• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The present invention relates to a public address system comprising a first (1) and a second (1) amplifier module, each comprising an amplifier means (2,2) and arranged to receive the same given signal to be applied to said amplifier means amplified signal. The first and second amplifier modules are interconnected via a first (LS1) and second (LS2) circuit. At least the first or second circuit includes at least one loudspeaker (11,11). The first circuit is arranged to supply the amplified signal from the first amplifier module to the second amplifier module and the second circuit is arranged to supply the amplified signal from said second amplifier module to said first amplifier module. The first and second amplifier modules each further include measuring means for comparing pairs of signals selected from the received given signals, the amplified signal output from the amplifier means contained in the amplifier module and the amplified signal from the other amplifier module and sent via the first or said second circuit, and to provide an indication of the operational status of the public address system based on those comparisons.
    公开号:BE1022225B1
    申请号:E2014/5099
    申请日:2014-12-01
    公开日:2016-03-02
    发明作者:
    申请人:Televic Rail；
    IPC主号:
    专利说明:

    Broadcasting system
    Field of the Invention The present invention relates generally to the domain of public address systems as used in public transportation.
    Background of the Invention In many public announcement systems, the announcer does not know whether the announcement is being played in all zones. For some applications, it is strongly recommended that the announcer be given an indication if the announcement could not be played.
    One option is to regularly perform a manual intervention to check that all speaker circuits in the different rooms are still functioning correctly. It goes without saying that this solution requires a certain effort that strongly depends on the accuracy and the interval of the check. Because this effort is often kept to a minimum in practice, there is a risk of hidden defects and therefore an unavailability of the system to broadcast messages in a certain zone.
    Another solution is an automated measurement of the system. Speech, however, is a complex waveform that is difficult to analyze if the correctness of the signal is to be checked. Reflections of the direct sound wave against the walls of a room make it even more difficult to use the signal for a control of the broadcast. A possible solution is to use a simple test signal, but it can be annoying to send a test signal while people are in the rooms. That is why such tests are only performed when nobody is present in the room. This planned test process again leads to periods in which hidden defects may occur in the system.
    As already mentioned, acoustic audio is difficult to measure due to sound reflections. Another disturbing factor is the noise present in a room. Examples are noise from air conditioning, talking people, etc. Performing an acoustic measurement is therefore not an option with some current solutions and only a check of the electrical signal is performed. This is applied in modern techniques such as "end of line" detection, impedance measurement and counter-electromotive force of the speakers. The speakers or their acoustic properties are only partially tested or not tested at all, depending on the measurement technology used. This means that the system can still show hidden defects in the speakers. The measurement does not even use the speech signal to be broadcast. Accordingly, the measurement does not provide relevant information as to whether or not the announcement is correctly announced. The measurement only shows whether the speaker circuits are capable of bringing signals to the speakers.
    Modern techniques such as speaker circuit impedance measurements or counter-electromotive force require complex measurement circuits and do not allow verification of the broadcast signal. Counter-electromotive force is a technique in which a signal pulse is sent to the speaker circuit and the speaker returns a signal pulse with which the presence of speakers in the circuit can be checked.
    Acoustic measurements have been made in the past with microphones. The analysis techniques are based on the time shift of signals from different speakers before those signals reach the microphone. However, these solutions imply an intrusive measurement (no verification of the broadcast signal) and therefore cannot be used for continuous testing.
    Application EP2381703 relates to a method and apparatus for controlling a loudspeaker circuit in a broadcast system. A main module is arranged at one point of a loudspeaker circuit and a control module is arranged at another remote point of the loudspeaker circuit. The two modules can communicate with each other. To send the digital communication signal, the impedance between the speaker circuit and a grounding reference of a communication member sending a signal changes.
    In WO2005 / 069685, an audible intelligibility system combines a broadcast system with a plurality of spatially separated sensors to evaluate the audibility of the audio output of the speakers in the broadcast system. Processing can take place with some or all sensors, as well as in a common control element. The evaluations may be based on the use of a predetermined voice transmission index.
    Consequently, there is a need for a simple solution to test the speakers in a public address system so that one is certain about whether messages are indeed being reliably transmitted.
