JP2003298496A - Single frequency network system and repeater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication system configuring a single frequency network suitable for use in a comparatively narrow area and to provide a repeater. <P>SOLUTION: The single frequency network system has one transmission antenna and a plurality of reception antennas. The reception antennas comprise repeaters 10a to 10d capable of adaptive array processing and a plurality of user terminals 20a, 20b. Before start of communication, the repeaters and each communication apparatus of the user terminals acquire information representative of ease of communication with other communication apparatuses. Then each repeater informs the other communication apparatuses about the information representative of ease of communication so as to share the information. A central station being one of the repeaters informs each relay station about the weight information of the adaptive array to be used so that the communication is correctly performed in response to a communication request from the user terminal on the basis of the information representative of ease of the communication. The user terminal performs the communication via each relay station to which the weight information is set. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a repeater for amplifying and outputting an input signal, and more particularly to a single frequency network system (SFN: Single) suitable for use in a relatively narrow area such as a home. Frequency Network) and a repeater used for this.

[0002]

2. Description of the Related Art Orthogonal Frequency Division Multiplexing (OFDM), which is one of the multi-carrier modulation schemes that is said to be suitable for broadband communication.
There is a movement to construct a single frequency network using the n multiplexing) modulation method. OFDM is a multi-carrier transmission method, and has an advantage that the influence of a delayed wave within a time corresponding to the guard interval length can be eliminated by adding a guard interval to each OFDM symbol.

Utilizing this property, an SFN repeater is actively researched and developed as an antenna for terrestrial digital broadcasting. When the OFDM modulation method is used as a repeater for broadcasting, the power of the received signal is amplified and transmitted in order to increase the area that can be covered by broadcasting. Since the feedback path exists in space for the receiving antenna, oscillation may occur unless the gain of this feedback is made sufficiently small. Therefore, in order to reduce the gain of the transmission / reception antenna, one omnidirectional antenna is used as the transmission antenna, and an array antenna is composed of a plurality of omnidirectional antennas as the reception antenna. Various methods have been proposed in which the sex pattern is adjusted so that the null is oriented in the direction of the transmitting antenna to provide isolation between the transmitting and receiving antennas. Such technology is
For example, Japanese Patent Laid-Open Nos. 2001-136115 and 200
It is disclosed in JP-A 1-223628.

[0004]

In the above conventional method, since it is assumed that SFN is applied to a form of broadcasting, only isolation between transmitting and receiving antennas of one repeater is considered. It was enough. However, a problem arises when trying to apply this SFN to a home network.

SFN for home (home) networks
The advantages of applying are as follows. As a home network, it is difficult to easily connect a wired network in the house, so the wireless scenario is the most dominant. When building a home network wirelessly, a single cell network (one base station or one access point) is advantageous. This is because it is almost unthinkable to perform a multi-cell operation by placing a plurality of base stations in a home like a public system. The reason why the multi-cell is not appropriate is that when a plurality of base stations are placed, wired wiring between the base stations is required, and a wired network has to be laid in the house. Therefore, wireless and single-cell networks are promising in the home.

[0006] Then, what becomes a problem is co-channel interference between adjacent houses. As a method of removing co-channel interference, there are a method of using different frequencies and a method of accessing in a time division manner, but all of them deteriorate the frequency utilization efficiency. The essence of the problem is that since it has to be a single cell, it must be transmitted with appropriate power so that radio waves can be received from end to end of the house and received, and the radio waves interfere with each other. It means that the range to give is increased. Also, as shown in FIG. 1, the shape of the house is not a circle but a combination of rectangles. Therefore, when trying to communicate with a terminal in an arbitrary area inside the house, the range that gives interference must be large. Interference with similar networks in adjacent homes becomes a problem. In the example of FIG. 1, three houses 31, 3
2 and 33 are adjacent to each other, and each house is a terminal 311, 312, 31 that constitutes a separate network.
3; 321, 322; 331, 332, 333. For example, focusing on the terminal 331 in the house 33, the cell range 35 is the terminal 3 in the farthest position in the same house.
33, but simultaneously includes the terminal 311 of the house 31 and the terminal 321 of the house 32 which are adjacent to each other.

