Patent Application
20130119133
This invention relates to:
Machine readable bar codes representing digital data and printed or marked directly on labels, packaging, or products are known and are currently being used to provide a product or document identification based on a fixed set of code-marks in connection with coding and scanning technologies. Bar codes can be designed in very different ways, also in two-dimensional patterns. However, all these variations have one thing in common: they are visual representations of codes that have to be read optically, i.e. the code has to be printed or made visible on a screen, and in order to read the code an optical scanner or camera is necessary.
Many devices, especially portable devices, have an audio output component designed for generating voice signals which can be perceived by human users. A wide range of input components is in use: keys, microphone, touch screen, camera, sensors or special scanners in various forms.
A solution based exclusively on acoustic signals requires that the input signals also be in acoustic form. In this context a bar code would have to be replaced by an acoustically modulated data signal. A receiving unit which is designed for acoustical input and output requires no additional optical scanning component. If a communication channel for audible signals is provided it can be used to transmit acoustically modulated data signals.
The task addressed by the present invention is to establish a method which enables a purely acoustic interaction between one of many participants through their individual receiving unit and a station which is assigned to one of many objects. Further the present invention comprises means by which said method can be implemented.
Said task is solved by a method which identifies objects and triggers interactions. Said method features an acoustically modulated data signal sent from a station whereby both the said data signal and the said station are associated with an object. Said method further features the identification of the line connecting the receiving unit with the processing point through which said data signal is transmitted. Content which is associated with said object is then transmitted through said line from said processing point to said receiving unit. Thus an interaction regarding one of many said objects is enabled between one of many participants and said processing point via the participant's said receiving unit.
Furthermore said task is solved by identifying objects and triggering desired interactions using acoustically modulated data signals comprising:
This invention, its method and means and their function will be explained in detail with the help of the attached diagrams and drawings. This will illustrate the range of possible applications, achievable results, advantages and characteristics of the invention:
In a first step, the basic differences between an optical and an acoustical barcode will be addressed:
The principals of transmitting data through a line using audible signals is prior art and well known from the technology of acoustic couplers. Most Applications deal with machine-to-machine communication, such as the communication between fax machines or between terminal and computer, using phone lines and ordinary telephones.
The fundamental differences between acoustic coupling as used in prior art and as used with Acoustical Bar Codes in the present invention will now be described in some detail.
An object 2 is identified by identifying the acoustically modulated data signal 4e associated according to 105. This occurs with means as shown in
From the sequence of the different acoustically modulated data signals 4e received via the transmission path (117, 5, 116, 14 and 113), the movement of a portable receiving unit 3 relative to the stations 4 implicated in its interactions can be determined.
In addition to the transmission path (117, 5, 116, 14 and 113) via the receiving units 3, the stations 4 can be connected directly to the processing point 9 using an additional path (106, 6 and 107). This additional direct communication path has the following advantages:
From the description above, three sets of issues of great importance for this invention result:
The interactive solutions described here can provide information, guidance or navigation and can find applications in museums, collections, exhibitions, tutorial paths, sight-seeing tours, historic locations, monuments, viewpoints, tutorials, in retail business (shops, shopping malls, vending machines), in important buildings, airports and train stations as means of information, orientation, etc. This list of application areas is by no means exhaustive, and numerous other application areas can be envisaged. The core feature and the specific characteristics of this technology will always be the identification of objects and the triggering of desired interactions by means of close-range coupling of acoustically modulated data signals. Applications are also possible where input signals are fed electrically e.g. using the electrical interface of a hands-free set in a portable receiving unit.
In the following the invention, and in particular the aspect of interactive systems, will be illustrated using the special case of audio guides for museums and retail stores, and of cell phones as receiving units, as an example.
Most museum visitors appreciate being guided through an exhibition. Conventional methods are guided tours with an expert or guide books and brochures. Experts are expensive and not always available, while walking through an exhibition reading a guide book or written comments has the disadvantage that the visitor has to constantly switch his attention between the written explanations and the exhibits—a notoriously tiring and distracting behaviour.
