JP7005190B2 - Signal processing equipment, radio equipment, fronthaul multiplexers, beam control methods, and signal synthesis methods - Google Patents

Description

The present invention relates to signal processing devices, radio devices, fronthaul multiplexers, beam control methods, and signal synthesis methods.

In the wireless network system, C-RAN (Centralized Radio Access Network) has been developed, which enables more comfortable and stable high-speed communication. In C-RAN, a wireless base station is separated into a wireless device that performs wireless communication with a user terminal and a signal processing device that controls this wireless device, and the signal processing device integrates functions such as baseband signal processing (for example). , Patent Documents 1 and 2).

In addition, an advanced C-RAN, which is an advanced version of C-RAN, has also been developed. In the advanced C-RAN, a wide area service area is constructed with macro cells, and a narrow service area is constructed with small cells. In the advanced C-RAN, a CC (Component Carrier) different from the macro cell is provided in the area of the small cell, and the bandwidth is widened by CA (Carrier Aggregation) between the CC of the macro cell and the CC of the small cell. To realize.

A fronthaul multiplexer (FHM) that multiplexes fronthaul lines has also been developed to accommodate more radio devices in a single signal processing device (see, for example, Non-Patent Document 1). The FHM is connected between the signal processing device and the plurality of wireless devices, and for example, the downlink signal is copied in cell units and distributed to the plurality of wireless devices. Further, the FHM, for example, synthesizes uplink signals from a plurality of wireless devices and transmits them to a signal processing device.

Japanese Unexamined Patent Publication No. 2017-38887 Special Table 2016-510587A Gazette Fujii, Suwa, Toba, Toeda "Development of base station equipment for introduction of 3.5GHz band TD-LTE" NTT DOCOMO Technical Journal, Jul. 2016, vol. 24 No. 2 pp. 8-13

In a wireless communication system using FHM, it is conceivable to perform BF (Beam Forming). In this case, it is conceivable that the signal processing device transmits a BFI (Beam Forming Indicator) that identifies the beam direction to the FHM, and the FHM transmits the BFI to each wireless device. Since the BFI is copied by FHM and transmitted to each radio device, each radio device under FHM controls the beam direction based on the same BFI.

As described above, when a plurality of wireless devices control the beam direction based on the same BFI transmitted from the FHM, there is a problem that the beam direction of each wireless device cannot be controlled individually (independently).

An object of the present invention is to provide a technique capable of individually controlling the beam direction of each wireless device under FHM.

The signal processing device of the present invention is a signal processing device that communicates via a plurality of wireless devices that perform wireless communication with a user terminal and a front hall multiplexer, and device identification information of the plurality of wireless devices and each radio. A storage unit that stores beam identification information assigned to each beam so as to be different among the beams formed by the apparatus, and beam information associated with the beam information, and the beam information are stored in the plurality of beam information via the front hole multiplexer. The transmission unit that transmits to the wireless device and the beam identification information assigned to the beam having the best communication quality received from the user terminal by the plurality of wireless terminals are transmitted to the plurality of wireless terminals via the front hall multiplexer. It has a receiving unit that receives from.

The wireless device of the present invention is a wireless device that communicates with a signal processing device via a front hall multiplexer and wirelessly communicates with a user terminal, and is formed by device identification information of a plurality of wireless devices and each wireless device. From the beam information receiving unit and the beam information, which receives the beam information associated with the beam identification information assigned to each beam so as to be different between the beams from the signal processing device via the front hole multiplexer. The beam identification information is obtained by sweeping the beam using the acquisition unit that acquires the beam identification information corresponding to the device identification information of the own machine and each beam identified by the acquired beam identification information. The front of the sweep unit that transmits to the user terminal, the beam identification information receiving unit that receives the beam identification information assigned to the beam having the best communication quality from the user terminal, and the received beam identification information. It has a beam identification information transmitting unit that transmits to the signal processing device via a hall multiplexer.

The front-hole multiplexer of the present invention is a front-hole multiplexer that relays communication between a signal processing device and a plurality of wireless devices, and device identification information of the plurality of wireless devices and a beam formed by each wireless device. A user terminal that wirelessly communicates with a beam information receiving unit that receives beam information associated with beam identification information assigned to each beam so as to be different between the signal processing devices and the plurality of wireless devices. The device identification information corresponding to the beam identification information of the uplink included in the scheduling information is acquired from the scheduling information receiving unit that receives the scheduling information from the signal processing device and the beam information. From the device identification information, the specific unit that identifies the wireless device under the control of the user terminal, the synthesis unit that synthesizes the uplink signal transmitted from the specified wireless device, and the synthesized uplink signal are described above. It has a transmission unit for transmitting to a signal processing device.

According to the present invention, when BFI is transmitted to each radio device via FHM, the beam direction of each radio device can be individually controlled.

It is a figure which showed the configuration example of the radio base station which concerns on 1st Embodiment. It is a figure explaining the schematic operation of FHM. It is a figure explaining the example of the throughput when FHM is not connected between CU and DU, and the throughput when FHM is connected between CU and DU. It is a figure which showed the block example of CU of FIG. It is a figure which showed the data composition example of the beam information stored in the storage part. It is a figure which showed the block example of DU of FIG. It is a figure explaining the acquisition of the beam identification information of DU. It is a figure explaining the sweeping of a beam. It is a figure explaining the feedback of the beam identification information. It is a figure explaining the example of the sweep timing of a beam. It is a figure explaining the example of data transmission to a user terminal. It is a figure which showed the block example of FHM which concerns on 2nd Embodiment. It is a figure explaining the signal synthesis example of FHM. It is a figure explaining the signal synthesis example of FHM. It is a figure which shows an example of the hardware composition of the CU, DU, FHM, and the user terminal which concerns on this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a diagram showing a configuration example of a radio base station according to the first embodiment. As shown in FIG. 1, the radio base station has a CU (Centralized Unit) 1, an FHM 2, and DUs (Distributed Units) 3a to 3c. FIG. 1 also shows user terminals 4a to 4c that perform wireless communication with DU3a to 3c. The radio base station shown in FIG. 1 forms, for example, an advanced C-RAN.

CU1 and FHM2 are connected by, for example, an optical fiber. FHM2 and DU3a to 3c are connected by, for example, an optical fiber.

CU1 is connected to a core network (not shown). The CU 1 transmits a signal (data) received from the core network to the FHM 2. Further, the CU 1 transmits the signal received from the FHM 2 to the core network. The CU 1 performs signal baseband processing, maintenance monitoring processing of DU3a to 3c, and the like.

The FHM 2 multiplexes the front hole line between the CU 1 and the plurality of DUs 3a to 3c. For example, FHM2 copies the signal received from CU1 and transmits it to DU3a to 3c. Further, FHM2 synthesizes the signals received from DU3a to 3cc and transmits them to CU1.

The DUs 3a to 3c transmit the signals received from the CU1 to the user terminals 4a to 4c via the FHM2. Further, the DUs 3a to 3c transmit the signals received from the user terminals 4a to 4bc to the CU1 via the FHM2.

The DUs 3a to 3c have, for example, tens to hundreds of antennas and perform wireless communication with the user terminals 4a to 4c. The DUs 3a to 3c use a plurality of antennas to control the amplitude and phase of the signal, form a directional beam on the user terminals 4a to 4c, and transmit and receive the signal. DU3a-3c can form beams in various directions.

Although the radio base station in FIG. 1 is supposed to form an advanced C-RAN, it may form a C-RAN. Further, in FIG. 1, only one FHM2 is connected under the control of the CU 1, but a plurality of FHM2s may be connected.

Further, the CU 1 may be referred to as, for example, a BDE (Base station Digital processing Equipment), a BBU (Base Band Unit), a radio control device, a master station, or a signal processing device. Further, the DUs 3a to 3c may be referred to as, for example, an RRH (Remote Radio Head), a slave station, or a wireless device.

FIG. 2 is a diagram illustrating a schematic operation of the FHM 2. In FIG. 2, the same components as those in FIG. 1 are designated by the same reference numerals.