When an adaptive array antenna is used to remove interference, it is necessary to mount a plurality of antennas on each user terminal itself, which is a cost problem.

As a means for solving these problems, a method is conceivable in which signals are transmitted from each user terminal with a small amount of power, and the signals are relayed by a plurality of relays to the target user terminal. By using this method, the interference area that affects the radio waves and the shape of the house are almost the same, and there is an advantage that the useless interference area does not spread widely outside the house.

As described above, when a plurality of repeaters are dispersedly arranged in a house, radio waves having the same information will fly from the plurality of repeaters. That is, it is not the case that only the isolation between the transmitting and receiving antennas of one repeater needs to be taken into consideration, which has been considered in the prior art. When there is the first repeater and the second repeater, the output of the first repeater and the output of the second repeater output the same information although there is a slight time lag. First
It is necessary to direct the null having directivity so that the repeater does not receive the transmission signal of the first repeater and also does not receive the transmission signal of the second repeater. At the same time, there are many multipaths reflected by walls in the house, and it is necessary to direct nulls in those directions as well. However, if the output signals of all the repeaters are not received, the system will fail. That is, in order to propagate information, it is necessary to receive only the output of a specific repeater and not receive the output of other repeaters. A method of specifying the repeater is also one of the problems.

The present invention has been made in such a background, and an object thereof is to provide a communication system forming a single frequency network suitable for use in a relatively small area.

Another object of the present invention is to provide a repeater suitable for constructing such a communication system.

[0012]

A single frequency network system according to the present invention has one transmitting antenna and a plurality of receiving antennas, and the receiving antenna is used by a user and a repeater capable of adaptive array processing. In a single frequency network system composed of multiple user terminals, prior to transmitting data from one user terminal to another user terminal, the weight of the adaptive array to be used by each repeater suitable for the communication concerned The feature is that the pattern is dynamically set.

By using a repeater capable of adaptive array processing in this way, a wireless only network is provided. In addition, before transmitting data from one user terminal to another user terminal, the weighting pattern of the adaptive array to be used by each repeater suitable for the communication is dynamically set for each user terminal pair. Therefore, co-channel interference with a neighbor can be minimized.

Specifically, before starting communication, each communication device of the repeater and the user terminal acquires information indicating the ease of communication with another communication device. Then, each repeater notifies the other communication device of the information on the ease of communication by using a dedicated divided time slot. The central station selected from all the repeaters is used for each relay station so that the communication is performed correctly based on the communication request from the user terminal notified by using the dedicated division time slot. The weight information of the adaptive array to be notified is notified.
After the appropriate weight is set in each relay in this way, communication between the user terminals is started.

More specifically, at the time of initial setting, information on the ease of communication when each of the communication devices simultaneously transmits a known signal and each communication device receives a known signal from another communication device. A known signal transmission area for obtaining the information, and a plurality of information sharing areas following the area, each information sharing area is provided with a dedicated division time slot for transmitting information by each communication device, and the plurality of information sharing areas are provided. Through each, the relays share information on the ease of communication between all the communication devices.

The central station preferably uses the relays to be used in mutual communication between a plurality of user terminals based on the information indicating the ease of communication between each communication device and another communication device. And a means for determining the relay path of the relay and holding the weight information of the adaptive array of each relay corresponding to this relay path.

Based on the communication request from the user terminal, the central station transmits the weight information of the adaptive array of each repeater corresponding to the communication to the repeater, and the repeater receiving this transmission receives the corresponding information. The weight of its own adaptive array is set according to the weight information.

The central station preferably transmits the adaptive array to be used by each relay when transferring a transmission request from each user terminal to the central station and when notifying the weight information from the central station to each relay. It further comprises means for predetermining weight information and transmitting it to each repeater.

Prior to the communication area for communication between user terminals, a communication request area for a user terminal that wants to transmit data to make a communication request to the central station, and a central station that receives this communication request A weight setting area for notifying and setting the weight information to be used by each relay for transmitting the data to the relay is provided, and at least each data terminal can issue a communication request in the communication request area. A dedicated divided time slot that can be provided is provided, and in the weight setting area, at least a divided time slot dedicated to each relay that notifies the corresponding weight information to each relay is provided, and in each of the communication request area and the weight setting area. In the divided time slots, each divided time slot is assigned according to the weight information of the adaptive array so that the corresponding communication device can communicate with the central office. The weight of each repeater is switched on every Tsu door.

