FR2782866A1 - Local radio link parameter adaptation device for office equipment communication, modifies link parameters in response to sensed proximity of equipment user - Google Patents

Abstract

A radio module (110) associated with a photocopier (100), receives signals over an interface such as an Ethernet (RTM) connection (108, 109) from sensors in the copier. These indicate the presence of a user, such as keyboard or touch-screen input, cover position, or original presence. In response to these conditions one or more parameters such as power, frequency band, modulation type or index, or spread spectrum characteristics, are changed for a fixed duration, after which all parameters revert to their initial values. Independent claims are included for a method of parameter modification in a radio link, a network using the invention, and for equipment incorporating the device of the invention, including a computer, a copier, a facsimile, a printer, a scanner, a camera, and an information terminal.

Description

The present invention relates to a method and a device for adaptation

  radio transmission parameters, depending on the environment. The invention applies, in particular, to office automation devices such as photocopiers, fax machines, printers, equipped with an antenna and with a device for transmitting and receiving radio messages. Document printing commands can therefore be carried out remotely from a

  computer, but on condition that the radio link is of good quality.

  In an office environment, the propagation and attenuation characteristics of electromagnetic waves are constantly changing. The movement of an individual in the vicinity of an antenna modifies the propagation characteristics and cause attenuations. This problem is all the more annoying since the apparatus comprising the antenna is a photocopier, a fax machine or a printer. Indeed, a large number of users periodically come close to this type of device and can, therefore, disrupt the radio link, or even prevent any communication. Such devices are therefore permanently subjected to

  significant variations in reception conditions.

  A first solution would consist in carrying out a transmission at low speed with a very large number of redundancies, so as to compensate for the loss of information linked to the modification of the channel. However, this technique does not allow full use of the resources of the transmission channel. Multiple methods, such as those disclosed in patents W09004293 and US4696027, describe devices measuring the state of the channel

  in order to modify at least one radio transmission parameter.

  Patent WO9004293 describes a system, in this case a portable telephone which, depending on the geographic location in which the device is located, modifies one of the transmission parameters. These parameters include, among others, the transmission power, the carrier frequency, the modulation type, the modulation index, the channel spacing. Geographical location information can be obtained using a Global Positioning System (GPS) system for global positioning system). For example in cities, an area presumed to be densely populated, the power emitted is reduced so as not to disturb other terminals. On the other hand, in the more desert areas, the power is maximum to benefit from a long range. This technique is absolutely not applicable to office automation devices which are fixed, and whose operating conditions are not sensitive to places

particular geographic areas.

  Patent US4696027 describes a radio system which, by measuring the level of the signal emanating from a first radio device, gives information to the transmitter which modifies the transmission power. This type of system solves multiple problems, including interference problems between mobile phones, but its implementation is expensive. Indeed, it is necessary to add a means of evaluating the received power, as well as a means of modifying the transmitted power. Furthermore, by reducing the transmission power, this device does not improve the quality of the radio link since the power received

becomes weaker.

  Finally, many patents relate to the detection of individuals for alarm systems. In addition, inventions also use the sensors of office automation devices, but only for the purpose of controlling the use of these devices (counting sheets, checking access rights, etc.). It is clear that not all of these inventions are intended

  improving the conditions for radio transmission.

  The invention aims to guarantee optimal transmission conditions for a radio device placed in an area where the characteristics of the channel vary very significantly. The radio device consists of a device

  office automation such as a photocopier, fax machine or printer.

  The method and the device which are the subject of the present invention here make it possible to overcome this problem by modifying the radio transmission parameters each time the presence of an individual near the antenna is detected. The first step of the method of the present invention consists in implementing the detection of a person by means of the existing sensors on an office automation device (pressing of the keys of the keyboard, movement of the drawers or of the cover, etc.). Then, the device adapts the radio transmission parameters (transmission power, type or modulation index, etc.) so as to guarantee good radio link quality. The implementation of the invention amounts to anticipating and thus avoiding a

  possible deterioration of the state of the transmission channel.