    Summary of the Invention It is an object of embodiments of the present invention to provide a public address system that can test its speaker circuits in a simple manner. It is a further object of the invention to provide a method for acoustically testing the broadcast system.
    The above object is achieved by the solution according to the present invention.
    In a first aspect, the invention relates to a broadcast system comprising a first and a second amplifier module, each comprising an amplifier means and adapted to receive a given signal to be applied to the amplifier means and to send an amplified signal, wherein said first and second amplifier modules are interconnected via a first and second circuit, wherein at least the first or the second circuit comprises at least one loudspeaker, said first circuit being arranged to supply the amplified signal from the first amplifier module to the second amplifier module and the second circuit being arranged to supply the amplified signal from the second amplifier module to the first amplifier module, said first and second amplifier modules further comprising analysis means for comparing pairs of signals selected from the received given signal, said amplified signal d at is performed by the amplifier means included in the amplifier module and the amplified signal from the other amplifier module and sent through the first or said second circuit, and to provide an indication of the operational status of the broadcast system based on the comparisons.
    The proposed solution indeed makes it possible to test the speaker circuits without major inconvenience. The same signal is applied to both amplifier modules. The two amplifier modules are connected to two circuits, at least one of which contains one or more speakers. In each module, an amplifier amplifies the applied signal and outputs this amplified signal. The first circuit receives the first amplified signal and the second the other amplified signal. The signals are transmitted to the opposite side of the circuit, where they are received by the other amplifier module. On the basis of the applied signal, the amplified signal and the amplified signal received through the circuit of the other amplifier module, some comparisons are made in an analysis unit to determine whether an announcement has been correctly broadcast by the broadcast system.
    In a preferred embodiment, a first switch is provided in each amplifier module, which switch is adapted to disconnect the amplifier from the loudspeaker circuit. The first switch in each amplifier module is implemented in an advantageous embodiment as a high impedance state of the amplifier means. The provision of this first switch is particularly advantageous because it offers various options for diagnostic purposes.
    Preferably, a second switch is provided in each amplifier module, which switch is arranged so that the amplified signal from that amplifier module can be put on the circuit of a defective amplifier in the other amplifier module (the first switch being opened to release the amplifier) to link). If one of the amplifiers is defective, this offers the advantage that the other amplifier can take over the other loudspeaker circuit. In this way, a robust broadcast system is obtained in the event that one element fails.
    In one embodiment, the broadcast system comprises communication means for exchanging measurement results between the amplifier modules.
    In a preferred embodiment, the analysis means are arranged to compare the received data signal with the amplified signal in each amplifier module, to compare the received data signal with the amplified signal from the other amplifier module and to compare the amplified signal with the amplified signal signal from the other amplifier module.
    Advantageously, the system is also adapted to perform flow measurements.
    In one embodiment, the broadcast system is adapted to compare ambient noise measurements made on the first and second circuit.
    In another embodiment, the broadcast system is equipped to generate a test signal for acoustic verification of the at least one loudspeaker and / or the amplifiers. The acoustic verification is preferably carried out in real time.
    In another aspect, the invention relates to a method for verifying the operation of amplifier means and speakers in a broadcast system, comprising a first and a second amplifier module, each comprising amplifier means, said first and second amplifier module being interconnected via a first and second circuit, wherein at least the first or the second circuit comprises at least one loudspeaker. The method comprises the steps of: - applying the same signal to the first and second amplifier module, - sending the signals that were amplified by the amplifier means of the amplifier modules via the first and second circuit to the respective other amplifier module, - comparing , in each pair of amplifier modules, of signals selected from the applied signal, said amplified signal output from the amplifier means included in the amplifier module and the amplified signal from the other amplifier module and sent via said first or said second circuit, obtaining, based on the comparisons, an indication of the operational status of the broadcasting system.
    To summarize the invention and the realized advantages over the prior art, certain objects and advantages of the invention have been described above. It goes without saying that all such objectives or advantages are not necessarily achieved according to one specific embodiment of the invention. Thus, for example, persons skilled in the art will recognize that the invention may be embodied or embodied in a manner that achieves or optimizes one advantage or group of benefits as described herein, without necessarily realizing other goals or benefits described or suggested herein. .
