JP6819192B2 - Wireless base stations, wireless communication terminals, wireless communication methods and programs - Google Patents

Description

The present invention relates to wireless base stations, wireless communication terminals, wireless communication methods and programs that perform wireless communication.

When wireless communication is performed between a wireless base station and a wireless communication terminal which is a mobile station, various wireless communication methods are used for communication between them. As one example, the TDD (Time Division Duplex) method is used. This TDD method is a method of switching between the transmission timing of the downlink frame transmitted by the wireless base station to the wireless communication terminal and the reception timing of the uplink frame received by the wireless base station from the wireless communication terminal for each time.

In such a TDD scheme, the subframes communicated between the user terminal and the radio base station are between the UL / DL configuration applied by the radio base station and the UL / DL configuration applied by another radio base station. A technique for classifying fixed subframes and dynamic subframes according to the relationship and applying different frequency allocation methods to each is disclosed (see, for example, Patent Document 1). Further, when communicating between a wireless base station and another wireless base station, it is often the case that the wireless base stations are connected by wire and communication is performed via the wired line. Further, in order to communicate between wireless communication terminals, it is performed via a higher-level communication network.

Japanese Unexamined Patent Publication No. 2014-175800

As described above, when communication is performed between wireless base stations using a wired line, a transmission delay for performing the protocol processing used in the communication occurs. In particular, when baseband information is transmitted and received between wireless base stations, it takes time to transmit and receive the information. Further, when a wireless communication terminal communicates with another wireless communication terminal via a higher-level communication network, it takes time for processing in the wireless base station and its higher-level network. Further, the technique described in Patent Document 1 relates to communication between a user terminal and a wireless base station, and does not relate to communication between wireless base stations or wireless communication terminals.

As described above, when a wireless base station or a wireless communication terminal communicates with another wireless base station or another wireless communication terminal, there is a problem that a considerable transmission delay occurs.

An object of the present invention is to provide a wireless base station, a wireless communication terminal, a wireless communication method and a program that solve the above-mentioned problems.

The radio base station of the present invention
A frame allocation unit that allocates inter-node link frames for communication with other radio base stations as part of the time-division multiplex frames that make up the transmitted and received radio signals.
The frequency for transmitting the inter-node link frame to the other radio base station is determined based on the orientation to the other radio base station to which the inter-node link frame is transmitted to the radio base station. Frequency determination part and
It has a communication unit that transmits a link frame between nodes assigned by the frame allocation unit using the frequency determined by the frequency determination unit at the frequency and the timing assigned to the radio base station.
Further, the wireless communication terminal of the present invention is
A frame allocation unit that allocates inter-node link frames for communication with other wireless communication terminals as part of the time-division multiplex frames that make up the transmitted and received wireless signals.
The frequency for transmitting the inter-node link frame to the other wireless communication terminal is determined based on the orientation of the inter-node link frame to the other wireless communication terminal to the wireless communication terminal. Frequency determination part and
It has a communication unit that transmits a link frame between nodes assigned by the frame allocation unit at a timing assigned to the frequency and the wireless communication terminal by using a frequency determined by the frequency determination unit.
Moreover, the wireless communication method of the present invention
It is a wireless communication method performed by a wireless base station.
The process of allocating inter-node link frames for communication with other wireless base stations to a part of the time-division multiplex frames that make up the transmitted and received wireless signals,
The frequency for transmitting the inter-node link frame to the other radio base station is determined based on the direction to the other radio base station to which the inter-node link frame is transmitted to the radio base station. Processing and
Using the determined frequency, the assigned inter-node link frame is transmitted at the frequency and the timing assigned to the radio base station.
In addition, it is a wireless communication method performed by a wireless communication terminal.
A process of allocating an inter-node link frame for communication with another wireless communication terminal to a part of the time-division multiplex frame constituting the transmitted / received wireless signal, and
The frequency for transmitting the inter-node link frame to the other wireless communication terminal is determined based on the direction to the other wireless communication terminal to which the inter-node link frame is transmitted to the wireless communication terminal. Processing and
Using the determined frequency, the assigned inter-node link frame is transmitted at the frequency and the timing assigned to the wireless communication terminal.
In addition, the program of the present invention
It is a program to be executed by a wireless base station.
A procedure for allocating inter-node link frames for communication with other radio base stations as part of the time-division multiplex frames that make up the transmitted and received radio signals, and
The frequency for transmitting the inter-node link frame to the other radio base station is determined based on the direction to the other radio base station to which the inter-node link frame is transmitted to the radio base station. Procedure and
Using the determined frequency, the procedure of transmitting the assigned inter-node link frame at the frequency and the timing assigned to the radio base station is executed.
In addition, it is a program to be executed by a wireless communication terminal.
A procedure for allocating inter-node link frames for communication with other wireless communication terminals as part of the time-division multiplex frames that make up the transmitted and received wireless signals, and
The frequency for transmitting the inter-node link frame to the other wireless communication terminal is determined based on the direction to the other wireless communication terminal to which the inter-node link frame is transmitted to the wireless communication terminal. Procedure and
Using the determined frequency, the procedure of transmitting the assigned inter-node link frame at the frequency and the timing assigned to the wireless communication terminal is executed.

As described above, in the present invention, communication with less transmission delay can be performed between wireless base stations or between wireless communication terminals.