The signal S1 shown in FIG. 2 indicates a DL (Down Link) signal transmitted from the CU 1 to the DUs 3a to 3c. The signal S1 is copied by the FHM2 and transmitted to the DU3a to 3c as shown in the signals S2a to S2c.

The signals S3a to 3c shown in FIG. 2 indicate UL (Up Link) signals transmitted from the DUs 3a to 3c to the CU1. The signals S3a to 3c are synthesized by the FHM2 and transmitted to the CU1 as shown in the signal S4.

In this way, the FHM2 copies the DL signal transmitted from the CU1 to the DU3a to 3c. Further, FHM2 synthesizes a UL signal transmitted from DU3a to 3c to CU1. As a result, the CU 1 can accommodate a plurality of DU3a to 3c as one cell.

FIG. 3 is a diagram illustrating an example of the throughput when the FHM is not connected between the CU and the DU and the throughput when the FHM is connected between the CU and the DU.

CU11a and 11b are shown in FIG. It is assumed that eight DUs (not shown) are connected to CU11a without going through FHM. Further, it is assumed that eight DUs (not shown) are connected to the CU 11b without going through FHM.

Further, FIG. 3 shows CU21 and FHM22a and 22b. It is assumed that eight DUs (not shown) are connected to the FHM22a. Further, it is assumed that eight DUs (not shown) are connected to the FHM22b.

Throughput 12a (8 cylinders) indicates the standard peak throughput between the CU 11a and the 8 DUs. The hatched portion shown in the throughput 12a indicates the instantaneous throughput (throughput at a certain time) between the CU 11a and the eight DUs.

Throughput 12b (8 cylinders) indicates the standard peak throughput between CU11b and 8 DUs. The hatched portion shown in the throughput 12b indicates the instantaneous throughput between the CU 11b and the eight DUs.

Throughput 23a (8 cylinders) indicates the instantaneous throughput between the FHM 22a and the 8 DUs. Throughput 24a indicates the instantaneous throughput between CU21 and FHM22a. Since the FHM 22a copies the DL signal and synthesizes the UL signal as described in FIG. 2, the instantaneous throughput between the CU 21 and the FHM 22a is the throughput 23a (8 lines) as shown in the throughput 24a. It is the total throughput of the cylinders).

Throughput 23b (8 cylinders) indicates the instantaneous throughput between the FHM 22b and the 8 DUs. Throughput 24b indicates the instantaneous throughput between CU21 and FHM22b. Since the FHM 22b copies the DL signal and synthesizes the UL signal as described in FIG. 2, the instantaneous throughput between the CU 21 and the FHM 22b is as shown in the throughput 24b, that is, the throughput 23b (8 lines). It is the total throughput of the cylinders).

When the FHM is not connected between the CU and the DU, the CU and the DU may have a margin for the peak throughput as shown in the throughputs 12a and 12b of FIG. 3, and the resources are not used efficiently. In some cases. On the other hand, when the FHM is connected between the CU and the DU, the CU and the DU can efficiently use the resources as shown in the throughputs 24a and 24b of FIG.

In the next-generation wireless communication system (for example, 5G), it is considered to use a high frequency band of, for example, several GHz to several tens of GHz as the radio frequency. As the radio frequency increases, the straightness of the radio wave increases, and it becomes difficult for the radio wave to reach the user terminal due to the shadow of a building or the like. Therefore, in the next-generation wireless communication system, it is considered to increase the DU to make the area smaller and perform wireless communication by beamforming.

In response to such an increase in DUs, wireless base stations can accommodate more DUs in one CU in a small area in a place where the required wireless capacity is small by using FHM. Become. For example, in the example of the CU 21 using the FHM 22a and 22b in FIG. 3, 16 DUs are housed in one CU 21. That is, the radio base station can increase the number of DUs with a small investment by using FHM. For example, a small investment can increase the 5G area. When FHM is used, in the example of FIG. 3, 64 DUs can be accommodated under one FHM.

FIG. 4 is a diagram showing a block example of CU1 in FIG. As shown in FIG. 4, the CU 1 includes a control unit 31, a storage unit 32, an I / F unit 33, a transmission signal generation unit 34, a coding / modulation unit 35, a mapping unit 36, and a transmission unit 37. It has a receiving unit 38, a demapping unit 39, a channel estimation unit 40, a demodulation / decoding unit 41, and a communication quality acquisition unit 42.

The control unit 31 schedules the DL signal based on the communication quality between the DU 3a to 3c and the user terminals 4a to 4c output from the communication quality acquisition unit 42. The DL signal includes a DL data signal and a DL control signal. The DL data signal is transmitted using, for example, PDSCH (Physical Downlink Shared Channel). The DL control signal is transmitted using, for example, a PDCCH (Physical Downlink Control Channel).

Further, the control unit 31 schedules the UL signal based on the communication quality between the DU 3a to 3c and the user terminals 4a to 4c output from the communication quality acquisition unit 42. UL signals include UL data signals and UL control signals. The UL data signal is transmitted using, for example, PUSCH (Physical Uplink Shared Channel). The UL control signal is transmitted using, for example, a PUCCH (Physical Uplink Control Channel).

Further, the control unit 31 MCS (Modulation and Coding Scheme) of the DL data signal and the UL data signal based on the communication quality between the DU 3a to 3c and the user terminals 4a to 4c output from the communication quality acquisition unit 42. ) Etc. are decided. The MCS is not limited to the case where the CU1 is set, and the user terminals 4a to 4c may be set. When the user terminals 4a to 4c set the MCS, the CU 1 may receive the MCS information from the user terminals 4a to 4c.

Further, the control unit 31 transmits the beam information stored in the storage unit 32 described below to the DUs 3a to 3c via the FHM2. For example, the control unit 31 includes the beam information 51 stored in the storage unit 32 in the DL control signal and transmits the beam information 51 to the DUs 3a to 3c. Alternatively, the control unit 31 includes the beam information 51 stored in the storage unit 32 in, for example, a signal for maintaining or monitoring the DUs 3a to 3c, and transmits the beam information 51 to the DUs 3a to 3c.

The control unit 31 outputs the generated DL signal and UL signal scheduling information to the transmission signal generation unit 34 and the mapping unit 36. Further, the control unit 31 outputs the generated MCS information to the transmission signal generation unit 34 and the coding / modulation unit 35.

The storage unit 32 stores beam information that identifies the direction of the beam formed by the DUs 3a to 3c. The beam information is stored in the storage unit 32 in advance, for example. The beam information is updated, for example, when a new DU is connected to the FHM2 or when the DU is changed (replaced). The beam information may be transmitted from, for example, a host device and stored in the storage unit 32.

FIG. 5 is a diagram showing a data configuration example of beam information stored in the storage unit 32. As shown in FIG. 5, the beam information 51 has DU identification information 51a and beam identification information 51b.

The DU identification information 51a is unique identification information that identifies a plurality of DU3a to 3c. For example, "DU # 1" shown in FIG. 5 is an identifier given to DU3a shown in FIG. 1, and "DU # 2" is an identifier given to DU3b. Further, "DU # n" shown in FIG. 5 is, for example, an identifier given to DU3c.

The beam identification information 51b is assigned to each beam differently among the beams formed by each DU3a to 3c (for example, the beam identification information 51b is assigned differently to each of the beams 71a to 71d, 72a to 72d, and 73a to 73d shown in FIG. 8). ), Identification information that identifies the beam direction. In other words, the beam identification information 51b is unique information across a plurality of DU3a to 3c (DU identification information 51a). At least one or more beam identification information 51b is associated with each of the DU identification information 51a and stored in the storage unit 32.

For example, the beam identification information 51b "BFI1 to BFI4" shown in FIG. 5 is associated with the DU identification information 51a "DU # 1", and the beam identification information 51b "BFI5 to BFI8" is the DU identification information 51a. It is associated with "DU # 2". Further, for example, "BFIm-3 to BFIm" of the beam identification information 51b shown in FIG. 5 are associated with "DU # n" of the DU identification information 51a. The "BFI1, BFI2, ..., BFIm-1, BFIm" of the beam identification information 51b is unique information over the "DU # 1 to DU # n" of the DU identification information 51a.

In FIG. 5, four beam identification information 51b are associated with each of the DU identification information 51a, but the present invention is not limited to this. For example, the number of beam identification information 51b associated with the DU identification information 51a may depend on the number of beam directions in which the DUs 3a to 3c can be formed.

Returning to the description of FIG. The I / F unit 33 communicates with a higher-level device connected to the core network. For example, the I / F unit 33 receives data from the host device and outputs the data to the transmission signal generation unit 34. Further, the I / F unit 33 transmits the data output from the demodulation / decoding unit 41 to the host device. The I / F unit 33 performs processing related to a layer higher than the physical layer or the MAC layer, for example.

The transmission signal generation unit 34 generates a DL signal including a DL data signal and a DL control signal, and outputs the DL signal to the coding / modulation unit 35. The DL data signal includes, for example, data (user data) received by the I / F unit 33. Further, the DL control signal includes the radio resource allocation information of the DL data signal generated by the control unit 31, and the scheduling information including the radio resource allocation information of the UL data signal. Further, the DL control signal includes downlink control information (for example, DCI: Downlink Control Information) including MCS information generated by the control unit 31.

The coding / modulation unit 35 performs coding processing and modulation processing on the DL signal output from the transmission signal generation unit 34 based on the MCS information generated by the control unit 31. The coding / modulation unit 35 outputs the coded and modulated DL signal to the mapping unit 36.

The mapping unit 36 maps the DL signal output from the coding / modulation unit 35 to a predetermined radio resource (DL resource) based on the scheduling information generated by the control unit 31. The mapping unit 36 outputs the DL signal mapped to the radio resource to the transmission unit 37.

The transmission unit 37 electrically-optically converts the DL signal output from the mapping unit 36 and outputs it to the optical fiber (transmits it to the FHM2).

The receiving unit 38 optical-electrically converts the optical signal received from the optical fiber (from FHM2) and outputs it to the demapping unit 39.

The demapping unit 39 is a UL data signal and a UL control signal of the user terminals 4a to 4c from the UL signal output from the receiving unit 38 based on the scheduling information (UL radio resource allocation information) generated by the control unit 31. Is separated (demapping). The demapping unit 39 outputs the demapped UL control signal to the channel estimation unit 40. Further, the demapping unit 39 outputs the demapped UL data signal and the UL control signal to the demodulation / decoding unit 41.

The channel estimation unit 40 estimates the UL channel state based on the reference signal included in the UL control signal output from the demapping unit 39.

The demodulation / decoding unit 41 demodulates and decodes the UL control signal and the UL data signal output from the demapping unit 39 based on the channel state estimated by the channel estimation unit 40. The demodulation / decoding unit 41 outputs the demodulated and decoded UL control signal to the communication quality acquisition unit 42. Further, the demodulation / decoding unit 41 outputs the demodulated and decoded UL data signal to the I / F unit 33.

The communication quality acquisition unit 42 acquires the communication quality of the DL between the DU 3a to 3c and the user terminals 4a to 4c from the UL control signal output from the demodulation / decoding unit 41. The communication quality acquisition unit 42 outputs the acquired communication quality to the control unit 31.

In FIG. 4, the description of the component unit (for example, the precoding unit, the prefiltering unit, etc.) for performing MIMO (multiple-input and multiple-output) processing is omitted. The CU 1 performs precoding on the signal output from the coding / modulation unit 35, for example. Further, the CU 1 performs pre-filtering processing on the signal output from the demapping unit 39, for example.

FIG. 6 is a diagram showing a block example of DU3a of FIG. As shown in FIG. 6, the DU3a includes a receiving unit 61, a control unit 62, digital BF (Beam Forming) units 63 and 68, an IFFT (Inverse Fast Fourier Transform) / CP (Cyclic Prefix) unit 64, and a radio. It has units 65 and 66, an FFT (Fast Fourier Transform) / CP unit 67, and a transmission unit 69.

Since DU3b and 3c have the same blocks as DU3a, the description thereof will be omitted. Further, in FIG. 6, the digital BF unit 63 is provided between the receiving unit 61 and the IFF / CP unit 64, but an analog BF may be provided after the IFF / CP unit 64.

The receiving unit 61 receives the optical signal transmitted from the FHM 2, performs optical-electric conversion, and outputs the optical signal to the control unit 62 and the digital BF unit 63. The signal received by the receiving unit 61 includes a DL signal. Further, the signal received by the receiving unit 61 includes the beam information 51.

As described in detail below, the control unit 62 refers to the beam information 51 received by the receiving unit 61 based on the DU identification information assigned to the own unit, and corresponds to the DU identification information of the own unit. The beam identification information 51b is acquired. Then, the control unit 62 controls the digital BF unit 63 and sweeps the beam output from the antenna.

The digital BF unit 63 multiplies the signal received by the receiving unit 61 by the BF weight corresponding to the beam identification information 51b (BFI) fed back from the user terminals 4a to 4c. The digital BF unit 63 outputs a signal multiplied by the BF weight to the IFF / CP unit 64. The feedback of the beam identification information 51b will be described in detail below.

The IFFT / CP unit 64 performs an IFFT process on the signal output from the digital BF unit 63, and adds a CP. The Fourier / CP unit 64 performs the Fourier process and outputs a signal to which the CP is added to the wireless unit 65.

The wireless unit 65 performs wireless transmission processing such as D / A conversion, up-conversion, and signal amplification on the signal output from the IFFT / CP unit 64. The wireless unit 65 outputs a signal processed by wireless transmission to an antenna (not shown).

The radio unit 66 performs radio reception processing such as signal amplification, down conversion, and A / D conversion on the signal received by the antenna (not shown). The wireless unit 66 outputs the signal processed by wireless reception to the FFT / CP unit 67.

The FFT / CP unit 67 performs FFT processing on the signal output from the radio unit 66 to remove the CP. The FFT / CP unit 67 performs FFT processing and outputs a signal from which the CP has been removed to the digital BF unit 68.

The digital BF unit 68 multiplies the signal output from the FFT / CP unit 68 by the BF weight corresponding to the beam identification information 51b (BFI) fed back from the user terminals 4a to 4c. The digital BF unit 68 outputs a signal multiplied by the BF weight to the transmission unit 69.

The transmission unit 69 electrically-optically converts the signal output from the digital BF unit 68 and transmits it to the CU 1 via the FHM2.

The acquisition of the beam identification information 51b of DU3a to 3c will be described.

FIG. 7 is a diagram illustrating acquisition of beam identification information 51b of DU3a to 3c. FIG. 7 shows FHM2 and DU3a to 3b shown in FIG. Further, FIG. 7 shows the beam information 51 shown in FIG.

The beam information 51 is transmitted from the CU 1 (not shown in FIG. 7) to the FHM 2 as shown by the arrow A1 in FIG. Then, the beam information 51 is copied by FHM2 and transmitted to DU3a to 3c as shown by the arrow A2 in FIG.

The DUs 3a to 3c store the DU identification information assigned to the own machine in a storage unit (not shown in FIG. 6) provided by the DUs 3a to 3c. For example, the DU3a stores the DU identification information "DU # 1" of its own machine in the storage unit. The DU3b stores the DU identification information "DU # 2" of its own machine in the storage unit. The DU3c stores the DU identification information "DU # n" of its own machine in the storage unit.

The DUs 3a to 3c refer to the beam information 51 received from the FHM2 based on the DU identification information of the own machine, and acquire the beam identification information corresponding to the DU identification information of the own machine.

For example, the beam information 52 shown in FIG. 7 shows a part of the beam information 51 received by the DU3a from the FHM2. Since the DU identification information of the DU3a is "DU # 1", the control unit 62 of the DU3a acquires the beam identification information "BFI1, BFI2, BIF3, BFI4" shown in the thick frame of the beam information 52.

