JP2000102076A - Selective calling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a practical selective calling device capable of receiving voice signals transmitted from radio equipment to which the selective calling device is not added and preventing the generation of a malfunction and the interruption of communication. SOLUTION: In terms of a principle, control is performed to a state capable of receiving the voice signals at the time of not receiving selection signals and the control is performed to a state incapable of receiving the voice signals when the selection signal is received and it does not match with a present station number. Further, the operation state of this selective calling device is classified into a standby state 1, a bare communication state 2, a selective communication state 3 and a busy state 4 and the control is performed so as not to shift to the busy state 4 even at the time of receiving the non-matching selection signal in both communication states of the bare communication state 2 and the selective calling state 3. Thus, the practical selective calling device for suppressing the generation of the malfunction and preventing the interruption of the communication is realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a selective calling apparatus which is attached to a radio and selects a communication partner station using a selection signal.

[0002]

2. Description of the Related Art When a large number of users communicate within the same area using radio waves of a single radio frequency, a problem of interference occurs. To cope with this, users are classified by organization, by organization, for example, by assigning tone frequencies by company, by cutting the received output signal by a tone squelch circuit, or by assigning a digital code instead of the tone frequency, receiving By cutting the output signal with a digital squelch circuit, the interference problem is reduced. But,
In the same organization, there is still an interference problem, and in order to cope with this, a selective calling device that controls a reception output signal by a selection signal added to the head of a voice signal and transmitted has been put to practical use. Normally, a wireless device does not have a numeric keypad or a display of required digits, and cannot perform a call operation that requires setting the number of the called party, but since a microcomputer and a modem are built in, it is necessary to add a selective calling device This can be achieved simply by changing the microcomputer program. For this reason, there are a selective calling device that can perform a calling operation and a selective calling device that cannot be called and can only be called.

FIG. 2 shows the state transition of this conventional selective calling device.
And its operation will be described. In the operation state of the conventional selective calling device, it is classified into a non-selection state 5 and a selected call state 3,
In the non-selection state 5, the reception output signal is disconnected, and in the selection communication state 3, the reception output signal is controlled by the squelch circuit. Here, the squelch circuit is a general term for a combination of a noise squelch circuit, a tone squelch circuit, and a digital squelch circuit. In the case of a combination of a noise squelch circuit and a tone squelch circuit, there is a case of a combination of a noise squelch circuit and a digital squelch circuit. Hereinafter, the same is applied. When the selective calling device receives the selection signal in the non-selection state 5, the selective call device transits to the selective call state 3 through the arrow 531. On the other hand, in the selective call state 3, the call holding time is exceeded and the arrow 351 is displayed. Then, the state transits to the non-selection state 5. The call holding time is set slightly longer than the time when the reception output signal is expected to be interrupted due to fading or the like. In the selective calling device that can perform the calling operation, the calling operation causes the non-selected state 5 to pass through the arrow 532,
The state transits to the selected call state 3, and changes to the non-selected state 5 through the arrow 352 from the selected call state 3 by a call end operation.

[0004]

SUMMARY OF THE INVENTION An audio signal transmitted from a radio without a selective calling device (hereinafter referred to as a naked radio), that is, a radio which does not transmit a selection signal,
It cannot be received by a wireless device to which a conventional selective calling device is added. Therefore, when a user of an organization already using a bare radio is to add a selective calling device, it is necessary to add a selective calling device to all the radios at the same time, the initial cost is high, and further switching work is required. There was a problem of concentration. It has been desired that such a problem be solved so that a radio device provided with a selective calling device can also receive a voice signal transmitted from a naked radio device. In principle, in a radio equipped with a selective calling device, if a selection signal cannot be received, or if a selection signal is received and matches the number, the received voice signal is controlled by a squelch circuit to control the received voice. Can be output, and if the selection signal is received and does not match the number, control may be performed so that the received voice signal is disconnected (output is prohibited). In order to realize such control, in the selective calling device, for example, a selection signal is placed at the beginning of a voice signal,
At the end, a call termination signal is added and transmitted. When the selective calling device receives this, the received output signal is controlled by the squelch circuit when the selected signal matches, the received output is cut off when the selected signal does not match, and the same signal as the bare radio is returned by the end signal. What is necessary is to control.