It is a figure which shows an example of the general time division multiplex frame used in the TDD system. It is a figure which shows the 1st Embodiment of the radio base station of this invention. It is a flowchart for demonstrating an example of the wireless communication method in the wireless base station shown in FIG. It is a figure which shows the 2nd Embodiment of the radio base station of this invention. It is a figure which shows an example of the time division multiplex frame which the frame allocation part shown in FIG. 4 allocated the inter-node link frame. It is a figure which shows an example of the orientation of the cell formed by the radio base station shown in FIG. It is a figure which shows an example of the subcarrier set in each direction shown in FIG. It is a figure which shows an example of the adjacency state of a cell. It is a figure which shows an example of the allocation of a subframe. It is a figure which shows another example of the orientation of the cell formed by the radio base station shown in FIG. It is a figure which shows an example of the subcarrier set in each direction shown in FIG. It is a figure which shows another example of the adjacency state of a cell. It is a figure which shows another example of the allocation of a subframe. It is a flowchart for demonstrating an example of the wireless communication method in the wireless base station shown in FIG. It is a figure which shows the 1st Embodiment of the wireless communication terminal of this invention. It is a flowchart for demonstrating an example of the wireless communication method in the wireless communication terminal shown in FIG. It is a figure which shows the 2nd Embodiment of the wireless communication terminal of this invention. It is a figure which shows an example of the time division multiplex frame which the frame allocation part shown in FIG. 17 allocated the inter-node link frame. It is a flowchart for demonstrating an example of the wireless communication method in the wireless communication terminal shown in FIG. It is a figure which shows an example of the form in which a plurality of wireless communication terminals exist within the range of the cell covered by a wireless base station.

In recent years, LTE (Long Term Evolution) has become the mainstream as a wireless communication method used in cellular systems, and allocation of a wide frequency band has also become widespread. Further, in a wide frequency band, the TDD (Time Division Duplex) method is often applied. In the TDD system, the downlink and the uplink communicate with each other using the same frequency, and the downlink and the uplink divide the frames in a time division manner to realize the upper and lower communication.

FIG. 1 is a diagram showing an example of a general time division multiplex frame used in the TDD system. As shown in FIG. 1, a downlink frame and an uplink frame are assigned in a time division manner. The downlink frame is a frame for transmission to a wireless communication terminal which is a mobile station in a wireless base station, and a frame for reception from a wireless base station in a wireless communication terminal. In the uplink frame, the wireless base station serves as a frame for receiving from the wireless communication terminal, and the wireless communication terminal serves as a frame for transmitting to the wireless base station.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First Embodiment of Radio Base Station)

FIG. 2 is a diagram showing a first embodiment of the radio base station of the present invention. As shown in FIG. 2, the radio base station 100 in the present embodiment has a frame allocation unit 110, a frequency determination unit 120, and a communication unit 130. Note that FIG. 2 shows an example of the main components related to the present embodiment among the components provided in the radio base station 100 in the present embodiment. Further, the radio base station 100 uses the TDD method to perform wireless communication with other radio base stations and wireless communication terminals.

The frame allocation unit 110 allocates an inter-node link frame for communicating with another radio base station to a part of the time-division multiplex frame constituting the transmitted / received radio signal. The frequency determination unit 120 determines the frequency for transmitting the inter-node link frame to the other radio base station based on the orientation of the radio base station 100 to the other radio base station to which the inter-node link frame is transmitted. decide. The communication unit 130 communicates with another radio base station by using the inter-node link frame assigned by the frame allocation unit 110. Specifically, the communication unit 130 transmits the inter-node link frame assigned by the frame allocation unit 110 at the frequency and the timing assigned to the radio base station 100 by using the frequency determined by the frequency determination unit 120.

The wireless communication method in the wireless base station 100 shown in FIG. 2 will be described below. FIG. 3 is a flowchart for explaining an example of a wireless communication method in the wireless base station 100 shown in FIG.

First, the frame allocation unit 110 allocates an inter-node link frame for communicating with another radio base station to a part of the time-division multiplex frame constituting the transmitted / received radio signal (step S1). Subsequently, the frequency determination unit 120 transmits the inter-node link frame to the other radio base station based on the orientation of the radio base station 100 to the other radio base station to which the inter-node link frame is transmitted. The frequency of (step S2) is determined. Then, the communication unit 130 transmits the inter-node link frame assigned by the frame allocation unit 110 at the timing assigned to the frequency and the radio base station 100 using the frequency determined by the frequency determination unit 120 (step S3). ..

In this way, the radio base station allocates a frame for communicating with another radio base station to a part of the time-division multiplex frame constituting the radio signal to be transmitted and received, and serves as a transmission destination of the frame. The frame is transmitted at a predetermined timing using a frequency based on the orientation of the radio base station. Therefore, communication with less transmission delay can be performed between wireless base stations.
(Second Embodiment of Radio Base Station)

FIG. 4 is a diagram showing a second embodiment of the radio base station of the present invention. As shown in FIG. 4, the radio base station 101 in the present embodiment has a frame allocation unit 111, a frequency determination unit 121, a communication unit 131, and a storage unit 141. Note that FIG. 4 shows an example of the main components related to the present embodiment among the components provided in the radio base station 101 in the present embodiment. Further, the radio base station 101 uses the TDD method to perform wireless communication with other radio base stations and wireless communication terminals.

The frame allocation unit 111 allocates an inter-node link frame for communicating with another radio base station to a part of the time-division multiplex frame constituting the transmitted / received radio signal. At this time, the frame allocation unit 111 allocates the inter-node link frame between the downlink frame and the uplink frame among the time division multiplexing frames.

FIG. 5 is a diagram showing an example of a time division multiplexing frame in which the frame allocation unit 111 shown in FIG. 4 allocates a link frame between nodes. As shown in FIG. 5, the frame allocation unit 111 shown in FIG. 4 is used to receive a downlink frame for transmitting a wireless signal to a wireless communication terminal among time-division multiplex frames and a wireless signal from the wireless communication terminal. The inter-node link frame 300-1 is assigned (added) between the uplink frame and the uplink frame.

Further, the frame allocation unit 111 uses an inter-node link frame (first inter-node link frame) for transmitting a signal from the radio base station 101 to another radio base station as an inter-node link frame, and another radio base. An inter-node link frame (second inter-node link frame) for receiving the signal transmitted from the station at the radio base station 101 is assigned.

The storage unit 141 stores the orientation and the frequency in advance in association with each other. This "direction" is the direction of another radio base station from the radio base station 101. Further, the "frequency" is a frequency of a subcarrier used for transmitting and receiving a link frame between nodes between radio base stations.