Further, for example, the beam information 53 shown in FIG. 7 shows a part of the beam information 51 received by the DU3b from the FHM2. Since the DU identification information of the DU3b is "DU # 2", the DU3b acquires the beam identification information "BFI5, BFI6, BIF7, BFI8" shown in the thick frame of the beam information 53.

Further, for example, the beam information 54 shown in FIG. 7 shows a part of the beam information 51 received by the DU3c from the FHM2. Since the DU identification information of the DU3c is "DU # n", the DU3c acquires the beam identification information "BFIm-3, BFIm-2, BIFm-1, BFIm" shown in the thick frame of the beam information 54. In this way, the DUs 3a to 3b acquire the unique beam identification information assigned to the own machine. The DUs 3a to 3b store the beam information 51 transmitted from the CU 1 in a storage unit (not shown in FIG. 6).

The DUs 3a to 3c sweep the beams in various directions in order to search for the optimum beam directed to the user terminals 4a to 4c. At this time, the DUs 3a to 3c include the beam identification information assigned to the own machine acquired from the beam information 51 in the beam to be swept.

FIG. 8 is a diagram illustrating the sweeping of the beam. In FIG. 8, the same components as those in FIG. 1 are designated by the same reference numerals.

The DUs 3a to 3c form beams in various directions as shown in FIG. 8 when searching for an optimum beam directed to the user terminals 4a to 4c. For example, the beams 71a to 71d shown in FIG. 8 indicate the beams formed by the DU3a. The beams 72a to 72d indicate the beams formed by the DU3b. The beams 73a to 73d indicate the beams formed by the DU3c.

When the beam is swept, the DUs 3a to 3c include the beam identification information assigned to the own machine in the beam.

For example, the beam identification information "BFI1, BFI2, BIF3, BFI4" is assigned to the DU3a. Therefore, the control unit 62 of the DU3a includes "BFI1, BFI2, BIF3, BFI4" in each of the sweeping beams 71a to 71d. For example, DU3a multiplies each of "BFI1, BFI2, BIF3, BFI4" by each of the BF weights forming the beams 71a to 71d.

Further, for example, the beam identification information "BFI5, BFI6, BIF7, BFI8" is assigned to the DU3b. Therefore, the DU3b includes "BFI5, BFI6, BIF7, BFI8" in each of the sweeping beams 72a to 72d. For example, DU3b multiplies each of "BFI5, BFI6, BIF7, BFI8" by each of the BF weights forming the beams 71a to 71d.

Further, for example, the beam identification information "BFIm-3, BFIm-2, BIFm-1, BFIm" is assigned to the DU3c. Therefore, the DU3c includes "BFIm-3, BFIm-2, BIFm-1, BFIm" in each of the sweeping beams 73a to 73d. For example, DU3b multiplies each of "BFIm-3, BFIm-2, BIFm-1, BFIm" by each of the BF weights forming the beams 71a to 71d. In this way, the DUs 3a-3c sweep the beam containing the beam identification information.

The user terminals 4a to 4c receive the swept beam output from the DUs 3a to 3c. The user terminals 4a to 4c feed back the beam identification information (BFI) of the beam having the best communication quality from the received beams to the CU1.

FIG. 9 is a diagram illustrating feedback of beam identification information. In FIG. 9, the same ones as those in FIG. 8 are designated by the same reference numerals.

The user terminal 4a receives the swept beam output from the DU 3a. It is assumed that the user terminal 4a has the best reception level of the beam of the beam identification information "BFI2" among the received beams. In this case, the user terminal 4a feeds back the beam identification information "BFI2" to the CU1 via the DU3a and the FHM2 as shown by the arrow A11 in FIG. More specifically, the user terminal 4a wirelessly transmits the beam identification information "BFI2" to the DU3a. The radio unit 66 of the DU 3a receives the beam identification information “BFI2” wirelessly transmitted from the user terminal 4a. The transmission unit 69 of the DU3a transmits the received beam identification information “BFI2” to the FHM2. The FHM2 transmits the beam identification information “BFI2” received from the DU3a to the CU1.

Similarly, the user terminal 4b receives the swept beam output from the DU 3b. It is assumed that the user terminal 4b has the best reception level of the beam of the beam identification information "BFI7" among the received beams. In this case, the user terminal 4a feeds back the beam identification information "BFI7" to the CU1 via the DU3b and the FHM2 as shown by the arrow A12 in FIG.

Similarly, the user terminal 4c receives the swept beam output from the DU 3c. It is assumed that the user terminal 4c has the best reception level of the beam of the beam identification information "BFIm-2" among the received beams. In this case, the user terminal 4a feeds back the beam identification information "BFIm-2" to the CU1 via the DU3c and the FHM2 as shown by the arrow A13 in FIG. In this way, the user terminals 4a to 4b feed back the beam identification information to the CU 1.

The sweep timing of the beams of DU3a to DU3c will be described.

FIG. 10 is a diagram illustrating an example of beam sweep timing. DU3a to DU3c sweep the beams so that the timings of sweeping the beams do not overlap with each other.

For example, the transmission timing 81 shown in FIG. 10 indicates the timing at which the DU3a sweeps the beam. The transmission timing 82 indicates the timing at which the DU 3b sweeps the beam. The transmission timing 83 indicates the timing at which the DU 3c sweeps the beam.

The DU3a outputs a beam including the beam identification information "BFI1" at the beam sweep timing 81a shown in the transmission timing 81. Further, the DU3a outputs a beam including the beam identification information "BFI2" at the beam sweep timing 81b shown in the transmission timing 81. Further, the DU3a outputs a beam including the beam identification information "BFI3" at the beam sweep timing 81c shown in the transmission timing 81. Further, the DU3a outputs a beam including the beam identification information "BFI4" at the beam sweep timing 81d shown in the transmission timing 81.

Similarly, the DU3b outputs a beam including the beam identification information “BFI5, BFI6, BFI7, BFI8” at each of the beam sweep timings 82a to 82d shown in the transmission timing 82.

Similarly, the DU3c outputs a beam including the beam identification information "BFIm-3, BFIm-2, BFIm-1, BFIm" at each of the beam sweep timings 83a to 83d shown in the transmission timing 83. In this way, the DUs 3a-3c sweep the beam.

As described with reference to FIG. 9, the user terminals 4a to 4c feed back the beam identification information to the CU 1. The user terminals 4a to 4c feed back the beam identification information to the CU 1 at a timing different from the transmission timings 81 to 83 shown in FIG. For example, when DU3a-3c sweep the beams, the sweep timing of each beam is different for each BFI. Therefore, the user terminals 4a to 4c can feed back the BFI with good communication quality depending on the timing of accessing (for example, random access) the DU3a to 3c (CU1) when the DU3a to 3c sweep the beam.

Further, the beam information 51 stored in the storage unit 32 is transmitted to the DUs 3a to 3c, for example, when the DUs 3a to 3c sweep the beam. For example, the beam information 51 is transmitted at the beam sweep timings 81a, 82a, 83a shown in FIG.

Data transmission (transmission of DL data signal) from CU1 to user terminals 4a to 4c will be described. When the CU 1 transmits data to the user terminals 4a to 4c existing under the DU 3a to 3c, the transmitted data includes the beam identification information fed back from the user terminals 4a to 4c. As shown in FIG. 5, the beam identification information is uniquely assigned over DU3a to 3c, so that the DU3a to 3c under FHM2 individually perform beamforming and transmit the data to the user terminals 4a to 4c. can do.

FIG. 11 is a diagram illustrating an example of data transmission to user terminals 4a to 4c. In FIG. 11, the same ones as those in FIG. 1 are designated by the same reference numerals.

When transmitting data to the user terminals 4a to 4c, the control unit 31 of the CU 1 includes the beam identification information fed back from the user terminals 4a to 4c in the data header and transmits the data to the FHM2.