  The present invention thus has a simple and inexpensive implementation since it uses already existing sensors on an office automation device, and it requires only a modification of the software controlling this.

same device.

  According to a first aspect, the present invention relates to a device for adapting radio transmission parameters of a radio transmission means, device associated with equipment comprising sensors, characterized in that it comprises: - an estimation means presence of a user, adapted to take into account the signals coming out of said sensors, and - a means for modifying the radio transmission parameter of said transmission means as a function of the presence estimation carried out by said

means of estimation.

  Thanks to these provisions, when, by deduction concerning the state of the sensors, it is considered that it is probable that a user is in the vicinity of the radio transmission means, at least one radio transmission parameter is adapted so that the user-induced mitigation either

less partially, compensated.

  According to particular characteristics, the device as succinctly described above comprises a means of determining an elapsed time after a modification of the radio transmission parameter by the modification means, said modification means being adapted, when said duration has elapsed , to return to each parameter its initial value, initial value which preceded the modification resulting from the estimation of the presence of a user. Thanks to these provisions, the radio transmission parameters are returned to their initial state after a delay which corresponds (that is to say is at least equal) to the probable presence delay of the user near

office equipment.

  According to particular characteristics, said sensors comprise: a keyboard, - a touch screen, - a cover position sensor, a sensor for the presence of sheet in a feed tray, - a sensor for the presence of sheet in an output tray sheet, - a sheet presence sensor in a document feeder to copy, and / or

  - a sheet presence sensor blocked in the sheet path.

  - Thanks to these provisions, the present invention is particularly easy to implement since all the sensors mentioned above are

  of known type and are already used in office equipment.

  - According to particular characteristics, the transmission means is adapted so that: - at least one radio transmission power used, is modified - at least one radio frequency band used is modified, - at least one type of modulation used either modified, - at least one modulation index is modified, - at least one spectrum spreading factor is modified, - at least one frequency hopping sequence is modified, - at least one equalization of the spectrum on reception, equalization implemented by said filter, either modified, and / or - at least one type of error correction code is modified. Thanks to these provisions, the implementation of the present invention is particularly efficient and uses known radio components and systems. According to a second aspect, the present invention relates to a method for adapting radio transmission parameters of a radio transmission means, a device associated with equipment comprising sensors, characterized in that it comprises: a step of estimating presence of a user during which the signals coming out of said sensors are taken into account, and - a step of determining the radio transmission parameter of said transmission means taking account of the presence estimation carried out at

during the estimation stage.

  The invention also relates to a network, a computer, a copier, a fax machine, a printer, a scanner, a camera and an information terminal characterized in that they comprise a device such as

succinctly set out above.

  The invention also relates to: - a means of storing information readable by a computer or a microprocessor retaining instructions of a computer program characterized in that it allows the implementation of the method of the invention as briefly described above, and - a means of storing information removable, partially or totally, and readable by a computer or a microprocessor retaining instructions of a computer program characterized in that it allows the implementation of the method of invention as succinctly set forth above. The preferential or particular characteristics, and the advantages of this device, this network, this computer, this copier, this fax machine, this printer, this scanner, this camera, this information terminal and these as the information storage means are identical to those of the method as succinctly explained above, these advantages are not repeated here. Other advantages, aims and characteristics of the present invention

  will emerge from the description which follows, made with reference to the appended drawings, in

  which: - Figure 1 shows a block diagram of a copier and the associated radio module, - Figure 2 shows, schematically, an electronic circuit incorporated in the device illustrated in Figure 1, - Figure 3 shows, schematically, a system of communication implementing the present invention, - figure 4 represents, diagrammatically, a circuit incorporated in the system illustrated in figure 3 and in radio communication with the circuit illustrated in figure 2, - figure 5 represents a flowchart of the under program put in work by the circuit illustrated in figure 2, and - figure 6 represents a flowchart of the subroutine implemented

  work by the circuit illustrated in figure 4.

  FIG. 1 is an overall view of a multifunction copier 100 equipped with an external radio module 110, provided with an antenna 111. The copier 100 has an Ethernet connector 108 and is connected to the Ethernet connector of the radio module 110 by an Ethemet 109 cable. The electronic circuit incorporated in

  this device is shown in more detail in FIG. 2.

