10-15 | 2020-04-23 | Blue Danube Systems, Inc. | Enhancing throughput using agile beam switching and user scheduling in cellular systems |
EP3935916A4 (en) * | 2019-03-07 | 2022-11-30 | CommScope Technologies LLC | BASEBAND CONTROL FOR A CENTRALIZED RADIO ACCESS NETWORK (C-RAN) IMPLEMENTED USING A HYBRID VIRTUALIZATION ARCHITECTURE |
JP2022065564A (ja) * | 2020-10-15 | 2022-04-27 | トヨタ自動車株式会社 | 基地局および通信方法 |
CN114095099B (zh) * | 2021-11-26 | 2023-12-22 | 深圳市联平半导体有限公司 | 信号的生成方法、生成装置及生成设备 |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2012019468A (ja) * | 2010-07-09 | 2012-01-26 | Fujitsu Ltd | セル識別子の決定方法、無線基地局及び無線通信システム |
JP2013243454A (ja) * | 2012-05-18 | 2013-12-05 | Sharp Corp | 通信システム及び通信方法 |
JP2014030135A (ja) * | 2012-07-31 | 2014-02-13 | Ntt Docomo Inc | 基地局装置、ユーザ端末、通信システム及び通信制御方法 |
JP2014112976A (ja) * | 2010-11-05 | 2014-06-19 | Hitachi Ltd | 無線通信システム、基地局及び無線通信方法 |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FI981575A (fi) * | 1998-07-08 | 2000-01-09 | Nokia Networks Oy | Menetelmä ja järjestelmä digitaalisen signaalin siirtämiseksi |
JP2004312150A (ja) | 2003-04-03 | 2004-11-04 | Nippon Telegr & Teleph Corp <Ntt> | ディジタルファイバ無線伝送システム |
US7831256B2 (en) * | 2003-06-25 | 2010-11-09 | Nec Corporation | Mobile communication system and access control method |
JP4750646B2 (ja) * | 2006-08-14 | 2011-08-17 | 株式会社エヌ・ティ・ティ・ドコモ | 移動通信システム及び通信路設定方法 |
KR20100125693A (ko) * | 2009-05-21 | 2010-12-01 | 삼성전자주식회사 | 무선통신시스템에서 셀 간 간섭을 감소시키기 위한 장치 및 방법 |
CN102546080B (zh) * | 2010-12-21 | 2014-06-25 | 华为技术有限公司 | 一种下行基带信号生成方法及相关设备、系统 |
CN102907167B (zh) | 2011-05-17 | 2016-01-20 | 华为技术有限公司 | 通信系统及其管理方法 |
-
2015
- 2015-06-24 JP JP2016530822A patent/JP6414216B2/ja active Active
- 2015-06-24 US US15/319,125 patent/US10039099B2/en active Active
- 2015-06-24 EP EP15815230.6A patent/EP3163974B1/en active Active
- 2015-06-24 CN CN201580046763.2A patent/CN106797675B/zh active Active
- 2015-06-24 WO PCT/JP2015/003183 patent/WO2016002166A1/ja active Application Filing
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2012019468A (ja) * | 2010-07-09 | 2012-01-26 | Fujitsu Ltd | セル識別子の決定方法、無線基地局及び無線通信システム |
JP2014112976A (ja) * | 2010-11-05 | 2014-06-19 | Hitachi Ltd | 無線通信システム、基地局及び無線通信方法 |
JP2013243454A (ja) * | 2012-05-18 | 2013-12-05 | Sharp Corp | 通信システム及び通信方法 |
JP2014030135A (ja) * | 2012-07-31 | 2014-02-13 | Ntt Docomo Inc | 基地局装置、ユーザ端末、通信システム及び通信制御方法 |
Non-Patent Citations (1)
Title |
---|
See also references of EP3163974A4 * |
Cited By (42)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016203918A1 (ja) * | 2015-06-18 | 2016-12-22 | 株式会社Nttドコモ | 基地局システムおよび制御装置 |
CN108476477A (zh) * | 2016-01-22 | 2018-08-31 | 株式会社Ntt都科摩 | 无线基站以及通信控制方法 |
EP3407649A4 (en) * | 2016-01-22 | 2019-08-21 | NTT DoCoMo, Inc. | RADIO BASIS STATION AND COMMUNICATION CONTROL METHOD |
JP2019507966A (ja) * | 2016-02-05 | 2019-03-22 | グァンドン オッポ モバイル テレコミュニケーションズ コーポレーション リミテッド | ハンドオーバのためのリソース構成方法、ネットワークアクセスポイント及び移動局 |
US11350326B2 (en) | 2016-02-05 | 2022-05-31 | Guangdong Oppo Mobile Telecommunications Corp., Ltd. | Resource configuration method for switching, network access point, and mobile station |
JPWO2017163784A1 (ja) * | 2016-03-24 | 2019-01-31 | 株式会社Nttドコモ | 無線基地局及び通信制御方法 |
US11540321B2 (en) | 2016-03-24 | 2022-12-27 | Ntt Docomo, Inc. | Radio base station and communication control method |