Guided tours with small audio devices have therefore become widespread. Their advantage is that visitors can enjoy spoken commentaries in their preferred language at any time. This way they can concentrate on the exhibits without having to read constantly. A disadvantage is these portable audio devices are expensive, and have to be serviced on a daily basis. The number of portable audio devices which have to be provided has to be equal to the maximum number of visitors who may attend the exhibition simultaneously, plus the number of devices being cleaned and recharged after use.
Visitors in a retail store or a shopping mall would like to be informed about products on offer—an important measure in increasing sales. Most shops inform their visitors acoustically through the shop's public address system. This informs all visitors at the same time rather than individually. The advantage is that of a simple and relatively inexpensive solution, but the disadvantages are often poor speech intelligibility and the lack of any possibility of informing customers individually. Visitors cannot access information in accordance with their specific needs; they cannot be addressed according to their individual customer profile; and there is no way to gather information for the purpose of customer profiling.
Cell phone based systems which are key, speech or touch-screen controlled or which work in connection with GPS data, smart phone cameras and/or pattern recognition etc. are prior art (e.g. cell phone tours). Their operation confronts the users with:
This invention introduces a new kind of interaction which overcomes the above disadvantages. It offers a cell phone based interaction suited for any cell phone, no matter of which type, independently of any special technical feature, while providing a very simple, basic and robust interaction.
If e.g. a cell phone tour (guided tour based on cell phones) is offered for an exhibition, the visitors dial the exhibition's service number, and then enters an additional code every time he wishes to hear the information sound track associated to a given exhibit. This imposed behavior is both inconvenient and distracting. The visitor must enter a code for each exhibit for which a sound track is desired; he must divide his attention between exhibits and cell phone; and he must do so under the often poor lighting conditions of exhibitions in which lighting is concentrated only on the exhibits themselves.
The solution based on this invention sets itself apart from conventional cell phone tours in particular because here data is transmitted acoustically (acoustically modulated data signals) from a cell phone to the processing point using the normal speech channel. This makes the service significantly more convenient to use, as no data has to be entered using keys or the smart phone camera etc. Mistakes made when entering the wrong code, as are common when using keypads or voice control, are eliminated. This simplified interaction makes the system very attractive for visitors.
In the following an interactive system is described according to
All active cell phones 3 pick up ambient noise and other acoustic signals and constantly transmit them to the processing point 9 making the task of detection more difficult. There is a probability that these interfering signals can be erroneously recognised as an acoustically modulated data signal, thus triggering an unwanted interaction.
The acoustically modulated data signals 4e need to be designed specifically in such a way that the probability of being simulated by speech, singing, noise, sound, etc is very low. This is done by giving the signals 4e characteristics (amplitude range, signal frequency, signal duration, sequence of these characteristics, signal redundancy, time stamp) which can be verified in the process of detection 11. Suitable measures for designing signals for very reliable detection and a low probability of mis-detection are known from coding theory and can be applied selectively, also taking into account the properties of the interfering signals.
If cell phones are being used as mobile receiving units 3 the particular specifications of the mobile phone system also have to be taken into consideration.
In a mobile phone network the speech channel is the only easily accessible and open transmission channel, whereas dedicated and general-purpose data channels are frequently not accessible, are not implemented, and/or require an inconvenient interaction with the user 1.
The present solution features an acoustically modulated data signal 4e consisting of a sequence of superimposed oscillations. As this data signal has to be transmitted through the speech channel of the phone network the frequencies that are being transmitted have to lie within the transmittable range, i.e. between 300 Hz and 3′400 Hz.
Because the frequencies of the human voice as well as of ambient noise also lie within this range there is, as mentioned previously, the risk that such signals might be mis-interpreted as a full data signal 4e or at least as a part of it.