The frequency determination unit 121 reads from the storage unit 141 the frequency associated with the direction to another radio base station that is the transmission destination of the inter-node link frame. The frequency determination unit 121 determines the frequency read from the storage unit 141 as the frequency for transmitting the inter-node link frame to another radio base station.

The communication unit 131 transmits the inter-node link frame assigned by the frame allocation unit 111 at the timing assigned to the frequency and the radio base station 101 by using the frequency determined by the frequency determination unit 121.

FIG. 6 is a diagram showing an example of the orientation of the cell formed by the radio base station 101 shown in FIG. In the example shown in FIG. 6, there are six cells adjacent to the cells formed by the radio base station 101 shown in FIG. As shown in FIG. 6, the orientation around the cell formed by the radio base station 101 is divided into six, and each orientation is defined as 1 to 6. For example, the direction in which the radio base station 501 is arranged is "direction 1". The direction in which the radio base station 502 is arranged is "direction 2". The direction in which the radio base station 503 is arranged is "direction 3". The direction in which the radio base station 504 is arranged is "direction 4". The direction in which the radio base station 505 is arranged is "direction 5". The direction in which the radio base station 506 is arranged is "direction 6".

FIG. 7 is a diagram showing an example of subcarriers set in each orientation shown in FIG. As shown in FIG. 7, the transmission of the subcarrier f1 is assigned to the direction 1 shown in FIG. Further, the reception of the subcarrier f3 is assigned to the direction 2 shown in FIG. Further, the transmission of the subcarrier f2 is assigned to the direction 3 shown in FIG. Further, the reception of the subcarrier f1 is assigned to the direction 4 shown in FIG. Further, the transmission of the subcarrier f3 is assigned to the direction 5 shown in FIG. Further, reception of the subcarrier f2 is assigned to the direction 6 shown in FIG. Further, any of the three timings A to C is set in each cell. The timings A to C are timings used by the radio base stations forming the respective cells to transmit and receive subframes used for inter-node communication with other radio base stations. Timings A to C can be set and changed arbitrarily.

FIG. 8 is a diagram showing an example of the adjacent state of cells. As shown in FIG. 8, cells A to F are adjacent to cell G. Any of timings A to C is set in each of cells A to G.

FIG. 9 is a diagram showing an example of subframe allocation. In FIG. 9, the radio base stations forming each of the cells A to G shown in FIG. 8 are referred to as base stations A to G. The base station G for which the timing A is set transmits the inter-node link frame using the subframe a and receives the link frame using the subframe c. The base stations A, C, and E for which the timing B is set transmit the inter-node link frame using the subframe b and receive the internode link frame using the subframe a. The base stations B, D, and F for which the timing C is set transmit the inter-node link frame using the subframe c and receive it using the subframe b. Further, in the frame used for inter-node link communication, three subcarriers having transmission frequencies f1, f2, and f3 are prepared and applied to transmission / reception of communication in different directions.

As shown in FIG. 9, in the inter-node link communication from the base station G to the base station A, the subcarrier of the frequency f1 is used, the subframe a is transmitted at the timing A, and the subframe a is received at the timing B. (G1). Further, in the inter-node link communication from the base station G to the base station C, the subcarrier of the frequency f2 is used, the subframe a is transmitted at the timing A, and the subframe a is received at the timing B. Further, in the inter-node link communication from the base station G to the base station E, the subcarrier of the frequency f3 is used, the subframe a is transmitted at the timing A, and the subframe a is received at the timing B. Further, in the inter-node link communication from the base station A to the base station B, the subcarrier of the frequency f2 is used, the subframe b is transmitted at the timing B, and the subframe b is received at the timing C (a3). Further, in the inter-node link communication from the base station E to the base station D, the subcarrier of the frequency f2 is used, the subframe b is transmitted at the timing B, and the subframe b is received at the timing C. Further, in the inter-node link communication from the base station A to the base station F, the subcarrier of the frequency f3 is used, the subframe b is transmitted at the timing B, and the subframe b is received at the timing C. Further, in the inter-node link communication from the base station C to the base station B, the subcarrier of the frequency f1 is used, the subframe b is transmitted at the timing B, and the subframe b is received at the timing C. Further, in the inter-node link communication from the base station C to the base station D, the subcarrier of the frequency f3 is used, the subframe b is transmitted at the timing B, and the subframe b is received at the timing C. Further, in the inter-node link communication from the base station E to the base station F, the subcarrier of the frequency f1 is used, the subframe b is transmitted at the timing B, and the subframe b is received at the timing C. Further, in the inter-node link communication from the base station D to the base station G, the subcarrier of the frequency f1 is used, the subframe c is transmitted at the timing C, and the subframe c is received at the timing A. Further, in the inter-node link communication from the base station F to the base station G, the subcarrier of the frequency f2 is used, the subframe c is transmitted at the timing C, and the subframe c is received at the timing A. Further, in the inter-node link communication from the base station B to the base station G, the subcarrier of the frequency f3 is used, the subframe c is transmitted at the timing C, and the subframe c is received at the timing A (c5).

In this way, the orientation, transmission / reception, and subcarriers are associated with each other so as to be different between adjacent cells. That is, in cells adjacent to each other, the subframe and transmission / reception timings are set so as not to be the same.

Below, regarding the specific operation of inter-node link communication between radio base stations, communication is performed between the base station G installed in the cell G and the base station B installed in the cell B shown in FIG. The case of doing this will be described as an example. First, the operation when the subframe is transmitted from the base station G to the base station B will be described.
Since the transmission / reception direction is set according to the direction as described above, when the subframe is transmitted from the base station G to the base station B, the subframe is transmitted from the base station G to the base station B arranged in the reception direction. It cannot be sent directly. Therefore, the base station G transmits a subframe via the base station A (relay radio base station) arranged in the transmission direction. That is, the transmission route of the subframe is cell G (transmitted from direction 1) → cell A (received in direction 4 / transmitted from direction 3) → cell B (received in cell 6). Further, since the subcarrier is also set in advance, the subframe is transmitted from the cell G (direction 1, subcarrier f1) to the cell A using the subframe a, and is transmitted from the cell A (direction 3, subcarrier f2) to the cell. It is sent to B.
Next, the operation when the subframe is transmitted from the base station B to the base station G will be described. Similarly, it follows the transmission / reception direction set according to the orientation. When a subframe is transmitted from the base station B to the base station G, since the base station G is arranged in the transmission direction from the base station B, the subframe can be directly transmitted. In this case, the transmission route of the subframe is cell B (transmitted from the direction 5) → cell G (received in cell 2). Further, since the subcarrier is also set in advance, the subframe is transmitted from the cell B (direction 5, subcarrier f3) to the cell G using the subframe c.
The method of communication with the adjacent cell is the same between other cells. Communication is performed via a communication path in the direction following the arrow shown in FIG.