For example, the beam identification information fed back from the user terminal 4a to the CU1 is referred to as "BFI2". The beam identification information fed back from the user terminal 4b to the CU1 is referred to as "BFI7". The beam identification information fed back from the user terminal 4c to the CU1 is referred to as "BFIm-2". In this case, the control unit 31 of the CU 1 includes the beam identification information "BFI2" in the header of the data to be transmitted to the user terminal 4a and transmits the beam identification information "BFI2" to the FHM2. Further, the control unit 31 of the CU 1 includes the beam identification information "BFI7" in the header of the data to be transmitted to the user terminal 4b and transmits the beam identification information "BFI7" to the FHM2. Further, the control unit 31 of the CU 1 includes the beam identification information "BFIm-2" in the header of the data to be transmitted to the user terminal 4c and transmits the beam identification information "BFIm-2" to the FHM2.

The data transmitted to FHM2 is copied by FHM2 and transmitted to DU3a to 3c. Since the DUs 3a to 3c receive (store) the beam information 51 transmitted from the CU 1, if the header of the received data includes the beam identification information 51b assigned to the own machine, the beam identification information 51b is included. A beam corresponding to the information 51b can be formed and data can be transmitted to the user terminals 4a to 4c.

For example, the DU3a can form a beam from the data identification information "BFI2" included in the data header in the direction corresponding to the "BFI2", and can transmit the data to the user terminal 4a. Further, the DU3b can form a beam from the data identification information "BFI7" included in the data header in the direction corresponding to the "BFI7", and can transmit the data to the user terminal 4b. Further, the DU 3c can form a beam from the data identification information "BFIm-2" included in the data header in the direction corresponding to the "BFIm-2", and can transmit the data to the user terminal 4c. As described above, the DUs 3a to 3c can individually control the beam direction by the unique beam identification information 51b associated with the DU identification information 51a.

As described above, the DUs 3a to 3c that perform wireless communication with the user terminals 4a to 4c and the CU 1 that communicates via the FHM 2 have a storage unit 32 that stores the beam information 51. The beam information 51 is information in which the DU identification information 51a of the DUs 3a to 3c and the beam identification information 51b assigned to each beam so as to be different between the beams formed by the DUs 3a to 3c are associated with each other. Further, the transmission unit 37 of the CU 1 transmits the beam information 51 stored in the storage unit 51 to the DU3a to 3c via the FHM2, and the reception unit 38 receives the beam information 51 from the user terminals 4a to 4c by the DU3a to 3c. , The beam identification information 51b assigned to the beam having the best communication quality is received from DU3a to 3c via FHM2. As a result, the CU 1 can individually control the beam directions of the DUs 3a to 3c under the FHM2. Further, since the CU 1 can individually control the beam directions of the DUs 3a to 3c under the FHM2, it can be flexibly scheduled for the user terminals 4a to 4c existing under the respective DUs 3a to 3c.

Further, the receiving unit 61 of the DU3a (3b, 3c) that communicates with the CU1 via the FHM2 and wirelessly communicates with the user terminals 4a to 4c receives the beam information 51 from the CU1 via the FHM2. The control unit 62 of the DU 3a acquires the beam identification information 51b corresponding to the DU identification information of the own machine from the beam information received by the reception unit 61. Further, the control unit 62 sweeps the beam using each beam identified by the acquired beam identification information 51b, and transmits the beam identification information 51b to the user terminals 4a to 4c. Then, the radio unit 66 of the DU3a receives the beam identification information 51b assigned to the beam having the best communication quality from the user terminals 4a to 4c, and the transmission unit 69 receives the beam identification information 61b received by the radio unit 66. Is transmitted to CU1 via FHM2. As a result, the DUs 3a to 3c under FHM2 can individually control the beam direction.

In the above, the CU 1 is supposed to transmit the beam information 51 stored in the storage unit 32 to the DU3a to 3c when the DU3a to 3c sweep the beam, but the present invention is not limited to this. For example, the CU 1 may transmit the beam information 51 to the DUs 3a to 3c when the beam information 51 is stored in the storage unit 32 or when the beam information 51 stored in the storage unit 32 is updated. good. In this case, the DUs 3a to 3c store the beam information 51 transmitted from the CU 1 in a storage unit provided by the DUs 3a to 3c. Then, the DUs 3a to 3c acquire the beam identification information 51b assigned to the own machine in advance from the beam information 51 stored in the storage unit, and when the beam is swept, the beam identification information 51b acquired in advance is used as a beam. It may be included in.

[Second Embodiment]
In the second embodiment, the FHM utilizes beam information to sort UL signals and noise. For example, FHM synthesizes a signal sent from a DU that has a user terminal under its control, and sends a signal to the CU without synthesizing a signal (that is, noise) sent from a DU that does not have a user terminal under its control. do.

FIG. 12 is a diagram showing a block example of the FHM 90 according to the second embodiment. As shown in FIG. 12, the FHM 90 includes a receiving unit 91, 97, a control unit 92, a storage unit 93, a copy unit 94, a delay offset unit 95, 99, a transmitting unit 96, 102, and an IFFT unit 98. And an FFT unit 101. The FHM 90 is connected, for example, between the CU 1 shown in FIG. 1 and the DUs 3a to 3c.

The receiving unit 91 receives the optical signal transmitted from the CU 1, performs optical-electric conversion, and outputs the optical signal to the control unit 92 and the copy unit 94.

The control unit 92 stores the beam information received by the reception unit 91 (transmitted from the CU 1) in the storage unit 93. As will be described in detail below, the control unit 92 stores the UL beam identification information included in the scheduling information of the user terminals 4a to 4c received by the reception unit 91 (transmitted from the CU 1) in the storage unit 93. The DU identification information is acquired by referring to the stored beam information. Then, the control unit 92 determines which DU3a to 3c the user terminals 4a to 4c are under, based on the acquired DU identification information. Then, the control unit 92 synthesizes which UL signal transmitted from the DU3a to 3c to the synthesis unit 100 based on the determination result of which DU3a to 3c the user terminals 4a to 4c are under. Control.

The copy unit 94 copies the signal received by the reception unit 91. For example, the copy unit 94 copies the received signal for DU3a to 3c. The copy unit 94 outputs the copied signal to the delay offset unit 95.

The delay offset unit 95 adjusts the delay time of the signal copied by the copy unit 94. For example, DU3a to 3c have different distances from FHM2 and different signal delay times (arrival times) depending on the installation location. Therefore, the delay offset unit 95 adjusts the signal transmission timing so as to suppress the difference in the signal delay time. The delay offset unit 95 outputs a signal adjusted for the delay time to the transmission unit 96.

The transmission unit 96 electrically-optically converts a signal whose delay time has been adjusted by the delay offset unit 95, and transmits the signal to the DUs 3a to 3c.

The receiving unit 97 receives the optical signals transmitted from the DUs 3a to 3c, performs optical-electric conversion, and outputs the optical signals to the IFFT unit 98.

The IFFT unit 98 performs an IFFT process on the signal output from the receiving unit 97. The IFFT unit 98 outputs the signal subjected to the IFFT process to the delay offset unit 99.

The delay offset unit 99 adjusts the delay time of the signal output from the IFFT unit 98. For example, DU3a to 3c have different distances from FHM2 and different signal delay times depending on the installation location. Therefore, the delay offset unit 99 adjusts the signal reception timing so as to eliminate the difference in signal delay time. The delay offset unit 99 outputs a signal adjusted for the delay time to the synthesis unit 100.

The synthesizing unit 100 synthesizes the signals of DU3a to 3c whose delay time is adjusted by the delay offset unit 99. At this time, the synthesizing unit 100 determines the signal to be synthesized according to the control of the control unit 92. The synthesizing unit 100 outputs the synthesized signal to the FFT unit 101.

The FFT unit 101 performs FFT processing on the signal output from the synthesis unit 100. The FFT unit 101 outputs the FFT-processed signal to the transmission unit 102.

The transmission unit 102 electrically-optically converts the signal subjected to the FFT processing by the FFT unit 101 and transmits it to the CU 1.

FIG. 13 is a diagram illustrating an example of signal synthesis of FHM2. In FIG. 13, the same ones as those in FIG. 1 are designated by the same reference numerals.

In the example of FIG. 13, the DU3a receives the UL signal indicated by the arrow A21 and the noise indicated by the arrow A22 from the user terminal 4a. The DU 3b receives the UL signal indicated by the arrow A23 from the user terminal 4b. The DU3c receives the noise indicated by the arrow A24. The noise indicated by the arrow A24 is, for example, the thermal noise of DU3c. Alternatively, the noise indicated by the arrow A24 is, for example, the interference noise of the user terminal 4b.

The UL signal and noise received by the DU3a to DU3c are transmitted to the FHM2. FHM2 synthesizes UL signals and noise received from DU3a to DU3c and transmits them to CU1.

For example, the four arrows A31 shown between FHM2 and CU1 in FIG. 13 correspond to the arrows A21 to A24 shown below DU3a to 3c. As shown by the arrow A31, the FHM2 synthesizes the UL signal and the noise and transmits the UL signal to the CU1.

In the radio base station of FIG. 13, increasing DU3a to 3c may increase the noise of UL transmitted to CU1. Therefore, in the radio base station of FIG. 13, if DU3a to 3c are increased, the UL area may be degenerated.

FIG. 14 is a diagram illustrating an example of signal synthesis of the FHM 90. In FIG. 14, the same ones as in FIG. 13 are designated by the same reference numerals. In FIG. 14, the FHM 90 described with reference to FIG. 12 is connected between the CU 1 and the DUs 3a to 3c with respect to FIG.

The FHM 90 synthesizes signals transmitted from DU3a and 3b having user terminals 4a and 4b under its control, and does not synthesize signals transmitted from DU3c having no user terminal under its control. For example, the FHM 90 receives from the user terminal 4a signals (UL signal indicated by the arrow A21 and noise indicated by the arrow A22) received from the DU3a and from the DU3b, as shown by the three arrows A41 between the FHM90 and the CU1. The signal of the user terminal 4b (the UL signal indicated by the arrow A23) is combined, and the signal received from the DU3c that does not exist under the user terminal (the noise indicated by the arrow A24) is not combined.

The above operation will be specifically described. The receiving unit 91 of the FHM 90 receives the beam information 51 transmitted from the CU 1 to the DUs 3a to 3c. The control unit 92 stores the beam information 51 received by the reception unit 91 in the storage unit 93.

Further, the receiving unit 91 of the FHM 90 receives the scheduling information transmitted from the CU 1 to the user terminals 4a and 4b. The scheduling information includes scheduling information of UL signals of user terminals 4a and 4b. The UL signal scheduling information includes beam identification information 51b when the user terminals 4a and 4b transmit the UL signal.

Beam information 51 is stored in the storage unit 93 of the FHM 90. Therefore, the control unit 92 of the FHM 90 refers to the beam identification information 51b of the beam information 51 stored in the storage unit 93 based on the beam identification information 51b included in the scheduling information of the UL signal. Whether or not the user terminals 4a and 4b exist in 3c can be specified.

For example, it is assumed that the beam information 51 shown in FIG. 5 is stored in the storage unit 93 of the FHM 90. Further, the beam identification information 51b included in the UL signal scheduling information is referred to as "BFI2, BFI7".

In this case, the control unit 92 refers to the beam information 51 (see FIG. 5) stored in the storage unit 93 based on the “BFI2, BFI7”, and the DU identification information “DU # 1” corresponding to the “BFI2”. And the DU identification information "DU # 2" corresponding to "BFI7". Thereby, the control unit 92 can identify that the user terminal exists under the control of the DU3a of the DU identification information "DU # 1" and the DU3b of the DU identification information "DU # 2".

The synthesis unit 100 of the FHM 90 synthesizes the signals sent from DU3a to DU3c. At this time, the control unit 92 synthesizes the signals sent from the DUs 3a and 3b that specify that the user terminal exists under the control, and does not synthesize the signals sent from the DU3c that specifies that the user terminal does not exist under the control. As described above, the synthesis unit 100 is controlled. As a result, even if the FHM 90 receives a signal (noise) from the DU3c, for example, the FHM90 does not synthesize the signal of the DU3c and transmit it to the CU1.

The CU 1 can be scheduled for each frequency with respect to the user terminals 4a and 4b. Since the FHM 90 selects the signal of the user terminal scheduled for each frequency, the noise on the signal of the other user terminal is not added.

As described above, the receiving unit 91 of the FHM2 that relays the communication between the CU1 and the DU3a to 3c receives the beam information 51 from the CU1. Further, the receiving unit 91 receives the scheduling information of the user terminals 4a to 4c that wirelessly communicate with the DUs 3a to 3c from the CU1. The control unit 92 acquires the DU identification information 51a corresponding to the UL beam identification information 51b included in the scheduling information from the beam information 51 received by the reception unit 91, and the user terminal 4a is obtained from the acquired DU identification information 51a. DU3a to 3c having ~ 4c under their control are specified. Then, the synthesis unit 100 synthesizes the UL signals transmitted from the specified DUs 3a to 3c, and the transmission unit 102 transmits the UL signals synthesized by the synthesis unit 100 to the CU1. As a result, the FHM 90 can reduce the noise of the UL signal transmitted to the CU 1. Further, FHM90 can suppress the degeneracy of the UL area even when DU3a to 3c are increased.

The embodiments have been described above. The FHMs 2 and 90 described in the above embodiment may have a switch function for the DL signal. For example, the FHMs 2 and 90 may switch the DL signal and transmit it to a predetermined DU3a to 3c.

(Hardware configuration)
The block diagram used in the description of the above embodiment shows a block of functional units. These functional blocks (components) are realized by any combination of hardware and / or software. Further, the means for realizing each functional block is not particularly limited. That is, each functional block may be realized by one physically and / or logically coupled device, or directly and / or indirectly by two or more physically and / or logically separated devices. (For example, wired and / or wireless) may be connected and realized by these plurality of devices.

For example, the radio base station (CU, FHM, DU) and the user terminal in one embodiment of the present invention may function as a computer that performs the processing of the present invention. FIG. 15 is a diagram showing an example of a hardware configuration of a radio base station and a user terminal according to an embodiment of the present invention. The above-mentioned radio base station and user terminal may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.

In the following description, the word "device" can be read as a circuit, a device, a unit, or the like. The hardware configuration of the radio base station and the user terminal may be configured to include one or more of the devices shown in the figure, or may be configured not to include some of the devices.

For example, although only one processor 1001 is shown, there may be a plurality of processors. Further, the processing may be executed by one processor, or the processing may be executed simultaneously, sequentially, or by other methods on one or more processors. The processor 1001 may be mounted on one or more chips.

For each function in the radio base station and the user terminal, by loading predetermined software (program) on the hardware such as the processor 1001 and the memory 1002, the processor 1001 performs an calculation, and the communication device 1004 communicates or the memory. It is realized by controlling the reading and / or writing of data in the 1002 and the storage 1003.

Processor 1001 operates, for example, an operating system to control the entire computer. The processor 1001 may be composed of a central processing unit (CPU) including an interface with a peripheral device, a control device, an arithmetic unit, a register, and the like. For example, it may be realized by the above-mentioned block example, processor 1001.

Further, the processor 1001 reads a program (program code), a software module or data from the storage 1003 and / or the communication device 1004 into the memory 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least a part of the operations described in the above-described embodiment is used. For example, at least a part of the functional blocks constituting the radio base station and the user terminal may be realized by a control program stored in the memory 1002 and operated by the processor 1001, and other functional blocks may be realized in the same manner. May be good. Although it has been described that the various processes described above are executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. Processor 1001 may be mounted on one or more chips. The program may be transmitted from the network via a telecommunication line.