  FIG. 1 uses known sensors, used for the detection of a person near the device: - a keyboard 104, - a touch screen display 103, - a cover position sensor (not shown), - a sheet presence sensor in a input tray, - a sheet presence sensor in a sheet output tray, - a sheet presence sensor in a document feeder to be copied, and - a sheet presence sensor blocked in each sheet path,

  whether this path is that of the original documents or that of the copies.

  Indeed, pressing a key on a keyboard 104 or on a touch screen 103, opening a cover 105, the presence of a document to be copied in a path passage corresponding to manual feeding 106 and the presence of sheets in a feeder placed on the cover 105, directly indicate the presence of a person, Similarly, the detection of a paper jam by the sensors placed inside the copier 100 indicates the upcoming presence of a person at

proximity to copier 100.

  In fact, if a paper jam occurs during a print job, there is a good chance that someone will come quickly to the copier to remove the jammed sheet. Likewise, the indication of the absence of paper in the feed trays, by the appropriate sensors, provides information on the imminent presence of a person, as well as the presence of sheets

in the output bin 102.

  In the embodiment described and shown, the invention applies to the copier 100. The copier 100 comprises a main data processing circuit 203, associated with a read-only memory 201 and a random access memory 202. The read-only memory 201 contains operating programs of the main processing circuit 203, while the random access memory temporarily stores the data received from the radio module 110 via the interfaces 211 and 221, as well as the data processed by the main processing circuit 203. The main processing circuit 203 is connected to the touch screen display 103 on which it controls the display of representative messages

copier status 100.

  The main processing circuit 203 is also connected to a keyboard 104, comprising at least one switch, with which the user can transmit

  operating commands to copier 100.

  The main processing circuit 203 is connected to the electromechanical members 210 of the copier 100, via interfaces 206, 207

and 208.

  The interface 208 allows the main processing circuit 203 to control motors (not shown) which transport the sheets and

  which drive the moving parts necessary for the operation of the copier 100.

  The interface 208 also makes it possible to connect the main processing circuit 203 to the sensors which inform it of the state of the copier. The copier also has: - a print controller 206 which allows the main processing circuit 203 to control the electromechanical components 210 responsible for printing, and - a controller 207 which allows the main processing circuit 203 to control the electromechanical components 210 responsible for image acquisition. The copier 100 receives data to be printed via radio equipment 110. These two devices 100 and 110 have

  compatible interfaces 211 and 221 which allow them to exchange data.

  The radio equipment 110 is further composed of a main data processing circuit 222, associated with a read-only memory 226 and a random access memory 227. The read-only memory 226 contains operating programs of the main processing circuit 222, while that the random access memory 227 temporarily stores the data received from another analog radio module 302 (FIGS. 3 and 4), as well as the data processed by the circuit

principal of treatment 222.

  The main processing circuit 222 is connected to an analog-digital converter 228, which quantifies the level of the radio signal received. The main data processing circuit 222 is connected to a modulation and demodulation circuit 223, converting the streams of binary information into analog signals. The modulation and demodulation circuit 223 is connected to an RF stage 224 which ensures the amplification of the signals and their transposition in frequency. Finally the RF stage 224 uses an antenna 111 to

  receive and transmit radio waves.

  The copier 100 and the radio equipment 110 previously described are conventional and well known to those skilled in the art. They will therefore not be more

detailed here.

  Figure 3 shows an overall diagram for carrying out the invention. Two analog radio devices 302 and 110 allow to do

  communicate a PC 301 and a copier 100 using a radio channel.

  The exchange of data can be done bidirectionally, the radio equipment is in turn transmitter or receiver. This assembly allows

  to carry out printing applications.

  With reference to FIG. 3, it is convenient to arbitrarily call the radio equipment 302 connected to the PC: the base, and the radio equipment 110

connected to the copier: the station.

  According to variants not shown, the radio equipment 302 is incorporated into the computer 301 and / or the radio equipment 110 is incorporated into

office equipment 100.

  In the figure, 4 are represented the main components of an electronic device 301 implementing the present invention. This device 301 has an architecture known in the field of programmable electronic systems, based on the use of components connected between

  them by a bus 405 and a central unit 401.

  For example, these elements are found together associated in a personal computer, of a known type, for example of the type operating with a microprocessor 401 PENTIUMTM from the company INTELTM, which comprises at least a random access memory RAM 403, a non-volatile memory ROM 402, a

  screen 408, a mouse 407 and a keyboard 406.

  An input / output port 404 receives digital information from the user, via the keyboard 406, the mouse 407 or any other means of communication, and transmits it, under the control of

  the central unit 401, to a random access memory RAM 403.

  In addition, the input / output port 404 transmits, under the control of the central unit 401, to the screen 408 the data intended to be displayed. The input / output port 404 is also associated with a radio module 412. The latter makes it possible to send and receive data to the printing device 100

  which also has its own radio module 110 (Figure 3).

  RAM memory 403, of known type, comprises registers intended to receive parameters, variables, digital data and

  intermediate processing values.

  The non-volatile memory 402, of a well known type, retains the program which allows the device to operate and, in particular to

the central unit 401.

  The radio equipment 302 is further composed of a main data processing circuit 422, associated with a read only memory 426 and a random access memory 427. The read only memory 426 contains operating programs of the main processing circuit 422, while the random access memory 427 temporarily stores the data received from another similar radio module 110 (FIGS. 2 and 3), as well as the data processed by the circuit

main processing unit 422.

  The main data processing circuit 422 is connected to a modulation and demodulation circuit 423, converting the information streams

binary in analog signals.

  The modulation and demodulation circuit 423 is connected to an RF stage 424 which ensures the amplification of the signals and their transposition in frequency. Finally the RF stage 424 uses an antenna 425 to receive and

transmit radio waves.

  FIG. 5 shows the flowchart of the subprogram resident in the copier's read-only memory and implementing the method of the present

invention.

  In FIG. 5, it can be seen that the first operation 501 of the subroutine consists in reading the values of all the sensors of the copier useful for detecting a person nearby: pressing on the keyboard 104 and / or the touch screen display. 103, error message (paper jam), no paper in the feed trays, presence of sheets in the feeder and in the output tray (photocopy), open or closed status of the drawers, manual feed, of the cover. These values from the sensors are stored in RAM in the form of a table and constitute the reference values, operation 502. This operation is then repeated: new values are read from the sensors, operation 503, and stored in RAM in a second table, operation 504. During a test 505, the new values are compared with the values

reference.

  In addition, the new values representing the new references, they are copied in the first table, during operation 503, before

  read other new values.

  If the result of test 505 is negative, operations 503 to 505 are repeated, storing the values measured in the second table until the

  detection of a change (positive test result 505).

  If one of the values has changed, when the result of the 505 test is positive, it means that it is likely that a person is near the copier. When it is believed that a person has been detected, during a test 506, it is determined whether a radio transmission is in progress to determine whether it is necessary to modify the radio transmission parameters. When the result of test 506 is negative, that is to say in the absence of radio traffic, we

  does not change the parameters and operations 503 to 506 are repeated.

  Otherwise, result of test 506 positive, during an operation 507, the station 110 is sent the order to modify the radio transmission parameters and, during an operation 508, the order to inform the base

302 of these changes.

  Then, during an operation 509, a clock pulse counter is initialized with a duration sufficient to estimate that the person is no longer close to the copier (for example 5 minutes) . A down counter value test 510 becomes positive at the end of the timer, that is to say that the counting of the initial number of clock pulses has been completed, the station is instructed to resume its parameters of radio transmission by default, as well as the order to inform the base, operation 511. The countdown time for the down-counter is a period of about two minutes which represents the average duration of presence of a person near the

copier 100.

  According to a variant not shown, each type of sensor is associated with a predetermined duration, to take into account the fact that a person spends more time near the copier in the event of jamming than in the event

  there is no paper in the input tray.

