This invention relates to a control apparatus for a call reminder in a paging system, and more particularly to, a paging control apparatus for reminding a user carrying a receiver in a case where a call signal for reminding the user is included in a radio signal transmitted from a paging station, etc.

In these years, a paging receiver having various functions has been proposed and put into a practical use in a tendency of adding multi-functions to the paging system.

A conventional paging receiver comprises a call reminder for periodically reminding a user carrying the receiver by using a short alerting call which continues until the user manually discontinues it, so that a call is definitely recognized by the user, for instance, as described in the U.S. Patent No. 4,701,759.

There is also known from EP-A-0 265 064 a paging device in which the alert tone pattern is variable dependent upon the detection on specific addresses received and matched to stored addresses by an address coincidence detection circuit.

However, the conventional paging receiver has disadvantages in that a period between an initial call and a reminder call is fixed in advance, and an actuating time duration of a call reminder is also fixed in advance. Accordingly, the same call reminding operation is carried out between an emergent call and an ordinary call. As a result, a call reminding is carried out even in an ordinary call having no necessity of the call reminding.

Accordingly, it is an object of the invention to provide a control apparatus for a call reminder in a paging system in which the form of a reminding call is changed according to the degree of an importance.

It is another object of the invention to provide a control apparatus for a call reminder in a paging system, by which the degree of an importance is transmitted from a caller to a callee.

It is a further object of the invention to provide a control apparatus for a call reminder in a paging system in which a reminding call is generated only when a caller requires it.

According to this invention, a control apparatus is defined by the appended claims.

This invention will be explained in more detail in conjunction with appended drawings, wherein:

• Fig. 1 is a block diagram showing a paging receiver including a control apparatus for a call reminder in a paging system in a preferred embodiment according to the invention,
• Fig. 2 is an explanatory diagram showing a received signal in the paging receiver,
• Figs. 3 and 4 are timing charts showing reminding time signals, and
• Fig. 5 is a flow chart showing a control flow in the control apparatus.

A control apparatus for a call reminder in a paging system in a preferred embodiment according to the invention will be explained.

Fig. 1 shows a paging receiver comprising the control apparatus of the preferred embodiment which includes a radio circuit 19 for amplifying and demodulating a radio signal received by an antenna 18, a waveform shaping circuit 20 for shaping a waveform of a demodulated signal supplied from the radio circuit 19, a decoder 21 for carrying out a below described operation, a quartz oscillator 22 for supplying clock signals to the decoder 21, etc. a PROM 23 for storing its own call signal (call number), an alert signal generating time T₁ (defined as "first time") and a selecting signal SL of call reminders including a speaker 26, a LED 27, a vibrator 28, etc. The speaker 26, LED 27, vibrator 28 is driven by an alert apparatus driver 90. The apparatus further comprises a RAM 24 having a memory region 24a for storing a reminding control signal XX (to be described later), an amplifying and driving circuit 25 for the call reminders, a reset button 29 connected to the decoder 21, a CPU 30 for controlling the display of message, a liquid crystal display (LCD) 31 for displaying the message, and a switch 32 for turning a power supply 33 on and off. In the decoder 21, a signal supplied from the waveform shaping circuit 20 is processed to carry out the comparison of a call signal, the detection and analysis of the reminding control signal XX, a periodical reminding control operation according to the detection and analysis thereof, a transfer control operation of the message to the CPU 30, etc.

Fig. 2 shows a format of a digital coded signal including the reminding control signal XX. The signal includes a preamble signal 34 for changing an intermittent operation to a continuous operation in the radio circuit 19, a synchronous signal 35 for the synchronism of the receiver with a received signal, a selecting call signal 36 which is compared with the call number stored in the PROM 23 in a state of the synchronism with the received signal, message 37 which is received subsequent to the selecting call signal 36 in a state of a coincidence between the selecting call signal and the call number, and the reminding control signal XX of a two digit signal 38. The signal 38 is inputted by a user in accordance with the degrees of the importance and emergency. The signal 38 may not be inputted when user does not require.

Fig. 3 shows four kinds of reminding time signals 45 to 48, one of which is selected by a content of the reminding control signal XX 38. Each of the reminding time signals 45 to 48 includes a common first time T₁ which is the alert signal generating time and a corresponding one of non-common second times T₂ which is a period between an initial call and a reminder call (T_2A, T_2B, T_2C, and T_2D), each of which is one period of the corresponding reminding time signal as listed below. In Fig. 3, "high" durations indicated by 45a, 46a, 47a and 48a provide a generating period of an initial call, and remaining "high" durations provide a generating period of a reminder call. The two bit signal "00", "01", "10" or "11" is designated in accordance with the degree of an importance or emergency. In a call having no necessity of a reminding call, this designation is not carried out. REMINDING CONTROL SIGNAL REMINDING TIME SIGNAL X X 0 0 45 0 1 46 1 0 47 1 1 48

Fig. 4 shows another set of reminding time signals 55 to 58, each of which includes a corresponding one of non-common first times T₁ (T_1A, T_1B, T_1C, and T_1D) and a common second time T₂ equal to one period thereof. The relations between the reminding time signals 55 to 58 and the reminding control signal XX 38 are listed below. In Fig. 4, "high" durations indicated by 55a, 56a, 57a and 58a provide a generating period of an initial call, and remaining "high" durations provide a generating period of a reminder call. A content of the signal 38 is designated in accordance with the degree of an importance or emergency. REMINDING CONTROL SIGNAL REMINDING TIME SIGNAL X X 0 0 55 0 1 56 1 0 57 1 1 58

Operation of the control apparatus in the preferred embodiment will be explained in Fig. 5.

