JP2647118B2 - Wireless communication method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a wireless communication system in which a node station used for a LAN (Local Area Network) or the like is wirelessly connected to a terminal station.

(Prior Art) In recent years, private communication networks and the like have come to be widely used. For example, a LAN or the like is used for a computer, a FAX data terminal, and the like because it is used for data transmission. In addition, in today's buildings and offices, transmission of information data has become indispensable together with public telephone lines. On the other hand, the use of cordless terminals has begun to increase as seen in cordless phones. In addition, wiring and construction of terminals require enormous costs in buildings and offices, and it is expected that cost reductions can be achieved by making the wiring and construction unnecessary and cordless (IEEE Co.
mmunication Magazine July 1987 Vol25.No.7, P.95-P.
As described above, as the cordless operation progresses, there is a terminal station that is in a semi-fixed state, that is, that is moving or fixed.

As a conventional system, a case will be described below in which a center and a terminal station in a semi-fixed state wirelessly exchange information via a base station existing in each area. The case where the center attempts to transmit information to a certain terminal station will be described. On the center side, since each terminal station is in a semi-fixed state, it is not known in which area the terminal station that wants to transmit information is located. Therefore, the center transmits information wirelessly using base stations located in each area.

Since the terminal station is located in some area, information transmitted to all areas is received by the terminal station. On the other hand, when information is transmitted to a fixed terminal using a wired circuit such as a LAN, the information is simply transmitted to a transmission path such as a LAN and is received by a partner terminal station.
However, when transmitting information wirelessly, the terminal is not always fixed and may move. In this case, since the location where the terminal station is located is unknown, it is necessary to transmit information to the entire area that is the wireless reach. Unless information is transmitted to all areas, information is not received by a terminal station that wants to transmit information.

As described above, a terminal station to which information is to be transmitted cannot exist in the whole area of the wireless reach, but exists in a part of this area. Therefore, the consumption of the transmission power for transmitting to the area where the terminal station does not exist is wasted.

(Problems to be Solved by the Invention) As described above, in the conventional wireless communication system, when information is transmitted to a terminal station whose area is unknown due to movement, the center is provided in all areas. Information was transmitted from the installed base station. Therefore, information is transmitted to an area where there is no terminal station on the other side to which the information is transmitted, and there is a disadvantage that transmission power is wasted.

The present invention provides a radio communication system in which a base station having a history transmits an information signal from a terminal station to a mobile station based on a history at a base that handles an information signal from the mobile station. It is intended for.

[Configuration of the invention]

(Means for Solving the Problems) In order to achieve the above object, according to the present invention, a terminal station transmits, to a plurality of base stations via a transmission path, information to which a mobile station specific signal is added. In a wireless communication system that transmits and receives signals and each base station transmits and receives the information signal to and from a mobile station by radio, the plurality of base stations are connected to the terminal station by the base station. A storage unit for storing a signal unique to the mobile station that has transmitted and received, a signal detection unit for detecting the information signal on the transmission path transmitted from the terminal station, A comparison unit that compares the mobile station-specific signal added to the information signal detected by the detection unit with a signal stored in the storage unit, and the comparison unit uses the comparison unit to generate a signal unique to the mobile station. And stored in the storage unit The base station whose signal coincides preferentially transmits the information signal to the mobile station.

(Operation) The base station transmits the information signal transmitted from the mobile station to the terminal station via the transmission path. At this time,
The base station that has transmitted the information signal to the terminal station stores the mobile station-specific signal added to the information signal in the storage unit. Conversely, when transmitting an information signal from a terminal station to a mobile station, the terminal station transmits the information signal to a transmission path. Each base station detects an information signal on the transmission path by a signal detection unit. The signal unique to the mobile station added to the detected information signal is compared with the signal stored in the storage unit by the comparison unit. By this comparison, the base station in which the signal unique to the mobile station and the signal stored in the storage unit match,
An information signal is transmitted to the mobile station. As described above, since only a limited number of base stations transmit information signals, transmission power for all base stations can be saved.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram showing one embodiment of the present invention. This will be described below with reference to FIG. The terminal station 1 is connected to a transmission path such as CSMA / CDLAN. This transmission line 2 has a plurality of base stations, for example, three base stations 3, 4,.
5 is connected. Mobile stations 6 and 7 that transmit and receive data and the like exist within the range of radio waves from the base stations 3, 4, and 5. An information signal is transmitted between the terminal station 1 and the mobile stations 6 and 7. First, a case will be described in which the mobile station 6 transmits to the terminal station 1 an information signal to which a signal unique to the mobile station 6, such as a packet, is added. It is assumed that the signal transmitted from the mobile station 6 is received by, for example, the base stations 3 and 5. Base stations 3,5
Measures the received electric field strength of the information signal, and the base station 3 transmits the information signal to the transmission path 2 in a case where the signal electric field strength is stronger. The detailed description will be described later in conjunction with FIG.
The transmitted information signal is transmitted to the terminal station 1 via the transmission path 2. At the same time, a signal unique to the mobile station added to this information signal is stored in the base station 3 having the highest received electric field strength. Conversely, a case where an information signal is transmitted from the terminal station 1 to the mobile station 6 will be described below. The terminal station 1 adds a signal unique to the mobile station 6 to an information signal to be transmitted, which is composed of a packet, for example, and transmits the information signal to the transmission path 2. Each of the base stations 3, 4, and 5 constantly detects a signal on the transmission path 2.
Then, the signal is compared with the mobile station-specific signal stored in each of the base stations 3, 4, and 5. As a result of the comparison, if the signals unique to the mobile station match, the matched base station 3 transmits an information signal to the mobile station 6 in this case.

