JPH036508B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a reception display system that receives and displays radio waves emitted from a receiving unit that emits radio waves unique to each location from a plurality of locations. The purpose of this is to improve the disadvantages of providing a reception function for each display unit, such as the decrease in S/N ratio due to unnecessary radio waves emitted between the reception function units. The purpose is to make it easier to determine the order of calls when the channels are lit.

When a transmitting unit is provided for each table in a cafeteria, etc., and a signal unique to that transmitting unit is emitted, for example, a signal consisting of M arrays of N modulation frequencies is received and displayed by a receiving unit, an extremely large number of signals are required. If the receiving unit is configured with one receiving unit capable of receiving channels, the receiving unit will be expensive, and the cost will be high if used in a place where the number of channels is small. Therefore, for example, if one receiving unit can identify every 8 channels and multiple such receiving units are installed, it can be applied to places with a large number of channels, and it can be used in places with a small number of channels. We can provide the most cost-effective reception and display system for your location. However, when multiple receiving units are installed in parallel, there is a problem in that the S/N ratio decreases due to unnecessary radio waves emitted from each receiving unit. Therefore, increasing the transmitting output of the transmitting unit is regulated by the Radio Law. There is a problem that the transmission output cannot be increased.

The present invention has been made in view of this point, and will be explained in detail below with reference to Examples.

In Figure 1, 1 ₁ and 1 ₂ are transmitting units;
It emits identifiable radio waves unique to each transmitting unit from multiple locations, and these radio waves are received by one receiving unit 2 and then transmitted to multiple display units 3 ₁ and 3 ₂ connected in parallel to this receiving unit 2. The channels are displayed on the display sections 4 ₁ and 4 ₂ of the display units 3 ₁ and 3 ₂ .
5 ₁ and 5 ₂ are channel installation parts, 6 ₁ and 6 ₂ are reset buttons, and 7 ₁ and 7 ₂ are display mode changeover switches.

FIG. 2 shows a circuit diagram of the transmitting units 1 ₁ and 1 ₂ , in which the channel setting section 8 is formed by something like a pin board, and the modulation section is formed by an arithmetic processing LSI such as a microcomputer. A wave generating circuit 9, a reference signal generating circuit 10 with an oscillation frequency of about 300 KHz that supplies a reference clock signal to the modulated wave generating circuit 9, a carrier wave generating circuit 11 having an oscillating frequency of about 300 MHz, and this carrier wave generating circuit 11. The modulating circuit 12 is connected in series and is controlled by the output of the modulated wave generating circuit 9. Therefore, the modulated wave generation circuit 9
are connected to the respective terminals in the 4th row and 6th column of the channel setting section 8, and each of the 4th row of the channel setting section 8 selects each modulation frequency, and each of the 6th column selects each timing in time series. The output of the modulated wave generation circuit 9 sequentially specifies the readout timing of each of the six columns, and the channel set row in the specified column (that is, the modulation frequency to be generated at that timing) is specified. The reference clock signal output from the reference signal generating circuit 10 is frequency-divided based on the read data signal to output a predetermined modulated frequency signal. The modulated frequency signal, which is obtained as the output of the modulated wave generation circuit 9 and which changes moment by moment at each time point in the time series, is input to the modulation circuit 12, and the 300MHz carrier wave generated by the carrier wave generation circuit 11 is It is modulated by a modulation frequency signal obtained by combining and arranging six modulation frequencies in time series, and is emitted into space from an antenna that also serves as the oscillation coil 13. Therefore, as shown in Figure 3, the transmitted radio wave is a signal modulated at one of the four modulation frequencies at each of the first to sixth time timings in the time series. be.

Figure 4 shows receiving unit 2 and display unit 3.
₁ , the receiving unit 2 includes a front end 14 composed of, for example, a super regeneration circuit including two transistors,
Gain up 15 set to about 80dB gain
, four band-pass type filter circuits 16 ₁ ... 16 ₄ whose center frequencies are set to f ₁ to f ₄ , and comparators 17 ₁ ... 17 that respectively discriminate the outputs of these filter circuits 16 ₁ ... 16 ₄ . The display unit ₃₁ is composed of a channel setting section ₅₁ formed of something like a pin board, and the outputs of the _four groups of comparators ₁₇₁ to 17 formed of an arithmetic processing LSI such as a microcomputer _. and a channel display discrimination circuit 18 which inputs the output of the channel setting section 5 _1. The channel discrimination circuit 18 stores the input signal in an internal memory, compares this with the self-set channel, and if they match, strobes. A signal is output, and a channel match signal is output to the notification sound generation circuit 20 via the monostable oscillator 19. however,
The self-configuring channel has a part in internal circuitry, which changes the output state (output to the binary decimal decoder 21). In Fig. 4, the information processing functions of _S5 and _S6 are internally included. 21 is a binary decimal evolution decoder, 22 is an R/S latch, 23 is an output state change circuit, and _{24 is} a driver circuit. 25 ₂ ...25N is driven to display the channel, and the output state change circuit 23
is set by the display mode changeover switch ₇₁ , for example,
Minute timer a, 1 minute timer b, R/S latch C
It can be changed as follows. Note that the display ₃₂ is similarly constructed and connected to the receiving unit 2 in parallel.