As described above, the frequency arrangement is conscious by setting and fixing the direction of each cell (radio base station) from the cell (radio base station), transmission / reception, and frequency (subcarrier) in advance. It is easy to arrange the cells so that the timings a, b, and c of the adjacent cells are not the same (so that the cells of the same timing among the cells of the three types of timing shown in FIG. 7 are not adjacent to each other). Inter-communication is possible.

FIG. 10 is a diagram showing another example of the orientation of the cell formed by the radio base station 101 shown in FIG. In the example shown in FIG. 10, there are four cells adjacent to the cells formed by the radio base station 101 shown in FIG. As shown in FIG. 10, the orientation around the cell formed by the radio base station 101 is divided into four, and each orientation is defined as 1 to 4. For example, the direction in which the radio base station 511 is arranged is "direction 1". The direction in which the radio base station 512 is arranged is "direction 2". The direction in which the radio base station 513 is arranged is "direction 3". The direction in which the radio base station 514 is arranged is "direction 4".

FIG. 11 is a diagram showing an example of subcarriers set in each orientation shown in FIG. As shown in FIG. 11, the communication (transmission / reception) direction and the subcarriers (frequency: f1, f2) used for transmission / reception are set in advance for each direction of each cell. In addition, two types of timings A and B are set in advance as timings to be applied to transmission and reception of subframes used for inter-node communication. These timings can be set and changed arbitrarily. Further, the transmission and reception directions and the subcarrier are set in association with each other for each timing. For example, as shown in FIG. 11, in the cell set at the timing A, the direction 1 is the transmission of the subcarrier f1, the direction 2 is the reception of the subcarrier f2, the direction 3 is the transmission of the subcarrier f2, and the direction 4 is the subcarrier. It is set to apply only the reception of f1. Further, the cell set at the timing B applies only the reception of the subcarrier f2 in the direction 1, the transmission of the subcarrier f1 in the direction 2, the reception of the subcarrier f1 in the direction 3, and the transmission of the subcarrier f2 in the direction 4. Is set.

FIG. 12 is a diagram showing another example of the adjacent state of cells. As shown in FIG. 12, four cells A, C, E, and G are adjacent to cell I. Further, cell B is adjacent to cell A and cell C. Further, cell D is adjacent to cell C and cell E. Further, cell F is adjacent to cell E and cell G. Further, cell H is adjacent to cell G and cell A. Either timing A or B is set in each of cells A to I.

FIG. 13 is a diagram showing another example of subframe allocation. In FIG. 13, the radio base stations forming the cells A to C and I shown in FIG. 12 are referred to as base stations A to C and I. The base stations I and B for which the timing A is set transmit the inter-node link frame using the subframes a and c, and receive the inter-node link frame using the subframes b and d. Base stations A and C for which timing B is set transmit inter-node link frames using subframes b and d, and receive them using subframes a and c. Further, in the frame used for inter-node link communication, two subcarriers having transmission frequencies f1 and f2 are prepared and applied to transmission / reception of communication in different directions.

Below, regarding the specific operation of inter-node link communication between radio base stations, communication is performed between base station I installed in cell I and base station C installed in cell C shown in FIG. The case of doing this will be described as an example. First, the operation when the subframe is transmitted from the base station I to the base station C will be described.
Since the transmission / reception direction is set according to the direction as described above, when the frame is transmitted from the base station I to the base station C, the frame is directly transmitted from the base station I to the base station C arranged in the reception direction. Can't be done. Therefore, the base station I transmits a subframe via the base station A and the base station B (relay radio base station) arranged in the transmission direction. That is, the transmission path of the subframe is cell I (transmit from direction 1) → cell A (receive in direction 3 / transmit from direction 2) → cell B (receive in direction 4 / transmit from direction 3) → cell C ( (Received in cell 1). Further, since the subcarrier is also set in advance, the subframe is transmitted from the cell I (direction 1, subcarrier f1) to the cell A using the subframe a, and is transmitted from the cell A (direction 2, subcarrier f1) to the cell. It is transmitted to B, and is transmitted from cell B (direction 3, subcarrier f2) to cell C.
Next, the operation when the subframe is transmitted from the base station C to the base station I will be described. Similarly, it follows the transmission / reception direction set according to the orientation. When a subframe is transmitted from the base station C to the base station I, since the base station I is arranged in the transmission direction from the base station C, the subframe can be directly transmitted. In this case, the transmission path of the frame is cell C (transmitted from the direction 4) → cell I (received in the direction 2). Further, since the subcarrier is also set in advance, the subframe is transmitted from the cell C (direction 4, subcarrier f2) to the cell I using the subframe d.
The method of communication with the adjacent cell is the same between other cells. Communication is performed via a communication path in the direction following the arrow shown in FIG.

The wireless communication method in the wireless base station shown in FIG. 4 will be described below. FIG. 14 is a flowchart for explaining an example of the wireless communication method in the wireless base station 101 shown in FIG.

First, the frame allocation unit 111 allocates an inter-node link frame for communicating with another radio base station to a part of the time-division multiplex frame constituting the transmitted / received radio signal (step S11). At this time, the frame allocation unit 111 allocates the inter-node link frame between the downlink frame and the uplink frame among the time division multiplexing frames.
Subsequently, the frequency determination unit 121 determines whether or not the direction of the radio base station 101 to another radio base station to which the inter-node link frame is transmitted is the reception direction (step S12). This determination is made based on a preset correspondence between the orientation and the transmission / reception direction.

