JP2564680B2 - Mobile radio base station system - Google Patents

Description

DETAILED DESCRIPTION [Outline] For example, in a mobile radio base station system used when a center that manages the operation of an expressway communicates with a mobile station that checks the operation status, the mobile station moves its position. However, for the purpose of ensuring that the operation management center and mobile stations can always communicate in a good S / N state, the center and multiple wireless base stations are connected via the transmission line 11 and the reception line 12. In a mobile radio base station system in which the center and mobile stations communicate in series via a radio base station, the receiver 21 of each radio base station receives at least the radio wave from the mobile station The electric field information is output, and at least the incoming electric field information of the own station and the incoming electric field information from the lower radio base station via the receiving line are input to the control logic circuit 32 in the wireless base station. When the incoming electric field information from the lower radio base station is either L or H, the control logic circuit generates a switching control signal and is controlled by the switching control signal to connect the receiving line from the lower radio base station in the own station. The reception output from the receiver 21 of the own station and the incoming electric field information H from the own station are transmitted to the receiving line to the upper radio base station, and the incoming electric field information of the own station is L and the lower radio base. When the incoming electric field information from the station is H, the control logic circuit does not generate the switching control signal, so that the receiving output from the lower radio base station via the receiving line and the incoming electric field information H at the own station are generated in the own station. It is sent to the receiving line to the upper radio base station, and the incoming electric field information from both the own station and the lower radio base station is L.
In this case, the control logic circuit generates a switching control signal, which disconnects the receiving line from the lower radio base station within the own station and the reception output of the own station and the incoming electric field information L to the upper radio base station. When it is sent to the line, the local station does not receive the radio wave from the mobile station, and the incoming electric field information from the lower radio base station is L or H, the control logic circuit does not generate the switching control signal, which causes Then, the reception output from the lower radio base station and the incoming electric field information L or H
And are transmitted to the receiving line to the upper radio base station.

[Industrial applications]

The present invention relates to a mobile radio base station system used, for example, when a center that manages the operation of a highway communicates with a mobile station that checks the operation status.

For example, information from a mobile station that is checking the operation status of an expressway is transmitted to a center that manages the operation via a plurality of mobile radio base stations linearly provided along the road, At this time, it is necessary that the center and the mobile station can always communicate in a good S / N state even if the mobile station moves from one position to another.

[Conventional technology]

 FIG. 10 shows a block diagram of a conventional example.

As shown in the figure, the call operation unit 1 of the center is connected to the radio base stations a, b, ... N via the transmission line 11 and the reception line 12, and the center is connected to the mobile station 13 via each radio base station. You can communicate with. Hereinafter, assuming that the radio base station b receives the transmission signal from the mobile station 13, the operation of the drawing will be described.

First, since the line switching relay RL _1b is driven by the operation of the squelch circuit (not shown) in the receiver 21b of the radio base station b, the contact r _{1b of} this relay becomes the state of the dotted line and the receiver 21b becomes Connect to the receiving line 12. So receiver 2
The information (reception output) from the mobile station 13 extracted in 1b is sent to the call operation device in the center via the receiving line.

At this time, the receiving line of the wireless base station which is lower than the wireless base station b is disconnected from the center by the contact point r _1b .
Even if these radio base stations receive the transmission signals of mobile stations,
The received output is not sent to the center. That is, of the radio base stations that have received the information from the mobile station, the station closest to the center is selected, and the reception output of this station is sent to the center.

On the other hand, in the center, the display unit (not shown) indicates which radio base station the information is fetched. Therefore, when the information is sent from the center to the mobile station, the address and the information corresponding to the radio base station b are manually sent through the transmission line 11 according to the display.

.. of each radio base station have a function of detecting their own address, so that information from the center is sent to the mobile station via the distributor 23b and the transmitter 22b.

In the above description, the case where the center and the mobile station transmit information via the wireless base station b has been described, but the same applies to the case of other wireless base stations.