    The above and other aspects of the invention will become clear and further explained with reference to the embodiment (s) described below.
    Brief description of the drawings The invention will now be further described, by way of example, with reference to the accompanying drawings, in which like reference numerals refer to like elements in the various figures.
    FIG. 1 illustrates an embodiment of the system according to the invention.
    FIG. 2 illustrates an embodiment that allows for further defect analysis.
    FIG. 3 illustrates an example of a system arrangement for acoustic verification.
    Detailed Description of Illustrative Embodiments The present invention will be described with reference to specific embodiments and with reference to certain drawings, but the invention is not limited thereto, but is only limited by the claims.
    In addition, the terms first, second, etc. are used in the description and in the claims to distinguish between similar elements and not necessarily for describing a sequence, either in time, in space, in importance or in any other way. It is to be understood that the terms used are interchangeable under proper conditions and that the embodiments of the invention described herein are capable of operating in sequences other than those described or illustrated herein.
    It is to be noted that the term "comprising" as used in the claims should not be interpreted as being limited to the means specified thereafter; it does not exclude other elements or steps. It must therefore be interpreted as a specification of the presence of the listed features, units, steps or components referred to, but it does not exclude the presence or addition of one or more other features, units, steps or components or groups thereof. Therefore, the scope of the expression "a device comprising means A and B" should not be limited to devices consisting only of parts A and B. It means that with regard to the present invention, the only relevant parts of the device A and B to be.
    References in this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or feature described in connection with the embodiment is included in at least one embodiment of the present invention. Statements of the phrase "in one embodiment" or "in an embodiment" at different places in this specification do not necessarily all refer to the same embodiment, but it is possible. Furthermore, the specific features, structures or characteristics may be combined in any suitable manner in one or more embodiments, as will be apparent to those skilled in the art from this disclosure.
    In a similar manner, it should be noted that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped into a single embodiment, figure, or description thereof to streamline the disclosure and understanding of one or more of the facilitate various inventive aspects. However, this method of disclosure should not be interpreted as an expression of an intention that the claimed invention requires more features than expressly stated in each claim. As shown in the following claims, the inventive aspects lie in less than all the features of a single preceding disclosed embodiment. Therefore, the claims that follow the detailed description are hereby explicitly included in this detailed description, wherein each claim stands on its own as a separate embodiment of the present invention.
    In addition, since some embodiments described herein include some, but not other, features included in other embodiments, combinations of features of different embodiments are intended to fall within the scope of the invention and form different embodiments, such as will be understood by someone skilled in this field. For example, in the following claims, any of the claimed embodiments can be used in any combination.
    It should be noted that the use of particular terminology in describing certain aspects of the invention does not imply that the terminology herein is redefined to be limited to any specific features of the features or aspects of the invention with which that terminology is associated.
    In the description given here, numerous specific details are set forth. However, it is understood that embodiments of the invention can be worked out without these specific details. In other cases, well-known methods, structures and techniques were not shown in detail in order not to obstruct the understanding of this description.
    The present invention proposes a broadcasting system with which it is easy to test whether an announcement is still being sounded correctly.
    The proposed system comprises in one embodiment two or more separate speaker circuits and two or more separate amplifier modules that are used to test the speaker circuits for availability. Fig. 1 is an illustration of this embodiment. The first amplifier module (referred to in the figure as amplifier module 1) receives the output signal from the second speaker circuit (LS2) and the second amplifier module (amplifier module 2) receives the output signal from the first speaker circuit (LSI). Making a comparison makes it easy to check whether the announcement is being correctly announced.
    Measuring means are provided in each amplifier module. As a minimum, measuring means are required on the low-level input signal (VI & V4) and on the end signal from the speaker circuit in the other amplifier module (V3 & V6). The final signal (V3) from the speaker circuit is checked against the low level incoming signal (VI) to be amplified. This test gives an indication of whether the other amplifier (amplifier 2) is still working properly and if there are no open circuits or short circuits in the other speaker circuit (LS2). As illustrated in Fig. 2, the measuring means and the comparators form part of what can generally be called an analysis unit 19, in which the measurements are performed and the measurement results are processed.
    In a further embodiment, measuring means are provided on the loudspeaker circuit (V2 & V5). By adding a comparison between the low level incoming signal (VI) and the amplified signal (V2), it can be detected whether the own amplifier (amplifier 1) is still working properly and whether there is no short circuit on the own speaker circuit (LSI). The signal VI may also be a separate signal representative of the low-level audio signal to be amplified.
    The block diagram in Fig. 2 illustrates an embodiment of the analysis unit (19, 19 ') that allows further defect analysis of the broadcast system. In each amplifier module, measured values obtained from the different measuring means are compared with each other. VI is compared to V3 by a comparator 20 which indicates whether VI is equal to V3. V1 is compared with V2 (21) to indicate whether V1 is V2 and V2 is compared with V3 (22) to check whether V2 and V3 are equal. By multiplying by a scaling factor 23 in multiplier 24 a scaling can be applied to the measurement VI. This scaling factor is determined when the system is designed and is equal to the gain factor of the amplifier. The comparisons are therefore V1 = f (V2, scale factor), V1 = f (V3, scale factor) and V2 = V3.
    The comparison results are sent to a processing unit 25. The processing unit can communicate comparison results (or a summary thereof) to other amplifier module (s) via a communication link 26. The communication can be performed via separate lines, one for each result, or by using a more extensive communication method such as RS485 or ethernet.
    A decision can be made based on the measurement results obtained in an amplifier module and based on measurement results communicated by the other module (s). In the event of a defect detection, the signal OUT OK is deactivated to indicate to the broadcaster that there is a defect in the amplifier module. The following table shows various defect analysis cases that may occur. The possible defects are shown in the left column. The following columns show the results of the various comparisons made by the amplifier modules. A "1" indicates that the signals are equal and a "0" indicates that the signals are different from each other.
    Some rows have the same combination (see the "Combination" column for the different letters) with comparison results, but using the switches allows further analysis to specify the defect.
    In a preferred embodiment, a first switch (SW1, SW3) is provided in each amplifier module to disconnect the amplifier from the speaker circuit. This switch allows the amplifier modules to deduce, if a defect occurs, whether the cause of the defect is the amplifier or the speaker circuit. When a defect occurs in the amplifier (amplifier 1 defective), a switch SW1 is opened to separate the speaker circuit LSI from the amplifier (Amplifier 1). Measured signals change accordingly and consequently the comparison results will also change at that time, in line with the diagnosed failure mode. This leads to a further deduction of which component of the amplifier is defective. The following table shows various initial actions and responses due to different failure modes.
    A second switch (SW4) can be closed to connect speaker circuit LSI to amplifier 2. In this way, the performance of the system does not decrease for the receiver of the announcement when an amplifier fails. In the case of a defect in amplifier 2, the switch SW3 will be opened to determine that the amplifier 2 is defective and that the defect is not caused by LS2. Subsequently, the second switch (SW2) can be closed to connect loudspeaker circuit LS2 to amplifier 1. In this way, the performance of the broadcasting system remains guaranteed to the public. The table below shows a complete mitigation scheme for different types of defects.
    The measurements and analyzes described above can be performed without the need for an additional (intrusive) test signal. The measurements are based on comparisons of signal pairs. A scaling may be applicable between the compared signals. The scaling factor is usually defined by the gain factor.
    The switch SW1, as well as SW3, can be a state of the amplifier with high impedance.
    The failure mode drift of a speaker circuit cannot be measured as can also be seen in the defect analysis table. Via current conversion means (9, 9 ') and measuring means 12 and 15 (10, 10') the current intensity can be measured to check the impedance of the loudspeaker circuit. This ensures detection of the LS-drift failure mode.
    Advantageously, the proposed structure is also suitable for taking measurements of the ambient noise present in both loudspeaker circuits. A comparison can be made between the ambient noise at the LS1 circuit and the LS2 circuit. A more reliable measurement of the noise can be obtained with this method.
    An intelligible announcement is obtained if the announcement is broadcast on 70dBSPL while the ambient noise is quieter than 60dBSpL or 10dB above the ambient noise if the ambient noise is louder than 60dBSPL. Environmental noise louder than 60dBSPL often occurs in a train or in an industrial environment. To make an intelligible announcement, the level of environmental noise must be known. A sound measurement can be performed through the speakers. The loudspeaker line becomes floating by opening the first switches (SW1, SW3) and thus acoustic noise around the loudspeakers is converted into an electrical signal on the loudspeaker circuit.
    There are two loudspeaker circuits that arrive at each amplifier module, so the sound measurement can be performed with redundancy in each amplifier module. The margin of error of the measurement can be reduced by using the value of the two circuits. In amplifier module 1, a noise measurement is carried out with measuring means V2 and V3, while in amplifier module 2 measuring means V5 and V6 are used. Advantageously, the noise measurement can also be used to further diagnose the amplifier modules. This is also clear on the basis of the tables above. Therefore, the location of the measuring means V2 and V5 is important: they must be located between the first switch (SW1, SW3) and the loudspeaker circuit leaving the amplifier module and not between the amplifier 2 and the first switch.
    The proposed structure is also suitable for acoustic verification of the system. A simple test signal can be used for acoustic measurement to avoid complex analysis methods. The speakers are used to measure the broadcast acoustic signal. This is an intrusive test that can reduce the comfort of the listeners present during testing. However, if combined with the continuous testing method described earlier, the acoustic tests can be limited to periods when there are no people in the room (for example, before people gain access to the room). This leaves only a small part of the system undetectable for defects during a certain time interval.
    For an acoustic test of the system, illustrated in Fig. 3, a test signal is sent by amplifier module 1 on one loudspeaker circuit 30 (LSI). This signal is acoustically transmitted (31) by the loudspeakers of loudspeaker circuit LSI. At the same time, the other speaker circuit is switched off (switch SW3 open). The loudspeakers in the loudspeaker circuit (LS2) serve as an electrodynamic microphone (the same as for the sound measurement) whereby the acoustic signal 31 is converted into an electrical signal 32 present on the loudspeaker line due to the high line impedance because the amplifier is not connected to the speaker line. The signal arrives at the measuring circuit V3 where it can be compared with signal V2. The ratio between V3 and V2 is defined at the installation of the system and stored in the processing unit. The obtained ratio between the transmitted signal V2 and the received signal V3 is checked against the stored ratio every time an acoustic test is performed. If the measured ratio matches the stored value, the acoustic path still works as expected. The same measurement can be performed redundantly on the side of the amplifier module 2 with measuring circuits V6 and V5. The transmitted electrical signal from amplifier module 1 (33) is measured on measuring means V6 and the converted acoustic signal to electrical signal 32 is measured with measuring means V5.
    The other amplifier and speaker circuit can also be measured by sending from amplifier 2 via LS2 and picking up the acoustic signal with LSI.
    Although the invention has been illustrated and described in detail in the drawings and foregoing description, such illustrations and descriptions are to be considered as illustrative or exemplary and not restrictive. The foregoing description explains certain embodiments of the invention in detail. It should be noted, however, that no matter how detailed the foregoing has been incorporated into the text, the invention may be practiced in many ways. The invention is not limited to the disclosed embodiments.
    Other variations on the disclosed embodiments may be understood and performed by persons skilled in the art and by practicing the claimed invention, through a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps and the indefinite article "a" does not exclude a plural. A single processor or other unit can perform the functions of different items in the claims. The mere fact that certain measures are listed in mutually different dependent claims does not mean that a combination of those measures cannot be used to benefit. A computer program can be stored / distributed on a suitable medium, such as an optical storage medium or semiconductor medium supplied with or as part of other hardware, but can also be distributed in other forms, such as via the internet or other wired or wireless telecommunication systems. Any references in the claims should not be construed as limiting the scope.