However, in order to put this into practical use, there are the following problems (1) to (4) that must be solved. (1) When the notification signal transmission distance is shorter than the voice signal transmission distance, the selection signal cannot be received due to a weak reception electric field, but when the voice signal can be received, the radio device in a naked call state This is the same as the state where the signal transmitted from is received, which causes a problem that the signal is received by the radio device not selected. (2) When transmitting from the wireless device A to the wireless device B and immediately before the end of the transmission, if the quick B starts the transmission, the selection signal transmitted by the B first and the A by the last Due to the collision of the selection signals to be transmitted, the mutual selection signals of A and B cannot be received, and the radio equipment other than A and B can receive either of the selection signals or cannot receive both of them. Occurs. (3) For example, it is assumed that the radios A, B, C, and D are arranged in a straight line, and the areas where A and B exist, and C and D
It is supposed that the area where is present is appropriately separated, and that a bare radio can cause coexistence due to over-reach, but it can coexist due to the weakening and eroding effect of radio waves. Here, as A and B are talking without adding a selection signal, as in the case of a bare radio, D issues a signal for selecting C, and the selection signal transmitted by C in response to this is B. When received, the selection signals do not match, so that B is in a busy state and the call with A is interrupted. (4) It is assumed that the radios A, B, C, and D exist as in (3) above. Here, when A selects B and talks between A and B, and C sends a signal to select D, if this is received by B, the selection signal does not match. Causes a problem that A cannot be received.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and enables a communication between a wireless device without a selective calling device and a wireless device with a selective calling device to coexist. It is another object of the present invention to provide an extremely practical selective calling device that prevents malfunction and interruption of a call.

[0007]

According to the present invention, in order to achieve the above object, the selective calling apparatus of the present invention roughly divides an operating state into a talking state and a non-talking state. , A selective call state (3) in which a call is made using a selection signal, and a naked call state (2) in which a call is made without using a selection signal. Also, regarding the non-call state,
A standby state (1) in which a signal is not transmitted / received, which means a signal waiting state; and a state in which a selection number different from the selection number assigned to the own station is received in the standby state, and another station talks. It is classified into a busy state (4) (conventional non-selection state) which means a middle state.
As described above, while being classified into at least four operation states, and receiving a selection number different from the selection number assigned to the own station in both the call state of the selected call state and the naked call state, the state is changed to the busy state. The control is performed so as to prohibit the transition.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a state transition diagram showing the operation of one embodiment of the present invention. As shown in FIG. 1, the operation states of the selective calling device are classified into a standby state 1, a naked call state 2, a selected call state 3, and a busy state 4. The state transition is represented by an arrow. The solid line indicates a basic state transition, and the dotted line indicates a state transition that can be selected due to operating conditions or hardware restrictions. In the standby state 1, the naked call state 2, and the selected call state 3, the call is received and the output signal is controlled by the squelch circuit.
In the busy state 4, control is performed to cut off the reception output signal.

(No-Speech Timer) The no-speech timer indicates that the arrow 211, 311, 4, or 4, regardless of the state, when the time of no transmission or reception exceeds a predetermined time.
11 is a timer for shifting to a standby state. Here, the incoming call means a state in which the squelch circuit outputs an audio output signal. That is, the incoming call is a busy state 4
Otherwise, the voice output signal is output. In the busy state 4, the voice output signal is output if the selective calling device does not cut off the voice output signal. Here, the predetermined time is the longest time from when saying "please" to the other party answering during a press talk call, so that it can be selected according to operating conditions,
For example, it is set to 10 seconds.

(Transmission Operation) When the transmission operation is performed in the standby state 1, the transmission can be performed after transitioning to the naked call state by the arrow 121. When transmitting in the naked call state 2, the selection signal is not transmitted. In the selected call state 3, the selection signal can be added to the head of the audio signal, selected according to operating conditions, and the selection signal can be added to the end of the audio signal. On the other hand, busy state 4
In this case, whether or not transmission can be performed by transiting to the naked call state 2 through the arrow 421 or transmission is prohibited is selected according to the operating conditions.

(Transition to Naked Talk State) When one of the radios starts a naked call and receives the call and joins the call with the radio with the selective calling device, it usually responds. Therefore, the transmission operation is performed, but there may be a case where the reception is only performed. For this reason, it is convenient to transition from the standby state 1 to the naked call state 2 by the arrow 121 in addition to the transmission operation by the naked call operation. Normally, there is no dedicated switch for naked call operation, so an off-hook switch that works, for example, by lifting the microphone, may be used.

(Paging Operation) In the selective calling device capable of performing the paging operation, in the standby state 1, the paging operation can transit to the selected call state 3 through the arrow 132 by the paging operation. Similarly, in the naked call state 2 or the busy state 4, a transition can be made to the selected call state 3 through the arrow 232 or 432 by a call operation. However, whether to prohibit or permit the call operation is selected according to operating conditions. In a selective calling device that cannot perform a paging operation, a selection signal cannot be selected by an operation.
The called number, that is, the number assigned to the own station is transmitted.

(Initial Operation) By turning on the power or switching the channel, a transition is made from the start 61 to the standby state 1 or from the start 62 to the busy state 4. Here, standby state 1
Or the transition to the busy state 4 is selected according to the operating conditions. That is, when the state transitions to the standby state 1, even if it has not been selected, a call can be received. However, even if it is not actually in a busy state, if it does not wait for the time of the no-call timer, it may not be possible to receive the signal. Set the timer shorter than the normal busy state time, for example, 1
By setting the time to seconds, the function can be set to an intermediate function from the case of transition to the standby state 1.