CN108781477A (zh) * | 2016-03-24 | 2018-11-09 | 株式会社Ntt都科摩 | 无线基站及通信控制方法 |
EP3435703A4 (en) * | 2016-03-24 | 2019-10-16 | NTT DoCoMo, Inc. | WIRELESS BASE STATION, PROTECTIVE DEVICE, AND COMMUNICATION CONTROL METHOD |
WO2017163784A1 (ja) * | 2016-03-24 | 2017-09-28 | 株式会社Nttドコモ | 無線基地局及び通信制御方法 |
EP3435732A4 (en) * | 2016-03-24 | 2020-02-26 | NTT DoCoMo, Inc. | WIRELESS BASE STATION AND COMMUNICATION CONTROL METHOD |
WO2017163785A1 (ja) * | 2016-03-24 | 2017-09-28 | 株式会社Nttドコモ | 無線基地局、張出装置及び通信制御方法 |
JP7169874B2 (ja) | 2016-03-24 | 2022-11-11 | 株式会社Nttドコモ | 無線基地局及び通信制御方法 |
CN109076388A (zh) * | 2016-04-08 | 2018-12-21 | 株式会社Ntt都科摩 | 无线基站以及通信控制方法 |
WO2017175478A1 (ja) * | 2016-04-08 | 2017-10-12 | 株式会社Nttドコモ | 無線基地局及び通信制御方法 |
JPWO2017217024A1 (ja) * | 2016-06-14 | 2019-05-16 | 株式会社Nttドコモ | 通信システム |
JP7038657B2 (ja) | 2016-06-14 | 2022-03-18 | 株式会社Nttドコモ | 通信システム |
CN109565901A (zh) * | 2016-08-12 | 2019-04-02 | 富士通株式会社 | 无线基站、无线装置、无线控制装置、无线通信系统、通信方法以及无线终端 |
CN109565901B (zh) * | 2016-08-12 | 2021-10-22 | 富士通株式会社 | 无线基站、无线装置、无线控制装置、无线通信系统、通信方法以及无线终端 |
JPWO2018078677A1 (ja) * | 2016-10-31 | 2019-09-05 | 日本電気株式会社 | 通信装置、通信システム、通信方法、及び非一時的なコンピュータ可読媒体 |
US11412526B2 (en) | 2016-10-31 | 2022-08-09 | Nec Corporation | Communication apparatus, communication system, communication method, and non-transitory computer readable medium |
US20200059942A1 (en) * | 2016-10-31 | 2020-02-20 | Nec Corporation | Communication apparatus, communication system, communication method, and non-transitory computer readable medium |
US10986649B2 (en) | 2016-10-31 | 2021-04-20 | Nec Corporation | Communication apparatus, communication system, communication method, and non-transitory computer readable medium |
WO2018078677A1 (ja) * | 2016-10-31 | 2018-05-03 | 日本電気株式会社 | 通信装置、通信システム、通信方法、及び非一時的なコンピュータ可読媒体 |
JP7056872B2 (ja) | 2016-10-31 | 2022-04-19 | 日本電気株式会社 | 通信装置、通信システム、通信方法、及びプログラム |
JP2020513184A (ja) * | 2017-04-07 | 2020-04-30 | 華為技術有限公司Huawei Technologies Co.,Ltd. | 基地局機能配備方法及び装置 |
US11109450B2 (en) | 2017-04-07 | 2021-08-31 | Huawei Technologies Co., Ltd. | Base station function deployment method and device |
JPWO2018198963A1 (ja) * | 2017-04-27 | 2020-03-12 | 三菱電機株式会社 | 通信システム |
US11228940B2 (en) | 2017-04-27 | 2022-01-18 | Mitsubishi Electric Corporation | Communication system |
US11871268B2 (en) | 2017-04-27 | 2024-01-09 | Mitsubishi Electric Corporation | Communication system |
EP4236616A3 (en) * | 2017-04-27 | 2023-12-13 | Mitsubishi Electric Corporation | Communication system |
JP7313281B2 (ja) | 2017-04-27 | 2023-07-24 | 三菱電機株式会社 | 通信システム |
WO2018198963A1 (ja) * | 2017-04-27 | 2018-11-01 | 三菱電機株式会社 | 通信システム |
US11509357B2 (en) | 2018-07-24 | 2022-11-22 | Nippon Telegraph And Telephone Corporation | Relay apparatus and relay method |
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JP7078851B2 (ja) | 2018-07-24 | 2022-06-01 | 日本電信電話株式会社 | 中継装置及び中継方法 |
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US11552705B2 (en) | 2018-11-23 | 2023-01-10 | Signify Holding B.V. | Interference-free scheduling for wireless optical networks with multiple coordinators |
JP2023017785A (ja) * | 2018-11-23 | 2023-02-07 | シグニファイ ホールディング ビー ヴィ | 複数のコーディネータを有するワイヤレス光ネットワークのための干渉のないスケジューリング |
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