JPS61173535A - Radio communication system - Google Patents

Abstract

PURPOSE:To save electric power and to reduce a transmitting device in size by synchronizing the transmitting device with plural receiving devices on the basis of the time data of a reference timer circuit provided to the transmitting device and powering off the receiving device except at the communication allotted time of selective call data. CONSTITUTION:A BCH encoding circuit 2D performs the abbreviated flange encoding of input data and supplies the result to an FSK encoder 2E and actual transmit data represented by signals of 1,200 and 2,400Hz is generated for transmitting data at 600Hz and supplied to a transmitter 2. Consequently, the transmit data is transmitted from all antennas 2H1-2Hk through a distributor 2G and received by antennas 41-4m of wrist watches of respective employees. When the call code of each employee is detected in this receive signal, the transistor of a power-source cutting off circuit is on without fail and receiving operation is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a wireless communication system between a base-side transmitting device and a plurality of terminal-side receiving devices equipped with a clock circuit and its time display section.

[Prior art]

In general, for example, when contacting someone who works in the same building using an office phone, it may be difficult to contact someone who is away from their desk. In such a case, it may be possible to communicate by radio or the like, but it is impractical to provide each employee with a transceiver etc. due to cost and other considerations.

On the other hand, pager services have been well known for a long time. In this system, subscribers are divided into, for example, 15 groups, each individual in each group is identified from a group designation signal and a selective call code, and an alarm sound is generated to call the subscriber.

[Problems with conventional technology]

However, in conventional systems, the circuit configuration for identifying each individual on the receiving side is complex, and the system must always be ready for reception, which consumes a large amount of power, and therefore requires the use of relatively large batteries. [Objective of the Invention] It is a simple circuit and requires less power consumption, so it is easy to miniaturize the receiving device, and it is also capable of displaying messages. [Summary of the Invention] A terminal having a highly accurate transmitting device on the base side that transmits a signal consisting of selective call data and message data. A synchronization operation based on the time data by the reference clock circuit is performed for a plurality of receiving devices on the side at the time of transmission, thereby particularly reducing power consumption.

〔Example〕

An embodiment in which the present invention is applied to an electronic wristwatch as a receiving device will be described below with reference to the drawings.

FIG. 1 is a system configuration diagram. In the figure, 11 to 1n are n keyboards installed on each floor of a building or factory, and are used to key in the number and message of the person you are trying to call. The output signal from ~1n is given to two transmission control units in the transmitting device 2, which constitutes a base station installed only at one location within the company.The above numbers refer to all employees in groups 0 to 15.
Since the group is divided into 16 groups, it consists of a group hood and a hood indicating the employee's number within each group.

Accurate time data from the reference clock 2B is also given to the two transmission control units, and based on this time data, the two transmission control units select the receiving devices carried by each employee in the company, as will be described later. Equipped with electronic watches 61-6! The transmission operation is controlled while performing synchronous operation with each L and L.

The two transmission control units temporarily store the message data from the keyboards 11 to 1n in the memory 20 when there are many transmission requests, and when transmitting, the message data is sent by the above-mentioned number, that is, the call code, and the message data. The data is sent to the BOH encoding circuit 2D and converted into shortened 7-range code data. This shortened 7-range code data is further converted into IFS
K (IFRIIfQUENOY SH Engineering FT KI
CY engineering) is sent to encoder 2Ic and converted into data for actual transmission, transmitter 2? Antennas 2H1 to 2Hxk1. and transmitted at a frequency of 600 Hz.

In addition, in order to transmit data at 600 Hz, the FSX enhancer 2 has a frequency of 12, which is twice or four times that frequency.
The above transmission data expressing digital data is created by combining signals of 00 Hz and 24 Q Q Hz.

Next, the circuit configuration of the wristwatches 61 to 3n will be explained with reference to FIG. In the figure, 4 (41~4m) is for each wristwatch 31~
The receiving antennas are respectively installed in the 6ffl, and receive the 600Hz signal sent from the transmitter 2, that is, the 6ffl.
00 bit/sec of transmission data is received. Note that, as described above, since this data is BOH encoded, 8 redundant bits are added to the 8-bit data, resulting in a total of 16 bits of data.