A repeater according to the present invention is a repeater used in a single frequency network system, and comprises a plurality of receiving antennas, a plurality of receiving circuits corresponding to the receiving antennas, and outputs of the plurality of receiving circuits. A plurality of weight processing means for performing weighted addition processing and calculating and storing the weight information, a selection means for selecting one of the plurality of weight processing means, and a transmission for transmitting the output of the selected weight processing means A circuit, a transmitting antenna connected to the transmitting circuit, a means for receiving and storing information on the ease of mutual communication between other communication devices of a repeater and a data terminal that form a network, and a user terminal A user terminal, which is provided in advance of a communication area for communication between users, who wants to transmit data makes a communication request to a repeater as a central station. In the signal request area and the weight setting area in which the central station that receives this communication request notifies the other relays of weight information to be used by the relay to transmit the data, and sets the weight information. It is characterized by further comprising: control means for switching the selection of the weight processing means in sequence according to predetermined weight information for each divided time slot provided exclusively for the communication device.

In this repeater, preferably, the first data table storing at least the selection information of the weight processing means to be used by itself at the time of communication between arbitrary data terminals and the repeater selected as the central station. On the other hand, when any data terminal makes a communication request, a second data table storing at least selection information of weight processing means to be used by itself in the divided time slots assigned to each data terminal, and communication between user terminals When the central station notifies each repeater of the selection information of the weight processing means that each repeater should use, the selection information of the weight processing means that each repeater should use in the divided time slot corresponding to each repeater A third data table stored therein, and the control means sends a communication request from a certain data terminal prior to communication from the certain data terminal to another data terminal. In this case, the selection information of the corresponding weight processing means specified in the second table is sequentially selected at least during the division time slot allocated to each data terminal, and then the central station transmits data to each repeater. When notifying the weighting pattern to be used during the communication between the terminals, at least at the time divisional slots corresponding to the respective relays, the selection information of the corresponding weighting processing means designated in the third table is sequentially selected, and the certain data is selected. At the time of communication from a terminal to another data terminal, the selection information of the weight processing means corresponding to the data terminal of the transmission and the reception is selected by referring to the first table.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 2A shows the structure of the repeater used in the present invention. The repeater 10 includes a plurality of omnidirectional antenna elements 1
11n are provided as receiving antennas. The signals from the respective antennas are received by the receiving analog modules (RX_RF) 12a, 12b, ...
12n, the adaptive array antenna signal processing unit 14, and the transmitting analog module (TX_R
F) Transmit to space by one omnidirectional transmitting antenna 17 via 16.

FIG. 2B shows an example of the internal configuration of the adaptive array antenna signal processing section 14. In this example, the adaptive array antenna signal processing unit 14 has 31 weight processing units 140-1 to 140 of the same configuration that operate simultaneously.
It has -31. The outputs of these weight processing units are input to the weight coefficient pattern selection unit 149, and one output is selectively output to the transmission analog module 16. The weighting factor pattern selection unit 149 is controlled based on the output of the repeater control table storage unit 148. Further, the operation of each weight processing unit and the repeater control table storage unit 148 is controlled by the control unit 147. Each weight processing unit calculates the receiving weight coefficient calculating and storing unit 143, a plurality of multipliers 141a to 141n for multiplying the output of the receiving analog modules 12a, 12b, ... 12n by the weight coefficient, and these outputs. And an adder 142 for adding. The reception weighting factor calculation and storage unit 143 determines the weighting factor to be given to each multiplier based on the received signal and the known signal 145 at the time of initialization described later, and as shown in FIG. Memorize as. The known signal is a signal unique to each repeater and terminal (collectively referred to as a communication device), and is known data used for weight learning of the repeater. As such known data, for example, random pattern data different from each other can be used. 31 weight processing units 140-1 to 140-1
140-31 means that up to 31 repeaters and terminals can be simultaneously supported.