[Problems to be Solved by the Invention]

Here, when a plurality of radio base stations receive the transmission signal transmitted from the mobile station, the information extracted from the radio base station closest to the center (the highest radio base station) is transmitted to the center as described above. . However, the incoming electric field level of the mobile station 13 is higher in the incoming electric field level in the lower radio base station than in the uppermost radio base station, and the S / N may be good.

That is, there is a problem that the center and the mobile station cannot always communicate in a good S / N state.

An object of the present invention is to enable the center and the mobile station to communicate with each other in a good S / N state at all times even if the mobile station moves from position to position.

[Means for solving the problem]

In the mobile radio base station system of the present invention, as described above, the center and a plurality of radio base stations are cascade-connected via a transmission line 11 and a reception line 12, as shown in the principle diagrams of FIGS. In a mobile radio base station system in which a center and a mobile station communicate with each other via a radio base station, in each radio base station, the receiver 21 receives at least incoming electric field information in addition to the reception output when receiving a radio wave from the mobile station. At least the incoming electric field information of the local station and the incoming electric field information from the lower radio base station via the receiving line are input to the control logic circuit 32 in the wireless base station. When the incoming electric field information from the station is either L or H, the control logic circuit generates a switching control signal, and under the control of the switching control signal, the connection of the receiving line from the lower radio base station is disconnected in the own station. With The reception output from the receiver 21 of the station and the incoming electric field information H from the own station are transmitted to the receiving line to the upper radio base station, and the incoming electric field information of the own station is L and the incoming electric field information from the lower radio base station is In the case of H, the control logic circuit does not generate the switching control signal, so that the reception output from the lower radio base station through the receiving line and the incoming electric field information H at the own station are received by the upper radio base station in the own station. The incoming electric field information sent from the local station and the lower radio base station is sent to the line
In this case, the control logic circuit generates a switching control signal, which disconnects the receiving line from the lower radio base station within the own station and the reception output of the own station and the incoming electric field information L to the upper radio base station. When it is sent to the line, the local station does not receive the radio wave from the mobile station, and the incoming electric field information from the lower radio base station is L or H, the control logic circuit does not generate the switching control signal, which causes Then, the reception output from the lower radio base station and the incoming electric field information L or H
Is achieved by a mobile radio base station system characterized by being transmitted to a receiving line to a higher radio base station, and each radio base station is equipped with simplex control means, the simplex control means includes control logic. The switching control signal from the circuit 32, the incoming electric field information from the lower radio base station, and the press talk signal from the center are input, and the radio base station in the simplex transmission operation from the center. When the switching control signal and the incoming electric field information L from the lower radio base station are input, the simplex control means holds the switching control signal for a predetermined time, during which the transmitter of its own station is set to the transmittable state and When the press talk signal from the center is input within the above specified time without disconnecting the transmission line to the wireless base station, the switching control signal is held between the pre-talk signals and sent from the center. The speech signal is sent to the transmitter of the own station, and when the switching control signal from the control logic circuit 32 is cut off and the incoming electric field information from the lower radio base station becomes H, the transmission to the lower radio base station is started immediately. When the line is connected and the transmitter of its own station is cut off from the transmittable state, and each radio base station is equipped with a recovery control means, it is sent to the lower radio base station by the switching control signal from the control logic circuit. The talk line is cut off, the transmitter is not activated, and the transmission signal from the center is transmitted from the transmitter to the mobile station.

[Action]

The present invention provides incoming electric field information (binary information) corresponding to the incoming electric field level extracted from the receiver of the own station in the control logic circuit of the own station and incoming electric field information from the lower radio base station input through the receiving line. To compare.

If the comparison result indicates that the incoming electric field information of the own station is better or the same as the incoming electric field information of the lower radio base station, the incoming electric field information of the own station and the reception output are sent to the upper radio base station via the receiving line. Send out. However, when the incoming electric field information of the lower radio base station is better, the received output from the lower radio base station and the incoming electric field information H added in the own station are sent to the upper radio base station via the receiving line.