When the orientation of the radio base station 101 to another radio base station to which the internode link frame is transmitted is the reception orientation, the frequency determination unit 121 is a relay radio base which is a radio base station arranged in the transmission orientation. The frequency for transmitting the inter-node link frame to the station is determined (step S13). On the other hand, when the direction of the radio base station 101 to another radio base station to which the inter-node link frame is transmitted is not the reception direction, that is, the transmission direction, the frequency determination unit 121 sends the radio base station to the radio base station. The frequency for transmitting the inter-node link frame is determined (step S14). The frequencies determined in steps S13 and S14 are stored in the storage unit 141 in advance in association with the orientation, and the frequency determination unit 121 reads from the storage unit 141 and determines the frequencies based on the orientation.

After that, the communication unit 131 transmits the inter-node link frame assigned by the frame allocation unit 111 using the frequency determined by the frequency determination unit 121 at the timing assigned to the frequency and the radio base station 101 (step S15). .. Here, the transmission timings are, for example, timings A to C described with reference to FIGS. 7 to 9 and timings A and B described with reference to FIGS. 11 to 13.

In this way, the radio base station allocates a frame for communicating with another radio base station to a part of the time-division multiplex frame constituting the radio signal to be transmitted and received, and serves as a transmission destination of the frame. The frame is transmitted at a predetermined timing using a frequency based on the orientation of the radio base station. Therefore, in particular, it is possible to communicate between radio base stations for baseband information faster than using a wired line.
(First Embodiment of Wireless Communication Terminal)

FIG. 15 is a diagram showing a first embodiment of the wireless communication terminal of the present invention. As shown in FIG. 15, the wireless communication terminal 200 in this embodiment has a frame allocation unit 210, a frequency determination unit 220, and a communication unit 230. Note that FIG. 15 shows an example of the main components related to the present embodiment among the components provided in the wireless communication terminal 200 in the present embodiment. Further, the wireless communication terminal 200 uses the TDD method to perform wireless communication with other wireless communication terminals and wireless base stations.

The frame allocation unit 210 allocates an inter-node link frame for communicating with another wireless communication terminal to a part of the time-division multiplex frame constituting the transmitted / received wireless signal. The frequency determination unit 220 determines the frequency for transmitting the inter-node link frame to the other wireless communication terminal based on the orientation of the wireless communication terminal 200 to the other wireless communication terminal to which the inter-node link frame is transmitted. decide. The communication unit 230 communicates with another wireless communication terminal by using the inter-node link frame assigned by the frame allocation unit 210. Specifically, the communication unit 230 transmits the inter-node link frame assigned by the frame allocation unit 210 at the frequency and the timing assigned to the wireless communication terminal 200 by using the frequency determined by the frequency determination unit 220.

The wireless communication method in the wireless communication terminal 200 shown in FIG. 15 will be described below. FIG. 16 is a flowchart for explaining an example of a wireless communication method in the wireless communication terminal 200 shown in FIG.

First, the frame allocation unit 210 allocates an inter-node link frame for communicating with another wireless communication terminal to a part of the time-division multiplex frame constituting the transmitted / received wireless signal (step S21). Subsequently, the frequency determination unit 220 transmits the inter-node link frame to the other wireless communication terminal based on the orientation of the inter-node link frame to the other wireless communication terminal to the wireless communication terminal 200. The frequency of (step S22) is determined. Then, the communication unit 230 transmits the inter-node link frame assigned by the frame allocation unit 210 at the timing assigned to the frequency and the wireless communication terminal 200 using the frequency determined by the frequency determination unit 220 (step S23). ..

In this way, the wireless communication terminal allocates a frame for communicating with another wireless communication terminal to a part of the time-division multiplex frame constituting the transmitted / received wireless signal, and serves as a transmission destination of the frame. The frame is transmitted at a predetermined timing using a frequency based on the orientation of the wireless communication terminal. Therefore, communication with less transmission delay can be performed between the wireless communication terminals.
(Second Embodiment of Wireless Communication Terminal)

FIG. 17 is a diagram showing a second embodiment of the wireless communication terminal of the present invention. As shown in FIG. 17, the wireless communication terminal 201 in this embodiment has a frame allocation unit 211, a frequency determination unit 221, a communication unit 231 and a storage unit 241. Note that FIG. 17 shows an example of the main components related to the present embodiment among the components provided in the wireless communication terminal 201 in the present embodiment. Further, the wireless communication terminal 201 uses the TDD method to perform wireless communication with other wireless communication terminals and wireless base stations.

The frame allocation unit 211 allocates a node-to-node link frame for communicating with another wireless communication terminal to a part of the time division multiplexing frame constituting the transmitted / received wireless signal. At this time, the frame allocation unit 211 allocates the inter-node link frame between the downlink frame and the uplink frame among the time division multiplexing frames.

FIG. 18 is a diagram showing an example of a time division multiplexing frame in which the frame allocation unit 211 shown in FIG. 17 allocates a link frame between nodes. As shown in FIG. 18, the frame allocation unit 211 shown in FIG. 17 is used to transmit a downlink frame for receiving a radio signal from a radio base station among time-division multiplex frames and a radio signal to the radio base station. The inter-node link frame 400-1 is assigned (added) between the uplink frame and the uplink frame.

Further, the frame allocation unit 211 uses the inter-node link frame (first inter-node link frame) for transmitting a signal from the wireless communication terminal 201 to another wireless communication terminal as an inter-node link frame, and another wireless communication. An inter-node link frame (second inter-node link frame) for receiving the signal transmitted from the terminal at the wireless communication terminal 201 is assigned.

The storage unit 241 stores the orientation and the frequency in advance in association with each other. This "direction" is the direction of another wireless communication terminal from the wireless communication terminal 201. Further, the "frequency" is a frequency of a subcarrier used for transmitting and receiving a link frame between nodes between wireless communication terminals.