The structure of the received data will be explained in more detail with reference to FIG. The data given to each group from the 0th group to the 15th group has the same configuration.The data in each group is assigned a reception timing of 1 second, so each group receives its data every 16 seconds. The timing will come. Note that the transmitting device 2 transmits the transmitted data to the reference clock 2.
Transmission from the 0th group starts when the time of B is exactly 00 seconds. Therefore, each wristwatch 61 to
6n becomes capable of synchronous operation.

As shown in Figure 5, at the beginning of each group, meaningless data for correcting the reception timing shift of 18 bits is sent, followed by bit synchronization data of 22 bits, and then 8 bits of bit synchronization data. Seven bits of synchronized data are sent. Then, 32 bits of call food data,
The configuration is such that 13 bits of free data and next message data are sent. The first 16 bits of the call hood data indicate the group hood, and the second 16 bits indicate the individual hood in each group.

Returning to FIG. 2, the signals received by antennas 41 to 4 are input to the receiver 5 where they are amplified and detected, and then fed to the IFSX decoder 6 where they are decoded and 1-bit synchronized. The 2400Hz signal of the synchronized circuit is the IF
The signal is supplied to the SX dehooder 6, 7, a frame synchronization circuit 7, and a timing generation section 9, which will be described later. The frame synchronization circuit 7 detects the frame synchronization data and provides the detection signal to the main component 9, which sends the timing signal I
Po.

' 1 , ' 2 r ' Generate P 3. This timing signal 1Po is synchronized with the last bit of the 7 frame synchronization bits, and Fl is synchronized with this 'I! o to 1
A signal generated every 6 pits, IF2 is a signal generated at the 16th bit from PQ, and F3 is a signal generated at the 32nd bit from A0.

The BOH demodulation circuit 8 receives a 7-rem synchronization signal FQ as described later.
Then, the paging data in the data from the FSK dehooder 6 is BOH-decoded and divided into 8-bit data, which is then sent to the paging food detection circuit 10 and the reception control section 11.
, is given to the memory control unit 12. Then, the call hood detection circuit 10 discriminates between group hoods and individual hoods in the call hood data, provides the discrimination result to the reception control section 11 and the memory control section 12, and also sends an alarm signal to the buzzer drive circuit in the clock circuit, which will be described later. Give as AL. Further, in the reception control unit 11, when the own group is not called from the above-mentioned determination result, that is, when it is not the reception allocation timing,
It sends a signal to the power cut-off circuit 16 for the receiver 5 to turn off the power, while on the other hand when its own group is being called.
Turn on the power cutoff circuit 13. Note that when a reception failure occurs, the power remains on, so in that case, the reception control section 11 sends a signal to the buzzer drive circuit to generate an alarm sound.

Furthermore, the reception control section 11 also performs an operation to correct the time measurement data of the clock circuit at this own reception allocation timing based on the frame synchronization signal and the group hood, so that it matches the time of the reference clock 2B in the transmission device 2. .

The memory control section 12 controls the writing of message data into the memory 14, and controls the writing operation to be stopped by a signal from the reception control section 11 when the storage of the message data is completed.

The message data written in the memory 14 is then sent to a display drive circuit within the clock circuit and displayed on the display section.

Note that the circuits 4 to 14 described above constitute a receiving device built into the wristwatch.

Next, to explain the clock circuit, as shown in FIG. It consists of a counting circuit 17 that obtains the clock data, a display control circuit 18 and a display drive circuit 19 that display the clock data, and a display section 20 that displays the clock data.
Alarm time memory 21 to be set - this memory 2
A coincidence circuit 22 inputs the 7th ram time from 1 to 1 and the above clock data and detects the coincidence.A coincidence detection signal from this coincidence circuit 22 is manually generated to generate a buzzer drive signal, and a buzzer (as shown) ), and a speaker 24 that emits a buzzer sound (alarm sound). Note that the 1200 Hz and 2400 Hz branch signals of the frequency dividing circuit 16 are also applied to the dehooder 6, the frame synchronization circuit 17, and the timing generation section 9 at 78, and are used to execute the FSK dehood and 7-rem synchronization operations.