(Detection of Selection Signal) The selection signal includes a bit synchronization signal, a frame synchronization signal, a user code, a control code,
The error detection code is configured in the order of the selection code and the error detection code. For error correction, the error detection code from the user code is subjected to Hagerberger coding, and the subcarrier is MSK-modulated and transmitted.
The bit synchronization signal is a code of several tens of bits that repeats 0 and 1. The frame synchronization signal is an M-sequence pseudo random code. The user code is a code assigned to each user. The control code classifies the attribute of the code, and here is a code indicating selection. The selection code is an individual number or a group number assigned to the wireless device. When the selection signals match, the frame synchronization is detected, no error is detected, and the control code and the selection code match. The case where the selection signals do not match is not the case where the selection signals do not simply match, but the case where frame synchronization is detected and no error is detected, the user code and the control code match, and the selection signals do not match. When the selection signals match, in any state,
A transition is made to the selected call state 3 by the arrows 131, 231, and 431. In the case where the selection signals do not match, the transition to the busy state 4 is made only from the standby state 1 by the arrow 141, and from both the naked talk state 2 and the selected talk state 3 the busy state 4 The transition to is prohibited.

(Reset) A reset key is added according to operating conditions in addition to the numeric keypad, and a reset signal is transmitted by a reset operation. The reset signal is similar to the selection signal, and is the same except that the control code is a code indicating reset. When a reset operation is performed or a reset signal is received, arrows 212 and 31 are displayed in any state.
A transition is made to the standby state by 2, 412. Thus, the standby state 1 can be forcibly set without waiting for the elapse of the no-call timer, and the non-selected party can be set to the busy state 4 by the selection signal.

As described above, by configuring the selective calling device, the above problem (1) can be solved by recognizing that if the signal can be received even once, it can be realized that the selective signal can be effectively received. Communication distance can be lengthened. Regarding the problem (2), since the same state can be maintained as long as the no-communication time is not exceeded, there is no problem even if the selection signal cannot be received from time to time. Further, regarding the problem (3), from the bare call state, the state shifts to the standby state when the no-talk time is exceeded, and when the received selection signals match, the state changes to the selected call state. Even when the selection signals do not match, the state does not transit to the busy state, so that the naked call state can be maintained. Further, regarding the problem (4),
From the selected call state, a transition is made to the standby state when the non-talk time is exceeded. However, even if the received selection signals do not match, the state does not change to the busy state, so that the selected call state can be maintained.

[0017]

As described above, according to the present invention, it is possible to call a wireless device with a selective calling device from a naked wireless device without a selective calling device. In addition, even a wireless device to which a selective calling device that cannot perform a calling operation is added can make a call using a naked call.
Further, it is possible to realize an extremely practical selective calling device that prevents occurrence of malfunction and interruption of communication.

[Brief description of the drawings]

FIG. 1 is a state transition diagram showing one embodiment of the present invention.

FIG. 2 is a state transition diagram showing an example of a conventional selective calling device.

[Explanation of symbols]

1: Standby state, 2: Naked call state, 3: Selected call state, 4: Busy state, 5: Non-selected state, 61-6
3: Start.

Claims (4)

[Claims] 1. A selective calling device attached to a radio device for selecting a communication partner station using a selection signal, said selective calling device comprising: a selected call state in which a call is made using said selection signal; At least four of a naked call state in which a call is made without using a telephone, a standby state in which a signal is on standby, and a busy state in which another station is in a call.
In the standby state, when a selection number different from the selection number of the own station is received, control is performed so as to transit to the busy state. A selective calling device comprising control means for controlling so as to prohibit the transition to the busy state even when a selection number different from the selection number of the station is received. 2. The selective calling device according to claim 1, further comprising: first detection means for detecting that a transmission operation or a naked call operation has been performed; and second detection means for detecting the presence or absence of a call. In the standby state, when the first detection means detects that a transmission operation or a naked call operation has been performed, control is performed so as to transition to the naked call state, and a selection signal from another station is received. When the received selection signal matches the selection number of the own station, control is made so as to transit to the selected call state. In the selected call state, the naked call state, and the busy state, the second detection means performs no call. When the period is detected for a predetermined time or more, control is performed so as to transit to the standby state. In the naked call state and the busy state, a selection signal from another station is received, and the received selection signal is automatically transmitted. Selection numbers and if they match of the selective call device characterized by comprising a control means for controlling to transition to the selected communication state. 3. The selective calling device according to claim 2, wherein the control unit controls output of a received voice signal in the selected call state, the naked call state, and the standby state, and receives the received voice signal in the busy state. A selective calling device comprising means for controlling output of a signal to be prohibited. 4. The selective calling device according to claim 3, further comprising means for inhibiting the transmission operation of the wireless device in the busy state.