The frequency determination unit 221 reads from the storage unit 241 the frequency associated with the direction to another wireless communication terminal that is the transmission destination of the inter-node link frame. The frequency determination unit 221 determines the frequency read from the storage unit 241 as a frequency for transmitting the inter-node link frame to another wireless communication terminal.

The communication unit 231 transmits the inter-node link frame assigned by the frame allocation unit 211 using the frequency determined by the frequency determination unit 221 at the timing assigned to the frequency and the wireless communication terminal 201.

The correspondence between the preset orientation and the transmission / reception direction, the subcarrier (frequency) and subframe used for transmission, and the timing of transmitting the subframe are the same as those in the above-mentioned inter-node communication between radio base stations. Is.

The wireless communication method in the wireless communication terminal shown in FIG. 17 will be described below. FIG. 19 is a flowchart for explaining an example of a wireless communication method in the wireless communication terminal shown in FIG.

First, the frame allocation unit 211 allocates an inter-node link frame for communicating with another wireless communication terminal to a part of the time-division multiplex frame constituting the transmitted / received wireless signal (step S31). At this time, the frame allocation unit 211 allocates the inter-node link frame between the downlink frame and the uplink frame among the time division multiplexing frames.
Subsequently, the frequency determination unit 221 determines whether or not the direction of the wireless communication terminal 201 to another wireless communication terminal to which the inter-node link frame is transmitted is the reception direction (step S32). This determination is made based on a preset correspondence between the orientation and the transmission / reception direction.

When the direction of the wireless communication terminal 201 to another wireless communication terminal to which the inter-node link frame is transmitted is the reception direction, the frequency determination unit 221 relays wireless communication which is a wireless communication terminal arranged in the transmission direction. The frequency for transmitting the inter-node link frame to the terminal is determined (step S33). On the other hand, when the direction of the wireless communication terminal 201 to another wireless communication terminal to which the internode link frame is transmitted is not the reception direction, that is, the transmission direction, the frequency determination unit 221 moves to the wireless communication terminal. The frequency for transmitting the inter-node link frame is determined (step S34). The frequencies determined in steps S33 and S34 are stored in the storage unit 241 in advance in association with the orientation, and the frequency determination unit 221 reads out from the storage unit 241 based on the orientation and determines the frequency.

After that, the communication unit 231 transmits the inter-node link frame assigned by the frame allocation unit 211 using the frequency determined by the frequency determination unit 221 at the timing assigned to the frequency and the wireless communication terminal 201 (step S35). .. Here, the transmission timing is the same as, for example, the timings A to C described with reference to FIGS. 7 to 9 and the timings A and B described with reference to FIGS. 11 to 13 for the radio base station.

In this way, the wireless communication terminal allocates a frame for communicating with another wireless communication terminal to a part of the time-division multiplex frame constituting the transmitted / received wireless signal, and serves as a transmission destination of the frame. The frame is transmitted at a predetermined timing using a frequency based on the orientation of the wireless communication terminal. Therefore, it is possible to independently perform communication between mobile devices. In particular, it is possible to send information from the network side to mobile devices that are out of service area.

Similarly, a mode in which the present invention is applied between three or more wireless communication terminals will be described.

FIG. 20 is a diagram showing an example of a mode in which a plurality of wireless communication terminals exist within a cell covered by a wireless base station. As shown in FIG. 20, the radio base station 102 and the radio base station 103 perform inter-radio base station communication by using the above-described operation. Further, a plurality of wireless communication terminals 202 to 205 exist within the range of the cell covered by the wireless base station 102, and the wireless communication terminal 206 exists outside the range.

Regarding the communication between the radio base station 102 and the radio base station 103, the information used in the baseband processing can be transferred between the radio base stations because the communication can be performed without using the wired line by performing the above-mentioned operation. It is possible to send and receive quickly with. For example, by exchanging the transmission power control information and the transmission power value between radio base stations, it is possible to determine the optimum transmission power value. In addition, scheduling information for assigning a user (mobile station) to each frame can be exchanged between radio base stations, which can be used to avoid interference.

As shown in FIG. 20, the wireless communication terminal 202 performs wireless communication with the wireless communication terminal 203 and the wireless communication terminal 204. Further, the wireless communication terminal 205 communicates with the wireless communication terminal 206 existing outside the service area of the cell covered by the wireless base station 102.

Further, when the base station is arranged on an artificial satellite, information can be exchanged between the satellites without going through the ground station. Normally, even when monitoring and controlling a base station from a ground station, even if some kind of failure occurs, a communication method between satellites can be prepared, which is effective as a fail-safe.

The processing performed by each component provided in each of the above-mentioned wireless base stations 100, 101 and wireless communication terminals 200, 201 may be performed by logic circuits manufactured according to the purpose. Further, a computer program (hereinafter referred to as a program) in which the processing contents are described as a procedure is recorded on a recording medium readable by each of the wireless base stations 100, 101 and the wireless communication terminals 200, 201, and recorded on the recording medium. The program may be read and executed by the wireless base stations 100, 101 and the wireless communication terminals 200, 201, respectively. The recording media that can be read by the wireless base stations 100 and 101 and the wireless communication terminals 200 and 201 are floppy (registered trademark) disks, magneto-optical disks, DVDs (Digital Versailles Disc), and CDs (Compact Disc) Blu-ray. (Registered trademark) In addition to transferable recording media such as a disk, memory such as ROM (Read Only Memory) and RAM (Random Access Memory) built into each of the wireless base stations 100, 101 and wireless communication terminals 200, 201 Refers to HDD (Hard Disk Drive) and the like. The program recorded on this recording medium is read by a CPU (Central Processing Unit) provided in each of the wireless base stations 100, 101 and the wireless communication terminals 200, 201, and is the same as the one described above under the control of the CPU. Processing is done. Here, the CPU operates as a computer that executes a program read from a recording medium in which the program is recorded.