The repeater control table storage unit 148 stores the weighting coefficient pattern (also simply referred to as a weighting pattern) to be adopted by each repeater when communicating from one terminal to another terminal.
This is a part that is stored as a repeater control table prior to communication. As shown in FIG. 12, this table stores information (for example, pattern numbers # 1 to # 31) for specifying the weighting pattern to be adopted by each relay at the time of communication, for each different combination of the transmitting terminal and the receiving terminal. The data table 120 (first data table) held, and the communication request area (time) when an arbitrary user terminal makes a communication request to a central station described later, as shown in FIGS. Data table 1 which defines the weighting pattern to be sequentially used by each repeater in each divided time slot
30 (second data table) and, conversely, when the central station notifies each repeater of the weight pattern to be adopted by each repeater during the next communication between user terminals, the weight setting area (time area) 52 It is a data table 135 (third data table) that defines a weighting pattern that each repeater should sequentially use in each divided time slot. These pattern numbers correspond to the 31 weight processing units 140-1 to 140- described above.
It corresponds to each of the reception weighting coefficient calculation 31 and the individual weighting pattern stored in the storage unit 143. These data tables 130 and 135 are shared by all the repeaters in this embodiment. Each repeater only refers to the data portion specified for it.

FIG. 3 shows the configuration of the user terminal 20 used in this embodiment. The user terminal 20 has one antenna 21 and uses the same antenna for both transmission and reception. An analog module TX_RF) 26 for transmission and an analog module (RX_RF) 25 for reception are connected to the antenna 21 via a switch (SW) 23. These analog modules 25 and 26 are further connected to a modulation / demodulation unit (DM).
OD & MOD) 27. Modulator / demodulator 27
Is connected to a higher-order control unit (not shown), and this control unit is further connected to a user interface unit such as an operation unit and a display unit. In the present embodiment, the configuration and operation of the user terminal 20 are the same as the conventional ones, and thus will not be described in detail.

A specific operation example of the operation of this embodiment will be described below.

As an example, as shown in FIG. 7, repeaters A, B, C (10a, 10b, 10c) and terminals 20a, 20b as transmitters and receivers are arranged, and data from the terminal 20a is arranged. Let us consider a case where it is desired to relay to the terminal 20b in the order of the relays A, B, and C, and finally to relay the relay to the terminal 20b. Here, for the sake of explanation, the terminal 20a transmits only,
The terminal 20b considers only reception. The input adaptive array antenna of the repeater A adjusts the directivity of the antenna so as to receive only the output from the transmitter, and the repeater A,
The weights of the array antennas are learned so that the nulls are directed toward the output antennas of B and C. The repeater B adjusts the directivity of the antenna so as to receive only the output of the repeater A,
The weights of the antennas are learned so that the nulls are directed toward the output antennas of the transmitter, the repeater B, and the repeater C. Repeater C
Adjusts the directivity of the antenna so as to receive only the output of the repeater B, and learns the weight of the antenna so as to direct the null toward the output antenna of the transmitter, the repeater A, and the repeater C.

The operation of this embodiment is roughly divided into an operation at the time of initial setting and an operation at the time of normal operation. In the example of FIG. 7, the user has specified the route of the relay by the relay, but in reality, the system automatically determines and determines this route. Such automatic route determination processing is performed at the time of initial setting.

Not all user terminals and repeaters can communicate directly. Therefore, prior to actual operation, the user terminal and the repeater need to recognize each other's existence and to recognize which user terminal the communication to be performed is from which user terminal to which user terminal. . This needs to be recognized by all repeaters in common. First, the initial operation for that will be described. FIG. 9 is a flowchart showing the operation at the time of initial setting.

Each user terminal and the repeater issue a beacon, and listen to each other to autonomously and decentralize frame synchronization (S11). This can be done using a conventional method or the like. A unique number (authorization code) is assigned in advance to the user terminal and the repeater. Here, maximum 3
Two units can be registered. 32 units is the total number of user terminals and repeaters. The unique number can be set manually by the user.

Similar to the above, consider the case where there are a transmitter and a receiver, and a repeater A, a repeater B and a repeater C. Repeater A, B, C in order, or B, C, A or C, A,
Whether to relay in the order of B actually depends on the positions of the relay and the positions of the transmitter and the receiver. This positional relationship is automatically grasped prior to data transmission and reception, and the relay route is determined. The method for doing so is as follows.