When the signal as shown in Fig. 2 is transmitted from a paging station to a paging receiver, the signal is received by the antenna 18 of the paging receiver which is turned on by the switch 32, and amplified and demodulated in the radio circuit 19. The signal thus amplified and demodulated is shaped in its waveform in the waveform shaping circuit 20, and the waveform shaped signal is supplied to the decoder 21. Before receiving the signal, the radio circuit 19 is controlled to operate in an intermittent mode by the CPU 30. Then, the radio circuit 19 is controlled to operate in a continuous mode by receiving the preamble signal 34. When the paging receiver is synchronized with the received signal in accordance with the synchronous signal 35, the decoder 21 detects whether the signal supplied from the waveform shaping circuit 20 has a call signal identical to the call signal CD stored in the PROM 23 by referring to the selecting call signal 36 (step S1). When the identical call signal is detected, it is then detected whether the reminding control signal XX 38 is included therein (step S2).

In a case where no reminding control signal is detected, an ordinary calling alert operation is carried out (step S18). In this ordinary calling alert operation, the calling alert amplifying and driving circuit 25 is controlled to drive at least one call apparatus selected from the speaker 26, the LED 27, and the vibrator 28 in accordance with the selecting signal SL, by which a user carrying the paging receiver is alerted only one time. In this state, if the message 37 includes data to be displayed on the LCD 31, the data are transferred to the CPU 30 and displayed on the LCD 31.

In a case where the reminding control signal XX 38 is detected in the received signal (step S2), on the other hand, the reminding control signals XX 38 is written into the memory region 24a of the RAM 24, and a periodical reminding operation is carried out as explained below.

When the reminding control signals XX 38 is "00", a reminding time signal is set to have a "high" duration of the first time T₁ and a period of the second time T_2A as the reminding time signal 45 shown in Fig. 3 (steps S3 and S4). On the other hand, when the reminding control signal XX 38 is "01", "10", "11", respectively, the reminding time signals are set to have periods of the second times T_2B, T_2C and T_2D, respectively, relative to the fixed "high" duration of T₁ as the reminding time signals 46 to 48 shown in Fig. 3 (steps S5 to S9). The relations between the reminding time signals 45 to 48 and the reminding control signal XX 38 are as follows. REMINDING CONTROL SIGNAL 38 REMINDING TIME SIGNALS 45 TO 48 X X HIGH DURATION PERIOD 0 0 T₁ T_2A 0 1 T₁ T_2B 1 0 T₁ T_2C 1 1 T₁ T_2D

The reminding call is generated to remind the user for the periodical first time of T₁, after an internal timer is set to have a time-up period equivalent to a period selected from the periods T_2A, T_2B, T_2C and T_2D according to a content of the reminding control signal XX 38 (step S10).

Consequently, the reminding call is carried out for the first time T₁ by selecting one apparatus from the speaker 26, the LED 27, and the vibrator 28 according to the selecting signal SL stored in the PROM 23, while the internal timer times the second time T₂ selected from T_2A, T_2B, T_2C and T_2D. Then, the decoder 21 determines whether the reset button 29 is pressed on or not (step S13), and whether the internal timer finishes the time-up of the above set second time T₂ (step S14). In a case where the reset button 29 is not pressed on during the first time T₁, and the set second time T₂ is elapsed without the pressing-on of the reset button 29 (step S11), the decoder 21 controls the internal timer to be reset (step S12). Then, operation is returned to the step S10, wherein the second reminding call is carried out for the next first time T₁, while the internal timer is driven to time the next second time T₂. This reminding operation is repeated by non-limited times, unless the reset button 29 is pressed on by the user.

When the reset button 29 is pressed on by the user, the decoder 21 detects it to exit from a loop of the steps S10, S13, S11, S12, and S10, so that the periodical reminding call finishes to remind the user. At this time, the decoder 21 resets the internal timer (step S14), and the reminding call is controlled to stop, if the reminding operation continues (if "YES" is found at the step S15), while the reminding control signal XX 38 stored in the memory region 24a of the RAM 24 is erased instantly (step S17), if the reminding operation does not continue. Then, this operation is returned to the step S1.

During this operation, if the message 37 included in the received signal includes data to be displayed on the LCD 31, the CPU 30 receives the data which are then displayed on the LCD 31.

The reminding time signals 45 to 48 may be replaced by the reminding time signals 55 to 58 as shown in Fig. 4, wherein the second time T₂ is set to be a fixed period common to the reminding time signals 55 to 58, while the first time T₁ is changed to be T_1A, T_1B, T_1C, and T_1D according to a content of the reminding control signal XX 38 as follows. REMINDING CONTROL SIGNAL 38 REMINDING TIME SIGNALS 55 TO 58 X X ON PERIOD 0 0 T_1A T₂ 0 1 T_1B T₂ 1 0 T_1C T₂ 1 1 T_1D T₂

As described above, the degree of an importance is transmitted from a caller to a callee by changing a "high" duration of a reminding call, a period thereof, etc. Consequently, the following reminding modes are possible to be carried out.

• (1) An important message such as an appointment, a business information, etc. is supplied from a caller to a callee by use of a periodical reminding call, while an ordinary message which is not so important is supplied from the caller to the callee by use of an ordinary calling alert. Accordingly, the callee is not always to respond to the call by discriminating the important and ordinary messages, when the callee can not spare a time to do so due to the busiest state.
• (2) In the preferred embodiment, the first to fourth class emergencies can be classified by use of the reminding time signals having different "high" durations and periods as shown in Figs. 3 and 4.

Although the invention has been described with respect to specific embodiment for complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modification and alternative constructions that may occur to one skilled in the art which fairly fall within the basic teaching therein.