Next, as shown in FIG.
1. The circuits such as the memory control unit 12 and the counting circuit 17 will be specifically explained. The BOH demodulation circuit 8 demodulates the data from the IFSX dehooder 6 in response to the input of the signal F1, and among the output call hood data, the group hood is sent to the latch 25 in the call hood detector 1o, and the individual hoods are sent to the latch 2.
6 respectively, and the message data is sent to the memory control unit 1.
2 to the memory 14 through the seventh gate 27.

Thus, the latches 25 and 26 receive the signal y2 or 7, respectively.
3 performs a latch operation. Further, the output of the latch 25 is applied to the coincidence circuit 28 and the A input terminal of the subtraction circuit 29 in the reception control section 11. The output of latch 26 is also applied to matching circuit 30.

On the other hand, the other end of the - number circuit 28 is input with the group hood of the employee carrying the wristwatch, which is preset in the call hood ROM (read only memory) 61. Individual food is entered. Therefore, the -number circuit 28.60 executes a match detection operation between the call hood transmitted from the transmitting device 2 and the call hood of the employee carrying the wristwatch, and each match detection signal is sent to the 7-nd gate 32. It will be done. The output of the 7nd gate 62 is applied to the set input terminal of the 7th lip-flop 66 in the memory control section 12, and is also applied to the 7nd gate 65 via the inverter 64 in the reception control section 11.
Furthermore, the alarm signal hr is applied to the buzzer drive circuit 23, respectively.

Is the set output signal of 7 lip 70 tube 33 a signal? 1 and a certain are input to the AND gate 27 and its opening/closing control is performed.

The call code from the ROM 51 is input to the B input terminal of the subtraction circuit 29, and the call code that is sent,
That is, a subtraction operation is performed with the contents of the latch 25. The data resulting from the subtraction is converted into sexagesimal data by the binary to sexagesimal conversion circuit 66, and is preset in the seconds and minutes counter 67 in the counting circuit 17. As a result, when the wristwatch is ahead or behind by seconds, the time can be adjusted within the range of +7 seconds to -8 seconds.

Further, the seconds data of the seconds/minutes counter 67 is converted into binary data by the sexagesimal to binary conversion circuit 3B, and the - number circuit 69 stores it in ROM! compared with the group code from 11,
The coincidence detection signal is then inputted to a digital game (40). A detection signal from a detection circuit 41 is further input to this AND gate 40, and the detection circuit 41 is connected to the branch circuit 16.
The value is approximately 0.03 seconds (3 seconds) by manually inputting the branch data from
/100 seconds), and this detects the passage of time for the first 18 pits of the data structure shown in FIG. and 7nd ° gate 40
17') Applied to the 7-button input terminal S of the output LJ7 lip 42.

The set output of this 7-lip 70-tube 42 is supplied to a power cutoff circuit 16 to control the power on and off.

A signal 73 is input to the other end of the seventh gate 35,
The output is then input to the OR gate 44. Further, the message data is manually inputted to the message end detection circuit 45, and the end of the message is detected from the end hood attached at the end of the message data. The detection signal is input to the off gate 44 and also causes the 7-lip 70 knob 33 to be reset. The output of the off gate 44 also resets the 7-lip 70-tub 42 mentioned above.

The output of the detection circuit 41 is also supplied to a timer 47 as a drive signal. This timer 47 is turned on during the 62-bit timer period, and its turn-on signal is sent to the signal detection circuit 4.
8. This signal detection circuit 48 is a circuit that detects whether or not the 7-rem synchronization signal PQ is generated while the above-mentioned ON operation signal ("1") is input, and when the signal 1o is not generated, one signal is emitted. The OR gate 44 generates a detection signal of
It is applied to the reset input terminal R of the 7rip 70 knob 42 through the 70p. Therefore, the 7 lip 70 knob 42 is reset,
That is, the power to the receiver 5 is turned off when frame synchronization cannot be achieved and reception is not possible.