The memory 1002 is a computer-readable recording medium, and is composed of at least one such as a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electrically Erasable Programmable ROM), and a RAM (Random Access Memory). May be done. The memory 1002 may be referred to as a register, a cache, a main memory (main storage device), or the like. The memory 1002 can store a program (program code), a software module, and the like that can be executed to implement the wireless communication method according to the embodiment of the present invention.

The storage 1003 is a computer-readable recording medium, for example, an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, an optical magnetic disk (for example, a compact disk, a digital versatile disk, a Blu-ray). It may consist of at least one (registered trademark) disk), smart card, flash memory (eg, card, stick, key drive), floppy (registered trademark) disk, magnetic strip, and the like. The storage 1003 may be referred to as an auxiliary storage device. The storage medium described above may be, for example, a database, server or other suitable medium containing memory 1002 and / or storage 1003.

The communication device 1004 is hardware (transmission / reception device) for communicating between computers via a wired and / or wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, or the like.

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives an input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may have an integrated configuration (for example, a touch panel).

Further, each device such as the processor 1001 and the memory 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be composed of a single bus or may be composed of different buses between the devices.

Further, the radio base station and the user terminal are hardware such as a microprocessor, a digital signal processor (DSP: Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array). It may be configured to include, and a part or all of each functional block may be realized by the hardware. For example, the processor 1001 may be implemented on at least one of these hardware.

(Information notification, signaling)
Further, the notification of information is not limited to the embodiment / embodiment described in the present specification, and may be performed by other methods. For example, information notification includes physical layer signaling (eg, DCI (Downlink Control Information), UCI (Uplink Control Information)), higher layer signaling (eg, RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, etc. It may be carried out by broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals, or a combination thereof. Further, the RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

(Adaptive system)
Each aspect / embodiment described herein includes LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G, 5G, FRA (Future Radio Access), W-CDMA. (Registered Trademarks), GSM (Registered Trademarks), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth It may be applied to (Registered Trademark), other systems that utilize appropriate systems and / or next-generation systems that are extended based on them.

(Processing procedure, etc.)
The processing procedures, sequences, flowcharts, and the like of each aspect / embodiment described in the present specification may be rearranged in order as long as there is no contradiction. For example, the methods described herein present elements of various steps in an exemplary order and are not limited to the particular order presented.

(Operation of base station)
In some cases, the specific operation performed by the base station (radio base station) in the present specification may be performed by its upper node. In a network consisting of one or more network nodes having a base station, various operations performed for communication with the terminal are performed on the base station and / or other network nodes other than the base station (eg, for example). It is clear that it can be done by MME (Mobility Management Entity), S-GW (Serving Gateway), etc., but not limited to these). Although the case where there is one network node other than the base station is illustrated above, it may be a combination of a plurality of other network nodes (for example, MME and S-GW).

(I / O direction)
Information, signals, etc. can be output from the upper layer (or lower layer) to the lower layer (or upper layer). Input / output may be performed via a plurality of network nodes.

(Handling of input / output information, etc.)
The input / output information and the like may be stored in a specific place (for example, a memory) or may be managed by a management table. Information to be input / output may be overwritten, updated, or added. The output information and the like may be deleted. The input information and the like may be transmitted to another device.

(Judgment method)
The determination may be made by a value represented by 1 bit (0 or 1), by a boolean value (Boolean: true or false), or by comparing numerical values (for example, a predetermined value). It may be done by comparison with the value).

(software)
Software, whether referred to as software, firmware, middleware, microcode, hardware description language, or other names, is an instruction, instruction set, code, code segment, program code, program, subprogram, software module. , Applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, features, etc. should be broadly interpreted.

Further, software, instructions, and the like may be transmitted and received via a transmission medium. For example, the software may use wired technology such as coaxial cable, fiber optic cable, twisted pair and digital subscriber line (DSL) and / or wireless technology such as infrared, wireless and microwave to website, server, or other. When transmitted from a remote source, these wired and / or wireless technologies are included within the definition of transmission medium.

(Information, signal)
The information, signals, etc. described herein may be represented using any of a variety of different techniques. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description are voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any of these. It may be represented by a combination of.

The terms described herein and / or the terms necessary for understanding the present specification may be replaced with terms having the same or similar meanings. For example, the channel and / or symbol may be a signal. Also, the signal may be a message. Further, the component carrier (CC) may be referred to as a carrier frequency, a cell, or the like.

("System", [Network])
The terms "system" and "network" used herein are used interchangeably.

(Parameters, channel names)
Further, the information, parameters, etc. described in the present specification may be represented by an absolute value, a relative value from a predetermined value, or another corresponding information. .. For example, the radio resource may be indexed.

The names used for the parameters described above are not limited in any way. Further, mathematical formulas and the like using these parameters may differ from those expressly disclosed herein. Since the various channels (eg, PUCCH, PDCCH, etc.) and information elements (eg, TPC, etc.) can be identified by any suitable name, the various names assigned to these various channels and information elements are in any respect. However, it is not limited.

(base station)
A base station (radio base station) can accommodate one or more (eg, three) cells (also referred to as sectors). When a base station accommodates multiple cells, the entire base station coverage area can be divided into multiple smaller areas, each smaller area being a base station subsystem (eg, a small indoor base station RRH: Remote). Communication services can also be provided by Radio Head). The term "cell" or "sector" refers to a portion or all of the coverage area of a base station and / or base station subsystem that provides communication services in this coverage. In addition, the terms "base station,""eNB,""cell," and "sector" may be used interchangeably herein. A base station may also be referred to by terms such as fixed station, NodeB, eNodeB (eNB), access point, femtocell, and small cell.

(Terminal)
User terminals may be mobile stations, subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals, mobiles, depending on the trader. It may also be referred to as a terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, UE (User Equipment), or some other suitable term.

(Meaning and interpretation of terms)
As used herein, the terms "determining" and "determining" may include a wide variety of actions. "Judgment" and "decision" are, for example, judgment, calculation, computing, processing, deriving, investigating, looking up (for example, table). , Searching in a database or another data structure), ascertaining can be considered as a "judgment" or "decision". Also, "judgment" and "decision" are receiving (for example, receiving information), transmitting (for example, transmitting information), input (input), output (output), and access. It may include (for example, accessing data in memory) to be regarded as "judgment" or "decision". In addition, "judgment" and "decision" are considered to be "judgment" and "decision" when the things such as solving, selecting, choosing, establishing, and comparing are regarded as "judgment" and "decision". Can include. That is, "judgment" and "decision" may include considering some action as "judgment" and "decision".

The terms "connected", "coupled", or any variation thereof, mean any direct or indirect connection or connection between two or more elements and each other. It can include the presence of one or more intermediate elements between two "connected" or "combined" elements. The connection or connection between the elements may be physical, logical, or a combination thereof. As used herein, the two elements are by using one or more wires, cables and / or printed electrical connections, and, as some non-limiting and non-comprehensive examples, radio frequencies. By using electromagnetic energies such as electromagnetic energies with wavelengths in the region, microwave region and light (both visible and invisible) regions, they can be considered to be "connected" or "coupled" to each other.

The reference signal may be abbreviated as RS (Reference Signal) and may be referred to as a pilot (Pilot) according to the applied standard. Further, the correction RS may be referred to as TRS (Tracking RS), PC-RS (Phase Compensation RS), PTRS (Phase Tracking RS), or Additional RS. Further, the demodulation RS and the correction RS may have different names corresponding to each. Further, the demodulation RS and the correction RS may be defined by the same name (for example, the demodulation RS).

The phrase "based on" as used herein does not mean "based on" unless otherwise stated. In other words, the statement "based on" means both "based only" and "at least based on".

The "part" in the configuration of each of the above devices may be replaced with a "means", a "circuit", a "device" and the like.

As long as "including", "comprising", and variations thereof are used herein or within the scope of the claims, these terms are as comprehensive as the term "comprising". Intended to be targeted. Moreover, the term "or" as used herein or in the claims is intended to be non-exclusive.