When the incoming electric field information from both the own station and the lower radio base station is L, the reception output of the own station and the incoming electric field information L are sent to the upper radio base station, and the own station does not receive the radio wave from the mobile station. In this case, if there is a reception output from the lower radio base station, this reception output is sent to the upper radio base station via the reception line together with the incoming electric field information L or H from the lower radio base station.

That is, the center can always receive the information from the mobile station in the best S / N state by sequentially repeating the comparison between the own station and the incoming electric field information from the lower radio base station. Is.

On the other hand, when transmitting from the center to the mobile station by simplex method,
During the transition from the receiving state to the transmitting state, the switching control signal from the control logic circuit (the state where the incoming electric field information of the own station is better than or equal to the incoming electric field information from the lower radio base station) May disappear.

Therefore, the simplex control means is used to hold this switching control signal for a predetermined time to make the transmitter ready for transmission and disconnect the transmission line to the lower radio base station.

If the press talk signal from the center is input within the predetermined time, the switching control signal is further held while this signal is input, and during this period, the transmission signal is set in the ready state and the transmission signal is received at the best S / N ratio. The data is transmitted from the wireless base station to the mobile station.

In the case of the duplex method, there is no standby, so there is no need to hold the switching control signal, and the duplex control means is driven by the switching control signal from the control logic circuit to make the transmitter ready for transmission and Disconnect the talk line as above.

As a result, even if the mobile station moves from one location to another, the operation management center and the mobile station can always communicate in a good S / N state.

〔Example〕

3 is a block diagram of an embodiment of the present invention (single communication system), FIG. 4 is an example of a signal transmitter / signal receiver block diagram in FIG. 3, and FIG. 5 is control in FIG. An example of a logic circuit block diagram, FIG. 6 is an operation explanatory diagram of FIG. 5, FIG. 7 is an example of a retarder block diagram in FIG. 3, FIG. 8 is an operation explanatory diagram of FIG. The figure shows a block diagram (replica communication) of another embodiment of the present invention.

The relays RL ₁ and RL _{2 in} FIG. 5 correspond to RL _1b and RL _2b in the case of the radio base station b in FIG. 3, and correspond to RL _1n and RL _2n in the case of the radio base station n. To do.

The signal receiver 31b, the control logic circuit 32b, the signal transmitter 33b, and the relays RL _1b and RL _2b shown in FIG. 3 are the components of the control logic means 3 shown in FIG. 1, a distributor 41b, and a retarder 42b. The signal receiver 43b and the relays RL _3b and RL _4b are components of the simplex control means 4 shown in FIG.

Further, the distributor 51b, the signal receiver 52b, and the contact shown in FIG.
r _1b2 and r _1b3 indicate the components of the replay control means 5 of FIG.

First, as shown in FIG. 3, the center 1 and each radio base station
The transmission lines 11 and 12 are connected to a, b, ... N in common, and the configuration of each radio base station is the same except for the highest and lowest radio base stations. The wireless base station a lacks a signal transmitter, and the wireless base station n lacks a signal receiver. Hereinafter, the reception operation of the radio base station will be described with reference to FIGS. 3 to 8.

(1) Receiving operation Now, suppose that the radio base station b and the radio base station n simultaneously receive radio waves from the mobile station 13.

Receiver of wireless base station b (hereinafter abbreviated as own base station)
21b sends the incoming electric field level, the squelch operation information, and the reception output through the corresponding signal lines 3b, 2b, 1b. Among them, the incoming electric field level and the squelch operation information are controlled by the control logic circuit 32b.
Add to The squelch operation information is H if the squelch circuit (not shown) in the receiver operates and L if it does not operate.