The hour counter 46 in the clock counting circuit 17 is a circuit that counts the 'JP Yary signal from the seconds and minutes counter 67 to obtain hour data.

Note that when the frequency dividing circuit 16 receives its own call hood, it is forcibly set to approximately 97100 seconds (0.09 seconds) by the frame synchronization signal IFo included in the call hood, and synchronizes with the reference clock 2B. The time was corrected.

FIG. 4 shows the specific configuration of the power cutoff circuit 13.
As shown in the figure, it consists of a resistor R and a transistor TR. A set output signal from the 7-lip 70 tube 42 is manually supplied to the resistor R to the pace of the transistor TH, turning the transistor TR on and off. The emitter of the transistor TH is grounded, and the left end is connected to the receiver 5. The receiver 5 is supplied with the power supply voltage vDD from the battery, and the supply of the power supply voltage VDD is turned on according to the on/off state of the transistor TR.
It will be turned off.

Next, the operation of the above embodiment will be explained with reference to the waveform diagram shown in FIG. 5 together with the data structure.

When you want to contact a certain employee, enter the call hood from a nearby keyboard, for example 11 in Figure 1,
Next, message data such as "Call..." is input manually. These are then input to the two transmission controllers,
When the time data of the reference clock 2B reaches exactly 00 seconds, it is accepted and sent to the BOH encoding circuit 2D. However, when the t1 communication is busy, the above keyed data is temporarily stored in the memory 20 and later read out and transmitted.

Does the BOH encoding circuit 2D perform short plunge encoding on the input data? 8 encoder 2] I! 1600Hz
In order to transmit data at (600 bits/sea), actual transmission data expressing the data with signals of 1200 Hz to 2400 Hz is created and given to the transmitter 2y. Therefore, the transmission data is transmitted from all the antennas (2H1 to 2HK) by the distributor 2G and received by the antennas 41 to 4m of the wristwatches 31 to 6 degrees of each employee.

This received signal is input to the receiver 5 shown in FIG. This receiver 5 detects the period (1 second) once every 16 seconds for the group to which the employee belongs, and also during the period during which his own call hood is detected, which will be described later. As shown in FIG. 5, when the set output signal of the flip 70 knob 42 is "B", the transistor TR of the power cutoff circuit 16 is always on, is supplied with the battery voltage vDD, and performs the above-mentioned receiving operation. At other times, that is, except when a message is sent to itself, the transistor TR is turned off, and the receiver 5 is not supplied with the battery voltage vl)I). The FSK dehooder 6 bit-synchronizes the signal from the receiver 5 and outputs it as serial data to a frame synchronization circuit 7 and a BQH demodulation circuit 8.The frame synchronization circuit 7 converts the frame synchronization data of the serial data into serial data. The timing signal y is detected and sent to the timing generator 9.
□-75 is generated. In addition, the BOH demodulation circuit 8
It performs demodulation and sends its output to the call hood detection circuit 10, reception control section 11, and memory control section 12.

The call hood detection circuit 10 performs a comparison check between the sent call hood and the call code set for itself, and if the result shows that it is not being called, it sends a signal to the reception control unit 11. Power cutoff circuit 1
Turn off the power to the receiver 5 by turning off the
It also sends a signal to the memory control unit 12 to inhibit data writing to the memory 14.

On the other hand, when the employee is called, the power of the receiver 5 is turned on, an alarm sounds from the speaker 24 to notify the employee of the transmission, and the message data is written into the memory 14, and then displayed on the display 20. to be displayed for a certain period of time. Then, the reception control unit 11 completes the transmission of the message data.
At that time, the power to the receiver 5 is turned off.