First, the array antenna is learned by the known signal in each repeater (S12). Each relay has a desired signal power to an interference signal power SIR when one of the output signals from the transmitter or a relay other than itself is a desired signal and the other output signals are interference signal powers.
(Signal Interference Ratio) or desired signal power vs. interference noise signal power SINR (Signal Interference Nois)
e Ratio) is calculated. For example, the repeater A is the repeater B
, A weight is calculated so as to receive a known signal from, a SIR (B) when received using the weight is calculated, and a weight is calculated so as to receive a known signal from the repeater C, The SIR (C) when received using the weight is calculated, the weight is calculated so as to receive the known signal from the transmitter, and the SIR when received using the weight is calculated.
Calculate (TX). In this way, a total of three types of SI
Calculate R. In networks where there are still other repeaters and transmitters, the SIR is calculated for each of them. Similarly, the same calculation is performed for the repeaters B and C.

More specifically, prior to the actual transmission of data, each repeater and each terminal constituting the network transmits the above-mentioned unique known signal from the transmitting antenna at a constant cycle. In the present embodiment, as shown in FIG. 4, for example, the initial setting frame is provided once in a plurality of communication frames with a frame interval of 2 ms.
The initial setting operation is executed in the initial setting frame. The proper value of “plurality of times” may change depending on the application and the situation, but is 1000 times in the present embodiment. The initial setting frame includes a known signal transmission area 411 and a plurality of information sharing areas 1 to N (412a to 412N) following the known signal transmission area 411.

Within the known signal transmission area 411, each repeater and terminal produces a known signal, and each repeater receives its authorization code from another repeater and terminal by means of an adaptive array antenna at its receiver side. A known signal corresponding to is received. At this time, each repeater learns the weighting coefficient for each repeater and each terminal other than itself so as to form the directivity so as to receive only the output of the terminal or the repeater. For that purpose, for example, RLS (Recursive Least Square) using MMSE (Minimum Mean Square Error) as an evaluation criterion.
An algorithm or the like is used. When the above SIR is calculated, it is possible to mutually obtain the SIR which is the value of the ease of communication between the relays and the transceivers.

Next, the SI of the communication device corresponding to each unique number
Make R known to each communication device. Even if each communication device can communicate with only some communication devices, all the communication devices communicate with each other by repeating this information transmission by complete time division for a plurality of cycles (N times in FIG. 4, for example, 20 times). Can be shared (S13, S14).

In the present embodiment, a special channel is used for communication in order to share the SIR information with each other. The special channel is a predetermined area (information sharing area) in a frame (initial setting frame) provided for transmitting this SIR information once in a plurality of frames. Information is transmitted while avoiding interference by time division multiplexing in which time (time slot) is uniquely assigned to the transceiver. Since this information is transmitted with low power, it only reaches nearby repeaters or transceivers. The repeater or transmitter / receiver that has received the signal adds the SIR information held by itself in the time slot allocated for itself and transmits the information. A plurality of information sharing areas 412a to 412 following the known signal transmission area 411 of FIG.
Each area of 12N is a complete time division area (information sharing area) in which a unique time slot is assigned to each communication device (user terminal and repeater). In this example, time slots from the communication device 0 to the communication device 31 are provided, and in each time slot, only that communication device transmits information to other communication devices. Of course, there may be a communicator that can correctly receive this information and a communicator that does not. However, the operation in which the communication device that has succeeded in reception sequentially adds the information held by itself to the received information
Information can be shared among all the repeaters by repeating the process once.

An example of such shared information is shown in FIG.
FIG. 6 shows S between the communication devices acquired by the initial setting.
It is an IR data table 60. This table describes the SIR (dB value) indicating the ease of communication from the communication device on the transmission side to the communication device on the reception side. The number in parentheses below each dB value indicates the S
The number of the weighting pattern used when the IR value is obtained is shown. The information of these SIRs is the information individually collected in each relay, but is supplied to all the relays in the above information sharing area. However, in principle, it is sufficient if the "central office" holds this table. In the example shown,
The case of three repeaters and two user terminals is shown. The vertical axis indicates the receiving side communication device, and the horizontal axis indicates the transmitting side communication device.