Now, the modulated carrier signal received by the receiving antenna 26 is amplified and demodulated by the front end 14,
Each filter circuit 16 ₁ via gain up 15
...16 Input in parallel to ₄ . Filter circuit 16 ₁
... ₁₆₄ corresponds to each of the four modulation frequencies _f1 ... _f4 , outputs are produced from the filter circuits ₁₆₁ ... ₁₆₄ that match the frequency of the demodulated signal received at that time, and the comparators ₁₇₁ ... 17 ₄ , it is determined whether or not an output has occurred in each corresponding filter circuit 16 ₁ ... 16 _4. Therefore, depending on the frequency of the demodulated signal received at that time, one of the comparators 17
Output is generated at ₁ ...17 ₄ and the channel discrimination circuit 18
will be entered into. Channel discrimination circuit 1
8 inputs each output of the comparators 17 ₁ ... 17 ₄ as described above, and a channel setting section 5 ₁
Column signals are sequentially specified for the pin boat matrix, and the output from the row where the channel setting has been performed in the specified column is read. First, the first demodulated signal in the time series is used to If an output is generated in the comparators 17 ₁ ... 17 ₄ , the number of the comparator 17 ₁ ... 17 ₄ that generated this output and the read command signal in the first column as the first in the time series are sent to the channel setting section 5 ₁ . When given, the channel discriminating circuit 18 compares and discriminates the number of the channel-set row in the first column read into the channel discriminating circuit 18, and if they match, the comparator 17 ₁ uses the next second demodulated signal. The comparator ₁₇ waits for the operation _of .
When the number ₁ ... ₁₇₄ matches the number of the channel-set row in the second column, the third reception waiting state is entered in the same manner. In this way, the numbers of the activated comparators 17 ₁ ... 17 ₄ at the first to sixth time timings are respectively assigned to the channels in the first to fourth columns of the channel setting section 5 ₁ and inside the channel discrimination circuit 18. When all of the set row numbers match, it is determined that the channel of the display unit ₃₁ has been called, and a channel matching signal is output, the notification sound generation circuit 20 is activated to emit a notification sound, and the display element 25 ₁ , 25 _{2 .} . . 25N are lit to display the channel.

FIG. 5 is a circuit diagram of one embodiment of the driver circuit in FIG. 4, where 27 is a timer, 28 is an oscillator,
29 and 30 are NAND gates, and 31 is an inverter. Now, when the input signal from the output state changing circuit 23 enters the point A as shown in FIG. 6a, the timer 27
is turned on for a certain period of time, and the output at point B becomes as shown in FIG. 6b. This output and the output of the oscillator 28
The signal is input to the NAND gate 29, and its output point C is as shown in FIG. 6c. Therefore, the output of the NAND gate 30 (point D) becomes as shown in FIG. 6d, and a voltage having the waveform shown in FIG. 6e is applied to the display element ₂₅₁ , so that the display element 251 can flicker for a certain period of time at the initial stage of lighting. Similarly, the display elements 25 _{2 .} . . 25N can be flickered in the initial stage of lighting. Therefore, when lighting a plurality of display elements in a channel, the calling order can be easily determined.

As described above, the present invention is composed of one receiving unit and a plurality of display units, the display unit is configured to be able to display a channel separately using a plurality of display elements, and the display unit is arranged in parallel with the receiving unit. By connecting multiple display elements, it is possible to eliminate the disadvantage of providing a reception function for each display unit, that is, the reduction in S/N ratio due to unnecessary radiated radio waves between the reception function units, and also to allow separate channels for multiple display elements. Since it is equipped with an output state changing means that can select and set the light emitting display state of the display element, it is possible to display information from multiple places simultaneously on the display unit, and therefore it is possible to display information from multiple locations at the same time. Even if duplicate information such as ordering information is sent, it is possible to simultaneously display the information corresponding to each table, and the display state of the display element can be selectively set by the output state changing means. The user can freely set the settings according to the installation location, purpose of use, etc., which greatly contributes to accurate understanding of information.

The driver circuit that drives the display element is provided with a timer that is turned on for a certain period of time by an input signal, and the output of the timer and the output of the oscillator cause the display element to flicker for a certain period of time from the start of lighting.
This has the effect that when a plurality of display channels are lit, it is possible to easily determine temporal relationships such as calling order.

[Brief explanation of drawings]

FIG. 1 is a front view of an embodiment of the reception display system of the present invention, and FIG. 2 is a circuit diagram of the same transmitting unit.
Fig. 3 is a waveform diagram of the transmission signal as above, Fig. 4 is a block circuit diagram of the receiving unit and display unit as above, Fig. 5 is a circuit diagram of the driver circuit as above, and Fig. 6 a to e are main parts as above. It is a signal waveform diagram. 1 ₁ , 1 ₂ ... transmitting unit, 2 ... receiving unit,
3 ₁ , 3 ₂ ... display unit, 4 ₁ , 4 ₂ ... display section, 2
4... Driver circuit, 25 ₁ , 25 ₂ ... 25N... Display element, 27... Timer, 28... Oscillator.

Claims (1)

[Claims] 1. In a reception display system that receives and displays radio waves emitted from a transmission unit that emits radio waves unique to each location from multiple locations, the system is composed of one reception unit and a plurality of display units, and the display unit is The display unit is provided with an output state changing means that allows a plurality of display elements to perform channel display separately and that can select and set the light emitting display state of the display elements, and the display unit is connected in parallel to the reception unit, The display unit is provided with a timer that is turned on for a certain period of time by an input signal in the driver circuit that drives the plurality of display elements that display channels, and the output of the timer and the output of the oscillator cause the display elements to flicker for a certain period of time from the start of lighting. A reception display system characterized by: