JPH0652459A - Fire alarming device - Google Patents

Abstract

PURPOSE:To enable polling transmission between a receiver and a terminal without requiring any address by utilizing a spectrum spread communication. CONSTITUTION:Each of repeaters 14-1 to 14-n is provided with a pseudo-random series generation part 20 which generate a different and characteristic pseudo- random series previously assigned to the corresponding repeater, a reception part 22 which receives and demodulates a signal from the receiver 10 by using the pseudo-random series generated by the pseudo-random generation part 20, and a transmission part 24 which sends the signal from the repeater to the receiver 10 by using the pseudo-random series generated by the pseudo-random series. Further, the receiver 10 is provided with a pseudo-random series switching generation part 30 which generates one of the same plural pseudo-random series as the characteristic pseudo-random series set in the repeater by switching, a transmission part 34 which sends the signal from the receiver to the repeater side by using the pseudo-random series generated by the switching, and a reception part 36 which receives and demodulates the signal from the repeater by using the pseudo-random series generated by the switching.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention transmits a fire signal or a fire-related signal between a receiver and a repeater or between a receiver or a repeater and a fire detector by using spread spectrum communication (SS). The present invention relates to a fire alarm device.

[0002]

2. Description of the Related Art In a conventional fire alarm device, a plurality of repeaters are connected to a transmission line drawn from a receiver, and a fire detector is connected to a transmission line drawn from each repeater. There is. An address is set in advance in the repeater, and the receiver specifies the repeater address in order, sends a command together with the address, and performs polling to send back information about the fire from the repeater with a matching match of the address. ing.

In this respect, the polling from the repeater is similarly performed between a plurality of fire detectors connected to the transmission line from the repeater, and information about the fire is collected by the repeater. .

[0004]

However, in such a conventional fire alarm device, an address must be set in advance in order to poll the repeater from the receiver, which increases the number of terminals. Therefore, there is a problem that the number of bits of the address becomes large, the processing cycle of the address transmission and the address discrimination becomes long, and it takes time.

Further, although the fire alarm device uses a dedicated transmission line, it is susceptible to noise and transmission deterioration because no measures such as equalization compensation for transmission deterioration are taken unlike telephone lines. , There is a possibility that an error will occur in the address data during transmission and incorrect addressing will be performed. Furthermore, it is conceivable to use a dedicated transmission line of the fire alarm device to send information related to the fire, such as the voice of the fire occurrence location, image data captured by an ITV camera, etc., to the receiver side for restoration output. However, since it affects the transmission of fire signals, it is necessary to send it so that the timings do not overlap, and there is a problem that high-speed and high-bandwidth data transmission cannot be expected because the transmission quality is not so high. .

The present invention has been made in view of the above-mentioned conventional problems, and provides a fire alarm device capable of polling transmission between a receiver and a terminal using spread spectrum communication without any address. The purpose is to provide. Another object of the present invention is to provide a fire alarm device that can use the transmission line of the fire alarm device as it is to send various information related to a fire without affecting the transmission of the fire signal. The purpose is to do.

[0007]

To achieve this object, the present invention is constructed as follows. First, the present invention is directed to a fire alarm device in which one or more repeaters are connected to a transmission line drawn from a receiver and a fire detector is connected to the transmission line drawn from the repeater.

According to the present invention for such a fire alarm device, first, pseudo-random sequences for generating different pseudo-random sequences PN _{1 to} PN _n, which are unique to each repeater and are previously assigned to each repeater. The generation unit, the reception unit that receives and demodulates the signal from the receiver using the pseudo-random sequence generated by this pseudo-random generation unit, and the signal from the repeater using the pseudo-random sequence generated by the pseudo-random generation unit. And a transmitter for transmitting to the receiver.

On the other hand, the receiver has a plurality of pseudo-random sequences PN that are the same as the unique pseudo-random sequences set in the repeater.
A pseudo random sequence switching generation unit that is generated by switching to any one of _{1 to} PN _n , and a signal from a receiver is transmitted to the repeater side using the pseudo random sequence generated by this pseudo random sequence switching unit. And a receiving unit that receives and demodulates the signal from the repeater using the pseudo random sequence generated by the pseudo random sequence switching unit.

Such a configuration can be similarly applied when the fire detector is directly connected to the transmission line from the receiver, or between the repeater and the fire detector. Further, the present invention provides a data transmission section for transmitting arbitrary information related to a fire to a repeater side, and a transmission for transmitting a signal from the data transmission section to a receiver side using a predetermined pseudo random sequence PN _0. On the other hand, on the other hand, on the receiver side, a receiver that receives and demodulates the data signal from the data transmitter using the same pseudo-random sequence as the pseudo-random sequence, and any information related to fire from the received data of the receiver And a data restoring unit for restoring the data.

[0011]

According to the fire alarm system of the present invention having such a configuration, when a specific repeater is called, a spectrum using a pseudo-random sequence previously assigned to the called repeater by the receiver is used. All that is necessary is to send a command signal by spread spectrum modulation, and no address is required.

On the repeater side, a signal from the receiver is received and demodulated using a pseudo-random sequence assigned in advance, and no reception output can be obtained unless the same pseudo-random signal is received. It is possible to receive and demodulate only the signal transmitted from the receiver using the self-assigned pseudo-random sequence without requiring discrimination. Further, the reception demodulation of the data bit by the pseudo-random signal is determined from the peak value by the autocorrelation calculation. Therefore, when the number of sequence elements is N, it is -1 / N when the reception sequences do not match, When it matches the received sequence, an N-fold received S / N ratio is obtained, and the reliability of data transmission is extremely high without being affected by transmission deterioration.

Furthermore, by transmitting the information related to the fire from the terminal side to the receiver side by spread spectrum communication using a predetermined pseudo-random sequence, the transmission line of the conventional fire alarm system can be used as it is. However, when viewed from the fire signal, the pseudo-random sequence signal can be seen only as weak noise, and the fire-related information can be reliably transmitted without affecting the fire signal.

[0014]

1 is a block diagram showing an embodiment of the present invention. In FIG. 1, repeaters 14-1, 14-2, ... 14 are provided on the transmission line 12 drawn from the receiver 10.
-N is connected. In addition, each of the repeaters 14-1 to 14-14
A fire detector 18 is attached to the transmission line 16 drawn from -n.
Are connected. The repeaters 14-1 to 14-n are, as represented by the repeater 14-1, represented by the PN generator 20, SS.
The receiver 22, the SS transmitter 24, the controller 26, and the transmission controller 28 are provided.

In the first embodiment, the repeater 14-1
To 14-n are previously assigned pseudo random sequences PN used for spread spectrum communication (SS), and the pseudo random sequences assigned to the relays 14-1 to 14-n are PN ₁ to PN _n. And a different series. As the pseudo-random sequences PN _{1 to} PN _n , the number of sequence elements N
It is possible to use an M-series signal or a gold-series signal having a predetermined bit length determined by, for example, 511 bits.

On the other hand, the receiver 10 has a PN switching generator 3
0, a control unit 32, an SS transmission unit 34, an SS reception unit 36, an operation unit 38, and a display unit 40 are provided. Since the PN switching generator 30 sequentially calls the repeaters 14-1 to 14-n,
The pseudo random sequences PN _{1 to} PN _n are switched and generated at fixed intervals, and the SS transmitter 34 and the SS receiver 3
Set to 6. The SS transmission unit 34 transmits the command from the control unit 32 to the pseudo-random sequence PN corresponding to the specific repeater generated by the PN switching generation unit 30 at the current switching time.
i is used for spread spectrum modulation and the transmission line 12
Send to. In addition, the SS reception unit 36 demodulates the reception signal from the repeater side using the same pseudo-random sequence PNi set in the SS transmission unit 34, and outputs the demodulated data to the control unit 32.
Output to.

FIG. 2 is a block diagram showing an embodiment in which the SS transmitter 24 provided on the repeater side and the SS receiver 36 provided on the receiver 10 side of FIG. 1 are taken out. First, the SS transmitter 24 includes a mixer 42 and a balanced modulator 44. On the other hand, the SS receiver 36 includes a mixer 46 and a parallel modulator
8, IF band pass filter 50 and PSK demodulator 52
Equipped with.

The PN sequence generator 20 of the SS transmission section 24
1 corresponds to the PN sequence generator 20 on the repeater side in FIG. 1, and the PN sequence generator 30a in the SS receiver 36 corresponds to the PN switch generator 30 provided in the receiver 10 in FIG. The spread spectrum communication system modulates the information signal of the casing with a pseudo random sequence signal having a high clock frequency,
Since the current information is frequency-spread and transmitted over a wide band, highly reliable communication can be realized even in an environment with a poor S / N ratio. In addition, the spread spectrum communication method is resistant to interference from other transmission sources and has a low required transmission power density. Therefore, unless the pseudo random sequence signal is known, the confidentiality of the current information cannot be restored by a third party. Have.

To realize such spread spectrum communication
In the embodiment shown in FIG. 2, the SS transmitter 24 transmits the data first.
Original signal a PSK-modulated according to data bits 0 and 1
For (t), the PN sequence generator 20a has a predetermined cycle.
The PN sequence signal p (t) as a carrier in the mixer 42.
To produce the transmitted signal s (t).
Be done. This transmission signal s (t) is transmitted by the balanced modulator 44.
Carrier signal cosω_Ct Is transmitted by modulating
It

On the other hand, on the SS receiver 36 side, the PN sequence generator 30a generates the same PN sequence signal as on the transmission side, and the balanced modulator 48 generates a carrier wave co having an intermediate frequency component IF.
s (ω _C + ω _IF ) t is modulated with a PN sequence signal, and a signal q having a pseudo inverse function with respect to the PN sequence signal p (t) on the transmission side.
(T) is generated. When the signal q (t) of the inverse function and the received signal are multiplied by the mixer 46 and the period of the received signal and the period of the signal q (t) of the inverse function are completely matched, the intermediate frequency signal dependent on the autocorrelation peak is generated. The obtained original signal a is obtained by the PSK demodulator 52 via the IF bandpass filter 50.
(T) can be demodulated.

FIG. 3 shows the SS transmitter 24 and S used in the present invention.
FIG. 11 is a block diagram showing another embodiment of the S reception unit 36,
This embodiment is characterized in that the pseudo random sequence signal is directly transmitted to the transmission line. In FIG. 3, first, on the SS transmission unit 24 side, the PN sequence generator 20a,
It is composed of a mixer 42 and a power amplifier 54. on the other hand,
The SS receiving unit 36 side includes an A / D converter 56, a shift register 58, a correlation calculator 60, a PN sequence generator 30a, and a comparator 62.

When the data bit of the transmission data a (t) is 1, the SS transmission section 24 amplifies the pseudo random sequence p (t) from the mixer 42 as it is by the power amplifier 54 and sends it to the transmission line 12. On the other hand, for data bit 0, the output of the mixer 42 becomes 0, and the pseudo random sequence p (t) is not substantially output. In the SS receiver 36, the received signal from the transmission line 12 is sampled by the A / D converter 56 and input to the shift register 58 as digital data. The shift register 58 has a number of stages corresponding to the number of elements of the PN series signal, for example, 511 stages, and A
The data sampled by the / D converter 56 is sequentially shifted and input.

The output of each shift stage of the shift register 58 is input in parallel to the correlation calculator 60, and the PN sequence generator 30a.
It is multiplied by each element of the PN series signal output in parallel, and the sum is obtained. That is, the correlation calculator 60 calculates the autocorrelation between the received sequence and the PN sequence serving as the reference sequence. When the received sequence input to the shift register 58 and the reference sequence fixedly generated by the PN sequence generator 30a match, the correlation calculator 60 outputs the autocorrelation peak value to the comparator 62, and the comparator 62 outputs the self-correlation peak value. The correlation peak value is determined and data bit 1 is output. When the autocorrelation peak value cannot be obtained from the correlation calculator 60 at the next sequence reception timing, the comparator 62 outputs the data bit 0.

FIG. 4 is a flow chart showing the processing operation in the receiver 10 of FIG. In FIG. 4, the receiver 10 first initializes a designated counter A indicating the PN sequence generated by the PN switch generation unit 30 in step S1 to set A = 1.
And Next, proceeding to step S2, the process proceeds to step S3 while switching to the generation of the A-th PN sequence designated by the counter A, and issues, for example, a relay polling command.

The command generated in step S3 is SS
The PN sequence that is given to the transmission unit 34 and is currently generated in the PN switching generation unit 30 in step S2, for example, the relay 14
The data bit indicating the command is spread spectrum modulated using PN ₁ corresponding to −1 and sent to the transmission line 12. At the same time, the same pseudo random sequence PN ₁ is set in the SS receiver 36, and the SS provided in the repeater 14-1
The response data using the pseudo-random sequence PN1 from the transmission unit 24 is ready to be received.

Then, in step S4, it is determined whether or not there is a response from the repeater side, and the generated pseudo random sequence PN
_When the response from the repeater 14-1 corresponding to ₁ is obtained,
Proceeding to step S5, the processing of predetermined reception data is executed. Subsequently, in step S6, it is determined whether or not the counter A has reached the number n of repeaters. If not, the counter A is incremented by 1 in step S7, and then the process proceeds to step S2, where the pseudo random number of the next repeater is obtained. The same polling process is performed by switching to the series PN ₂ .

As described above, in the fire alarm system of the present invention, the pseudo random sequences PN _{1 to} PN n unique to the repeaters 14-1 to 14- _n are assigned to the spread spectrum communication with the receiver 10. By doing so, it is possible to directly send and receive commands and data without requiring an address. Although the spread spectrum communication is performed between the receiver 10 and the repeaters 14-1 to 14-n in the embodiment of FIG. 1, it is similarly provided in each of the repeaters 14-1 to 14-n. A fire detection signal may be transmitted by polling without using an address by spread spectrum communication with the existing fire detector 18. The same applies to the fire alarm device in which the fire detector 18 is directly connected to the transmission line 12 from the receiver 10.

FIG. 5 is a block diagram showing a second embodiment of the present invention. In this embodiment, a spread spectrum communication is used for a conventional fire alarm device which performs polling using an address. It is characterized in that information related to fire is sent from the terminal side to the receiver side for restoration. In FIG. 5, the transmission line 12 drawn out from the receiver 10 is provided with repeaters 14-1 to 14-n, and the transmission lines 16 are further provided from the repeaters 14-1 to 14-n.
A fire detector is connected via. As in the conventional case, the receiver 10 calls the repeater by using the address data, and the repeater side returns the response data when the calling address from the receiver matches its own assigned address.

In addition to this, in the embodiment of FIG. 5, for example, the data transmission device 66 and the SS are provided near the repeater 14-1.
The transmitter 64 is provided, while the SS receiver 6 is provided on the receiver 10 side.
8 and a data restoration device 70. The data transmission device 66 on the terminal side is used for voice information or IT in the surveillance area.
The image data of the monitoring area captured by the V camera or the like is output to the SS transmitter 64.

The same pseudo random sequence PN ₀ is preset in the SS transmitter 64 and the SS receiver 68.
The transmitter 64 sends the data from the data sending device 66 to the transmission line 12 by spread spectrum modulation using the pseudo random sequence PN ₀ . SS receiver 68 is transmission line 1
The received signal from No. 2 is demodulated using the pseudo-random sequence PN ₀ , the demodulated data is output to the data restoration device 70, and the voice information and the image data obtained on the terminal side are restored. The information related to the fire may be sent by the data sending device 66 at all times, but may be sent when the fire is detected in the repeater 14-1. Similarly, the data restoration device 7
The restoration at 0 may be always performed, and the receiver 10
It may be performed when the fire signal is received at.

FIG. 6 shows a modification of the second embodiment of FIG. 5. In this embodiment, the repeaters 14-1 to 14-1 on the terminal side are shown.
14-n corresponding to a plurality of data transmission devices 66-1 to 6-6
6-n and SS transmitters 64-1 to 64-n are provided. Different unique pseudo-random sequences PN _{01 to} PN _0n are set in the PN sequence generators 20 of the SS transmitters 64-1 to 64-n on the terminal side.

On the other hand, an SS receiver 68 and a data restoration device 70 are provided on the receiver 10 side, and a matrix circuit 72 and a PN generator 74 are further provided. The matrix circuit 72 receives the information received by the receiver 10 and receives and restores the transmission data from the data transmission device that is predetermined according to the reception location.
Alternatively, the PN generator 74 is instructed to generate a pseudo random sequence in the SS transmitter corresponding to a plurality of predetermined data transmission devices. The PN generator 74 sets one or a plurality of pseudo-random sequences to the SS receiver 68 based on the instruction from the matrix circuit 72. For example, pseudo-random sequence PN ₀₁
And PN ₀₂ are set.

Therefore, the SS receiver 68 uses the pseudo random sequence PN ₀₁ to transmit the data transmitting device 66-1.
Data and the data sent from the data sending device 66-n using the pseudo random sequence PN ₀₂ , and can be demodulated by the data restoring device 70. Of course, reception demodulation in the SS receiver 68 using a plurality of pseudo-random sequences is sequentially performed in the state where a plurality of data transmissions are being performed in parallel from the terminal side. Further, if the SS receiver 68 is provided with a plurality of SS receivers, reception demodulation from a plurality of data transmission devices can be performed in parallel.

In the above embodiment, the spread spectrum communication system as the direct spread system is taken as an example, but it goes without saying that the frequency hopping system (FH system) may be used.