With this in mind, for example, the DTMF-system (Dual Tone Multi Frequency) which has been known for many years in telephony (ETSI ES 201 235-1 Specification of Dual Tone Multi Frequency (DTMF)—Transmitters and Receivers; Part 1: General) has the following behaviour:
The DTMF-system comprises on the side of the transmitter a DTMF tone generator and on the side of the receiver a DTMF decoder. The generator is controlled by the phone key. The receiver consists of an electronic circuit devised to detect DTMF frequencies and a program which reconstructs the transmitted codes from the properties of the detected signals. The signals consist of two short simultaneous and superimposed signal sequences each one of which is selected from two separate groups, a low group (697 Hz, 770 Hz, 852 Hz and 941 Hz) and a high group (1209 Hz, 1336 Hz, 1477 Hz and 1633 Hz), each group providing four signaling frequencies in the middle range of speech frequencies.
In contrast with the DTMF system, which can only transmit either speech signals or DTMF signals at any given time, externally generated acoustically modulated data signals and/or noise can be transmitted simultaneously when using cell phone. There is no clear specification for the reliable detection of DTMF signals by a common DTMF receiver in the presence of speech or noise at significant levels. This means that conventional DTMF receivers can not be used under these circumstances.
There are further arguments against using conventional DTMF signals. The specified frequencies were chosen as a set of numbers that are as mutually incommensurate to each other as possible, in order to avoid interference caused by harmonic components. This means that signal sections including frequency tolerances can not have a common period. Assembling signals from pre-recorded digital signal components of finite and constant length is therefore frequently associated with discontinuities in amplitude. Furthermore a detection of DTMF signals based on a short-term discrete Fourier Transformation delivers frequency values which do not correspond to the DTMF frequencies themselves, which in turn leads to systematic measuring errors. When detecting signal frequencies over finite measuring intervals (not only but especially when using correlation detection) interfering products result. Finally transmission errors can lead to the repetition by the transmission channel of the mobile telephone network of single frames (these are sequences of samples e.g. 160 samples or 20 milliseconds with GSM). This causes signal discontinuities, generally connected to phase jumps, which can interfere massively with a correlation detection or detection with Goertzel Filters as commonly used in DTMF technology.
As, for the above reasons, existing DTMF technology is not suited for acoustic coupling, a proprietary system of frequencies and patters has been developed for the acoustically modulated data signals, which is part of this invention and is explained in
It makes sense to use a new set of frequencies which are multiples of a basic frequency. This allows simple generation and switching in a fine time grid avoiding amplitude jumps. If in addition the basic frequency is equal to or a multiple of the frame frequency, repeating a frame will not cause a phase jump. Furthermore when detecting the frequency components of the data signal, detection components from other system frequencies will be exactly zero at the end of the frames, which in turn significantly increases the reliability of the detection.
With a frame frequency of 50 Hz which corresponds to a frame length of 20 milliseconds, the above considerations lead to alternatives to the DTMF frequencies using a grid based on frequencies of 50 Hz, 100 Hz, 150 Hz, etc. Instead of using the hitherto existing DTMF frequencies e.g. the following new DDTMF frequencies could be used:
Further improvements are possible using DTMF-like signals. It is advantageous for example if the various possible frequency components of a signal are chosen as far apart from each other as possible. Instead of working with two superimposed frequencies, one chosen from a low group of 4 and one from a high group of 4, according to the DTMF principle, i.e. with code values according to 21 and frequency assignments according to 22 and 23, it is more advantageous to avoid combinations of high frequencies of the low group with low frequencies of the high group as is the case e.g. with frequency assignments according to 25 and 26 and a reduced assignment of value pairs to codes according to 24. It becomes apparent that deliberately imposing this restriction on the set of transferable signals which is 16 with DTMF will reduce our new set to exactly 10. This simplifies the use of the described technology for applications which are based on decimally defined data which can be found e.g. with many conventional bar codes as well as PIN codes, whereas conventional DTMF technology is basically hexadecimal. In our case, a well-justified reduction of the set of signals is achieved not through randomly or arbitrarily omitting certain frequency combinations as in the case of DTMF where e.g. the signals A, B, C, D as well as * and # are excluded but through a selection of signal combinations with good properties enhancing the robust detection of the signals. This choice of discrete frequencies which can be combined from two groups which have an ideally large distance between each other and specially suited for transmitting decimally coded data is illustrated in
