EP1282095B1 - Method of radio communication in an alarm system - Google Patents

Description

description

Method for radio transmission in a hazard detection system

The invention relates to a method for radio transmission in a hazard detection system.

Funk is a nearly ideal transmission medium for building technology. Devices with radio technology are quick to install and easy to adapt to changing requirements. However, a disadvantage is the relatively short range in buildings with carrier frequencies in the gigahertz range. If so-called repeaters are used to increase the range, the high energy consumption still requires mains-powered devices. This is especially true for radio equipment in the new SRD band between 868 and 870 MHz.

In systems with repeaters to increase the range of information across multiple stations in a short time must reach their destination. This short time is measured in terms of building security (fire alarm, intrusion protection) in just a few seconds and in building automation (lighting systems) in less than a second.

However, powerful computers are needed to find the right path through a widely ramified network. It probes probabilities, preselects paths, creates statistics, etc. All of this requires space, computing power, and last but not least lots of electrical energy. Even a year-long supply of batteries is currently not possible.

Out EP 0 833 288 a method for radio transmission in a danger detection system is known in which measurement data of a detection sensor to the central unit via other alarm sensors are transmitted as a stopover. This is a fixed hierarchical connection structure of the detection sensors with each other intended. The fixed structure does not allow the free communication of the detection sensors with each other.

The EP 0811959 B1 describes a radio-controlled security alarm system, in particular fire alarm, intruder alarm, emergency call, paging or alarm system, with at least one detector or a signal detector unit, at least one sub-center and a control center. A detector or a signal signaling unit consists of a transmitter, a receiver, a microprocessor system and a sensor. A sub-center consists of a transmitter, a receiver and a microprocessor system. The control center consists of a transmitter, a receiver and a microcomputer system.

The USA 4782846 describes a wireless LAN network for digital data transmission to and from building units, such as homes in the neighborhood, in a region.

It is therefore an object of the invention to provide a method for radio transmission in a hazard detection system, which is suitable for the repeater operation, ensures short reaction times and allows individual communication among the participants of the system.

The object is achieved by a method for radio transmission of the aforementioned type with the features of claim 1.

It is envisaged that telegrams are transmitted by participants willing to send to the participants via so-called. Mediating participants and that in a memory device of the participants a list is stored in which the addresses of the mediating participants are stored, if provided for the reception Participants can not be reached directly. These have a configuration mode for configuring the subscribers, in which the subscribers look for other subscribers in the configuration mode Search and find other participants in their list. Information about the subscribers who have not found each other directly in the configuration mode is transmitted to the subscribers via the mediating participants, after which these subscribers supplement their lists. The particularly simple configuration method provides that the participants themselves are brought into a configuration mode during the first startup, in which the participants search for the other participants and include them in their lists when they are found. This minimizes the configuration effort.

For the joint achievement of different participants is provided according to claim 2 in an advantageous manner that this list also includes a group affiliation.

In methods in which the frequency is changed, it is provided according to claim 4 in an advantageous manner that is also noted in the list over which frequency channel of the intended for receiving participants can be achieved.

In accordance with claim 5, a method with frequency change can be made simpler by the fact that a change of the frequency channels takes place according to an education law known to all participants.

According to claim 6 is provided in a disturbance of the transmission between two participants, that the intended for the reception of participants via other - then mediating - participants is achieved.

According to claim 7 is provided in an advantageous manner that an excellent participant optimizes the lists of other participants and sends these optimized lists to the other participants.

According to claim 8, the receiving means of the subscribers are cyclically turned on at predetermined times, and senders requesting send preambles containing the address of the subscriber who is to receive the preamble. If a receiving device now receives one of the preambles which is addressed to this receiving device, then the receiving device remains switched on until the complete preamble has been received, and in the event that no preamble has been received, the receiving device is switched off again. In the latter case, the cycles are chosen so that the time interval in which the receiving device is turned off, compared to the time interval in which the receiving device is turned on, by more than a factor of 5 is greater. This method ensures that the receiver remains operational for a few years via a battery, such as a low-cost AA cell.

In the advantageous embodiment of the method according to claim 9, the receiving device changes in the on state, the frequency of the reception frequency to meet the currently valid in the US FCC rule for frequency hopping.

According to claim 10 is provided for complex transmissions, that in the preamble, only the start time of the actual data telegram is transmitted, and the receiving device turns on at this start time, and the transmitting party sends out the corresponding data telegram at this start time.

The radio communication can be further reduced according to claim 11, in the case of a desired transmission to several intended for the reception of the participants willing to send the preamble only once, and the associated receiving devices remain turned on until the preamble was received.

In the following the invention will be explained in more detail with reference to the figures in the drawing.

• Figur 1 eine schematische Ansicht eines Gefahrenmeldesystems mit drei Teilnehmern,
• Figur 2a und 2b Beispiele für Listen, wie sie in der Speichereinrichtung abgespeichert sind,
• Figur 3a und 3b die Listen zweier Teilnehmer im Konfigurationsmodus, die Figuren 4a, 4b und 4c die Listen von drei Teilnehmern im Konfigurationsmodus,
• Figur 5 die Liste eines Teilnehmers, in der zusätzlich die Gruppenzugehörigkeit der verschiedenen Teilnehmer eingetragen ist und
• Figur 6 die Liste eines Teilnehmers mit Frequenzkanälen, die für die Übertragung vorgesehen sind.

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• FIG. 1 a schematic view of a hazard detection system with three participants,
• FIGS. 2a and 2b Examples of lists, as stored in the memory device,
• Figure 3a and 3b the lists of two participants in configuration mode, the Figures 4a, 4b and 4c the lists of three participants in configuration mode,
• FIG. 5 the list of a participant in which additionally the group affiliation of the different participants is registered and
• FIG. 6 the list of a subscriber with frequency channels intended for transmission.

In FIG. 1 It is shown how a first subscriber 1 is equipped with a first transmitter 2 and a first receiver 3, wherein the first subscriber 1 with a second subscriber 4 (which also includes a second transmitter 5 and a second receiver 6) and with a third Subscriber 7 (with a third transmitter 8 and a third receiver 9) forms a hazard detection system. The individual subscribers 1, 4, 7 can have, for example, additional sensors which, for example, detect a fire hazard or detect a burglary attempt as motion detectors. In addition, subscribers 1, 4, 7 can also assume central functions, for example initiate an alarm or display a building view with the corresponding alarm locations. It is also conceivable that the individual participants have 1,4,7 actuators to close doors, turn on lights or set blinds in motion.

The necessary RF receivers in the range of 1 GHz today typically consume 10 to 30 mA from 3 V. The life of a battery should be about 4 years. According to the invention, the receiver checks regularly (for example every 300 ms) whether a subscriber willing to send is active. The settling time of the receiver must be so small that the resulting average current does not load the batteries too much. Settling times of less than 1 ms are currently technically possible.

A subscriber willing to send now sends a preamble that allows the recipient to recognize the request. In the present example, this preamble must be sent for 300 ms to ensure that the subscriber intended for reception then also has its receiver switched on. This preamble does not necessarily have to be empty; it may, for example, contain the entire data telegram.

Additional information in the preamble may indicate, for example, the start time of the actual telegram. The receiver is then turned off again until the beginning of the payload, and thus can save power.

To comply with the US FCC Frequency Change Policy, the frequency of the receiving channels will be changed during the time the receiver is turned on.

If a station willing to send has to make contact with several other subscribers, the preamble is sent out only once and the associated subscribers intended for receiving do not switch off immediately but wait for the telegrams to be exchanged.

For the organization of the network, it is provided that in a radio cell with, for example, n-subscribers, each subscriber keeps a list that provides information about which next subscriber (mediator) that can reach any other subscriber of the radio cell. Such a list is exemplary in FIG. 2a shown. In this list for the participant 7 is in the first line to be reached Registered participants and in the second line of the designated first mediator. The in FIG. 2a shown participants 7 reaches the participants 5,6 and 8 directly, while the participants 1 to 4 on the participants 5, the participants 9 and 10 can be reached via the participant 6. In this case, the statement that the subscriber 2 is to be reached via the subscriber 5 does not mean that the subscriber 5 has direct contact with the subscriber 2. Another intermediary may well be provided, as shown in the example list of subscriber 5 in FIG FIG. 2b is shown.

According to the invention, it is provided that the first-time extraction of the list is done without an additional tool. For this purpose, the following steps are performed: first, the first participant of the radio cell is brought into a configuration mode. The subscriber searches for existing subscribers in configuration mode. Since the first party does not find another such party, that party itself defines a cell number and waits for other participants to log in to it.

The second station of the radio cell is put in the configuration mode. He finds the participant 1 and is integrated into the system as number2. Both now each have a place in their list, as in FIG. 3a for the participant 1 and FIG. 3b for the participant 2 is shown.

Subsequently, the third party is brought into the configuration mode. If, for example, he finds only subscriber 2, but not subscriber 1, he can have his list transmitted to him. Thus, the third participant knows that he can reach the participant 1 via the participant 2. The participant 2 now transmits to the participant 1 that the participant 3 can reach him (the participant 2). The corresponding stored lists then correspond to the participant 1 of the FIG. 4a , for the participant 2 of the FIG. 4b and for the participant 3 of the Figure 4c ,

If the connection between two subscribers n and m is lost, n tries to re-establish the connection via another subscriber. For this purpose, this participant turns to the participants, which he can reach directly and checks whether they have contact to n. If so, the participant will correct his list accordingly. For the participant m the corresponding applies.

In FIG. 5 is shown that each participant of a radio cell can be assigned to one or more functional groups. These function groups are mapped in further lines of the lists as described in FIG. 5 represented by the letters A, B and C. In this case, each participant, as shown, at the same time belong to several groups, as it is in the example of the participants 4.7, which also belongs to the groups A and B. With the help of such groups, for example, lamp collectives can be switched together.

If a broadcast message is now sent to such a group, and a subscriber receives such a message and belongs to the specified collective, he executes the command, even if he is not addressed directly to him. In this case, a receipt is omitted. In this way, the reaction time of a group can be drastically shortened. A following directly addressed command with the same content has no effect, but is acknowledged. To optimize the lists, it is envisaged that an excellent subscriber of the cell has the right to optimize the list of other subscribers. For this purpose, this excellent participant collects the lists of all participants and optimizes them on the basis of, for example, further attributes of the connections such as field strength or error frequency. After the excellent subscriber has optimized the cell's connection network, He sends the lists back to the individual participants.

For systems with frequency changes, it is additionally provided that it is shown in the lists via which frequency channel the respective subscriber can be reached in the next cycle. One such example is in FIG. 6 shown. In the FIG. 6 If this sends a telegram to the subscriber 8, he turns to the subscriber 7 and uses it for the frequency channel No. 12. Since the channel numbers must be changed regularly, this has in the context of normal telegrams to happen. The future channel number of the old telegram will be indicated.

If the channel change is carried out according to an education law known to all subscribers, then even in the case in which a telegram is lost, the corresponding partner can einphasen by the fact that he tries to restore the follow-up channels according to the Education Act contact.

This represents a power-saving, spontaneously responding radio system, which enables battery-powered repeaters. However, the microcontrollers used need only a small main memory. Despite the possibility of autorouting, one word per station is sufficient for the radio cell.

Claims (11)

1. Method of radio transmission in an alarm system with a number of users (1, 4, 7), each having a transmitter (2, 5, 8) and a receiver (3, 6, 9),

   - with telegrams being transmitted from users (1, 4, 7) wishing to transmit via one or more mediating users (1, 4, 7) to a user intended for receiving (1, 4, 7),

   - with a list being stored in a memory device of the user (1, 4, 7) in which all users intended for receiving (1, 4, 7) are assigned a list entry, which, in the event of direct accessibility of the user intended for receipt (1, 4, 7) is the number of this user (1, 4, 7) and in the case of unavailability of direct accessibility is the number of the next user, a mediating user (1, 4, 7),

   - with, for configuring the users (1, 4, 7), these having a configuration mode in which the users (1, 4, 7) search for other users (1, 4, 7) in configuration mode and on finding other users (1, 4, 7) enter these into their list, and

   - with information about the users (1, 4, 7), which have not been found directly in configuration mode being transmitted via the mediating users (1, 4, 7) to these users (1, 4, 7), after which these users (1, 4, 7) supplement their lists.
2. Method of radio transmission according to claim 1, characterised in that
   a number of users (1, 4, 7) are combined into a group and the group membership is likewise flagged in the list.
3. Method of radio transmission according to claim 2, characterised in that
   certain telegrams are sent to a group and the content of these certain telegrams is followed by all users who belong to the addressed group.
4. Method of radio transmission according to one of claims 1 to 3, characterised in that the frequency channel via which the corresponding user (1, 4, 7) can be reached is flagged in the list.
5. Method of radio transmission according to claim 4, characterised in that
   a change of frequency channels is undertaken using a formation law known to all users (1, 4, 7).
6. Method of radio transmission according to one of claims 1 to 5, characterised in that

   - on loss of the connection between two users (1, 4, 7) the user (1, 4, 7) wishing to transmit interrogates all users to be reached directly without the aid of the mediating users (1, 4, 7) as to whether the user (1, 4, 7) intended for receiving can be reached from these users (1, 4, 7) to be reached, and

   - in the event of the user (1, 4, 7) intended for receiving being able to be reached via another user (1, 4, 7) able to be reached directly, the list in the user (1, 4, 7) wishing to transmit is corrected accordingly.
7. Method of radio transmission according to one of claims 1 to 6, characterised in that

   - the lists of all users (1, 4, 7) are transmitted to an identified user (1, 4, 7),

   - this identified user (1, 4, 7) optimises the lists of the other users (1, 4, 7) and

   - the identified user (1, 4, 7) transmits the optimised lists to the other users (1, 4, 7) which store these in their memory unit in place of the original list.
8. Method of radio transmission according to one of claims 1 to 7, characterised in that

   - the receiver (3, 6, 9) is switched on cyclically at predetermined points in time, and

   - the recipients (3, 6, 9), in the event of receipt of a preamble, remain switched on until the end of the complete preamble and in the event of no preamble being received are switched off again, so that in this case the time interval during which the recipient (3, 6, 9) is switched off is greater by more than a factor of 5 than the time interval during which the recipient (3, 6, 9) is switched on.
9. Method of radio transmission according to claim 8, characterised in that
   the communication users switch the frequency channel.
10. Method of radio transmission according to one of claims 8 or 9, characterised in that,

    - the start time of a data telegram is transferred in the preamble,

    - the recipient (3, 6, 9) is switched off after receiving the start time and is switched on again at this start time, and

    - that the user (1, 4, 7) wishing to transmit transmits the telegram at this start time via its transmitter (2, 5, 8) and this is received by the recipient (3, 6, 9).
11. Method of radio transmission according to one of claims 8, 9 or 10, characterised in that
    the user (1, 4, 7) wishing to transmit, in the event of a desired transmission to a number of users (1, 4, 7) intended as recipients, only sends out the preamble once with the associated receive addresses.

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