[0035]

As described above, according to the present invention, an address is used by assigning a different pseudo random sequence to each terminal and performing polling from the receiver using the pseudo random sequence of the other party. It is possible to perform terminal polling without having to do anything, and it is possible to easily perform transmission by exchanging only commands and data.

Further, since the spread spectrum communication uses the pseudo random sequence, it is possible to perform highly reliable communication even if the transmission line is large. Furthermore, by transmitting the information related to the fire from the terminal side to the receiver side by spread spectrum communication to the existing fire alarm device using the address and restoring it, voice information and images can be displayed without affecting the existing fire signal. Information related to the fire, such as information, can be efficiently sent to the receiver side for restoration, and the state of the scene at the time of the fire can be properly grasped, and at the time of inspection of the fire alarm device, the terminal side and the receiver side It can also be effectively used for communication.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment showing a first embodiment of the present invention.

FIG. 2 is a block diagram showing an embodiment of an SS transmitter and an SS receiver.

FIG. 3 is a block diagram showing another embodiment of the SS transmitter and the SS receiver.

FIG. 4 is a flowchart showing a processing operation of the receiver of FIG.

FIG. 5 is a block diagram of an embodiment showing a second embodiment of the present invention.

6 is a block diagram of an embodiment showing a modification of the second embodiment of FIG.

[Explanation of symbols]

 10: Receiver 12, 16: Transmission line 14-1 to 14-n: Repeater 18: Fire detector 20: PN generator 22, 36: SS receiver 24, 34: SS transmitter 26: Repeater control Part 28: Transmission control part 30: PN switching generation part 32: Receiver control part 38: Operation part 40: Display part 42, 46: Mixer 44, 48: Balance modulator 50: IF band pass filter 52: PSK demodulator 54: power amplifier 56: A / D converter 58: shift register 60: correlation calculator 62: comparator 64: SS transmitter 66: data transmission device 68: SS receiver 70: data restoration device 72: matrix circuit 74: PN Generator

Claims (3)

[Claims] 1. A fire alarm device in which one or a plurality of repeaters are connected to a transmission line drawn from a receiver, and a fire detector is connected to the transmission line drawn from the repeater. A pseudo-random sequence generator that generates unique pseudo-random sequences that are different from each other and is assigned to each repeater, and a signal from the receiver is received using the pseudo-random sequence generated by the pseudo-random generator. A receiver for demodulating and a transmitter for transmitting a signal from the repeater to the receiver using the pseudo-random sequence generated by the pseudo-random generator are provided, and the receiver is unique to the repeater. The pseudo-random sequence generated by switching to any one of a plurality of pseudo-random sequences same as the pseudo-random sequence of A transmitter for transmitting a signal from the receiver to the repeater side, and a receiver for receiving and demodulating the signal from the repeater using the pseudo-random sequence generated by the pseudo-random sequence switching unit. Fire alarm device. 2. A fire alarm device in which a fire detector is connected to a transmission line drawn from a receiver or a repeater, wherein each of the fire detectors has a unique peculiarity assigned in advance for each repeater. A pseudo-random sequence generator that generates a pseudo-random sequence, a receiver that receives and demodulates a signal from a receiver or a repeater using the pseudo-random sequence generated by the pseudo-random generator, and the pseudo-random generator And a transmitter for transmitting the signal from the detector to the receiver or the repeater by using the pseudo-random sequence, and the receiver or the repeater is the same as the unique pseudo-random sequence set in the fire detector. A pseudo-random sequence switching generator that is generated by switching to any one of a plurality of pseudo-random sequences, and a receiver using the pseudo-random sequence generated by the pseudo-random sequence switching unit. A transmitter is provided for transmitting a signal from the relay to the sensor side, and a receiver is provided for receiving and demodulating the signal from the sensor side by using the pseudo random sequence generated by the pseudo random sequence switching unit. Fire alarm device. 3. A fire alarm device in which one or more repeaters are connected to a transmission line drawn from a receiver, and a fire detector is connected to the transmission line drawn from the repeater. The side is provided with a data transmission section for transmitting arbitrary information related to fire, and a transmission section for transmitting a signal from the data transmission section to the receiver side by using a predetermined pseudo-random sequence. A receiving unit that receives and demodulates the data signal from the data transmitting unit using the same pseudo-random sequence as the pseudo-random sequence, and a data restoring unit that restores arbitrary information related to fire from the received data of the receiving unit. A fire alarm device characterized by being provided.