On the other hand, the clock circuit constantly outputs clock time data through the counting operation of the counting circuit 17, and displays the current time on the display section 20. And the branch circuit 16 operates once every 16 seconds.
The time is matched with the reference clock 2B by the frame synchronization signal FQ, and any corrections below the second are made in black. Further, the second position correction is performed by detecting the displacement of the calling hood by the reception control section 11.

Next, to explain the operation of receiving a called food item in more detail, in the clock of the 0th group, the time measurement data is 0 minutes 0.
When the second reaches 0 seconds, the minute/second data of the minute force counter 67 is converted by the sexagesimal to binary conversion circuit 68 and is given to one end of the -number circuit 69, so the -number circuit 69 converts the other data. It detects the match between the call hood from the ROM 51 which is manually operated at the end and the above conversion data, and thereafter gives a match signal of ``1'' to the 7nd gate 40 and drives the timer 47 to start the ON operation. After that, the timer 47 starts outputting the ON operation signal of "BI" and is supplied to the signal detection circuit 48, and the 7-rem synchronization signal? 0 detection operation is started. And the output of the minute circuit 16 is about 3710
When the data corresponds to 0 seconds, that is, as shown in FIG. It detects this and outputs a detection signal of "P" and feeds it to the AND gate 40.
At this time, the output of 0 becomes “B” and N7 rip 70 lub 42
is set, and the set output signal becomes Bi. Therefore, the transistor TR in the power cutoff circuit 13 is turned on,
Power supply to the receiver 5 is started. Also, the quinary counter 4
6 starts to be driven.

When frame synchronization data is received approximately 6/100 seconds later and detected by the 7-rem synchronization circuit 7, first, the 7-rem synchronization signal 70 is output from the timing generator 9. This signal 11Q is then applied to the branch circuit 16, set to 67,100 seconds as already mentioned, synchronized with the reference clock 2B, and corrected to the nearest second. In this case, since the signal 7o is output, the output of the signal detection circuit 48 becomes "0"'. Therefore, the upper bit C group hood of the paging hood received at the 16th bit after the 7th frame synchronization signal 7o is output is latched by the latch 25 by the output of the timing signal IF2, and after another 16 bits, the paging hood is latched by the latch 25. Is the lower rank person (individual food) a timing signal? 3 is latched into the latch 26, and the ROM! 11
Compared to the call hood from. If both match, a match signal of "1" is generated, and 7 lip, 70 lip, 6
3 to open the AND gate 27. Therefore, when the signal 11 is output every 16 bits, the message data is written to the memory 14 every 16 bits. Also, an alarm sound is emitted from the time the coincidence signal "l" is output. When the message data transmission is completed, the end hood is detected by the message end detection circuit 45, and the blip 7
42 and 33 are both reset. The message data in the memory 14 is displayed on the display section 20 for a certain period of time. Also, the power to the receiver 5 is turned off. On the other hand, since the output of the AND gate 32 is "0" for clocks other than the designated one among the clocks in the "0m group 1", the signal F3
As a result, an output is obtained from the 7-nd gate 35, and the 7-rip prop 42 is reset. This allows the receiver 5
Power is immediately turned off to prevent unnecessary power consumption. In addition, in watches other than the 10'' group, the receiver does not operate because the matching circuit 69 does not output at 0 minutes and 0 seconds. It may happen that the reception timing signal of the 0'' group cannot be received. For example, if the clock is 5 seconds behind, the second and minute counters will become 0 minutes and 0 seconds.
Even if an output signal is obtained from the coincidence signal 69, since it is the fifth group receiving mode at that time, the group code data sent from the transmitting device is the fifth group data.Therefore, the output from the minus number circuit 28 is I can't get it. In such a case, the difference is calculated in the subtraction circuit 29 and added to the second and minute counters via the binary to sexagesimal conversion circuit 36, so that the next "0"'
At the group reception timing, you can receive reliably. Furthermore, as mentioned above, when the 7 rip 70 knob 42 is set to safe) and the power is turned on, the reception synchronization may be lost or the radio waves may not be received. If not, frame synchronization cannot be achieved, and the signal detection circuit 48 outputs a single signal of "B" and supplies it to the OR gate 44.
The knob 42 is reset. Therefore, the power to the receiver 5 is immediately turned off, preventing power loss.