Based on such a definition of discrete frequencies which is suited for the transmission of acoustically modulated data signals for hexadecimally or decimally coded data, it is now possible to define data formats which improve the security of data transmission. The example in
In order to make sure that a cell phone 3 is in close range of a station 4 thus reducing the probability that noise would trigger off an interaction by mistake, the presence of the phone 3 can be detected by the station 4. The information that a station 4 has detected a cell phone 3 is transmitted to the processing point 9 and used as a condition in connection with the arrival of the respective data signal to trigger off the transmission of the respective content. This can be done without a functional interaction specific to mobile telephony e.g. by activating a sensor 4c (mechanical switch, proximity switch, ultrasonic sound sensor, infrared sensor, optical sensor, capacitive or inductive detection, detection of the radiation of the receiving unit, detection with the help of radar, etc.). The combined use of different sensors 4c is also possible. If no information is provided regarding the presence of a cell phone all lines have to be monitored constantly with regards to the arrival of an acoustically modulated data signal 4e whereas if information regarding presence is gathered centrally the monitoring data signals 4e can be reduced to a short span of time slightly longer than the data signal 4e. Noise which might simulate data signals 4e appearing outside the measuring window will be suppressed effectively. It is also very advantageous that a data signal 4e has to be detected only when coming from a station 4 which has detected and signaled the presence of a cell phone. The signal which has to be detected is known a priori.
Further test procedures are possible in order to avoid a misdetection. A visitor who was detected with a high probability e.g. at exhibit No. 3 will not be able to suddenly appear 10 seconds later at exhibit No. 96 in a remote wing of the museum. The coordinates of the stations 4 and the sequence of their use can also contribute to reducing the probability of a misdetection.
The following outlines an interaction using an exhibition as an example. A visitor 1 would like to obtain spoken information 12a associated with exhibit 2 on his cell phone 3.
Close to the exhibit 2 there is a station 4 with a tone generator 4a and a sound source 4b (loudspeaker, sound transducer) which produces an acoustic signal which identifies the exhibit 2 (as well as a special form of interaction, language . . . if such features are offered). If the microphone 3a of a cell phone 3 is held close to the sound source 4b the acoustically modulated data signal 4e is transmitted to the processing point 9. There it will be recognised even in the presence of a significant level of noise. Based on the detection 11 of the specific data signal 4e and on the identity of the specific line 14 on which it has been detected, it becomes clear that visitor 1 with his cell phone 3 is specifically requesting on his line 14 the content 12a associated with the exhibit 2 and the corresponding spoken comment 12a can be transmitted. As a result, visitor 1 is supplied the desired information 12a.
It is necessary for the allocation of the data signal 4e to the line 14 to be performed reliably i.e. the correctly allocated comment 12a for an exhibit 2 has to be supplied on the correct line to the visitor 1 who has asked for this content.
Even though in many cases the system will be aware of the phone number of visitor 1 occupying line 14, explicit knowledge of this phone number is in no way required.
As it is not known, prior to the detection 11, on which line 14 the data signal will be recognised, it is necessary to constantly check all lines 14 for the possible appearance of any data signal 4e.
A station 4 can also feature a menu offering interactions for visitor 1 to choose from. This menu could be available in tactile (e.g. keys) ore virtual (e.g. touch screen) form. The menu can e.g. refer to:
In this case the station 4 serves to identify the line, and can optionally also serve to determine the actual content 12a associated with the interaction.
The following examples of applications require the stations 4 to be directly connected to the processing point 9:
A further form of interaction is e.g. a solution for customers or visitors in which a guided tour or a set of information is personalized. Here some examples:
The applications described here serve to enable interactions according to customer's requests and choices.
| Number | Date | Country | Kind |
|---|---|---|---|
| 535/10 | Apr 2010 | CH | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/CH11/00079 | 4/12/2011 | WO | 00 | 1/25/2013 |