    权利要求:
    Claims (11)
    [1]
    CONCLUSIONS
    A public address system comprising a first (1) and a second (1 ') amplifier module, each comprising an amplifier means (2, 2') and adapted to receive the same given signal to be applied to said amplifier means and to send an amplified signal , wherein said first and second amplifier modules are interconnected via a first (LSI) and second (LS2) circuit, wherein at least said first or said second circuit comprises at least one loudspeaker (11, 11 '), said first circuit being arranged to supplying said amplified signal from said first amplifier module to said second amplifier module and said second circuit being arranged to provide said amplified signal from said second amplifier module to said first amplifier module, said first and second amplifier modules further comprising analysis means for comparing pairs of signals which are selected from said received given sign al, said amplified signal output from the amplifier means included in the amplifier module and said amplified signal from the other amplifier module and sent via said first or said second circuit, and to provide an indication of the operational on the basis of said comparisons status of the broadcasting system.
    [2]
    The broadcast system of claim 1, wherein a first switch (SW1, SW3) is provided in each amplifier module, arranged to prevent the amplified signal from passing on to the other amplifier module.
    [3]
    The broadcast system of claim 2, wherein said first switch is implemented in each amplifier module as a high impedance state of said amplifier means.
    [4]
    A broadcast system according to claim 2 or 3, wherein in each amplifier module a second switch (SW2, SW4) is provided between an output of said amplifier means of the own amplifier module and an input adapted to receive the amplified signal from the other amplifier module.
    [5]
    A broadcast system according to any of the preceding claims, further comprising communication means for communicating measurement results between said first and said second amplifier module, wherein said measurements are provided by said analysis means.
    [6]
    A broadcast system according to any one of the preceding claims, wherein said analyzing means are arranged in each amplifier module to compare said received given signal with said amplified signal, to compare said received given signal with said amplified signal from the other amplifier module and to said amplified signal to compare with said amplified signal from the other amplifier module.
    [7]
    A broadcast system according to any of the preceding claims, further adapted to perform current measurements.
    [8]
    A public address system according to any of claims 2 to 7, wherein said first and second amplifier module each contain said analysis means and said first and second circuit each contain at least one loudspeaker (11, 11 ') wherein said analysis means (6,6') are positioned between said first switch (SW1, SW3) and said at least one loudspeaker of said first and second circuit, such that the broadcasting system is arranged to compare measurements of ambient noise made on said first and said second circuit.
    [9]
    A public address system according to any one of the preceding claims, adapted to generate a test signal for acoustic verification of said at least one loudspeaker and / or said amplifier means.
    [10]
    The public address system of claim 9, adapted to perform said acoustic verification in real time.
    [11]
    A method for verifying the operation of amplifier means and speakers in a broadcast system comprising a first and a second amplifier module, each comprising an amplifier means (2, 2 '), said first and second amplifier module being interconnected via a first (LSI) and second (LS2) circuit, wherein at least said first or said second circuit comprises at least one loudspeaker (11; 11 '), the method comprising the steps of: - applying the same signal to said first and second amplifier module, - the sending the signals amplified by said amplifier means from said amplifier modules via said first and second circuits to the respective other amplifier module, - comparing, in each amplifier module, signal pairs selected from said applied signal, said amplified signal output from said amplifier means included in the amplifier module and said amplifier signal from the other amplifier module and sent via said first or said second circuit, - obtaining, based on said comparisons, an indication of the operational status of the broadcasting system.
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    同族专利:
    公开号 | 公开日
    EP2884773A1|2015-06-17|
    EP2884773B1|2017-02-15|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US7702112B2|2003-12-18|2010-04-20|Honeywell International Inc.|Intelligibility measurement of audio announcement systems|
    FR2895203B1|2005-12-21|2008-02-29|Chantiers De L Atlantique Sa|SOUND DEVICE AND SHIP COMPRISING THE DEVICE|
    AT504297B1|2006-09-28|2009-11-15|Av Digital Audio Videotechnik|METHOD AND MEASURING DEVICE FOR MONITORING SOUNDPROOFING SYSTEMS|
    DE102010028022A1|2010-04-21|2011-10-27|Robert Bosch Gmbh|Method and device for monitoring a loudspeaker line|
    法律状态:
    2018-10-18| FG| Patent granted|Effective date: 20160302 |
    2018-10-18| MM| Lapsed because of non-payment of the annual fee|Effective date: 20171231 |
    优先权:
    申请号 | 申请日 | 专利标题
    EP13196359.7|2013-12-10|
    EP13196359.7A|EP2884773B1|2013-12-10|2013-12-10|Public address system and method|
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