In this way, the calls for the 0th group are transmitted once every 16 seconds and the above-described process is executed, and the same is true for the other groups 1 to 15.

Note that in the above embodiment, transmission was performed at a frequency of 600 bits/sea, but of course, this frequency is not limited to this and may be arbitrary. Furthermore, in the above embodiment, the power was turned on and off only for the receiver 5 among the circuits in the receiving device.
The power may be turned on and off for all circuits within the receiving device. Furthermore, the receiver is turned on only when entering the building.
A switch may be provided with a function to turn it off. Further, in the above embodiment, data is transmitted and received only when inside the pill, but it may be possible to transmit and receive data even when going outdoors. Furthermore, the receiving device is not limited to being built into a wristwatch, but may be built into a small electronic device carried by an individual, such as an electronic desktop calculator. Furthermore, although the message is sent to each individual, the same message may be sent to several people at the same time, or even to everyone. Furthermore, in the above embodiment, each receiving side has a hood and transmits on the same frequency for selection, but each receiving side is equipped with a function to detect different frequencies so that calls can be made individually. Good too. Furthermore, it is also possible to divide the subjects into a plurality of groups, each of which detects a different frequency, and to select individuals in each group using hoods. [Effects of the Invention] As explained above, the present invention is capable of selective calling. a transmitting device on the base side that transmits signals consisting of data and message data; and a plurality of receiving devices on the terminal side that have a clock circuit and its time display and a receiving circuit that receives signals from the transmitting device. A wireless communication system comprising: a reference clock circuit included in the transmitting device; and means for synchronizing operations between the transmitting device and a plurality of receiving devices based on time data of the reference clock circuit; Since this wireless communication system is comprised of a power off means for turning off the power of the receiving device except when communication is required for the selective call data of each φ transmitting device during communication under synchronized operation, the circuit is simple. This has the advantage that wireless communication can be performed with low power consumption, and that it is easy to downsize the receiving device. It also has the advantage of being able to display messages, allowing you to know what's going on right away.

[Brief explanation of the drawing]

Fig. 1 is a system configuration diagram of an embodiment in which the present invention is applied to an electronic wristwatch, Fig. 2 is a circuit diagram of the terminal side between the receiving device and the watch, and Fig. 3 is a detailed diagram of the call hood detection circuit 10, etc.
Circuit diagram, number 4! jgi is a specific circuit diagram of the power cutoff circuit 13, and FIG. 5 is a diagram showing the data structure of received data. 11~1n...keyboard, 2...transmitter%2A
...Transmission control unit, 2B...Reference clock, 2o...Memory, 2D...BOH encoding circuit, 2X...psx
Encoder, 2IP...transmitter, 2G...distributor,
2H1~2HK...Antenna! 11~3! a...
Electronic wristwatch, 4 (41-4m)...Antenna, 5...
・Receiver, 6... IFI9 decoder, 7... Frame synchronization circuit, 8... BOH demodulation circuit, 9... Timing generation section, 10... Call hood detection section, 11-.
- Reception control unit, 12... Memory control unit, 13... Power cutoff circuit, 14-... Memory, 15... Oscillator, 1
6-... Frequency dividing circuit, 17... Counting circuit, 18...
- Display control circuit, 19...Display drive circuit, 20...
Display unit, 26...buzzer drive circuit, 24...speaker.

Claims (1)

[Claims] A transmitting device on the base side that transmits a signal consisting of call data and message data, and a plurality of receiving devices on the terminal side that have a clock circuit and a time display thereof and a receiving circuit that receives signals from the transmitting device. A wireless communication system comprising: a reference clock circuit included in the transmitting device; and means for synchronizing operations between the transmitting device and a plurality of receiving devices based on time data of the reference clock circuit. and a power-off means for turning off the power of each receiving apparatus except when communication is allocated to the selective call data of each receiving apparatus during communication under synchronized operation.