Further, as will be described later, the control logic circuit 32b receives incoming electric field information (the incoming electric field level is higher than a threshold value) from a lower radio base station (hereinafter, abbreviated as lower base station) via a signal receiver 31b. Information indicating whether it is low or low) is also input through the receiving line 12.

Now, the comparator 321 in the control logic circuit shown in FIG. 5 compares whether the incoming electric field level of its own base station b is higher or lower than a predetermined threshold value. The incoming electric field information of L is output. The threshold value is set to a level higher than the squelch operating point.

Now, when both the squelch operation information and the incoming electric field information of the own base station are H and the incoming electric field information of the lower base station is H or L as shown in FIG. AND in
H from gate 323 relays through OR gates 327 and 328 RL
Drive ₁ , RL ₂ .

As a result, the receiving line is switched to the receiver of the own base station by the relay RL ₁ , so that the reception output of the own base station is transmitted and the activation signal (for example, ground) is sent by the relay RL _2.
Is added to the signal transmitter 33b.

Therefore, a signal of, for example, 3 KHz from the signal transmitter 311 in the signal transmitter of FIG. 4 is sent to the signal receiver of the upper base station a via the receiving line together with the reception output from the receiver. The incoming electric field information indicates that the incoming electric field level is equal to or higher than the threshold when 3 KHz is transmitted and equal to or lower than the threshold when not transmitting.

The incoming electric field information of H from the above lower base station is the fourth
As shown on the left side of the figure, the signal is sent to the control logic circuit via the receiving line, the band pass filter 331 and the detector 332 in the signal receiver of the own base station.

However, when the squelch operation information of the own base station is H and the incoming electric field information is L as shown in item 2 of FIG. 6, when the incoming electric field information of the lower base station is H, the AND gate in FIG. Since the relays 323 and 326 are off, the relay RL ₁ is not driven and the receiving line remains connected to the lower base station.

On the other hand, the incoming electric field information of H from the lower base station is OR gated.
Since the relay RL ₂ is driven via 328, the activation signal is given to the signal transmitter 36b of the own base station, and the voice signal of the lower base station and the incoming electric field information of H are sent to the upper base station a.

Further, as shown in item (1) of FIG. 6, when the incoming electric field information of both the own base station and the subordinate base station is L, the output of the AND gate 326 becomes H, so the relay RL ₁ is driven by this H. To connect the receiving line to the receiver 21b of the own base station. This allows
The reception output of the receiver 21b is sent to the upper base station via the low pass filter 311 of FIG.

However, since the relay RL _{2 in} FIG. 5 is not driven, the activation signal is not applied to the signal transmitter 33b in FIG. 3, and the incoming electric field information of L is sent.

In addition, as shown in FIG. 6 (5) and (6), when the radio wave from the mobile station is not received at the own base station (squelch operation information is L), the output of the AND gates 323 and 324 in FIG. Becomes L, the relays RL ₁ and RL ₂ do not operate, and the reception output of the lower base station and the incoming electric field information are relayed to the upper base station.

(2) Transmission Operation (Simplex Method) Next, as shown in FIG. 3, the delay device 42b of the radio base station b is
Is a switching control signal (S
/ N determination information) and the incoming electric field information of the lower base station from the signal receiver 31b are added.

As shown in FIG. 7, the retarder 42b includes a monostable multivibrator 422,424, a flip-flop 427, and an OR gate 423,4.
25, AND gates 421 and 426 with partially inverted inputs. The monostable multivibrator (hereinafter abbreviated as MM) 422 is for delay time, and MM424 is for reset pulse generation.

Now, the base station is H and the lower base station is L as incoming electric field information.
The operation will be described when the press talk signal is not input from the center (see FIG. 8A).

As shown in FIG. 8 (a)-, the control logic circuit 32b
To H and the signal receivers 31b to 31L are input to the retarder 42b, the AND gate 421 with partially inverted input is turned off and the AND gate 426 with partially inverted input is turned on. Therefore, the Q terminal of the flip-flop (hereinafter abbreviated as FF) 427 becomes H by the H from the control logic circuit 32b (eighth).
Fig. (A)-).