Then, one repeater is selected as the central station (S15). This central office will control the communication. As a method of selecting the central station, one relay station may be fixedly determined in advance, or may be automatically determined based on table data as shown in FIG. As the latter method, the relay station that declares to be the central station earliest becomes the central station, and the relay station that requires the least number of relays to contact other communication devices becomes the relay station. Processing for automatically determining the central station can also be performed in the information sharing area.

Since the central station can decide in advance the optimum route for transmitting information to all the communication devices, it becomes possible to transmit data to each communication device. Conversely, the optimum route from each communication device to the central office is also determined. The data of the weight patterns for these optimum routes are shown in tables 130 and 135.
It transmits to each repeater as (FIG. 13) (S16). Furthermore, determine the relay route for communication between each user terminal,
A table 120 of weight patterns for each repeater for that purpose is created and stored (S17). In each relay path, basically, if the relay path is determined so as to receive the output from only one place, the closed loop does not exist, so that oscillation due to feedback does not occur.

Considering the example of FIG. 7 again, the repeater A uses only the output signal of the user terminal 1 and the output signals of the repeaters A, B, and C are weighted so as not to be received as interference. ing. Also, repeater B uses weights that have been learned to receive only the output from repeater A.
Similarly, repeater C uses weights that have been learned to receive only the output of repeater B.

When passing through the three repeaters A, B and C, possible routes are A-B-C, A-C-B,
6 of B-A-C, B-C-A, C-A-B, and C-B-A
There are two candidates, but the central office decides which can be transmitted through the higher SIR. That is, the smallest SIR among a plurality of SIRs in one route is compared for each route, and the route having the largest value is selected as the target route. Since there are at most several tens of repeaters in one house, this determination can find the optimum relay route by brute force calculation.

Next, the normal operation will be described with reference to the flowchart of FIG. This processing is performed in the communication request area 5 of FIG.
1 and the weight setting area 52 and the communication area 53 between the following user terminals. These areas are shown in FIG.
It is possible to correspond to a normal frame other than the initial setting frame.

The terminal that wants to transmit data notifies the central station of the terminal number of the other party (S21). This notification is performed within the time slot assigned to itself in the communication request area 51 (FIG. 5). That is, in each time slot, each repeater dynamically changes the weighting coefficient according to the table 130 (FIG. 13) so as to select the weighting pattern corresponding to the time slot and defined by the other party to be received by the relay station. I will do it. Thus, in each time slot in the communication request area 51, the communication path from each terminal to the central office is dynamically switched and set. The number of time slots in the communication request area 51 is sufficient if it is the number of user terminals, but in the example of the figure, 32 are provided so as to be universally applicable to all communication devices.

In the subsequent weight setting area 52, the table 135
Based on (FIG. 13), the weighting pattern of each repeater is switched in each notification time slot. Thus, in each of the time slots, the communication path from the central office to each repeater is dynamically switched and set. Also in this case, in practice, only the time slots assigned to the repeaters need to work. In these functioning time slots, each repeater is notified of the corresponding weighting pattern in the table 120 based on the unique numbers of the transmitting terminal and the receiving terminal (S22).

In the communication area 53 between the user terminals, each repeater selects the weight pattern notified in the weight setting area 52. As a result, a relay route from the requested transmission terminal to the reception terminal is established, and communication between the terminals can be performed (S23).

When communication in the reverse direction is required, a transmission request is newly transmitted from the terminal on the transmission side to the central station, and the same processing as above is performed to establish a relay path and communication is performed. I do.

FIG. 8 shows an example of the relay route inside the house. Arbitrary transmitters 20a and receivers 20b are relays 10a-10a in one house (for example, house 33) without being interfered with adjacent houses (for example, house 32).
Communication becomes possible via d. The example of FIG. 8 shows an example in which four repeaters are used.

By using the repeater in this way,
It will be possible to provide a service that enables wireless communication in every corner of the house with minimal power.

The preferred embodiment of the present invention has been described above, but various modifications and changes can be made. For example,
Although the table 120 of the weight pattern of each relay for each of the two-way communication between the terminals shown in FIG. 12 is held only in the central station and the weight pattern is notified to the relay, The same table may be held in the repeater, and the central station may instruct the repeater to identify the transmitting terminal and the receiving terminal.