The radio frame may be composed of one or more frames in the time domain. Each one or more frames in the time domain may be referred to as a subframe, a time unit, or the like. Subframes may further consist of one or more slots in the time domain. The slot may be further composed of one or more symbols (OFDM (Orthogonal Frequency Division Multiplexing) symbol, SC-FDMA (Single Carrier-Frequency Division Multiple Access) symbol, etc.) in the time domain.

Radio frames, subframes, slots, and symbols all represent a unit of time in transmitting a signal. Radio frames, subframes, slots, and symbols may have different names for each.

For example, in an LTE system, a base station schedules each mobile station to allocate radio resources (frequency bandwidth that can be used in each mobile station, transmission power, etc.). The minimum time unit of scheduling may be called TTI (Transmission Time Interval).

For example, one subframe may be referred to as TTI, a plurality of consecutive subframes may be referred to as TTI, and one slot may be referred to as TTI.

A resource unit is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. Further, the time domain of the resource unit may include one or more symbols, and may have a length of one slot, one subframe, or one TTI. Each 1TTI and 1 subframe may be composed of one or a plurality of resource units. Further, the resource unit may be referred to as a resource block (RB: Resource Block), a physical resource block (PRB: Physical RB), a PRB pair, an RB pair, a scheduling unit, a frequency unit, or a subband. Further, the resource unit may be composed of one or a plurality of REs. For example, 1RE may be a resource smaller than the resource unit that is the resource allocation unit (for example, the smallest resource unit), and is not limited to the name RE.

The structure of the radio frame described above is merely an example, the number of subframes contained in the radio frame, the number of slots contained in the subframe, the number of symbols and resource blocks contained in the slots, and the subs contained in the resource block. The number of carriers can be varied.

Throughout this disclosure, if articles are added by translation, for example, a, an, and the in English, these articles are not explicitly indicated by the context to be otherwise. It shall include more than one.

(Variations of aspects, etc.)
Each aspect / embodiment described in the present specification may be used alone, in combination, or may be switched and used according to the execution. Further, the notification of predetermined information (for example, the notification of "being X") is not limited to the explicit one, but is performed implicitly (for example, the notification of the predetermined information is not performed). May be good.

Although the present invention has been described in detail above, it is clear to those skilled in the art that the present invention is not limited to the embodiments described in the present specification. The present invention can be implemented as modifications and modifications without departing from the spirit and scope of the present invention as determined by the description of the scope of claims. Therefore, the description of the present specification is for the purpose of exemplary explanation and does not have any limiting meaning to the present invention.

One aspect of the invention is useful for mobile communication systems.

1 CU
2,90 FHM
3a-3c DU
4a-4c User terminals 31,62,92 Control unit 32,93 Storage unit 33 I / F unit 34 Transmission signal generation unit 35 Coding modulation unit 36 Mapping unit 37, 69, 96, 102 Transmission unit 38, 61, 91, 97 Receiving unit 39 Demapping unit 40 Channel estimation unit 41 Demodulation / decoding unit 42 Communication quality acquisition unit 51 Beam information 51a DU identification information 51b Beam identification information 63,68 Digital BF unit 64 IFFT / CP unit 65,66 Radio unit 67 FFT / CP part 94 Copy part 95,99 Delay offset part 98 IFF part 100 Composite part 101 FFT part

Claims (8)

A signal processing device that communicates via a front-hole multiplexer and a plurality of wireless devices that perform wireless communication with a user terminal.
A storage unit that stores beam information associated with the device identification information of the plurality of wireless devices and the beam identification information assigned to each beam so as to be different between the beams formed by each wireless device.
A transmission unit that transmits the beam information to the plurality of wireless devices via the fronthaul multiplexer.
A receiving unit that receives the beam identification information assigned to the beam having the best communication quality received from the user terminal by the plurality of wireless devices from the plurality of wireless devices via the front hall multiplexer.
A signal processing device having. A control unit that includes the beam identification information received from the user terminal in the data when transmitting data to the user terminal.
The signal processing apparatus according to claim 1. A wireless device that communicates with a signal processing device via a fronthaul multiplexer and wirelessly communicates with a user terminal.
The beam information associated with the device identification information of the plurality of wireless devices and the beam identification information assigned to each beam so as to be different between the beams formed by each wireless device is transmitted to the beam information via the fronthaul multiplexer. The beam information receiver that receives from the signal processing device and
An acquisition unit that acquires the beam identification information corresponding to the device identification information of the own machine from the beam information, and
A sweeping unit that sweeps a beam using each beam identified by the acquired beam identification information and transmits the beam identification information to the user terminal.
A beam identification information receiving unit that receives the beam identification information assigned to the beam having the best communication quality from the user terminal.
A beam identification information transmitting unit that transmits the received beam identification information to the signal processing device via the fronthaul multiplexer, and a beam identification information transmitting unit.
Wireless device with. A receiving unit that receives data transmitted to the user terminal from the signal processing device via the fronthaul multiplexer.
A transmission unit that transmits the data to the user terminal by the beam identified by the beam identification information included in the data.
The wireless device according to claim 3, further comprising. A fronthaul multiplexer that relays communication between a signal processing device and multiple wireless devices.
The signal processing device receives the beam information associated with the device identification information of the plurality of wireless devices and the beam identification information assigned to each beam so as to be different between the beams formed by each wireless device. Beam information receiver and
A transmission unit that transmits the beam information to the plurality of wireless devices,
A scheduling information receiving unit that receives scheduling information of a user terminal that performs wireless communication with the plurality of wireless devices from the signal processing device.
From the beam information, the device identification information corresponding to the beam identification information of the uplink included in the scheduling information is acquired, and from the acquired device identification information, the wireless device having the user terminal under the control is specified. Department and
A synthesizer that synthesizes the uplink signal transmitted from the specified wireless device, and
A transmission unit that transmits the synthesized uplink signal to the signal processing device, and
Front hole multiplexer with. It is a beam control method of a plurality of wireless devices that perform wireless communication with a user terminal and a signal processing device that communicates via a fronthaul multiplexer.
The beam information associated with the device identification information of the plurality of wireless devices and the beam identification information assigned to each beam so as to be different between the beams formed by each wireless device is stored.
The beam information is transmitted to the plurality of radio devices via the fronthaul multiplexer, and the beam information is transmitted to the plurality of radio devices.
The beam identification information assigned to the beam having the best communication quality received from the user terminal by the plurality of wireless devices is received from the plurality of wireless devices via the front hall multiplexer.
Beam control method. A beam control method for a wireless device that communicates with a signal processing device via a fronthaul multiplexer and wirelessly communicates with a user terminal.
The beam information associated with the device identification information of the plurality of wireless devices and the beam identification information assigned to each beam so as to be different between the beams formed by each wireless device is transmitted to the beam information via the fronthaul multiplexer. Received from the signal processor
From the beam information, the beam identification information corresponding to the device identification information of the own machine is acquired, and the beam identification information is acquired.
The beam is swept using each beam identified by the acquired beam identification information, and the beam identification information is transmitted to the user terminal.
The beam identification information assigned to the beam having the best communication quality is received from the user terminal, and the beam identification information is received.
The received beam identification information is transmitted to the signal processing device via the fronthaul multiplexer.
Beam control method. It is a signal synthesis method of a fronthaul multiplexer that relays communication between a signal processing device and a plurality of wireless devices.
The signal processing device receives beam information associated with the device identification information of the plurality of wireless devices and the beam identification information assigned to each beam so as to be different between the beams formed by each wireless device. ,
The beam information is transmitted to the plurality of wireless devices, and the beam information is transmitted to the plurality of wireless devices.
Scheduling information of a user terminal that performs wireless communication with the plurality of wireless devices is received from the signal processing device.
From the beam information, the device identification information corresponding to the beam identification information of the uplink included in the scheduling information is acquired, and from the acquired device identification information, a wireless device having the user terminal under the control is specified.
The uplink signal transmitted from the specified wireless device is synthesized and combined.
The synthesized uplink signal is transmitted to the signal processing device.
Signal synthesis method.

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