After that, the MM422 rises and outputs H at the fall of the output of the control logic circuit 32b, but since the press talk signal is not input even after the elapse of the time T, it falls back to L, but this fall. Then, the reset pulse is sent from MM424 to FF427. This resets the FF (Fig. 8 (a)-
~reference).

That is, while the FF 427 is H, the S / N determination information that the S / N is better than that of the lower base station is held and the relay RL _{3 in} the radio base station b in FIG. ₃ is driven.

Therefore, since the contact r _3b1, r _3b2 of this relay is dotted state with the transmitter 22b is transmittable state, press-to-talk signal and As transmission signal is not transmitted transmission line to the lower base station 11 Turn off.

Next, as shown in FIG. 8 (b), a case will be described in which the incoming electric field information is the own base station H and the lower base station L, and the press talk signal is input from the center.

As shown on the left side of FIG. 8 (b), the Q terminal of FF427 becomes H at the rising edge of the output of the control logic circuit, and H is output from MM422 at the falling edge of the output of the control logic circuit. Thus, the contact r _3b1 relay RL _3b is driven, r _3b2 is dotted manner (Figure 8 (b) - ,,, reference).

On the other hand, the center 1 in FIG. 3 turns on the call switch SW ₂ to send the output of the transmitter 14, mixes the sending signal from the microphone with the amplifier 13, and sends it through the sending line 11. In the radio base station b, the signal receiver 43b receives the signal via the distributor 41b and the output of the oscillator 14 is detected. Then, this is used as a press talk signal to the transmitter 22b via the _retarder 42b and the contact r _3b2. Since it is added, this is the starting state.

Here, in the retarder 42b, since the press talk signal from the center is input while the output of the MM422 is H as shown in FIG. 8 (b)-, the falling point applied to the MM424 is delayed,
As shown in FIG. 8 (b)-, the operation of the relay RL _3b is maintained until the press talk signal is disconnected.

Therefore, the mobile station 1 transmits the transmission signal via the signal receiver 43b and the transmitter 22b, that is, via the radio base station b having a good reception S / N.
Dispatched to 3.

At the center 1, turn on the call switch SW ₂ , switch S
When W _{1 is set} to the dotted line state, the transmitter 15 operates and the broadcast signal is sent to the wireless base station via the transmission line. For example, in the radio base station, the signal receiver 43b receives this signal and drives the relay RL _4b to _bring the contacts r _4b2 , r _4b1 into the state of the dotted line, so that the transmission line is extended to the lower base station. At the same time, the transmitter is activated, so that simultaneous transmission is possible.

Further, as shown in FIG. 8 (c), when the output of the control logic circuit changes from H to L during reception at the own base station and H is input from the lower base station, the output of FF422 immediately changes to L. The holding operation of the retarder 42b is released, and the S / N advantage of the own base station is switched to the lower base station S / N advantage state (Fig. 8 (c)).
---).

(3) Transmission operation (return method) In the case of the return method, if the own base station has S / N superiority, the center can immediately send, so a delay device is not required, but disconnection of the transmission line to the lower base station and The contacts r _1b2 , r _1b3 for making the transmitter ready for transmission are turned on / off by the relay RL _{1b as} shown in FIG.

That is, when the control logic circuit 32b outputs H as described above, the relay RL _1b is driven by this H and the contacts r _1b1 , r
_1b2 and r _1b3 become like the dotted line. As a result, the reception output from the receiver is transmitted to the reception line, and the transmission signal from the center is transmitted from the transmitter to the mobile station via the signal receiver. Also, the transmission line is disconnected to the lower base station at the contact point r _1b2 .