Although the repeater is provided with a plurality of weight processing units to operate in parallel at the same time, a single weight processing unit is used when the weighting factors can be calculated and the switching setting can be performed at extremely high speed. May be.

[0052]

According to the present invention, in a network in a relatively narrow area, it is possible to provide a wireless only network by using a repeater even if there is only short-distance wireless communication means. Become. In addition, since it is possible to provide a communication method that minimizes co-channel interference with adjacent areas, it is possible to improve frequency utilization efficiency.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a problem of a conventional single frequency network.

FIG. 2 is a block diagram showing a schematic configuration (a) and a detailed configuration (b) of the repeater according to the embodiment of the present invention.

FIG. 3 is a block diagram showing a schematic configuration of a user terminal used in the embodiment of the present invention.

FIG. 4 is an explanatory diagram of a communication frame used in the embodiment of the present invention.

5 is an explanatory diagram of a normal frame in the communication frame of FIG.

FIG. 6 is a diagram showing a data table of SIR between respective communication devices acquired by initial setting in the embodiment of the present invention.

FIG. 7 is a diagram showing a state of communication between user terminals via a plurality of repeaters.

FIG. 8 is a diagram showing an example of a relay route inside a house according to the embodiment of the present invention.

FIG. 9 is a flowchart showing an operation at the time of initial setting in the embodiment of the present invention.

FIG. 10 is a flowchart showing a normal operation according to the embodiment of the present invention.

FIG. 11 is a diagram showing a data table stored in a reception weighting factor calculation and storage unit according to the embodiment of the present invention.

FIG. 12 is a diagram showing a data table holding information for specifying a weighting factor pattern to be adopted by each repeater at the time of communication, for each different combination of the transmitting terminal and the receiving terminal according to the embodiment of the present invention. .

FIG. 13 shows in advance the weighting factor pattern to be adopted by each repeater during communication from the central office to each repeater other than the central office, and conversely from each repeater other than the central office to the central office in the embodiment of the present invention. It is a figure which shows the defined table.

[Explanation of symbols]

10 ... Repeater, 10a-10d ... Repeater, 11a-11
n ... omnidirectional receiving antenna, 12a to 12n ... receiving analog module, 14 ... adaptive array antenna signal processing unit, 16 ... transmitting analog module, 17 ...
Omnidirectional transmission antenna, 14 ... Adaptive array antenna signal processing unit, 20 ... User terminal, 20a ... User terminal, 20b ... User terminal, 60 ... Data table, 11
0 ... data table, 120 ... data table, 130
... data table, 135 ... data table, 140-
1 to 140-31 ... Processing unit, 141a to 141n ... Multiplier, 142 ... Adder, 143 ... Storage unit, 145 ... Known signal, 149 ... Coefficient pattern selection unit, 147 ... Control unit, 1
48 ... Repeater control table storage unit, 411 ... Known signal transmission area, 412a to 412N ... Information sharing area

Claims (11)