The operation of each unit will be described below with reference to one configuration diagram of the base station 30 shown in FIG. 2A and one configuration diagram of the mobile station 31 shown in FIG. 2B. A signal flow from when the information signal is transmitted from the mobile station 31 to the base station 30 and transmitted to the transmission path will be described. First, information is input to the mobile station 31 shown in FIG. 2 (b). An information signal is generated by the information signal generation unit 23 based on the input information. The unique signal of the mobile station 31 is added to the generated information signal by the unique signal adding unit 22. The information signal to which the signal unique to the mobile station 31 is added is transmitted from the transmission / reception unit 21 via the antenna 20.
The information signal transmitted via the antenna 20 is received by the transmission / reception unit 11 via the antenna 10 of the base station 30 shown in FIG. Transmitter / receiver unit 11
The received electric field strength of the information signal received at is measured. The measured reception electric field intensity value is compared with a chart stored in the memory 12. In the memory 12, a chart of the delay transmission start time corresponding to each received electric field strength value is stored. Therefore, the delay transmission start time corresponding to the measured reception electric field strength value is read from the memory 12, and by this delay transmission start time, it is determined whether another base station has transmitted the same information signal on the transmission path by the signal. Let's take a look at the detection unit 19.
If another base station does not transmit the same information signal on the transmission line by this delay transmission start time, the information signal transmission unit 14 transmits an information signal onto the transmission line at the delay transmission start time.
If the same information signal is transmitted from another base station by the delay transmission start time, the transmission of the information signal is stopped. On the other hand, at the same time when the information signal is input to the information signal transmission unit 14, the unique signal detection unit 15 detects the signal unique to the mobile station 31 added to the information signal. This detected mobile station 31
The unique signal is stored in the unique signal storage unit 16. Also,
The signal detector 19 sends the signal to the terminal station on the transmission path and
When the information signal to which the 31 unique signal is added is detected, the unique signal detecting unit 15 detects the signal unique to the mobile station 31 added to the information signal, and is stored in the unique signal storage unit 16. The mobile station 31 deletes a signal unique to the mobile station 31.

Next, an information signal is transmitted from the terminal station via the transmission path to the base station 30.
The signal flow from transmission to the mobile station 31 will be described. The terminal station sends out an information signal to which a signal unique to the mobile station 31 is added on a transmission path. The signal on the transmission path is detected by each base station. For example, a case where an information signal is detected by the base station 30 will be described below. As shown in FIG. 2A, a unique signal of the mobile station 31 is detected by the unique signal detection unit 18 from the information signal detected by the signal detection unit 19. The detected unique signal of the mobile station 31 is input to the comparing unit 17. The comparison unit 17 compares the signal with the signal stored in the unique signal storage unit 16. If the detected signal unique to the mobile station 31 is not stored in the unique signal storage unit 16,
The transmission of this information signal is stopped. If the comparison results in a match, the information signal is transmitted from the transmission / reception unit 11 to the mobile station 31 via the antenna 10. As shown in FIG. 2 (b), the transmitted information signal is
The signal is received by the transmission / reception unit 21 via the antenna 20. From the received information signal, the additional signal is removed by the additional signal separation unit 24, and the information signal is output from the information signal conversion unit 25 as information.

 FIG. 3 shows a temporal flow of the present system.