Some or all of the above embodiments may also be described, but not limited to:
(Appendix 1) A wireless base station
A frame allocation unit that allocates inter-node link frames for communication with other radio base stations as part of the time-division multiplex frames that make up the transmitted and received radio signals.
The frequency for transmitting the inter-node link frame to the other radio base station is determined based on the orientation to the other radio base station to which the inter-node link frame is transmitted to the radio base station. Frequency determination part and
A radio base station having a communication unit that transmits a link frame between nodes assigned by the frame allocation unit using the frequency determined by the frequency determination unit at the frequency and the timing assigned to the radio base station.
(Appendix 2) It has a storage unit that stores the orientation and the frequency in advance in association with each other.
The frequency determination unit reads a frequency associated with the direction to the other radio base station to which the inter-node link frame is transmitted from the storage unit, and reads the read frequency from the other radio base. The radio base station according to Appendix 1, which is determined as a frequency for transmitting the inter-node link frame to the station.
(Appendix 3) As the orientation, a transmission orientation for transmitting the inter-node link frame and a reception orientation for receiving the inter-node link frame are set in advance.
When the direction to the other radio base station to which the inter-node link frame is transmitted with respect to the radio base station is the reception direction, the frequency determination unit is a radio base station arranged in the transmission direction. Determine the frequency for transmitting the inter-node link frame to a relay radio base station,
The radio base station according to Appendix 1 or 2, wherein the communication unit transmits a link frame between nodes to the other radio base station via the relay radio base station using the determined frequency.
(Supplementary Note 4) The radio according to any one of Supplementary note 1 to 3, wherein the frame allocation unit allocates the inter-node link frame between the downlink frame and the uplink frame of the time division multiplexing frame. base station.
(Appendix 5) As the inter-node link frame, the frame allocation unit includes a first inter-node link frame for transmitting a signal from the radio base station to the other radio base station, and the other radio base station. The radio base station according to any one of Supplementary note 1 to 4, which is assigned a second internode link frame for receiving the signal transmitted from the radio base station.
(Appendix 6) A wireless communication terminal
A frame allocation unit that allocates inter-node link frames for communication with other wireless communication terminals as part of the time-division multiplex frames that make up the transmitted and received wireless signals.
The frequency for transmitting the inter-node link frame to the other wireless communication terminal is determined based on the orientation of the inter-node link frame to the other wireless communication terminal to the wireless communication terminal. Frequency determination part and
A wireless communication terminal having a communication unit that transmits a link frame between nodes assigned by the frame allocation unit using the frequency determined by the frequency determination unit at the frequency and the timing assigned to the wireless communication terminal.
(Appendix 7) A wireless communication method performed by a wireless base station.
The process of allocating inter-node link frames for communication with other wireless base stations to a part of the time-division multiplex frames that make up the transmitted and received wireless signals,
The frequency for transmitting the inter-node link frame to the other radio base station is determined based on the direction to the other radio base station to which the inter-node link frame is transmitted to the radio base station. Processing and
A wireless communication method that performs a process of transmitting the assigned inter-node link frame using the determined frequency at the frequency and the timing assigned to the radio base station.
(Appendix 8) A wireless communication method performed by a wireless communication terminal.
A process of allocating an inter-node link frame for communication with another wireless communication terminal to a part of the time-division multiplex frame constituting the transmitted / received wireless signal, and
The frequency for transmitting the inter-node link frame to the other wireless communication terminal is determined based on the direction to the other wireless communication terminal to which the inter-node link frame is transmitted to the wireless communication terminal. Processing and
A wireless communication method that performs a process of transmitting the assigned inter-node link frame using the determined frequency at the frequency and the timing assigned to the wireless communication terminal.
(Appendix 9) For wireless base stations,
A procedure for allocating inter-node link frames for communication with other radio base stations as part of the time-division multiplex frames that make up the transmitted and received radio signals, and
The frequency for transmitting the inter-node link frame to the other radio base station is determined based on the direction to the other radio base station to which the inter-node link frame is transmitted to the radio base station. Procedure and
A program for executing a procedure of transmitting the assigned inter-node link frame using the determined frequency at the frequency and the timing assigned to the radio base station.
(Appendix 10) For wireless communication terminals
A procedure for allocating inter-node link frames for communication with other wireless communication terminals as part of the time-division multiplex frames that make up the transmitted and received wireless signals, and
The frequency for transmitting the inter-node link frame to the other wireless communication terminal is determined based on the direction to the other wireless communication terminal to which the inter-node link frame is transmitted to the wireless communication terminal. Procedure and
A program for executing a procedure of transmitting the assigned inter-node link frame using the determined frequency at the frequency and the timing assigned to the wireless communication terminal.

100-103,501-506,511-514 Radio base station 110,111,210,211 Frame allocation unit 120,121,220,221 Frequency determination unit 130,131,230,231 Communication unit 141,241 Storage unit 200- 206 Wireless communication terminal 300-1,400-1 Link frame between nodes

Claims (9)