[Claims] 1. A single-frequency network system comprising a repeater having one transmitting antenna and a plurality of receiving antennas, the receiving antenna being capable of adaptive array processing, and a plurality of user terminals used by a user. Prior to transmitting data from one user terminal to another user terminal, the weighting pattern of the adaptive array to be used by each repeater suitable for the communication is dynamically set. Frequency network system. 2. A single frequency network system comprising a repeater having one transmitting antenna and a plurality of receiving antennas, the receiving antenna being capable of adaptive array processing, and a plurality of user terminals used by a user. Before starting the communication, a means for each communication device of the repeater and the user terminal to obtain information indicating the ease of communication with another communication device, and each repeater has a dedicated division time. A means for notifying the other communication device of information on the ease of communication using a slot, and a user terminal for which the central station selected from all the repeaters is notified using a dedicated divided time slot. Based on a communication request from the single frequency network, which notifies each relay station of the weight information of the adaptive array to be used so that the communication can be performed correctly. System. 3. A known signal for initializing the setting, wherein each of the communication devices simultaneously transmits a known signal, and each communication device obtains information on ease of communication when receiving a known signal from another communication device. A transmission area and a plurality of information sharing areas following this area are provided, and each information sharing area is provided with a dedicated division time slot for transmitting information by each communication device, and all communication is performed through the plurality of information sharing areas. 3. The relays share information on the ease of communication between the machines with each other.
The described single frequency network system. 4. The central station is a repeater determined in advance from all repeaters or a repeater determined based on information of ease of communication between the communication devices. The single frequency network system according to claim 2. 5. The repeater to be used in mutual communication between a plurality of user terminals, wherein the central station is based on information indicating that each of the communication devices can easily communicate with other communication devices. 6. The single frequency network system according to claim 2 or 5, further comprising means for determining a relay path of said relay path and holding weight information of the adaptive array of each repeater corresponding to this relay path. 6. The central station, based on a communication request from a user terminal, transmits weight information of the adaptive array of each repeater corresponding to the communication to the repeater, and the repeater receiving this transmission. 3. The weight of the adaptive array is set according to the weight information.
The described single frequency network system. 7. The weight of the adaptive array to be used by each repeater, when the transmission request is transmitted from each user terminal to the central office and when the weight information is notified from each central station to each repeater. The single frequency network system according to claim 2, further comprising means for predetermining information and transmitting the information to each repeater. 8. A communication request area for a user terminal desiring to transmit data to make a communication request to a central station prior to a communication area for communication between user terminals, and a central station which has accepted this communication request. Is provided with a weight setting area for notifying and setting weight information to be used by each relay for transmitting the data to each relay, and at least each data terminal issues a communication request in the communication request area. In the weight setting area, at least a divided time slot dedicated to each relay for notifying the corresponding weight information to each relay is provided in the communication setting area and the weight setting area. In each divided time slot of each of the divided time slots in accordance with the weight information of the adaptive array so that communication between the corresponding communication device and the central station can be performed. Single frequency network system according to claim 2, wherein the weight of each repeater is switched every Tsu bets. 9. A repeater used in a single frequency network system, comprising: a plurality of receiving antennas, a plurality of receiving circuits corresponding thereto, and weighted addition processing of outputs of these plurality of receiving circuits; A plurality of weight processing means for calculating and storing weight information, a selection means for selecting one of the plurality of weight processing means, a transmission circuit for transmitting the output of the selected weight processing means, and a transmission circuit for the transmission circuit. A means for receiving and storing information on the ease of mutual communication between the connected transmitting antenna, other repeaters that make up the network, and each communication device of the data terminal, and communication for communication between user terminals A communication request area, which is provided prior to the area, for a user terminal that wants to transmit data to make a communication request to a repeater as a central station,
The central station that accepts this communication request notifies other relays of the weight information to be used by the relay for transmitting the data and sets the weight setting area, which is dedicated to each communication equipment. And a control means for sequentially switching the selection of the weight processing means in accordance with predetermined weight information for each of the divided time slots. 10. A first data table storing at least selection information of weight processing means to be used by itself during communication between arbitrary data terminals, and an arbitrary data terminal for a repeater selected as a central station. A second data table storing at least selection information of weight processing means to be used by itself in divided time slots assigned to each data terminal when a communication request is made by each relay terminal, and used by each relay during communication between user terminals Third data storing the selection information of the weight processing means to be used by each relay in the divided time slot corresponding to each relay when the central station notifies each relay of the selection information of the weight processing means to be processed. A table, the control means, at the time of making a communication request from a certain data terminal prior to communication from a certain data terminal to another data terminal, at least each data The selection information of the second corresponding weight processing unit as specified in the table are sequentially selected during the assigned division time slots at the end, then,
When the central station notifies each repeater of the weighting pattern to be used during the communication between the data terminals, the corresponding weight processing means specified in the third table at least during the divided time slots corresponding to each repeater. Select the selection information sequentially, and select the selection information of the weighting processing means corresponding to the transmitting and receiving data terminals by referring to the first table during communication from the certain data terminal to another data terminal. The repeater according to claim 9, characterized in that 11. The control means transmits information of its own known at the time of initial setting, and also obtains information of ease of communication when receiving a known signal from another communication device. Information on the ease of communication is transmitted to another repeater in the assigned dedicated divided time slot, and communication is easily performed from another communication device in the dedicated divided time slot assigned to another communication device. 11. The repeater according to claim 9, wherein information on the ease of communication between all the communication devices is collected by receiving the information on the communication quality and repeating the transmission and reception.