The mobile station 6 sends out an information signal such as a packet. The base station 3 which has received it transmits an information signal such as the same packet to the transmission path, and the terminal station 1 receives it. Terminal station 1
Transmits to the mobile station 6 an information signal such as packet data which is a reply thereto. The base station 3 sends it out wirelessly. Further, if the mobile station 6 emits a packet, and the base station 4 receives the data and sends the data to the transmission line, the base station 4 transmits the information signal the next time the terminal station 1 transmits an information signal such as a packet. It transmits to the mobile station 6 by radio.

Next, FIG. 4 (a) will be described below using an example of a packet which is an information signal on a transmission line. A destination address and a transmitting station address are added to this packet.

FIG. 3B shows an example of the mobile station address. A mobile station unique signal indicating that the mobile station is a mobile station is added to the mobile station address. Therefore, the base station monitors the packet in which the unique signal of the mobile station is attached to any of the destination address and the transmission station address added to the information signal which is the packet flowing on the transmission line, so that the mobile station can You can know which base station exists around.

 FIG. 5 shows another embodiment.

The transmission path 44 is a ring-shaped token ring, and when transmitting a packet to the transmission path 44, all the base stations 40, 41, 42
It is controlled so that the packet can be heard.
In this way, even a ring-shaped transmission path can be used.

According to the above-mentioned method, all base stations can be easily installed, so that equipment can be easily added. In addition, by installing many base stations, the range of radio waves can be narrowed and transmission can be performed with low transmission power.

〔The invention's effect〕

As described in detail above, according to the present invention, a base station that has transmitted an information signal from a mobile station to a terminal station in the past stores a signal unique to the mobile station, and the stored signal includes:
By comparing with the information signal transmitted from the terminal station, the base station which transmits this information signal to the mobile station is determined. Therefore, since the determined base station transmits the information signal, waste of transmission power can be prevented as compared with the conventional case where all base stations transmit to the mobile station. In addition, since the mobile station exists around the base station in which the signal unique to the mobile station is stored, the location of the mobile station can be generally determined from the storage contents of the storage unit.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing one embodiment of the present invention, and FIG.
FIG. 3 is a diagram showing one configuration of a base station and a mobile station of the present invention, FIG. 3 is a diagram showing a temporal flow of the present system, FIG. 4 is a diagram showing an example of a signal configuration of the present invention, FIG. FIG. 7 is a view showing another embodiment of the present invention. 1,43 ... Terminal station, 3,4,5,30,40,41,42 ... Base station, 6,7,3
1, mobile station, 2,44 transmission line, 11,21 transmission / reception unit, 16
... Unique signal storage unit, 17 comparison unit, 19 signal detection unit.

Claims (5)

(57) [Claims] A radio base station for transmitting or receiving a radio signal to / from a mobile station is provided so that a terminal station connected to a plurality of radio base stations via a transmission path and the mobile station are connected to the radio station. In a wireless communication method for performing communication by relaying a base station, the plurality of wireless base stations respectively monitor a transmitting station address and a destination address of packet data transmitted to a transmission line, and a mobile station to be transmitted to a terminal station. When a predetermined radio base station receives a radio signal from the mobile station, the terminal station transmits a radio signal to the mobile station via the predetermined radio base station from which the radio signal was received. Wireless communication method. 2. A mobile station that transmits or receives a radio signal between a terminal station to which a plurality of radio base stations are connected via a transmission path and a radio base station, relays the radio base station. In the wireless communication method for performing communication, each of the plurality of wireless base stations monitors a transmission station address and a destination address of packet data transmitted to a transmission path, and transmits a radio signal from a terminal station to be transmitted to a mobile station to a predetermined number. Wherein the mobile station transmits a radio signal to a terminal station via a predetermined radio base station to which the radio signal has been transmitted. 3. The radio base station according to claim 1, wherein the plurality of radio base stations store identification signals unique to mobile stations that have communicated in the past and compare the identification signals with newly received identification numbers of the mobile stations. 3. The wireless communication method according to claim 1, wherein it is determined whether or not the mobile station has performed the operation. 4. The plurality of radio base stations store identification signals unique to mobile stations that have communicated in the past, and the number of identification signals stored in the storage unit exceeds a predetermined number. In this case, the stored identification signal is erased, a new identification signal is stored, and then compared with the newly received identification number of the mobile station to determine whether the mobile station has communicated in the past. The wireless communication method according to claim 1, wherein the determination is made. 5. The mobile station according to claim 1, wherein when the received signal strength of the radio signal received from the mobile station is equal to or greater than a predetermined value, the plurality of radio base stations store an identification signal unique to the mobile station. The wireless communication method according to claim 1, wherein it is determined whether the mobile station has communicated with the mobile station in the past by comparing the identification number with the identification number.