That is, the base station is automatically selected as the best station according to the change in the position of the mobile station, so the operation management center and the mobile station can always communicate in good S / N condition. Becomes

〔The invention's effect〕

As described in detail above, according to the present invention, there is an effect that the center and the mobile station can always communicate in a good S / N state.

[Brief description of drawings]

FIG. 1 is a block diagram of the principle of the present invention (single communication system), FIG. 2 is a block diagram of the principle of the present invention (recovery system), FIG. 3 is a block diagram of an embodiment of the present invention, and FIG. 4 is FIG. FIG. 5 is an example of a block diagram of the control logic circuit in FIG. 3, FIG. 6 is an operation explanatory diagram of FIG. 5, and FIG. An example of a block diagram of the retarder in the figure, FIG. 8 is an operation explanatory diagram of FIG. 7, FIG. 9 is a block diagram of another embodiment of the present invention, and FIG. 10 is a block diagram of a conventional example. . In the figure, 3 is a control logic means, 4 is a simplex control means, 5 is a duplex control means, 11 is a transmission line, 12 is a reception line, 21 is a receiver, 22 is a transmitter, and RL ₁ is a line switching part. Show.

Claims (3)

(57) [Claims] 1. A transmission line between the center and a plurality of wireless base stations
In a mobile radio base station system in which the center and the mobile station communicate with each other via the radio base station, the receiver 21 receives the radio wave from the mobile station. In addition to the reception output, at least the incoming electric field information is output, and at least the incoming electric field information of the own station and the incoming electric field information from the lower radio base station via the receiving line are input to the control logic circuit 32 in the wireless base station, Regardless of whether the incoming electric field information of the local station is H and the incoming electric field information from the lower radio base station is L or H, the control logic circuit generates a switching control signal and is controlled by the switching control signal. The connection of the receiving line from the base station is cut off, and the reception output from the receiver 21 of the own station and the incoming electric field information H from the own station are sent to the receiving line to the upper radio base station, and the incoming call of the own station is received. Electric field information And when the incoming electric field information from the lower radio base station is H, the control logic circuit does not generate the switching control signal, whereby the reception output from the lower radio base station via the receiving line and the incoming call at the own station are generated in the own station. Electric field information H
Is sent to the receiving line to the upper radio base station, and when the incoming electric field information from both the own station and the lower radio base station is L, the control logic circuit generates a switching control signal, which causes the lower radio base station in the own station. The receiving line from the station is cut off, the reception output of the own station and the incoming electric field information L are sent to the receiving line to the upper radio base station, the own station does not receive the radio wave from the mobile station, and the lower radio base station. When the incoming electric field information from L is H or H, the control logic circuit does not generate the switching control signal, so that the reception output from the lower radio base station and the incoming electric field information L or H are in the local station. A mobile radio base station system characterized in that the mobile radio base station system is transmitted to a receiving line to the mobile phone. 2. When each radio base station is provided with simplex control means, the simplex control means has a switching control signal from the control logic circuit 32, incoming electric field information from a lower radio base station, and a press from the center. The talk signal is input, and the simplex control means holds the switching control signal for a predetermined time when the switching control signal and the incoming electric field information L from the lower radio base station are input, and during that time, the simplex control means When the transmitter is set to the transmittable state, the transmission line to the lower radio base station is disconnected, and the press talk signal from the center is input within the above-mentioned predetermined time, the switching control signal is held between the press talk signals and the center is held. To the transmitter of its own station, and when the switching control signal from the control logic circuit 32 is cut off after the input and the incoming electric field information from the lower radio base station becomes H, it is immediately sent to the lower radio base station. of 2. The mobile radio base station system according to claim 1, wherein a transmission line is connected and the transmission enabled state of the transmitter of the own station is cut off. 3. When each radio base station is provided with a duplication control means, the transmission control line from the control logic circuit disconnects the transmission line to the lower radio base station, the transmitter is not activated, and the center 2. The mobile radio base station system according to claim 1, wherein the transmitter signal is transmitted from the transmitter to the mobile station.