It ’s a wireless base station,
A frame allocation unit that allocates inter-node link frames for communication with other radio base stations as part of the time-division multiplex frames that make up the transmitted and received radio signals.
The frequency for transmitting the inter-node link frame to the other radio base station is determined based on the orientation to the other radio base station to which the inter-node link frame is transmitted to the radio base station. Frequency determination part and
The frame allocation unit node links frames allocated, using the frequency in which the frequency determination unit has determined to have a communication unit to transmit at timing allocated to the frequency and the radio base station,
As for the orientation, a transmission orientation for transmitting the inter-node link frame and a reception orientation for receiving the inter-node link frame are set in advance.
When the direction to the other radio base station to which the inter-node link frame is transmitted with respect to the radio base station is the reception direction, the frequency determination unit is a radio base station arranged in the transmission direction. Determine the frequency for transmitting the inter-node link frame to a relay radio base station,
The communication unit is a radio base station that transmits a link frame between nodes to the other radio base station via the relay radio base station using the determined frequency . In the radio base station according to claim 1,
It has a storage unit that stores the orientation and the frequency in advance in association with each other.
The frequency determination unit reads a frequency associated with the direction to the other radio base station to which the inter-node link frame is transmitted from the storage unit, and reads the read frequency from the other radio base. A radio base station determined as a frequency for transmitting the inter-node link frame to the station. In the radio base station according to claim 1 or 2 .
The frame allocation unit is a radio base station that allocates the inter-node link frame between the downlink frame and the uplink frame of the time-division multiplex frame. In the radio base station according to any one of claims 1 to 3 ,
As the inter-node link frame, the frame allocation unit is a first inter-node link frame for transmitting a signal from the radio base station to the other radio base station, and is transmitted from the other radio base station. A radio base station that allocates a second inter-node link frame for receiving a signal at the radio base station. It is a wireless communication terminal
A frame allocation unit that allocates inter-node link frames for communication with other wireless communication terminals as part of the time-division multiplex frames that make up the transmitted and received wireless signals.
The frequency for transmitting the inter-node link frame to the other wireless communication terminal is determined based on the orientation of the inter-node link frame to the other wireless communication terminal to the wireless communication terminal. Frequency determination part and
The frame allocation unit node links frames allocated, using the frequency in which the frequency determination unit has determined to have a communication unit to transmit at timing allocated to the frequency and the wireless communication terminal,
As for the orientation, a transmission orientation for transmitting the inter-node link frame and a reception orientation for receiving the inter-node link frame are set in advance.
When the direction to the other wireless communication terminal to which the inter-node link frame is transmitted with respect to the wireless communication terminal is the reception direction, the frequency determination unit is a wireless communication terminal arranged in the transmission direction. Determine the frequency for transmitting the inter-node link frame to a relay wireless communication terminal,
The communication unit is a wireless communication terminal that transmits a link frame between nodes to the other wireless communication terminal via the relay wireless communication terminal using the determined frequency . It is a wireless communication method performed by a wireless base station.
The process of allocating inter-node link frames for communication with other wireless base stations to a part of the time-division multiplex frames that make up the transmitted and received wireless signals,
The frequency for transmitting the inter-node link frame to the other radio base station is determined based on the orientation to the other radio base station to which the inter-node link frame is transmitted to the radio base station. Frequency determination processing and
The assigned node links frames, using a frequency the determined, have rows and a communication process for transmitting at a timing allocated to the frequency and the radio base station,
As for the orientation, a transmission orientation for transmitting the inter-node link frame and a reception orientation for receiving the inter-node link frame are set in advance.
When the direction to the other radio base station to which the inter-node link frame is transmitted to the radio base station is the reception direction, the frequency determination process is performed by the radio base station arranged in the transmission direction. Determine the frequency for transmitting the inter-node link frame to a relay radio base station,
The communication process is a wireless communication method in which a link frame between nodes is transmitted to the other wireless base station via the relay wireless base station using the determined frequency . It is a wireless communication method performed by a wireless communication terminal.
A process of allocating an inter-node link frame for communication with another wireless communication terminal to a part of the time-division multiplex frame constituting the transmitted / received wireless signal, and
The frequency for transmitting the inter-node link frame to the other wireless communication terminal is determined based on the orientation of the inter-node link frame to the other wireless communication terminal to the wireless communication terminal. Frequency determination processing and
The assigned node links frames, using a frequency the determined, have rows and a communication process for transmitting at a timing allocated to the frequency and the wireless communication terminal,
As for the orientation, a transmission orientation for transmitting the inter-node link frame and a reception orientation for receiving the inter-node link frame are set in advance.
When the direction to the other wireless communication terminal to which the inter-node link frame is transmitted to the wireless communication terminal is the reception direction, the frequency determination process is performed by the wireless communication terminal arranged in the transmission direction. Determine the frequency for transmitting the inter-node link frame to a relay wireless communication terminal,
The communication process is a wireless communication method in which a link frame between nodes is transmitted to the other wireless communication terminal via the relay wireless communication terminal using the determined frequency . To the wireless base station,
A procedure for allocating inter-node link frames for communication with other radio base stations as part of the time-division multiplex frames that make up the transmitted and received radio signals, and
The frequency for transmitting the inter-node link frame to the other radio base station is determined based on the orientation to the other radio base station to which the inter-node link frame is transmitted to the radio base station. Frequency determination procedure and
The purpose is to execute the communication procedure of transmitting the assigned inter-node link frame using the determined frequency at the frequency and the timing assigned to the radio base station .
As for the orientation, a transmission orientation for transmitting the inter-node link frame and a reception orientation for receiving the inter-node link frame are set in advance.
When the direction to the other radio base station to which the inter-node link frame is transmitted to the radio base station is the reception direction, the frequency determination procedure is performed by the radio base station arranged in the transmission direction. Determine the frequency for transmitting the inter-node link frame to a relay radio base station,
The communication procedure is a program for transmitting an inter-node link frame to the other radio base station via the relay radio base station using the determined frequency . For wireless communication terminals
A procedure for allocating inter-node link frames for communication with other wireless communication terminals as part of the time-division multiplex frames that make up the transmitted and received wireless signals, and
The frequency for transmitting the inter-node link frame to the other wireless communication terminal is determined based on the orientation of the inter-node link frame to the other wireless communication terminal to the wireless communication terminal. Frequency determination procedure and
The purpose is to execute the communication procedure of transmitting the assigned inter-node link frame using the determined frequency at the frequency and the timing assigned to the wireless communication terminal .
As for the orientation, a transmission orientation for transmitting the inter-node link frame and a reception orientation for receiving the inter-node link frame are set in advance.
When the direction to the other wireless communication terminal to which the inter-node link frame is transmitted to the wireless communication terminal is the reception direction, the frequency determination procedure is performed by the wireless communication terminal arranged in the transmission direction. Determine the frequency for transmitting the inter-node link frame to a relay wireless communication terminal,
The communication procedure is a program for transmitting an inter-node link frame to the other wireless communication terminal via the relay wireless communication terminal using the determined frequency .

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