  Finally, during an operation 512, we send the parameters of

  radio transmission by default, before repeating operation 501.

  FIG. 6 illustrates the flow diagram of the subroutine resident in read-only memory of the associated transmission-reception system (radio equipment 302). This subroutine is executed when the radio equipment 302 receives a radio message or an Ethernet message. It allows the radio equipment 302 to modify its radio transmission parameters if it has received the order. We give

  here an example where the modified parameter is the transmission power.

  In the embodiment described and shown, the transmission power is, in fact, increased when the presence of a person near

of copier 100 is determined.

  Once the message has been received and decrypted, during one of the operations 601 (messages on Ethernet port) or 602 (radio message), during a test 603, it is determined whether one of the messages is a message of modification of radio parameters. In the event of a request to modify the radio transmission parameters, result of test 603, we pass to the high power transmission mode (by activation of a switch not shown),

  during an operation 604, then operation 601 is repeated.

  When the result of test 603 is negative, during a test 605, it is determined whether one of the messages is a message returning to the radio default settings. When the result of test 605 is negative, operation 601 is repeated. When the result of test 605 is positive, during an operation 606, the transmission power will be fixed at the low level by default (by returning to the original position of the switch activated during operation 604. Then

operation 601 is repeated.

  In the embodiment described and shown, the radio communication is bidirectional and symmetrical. Also, each modification of the transmission parameter on the 302 base is accompanied by the same

  modification applied to station 110, and vice versa.

  In variants not shown, other radio transmission parameters are modified when it is estimated that a person is close to the office equipment to which the present invention applies. These parameters are: - the frequency band used, - the type of modulation, amplitude, frequency or phase, - the modulation index, - the spread spectrum factor, in the case of a transmission with spread spectrum, - the number of frequency hops in the case of a transmission with spread spectrum by frequency hopping, - the frequency hopping sequence in the case of a transmission with spread spectrum by frequency hopping, - I 'spectrum equalization on reception (using an adaptive filter), and

  - the type of error correction code.

Claims (26)

  1. Device for adapting radio transmission parameters of a radio transmission means (110), device associated with equipment (100) comprising sensors (102 to 106), characterized in that it comprises: a means of estimation (201 to 203) of the presence of a user, adapted to take into account the signals coming out of said sensors, and - a means of modification of parameter (201 to 203) of radio transmission of said means of transmission as a function of the presence estimate   performed by said estimation means.   2. Parameter adaptation device according to claim 1, characterized in that it comprises a means for determining (201 to 203) of an elapsed time after a modification of the radio transmission parameter by the modification means, said means modification (201 to 203) being adapted, when said duration has elapsed, to return to each parameter its initial value, initial value which preceded the modification resulting from the presence estimate of a user.   3. Device according to any one of claims 1 or 2,   characterized in that said sensors include a keyboard (104).   4. Device according to any one of claims 1 to 3, characterized   in that said sensors include a touch screen (103).   5. Device according to any one of claims 1 to 4, characterized   in that said sensors include a cover position sensor (105).   6. Device according to any one of claims I to 5, characterized   in that said sensors include a sheet presence sensor in a feed tank (106).   7. Device according to any one of claims 1 to 6, characterized   in that said sensors include a sheet presence sensor in a sheet output tray (102).   8. Device according to any one of claims 1 to 7, characterized   in that said sensors include a sheet presence sensor in a document feeder to copy.   9. Device according to any one of claims 1 to 8, characterized   in that said sensors include a sheet presence sensor blocked in the sheet path.   10. Device according to any one of claims 1 to 9,   characterized in that the parameter modification means is adapted to this   at least one radio transmission power used is modified.   He. Device according to any one of Claims 1 to 10,   characterized in that the parameter modification means is adapted to this   at least one radio frequency band used is changed.   12. Device according to any one of claims 1 to 1 1,   characterized in that the parameter modification means is adapted to this   at least one type of modulation used is modified.   13. Device according to any one of claims 1 to 12,   characterized in that the parameter modification means is adapted to this   at least one modulation index is changed.   14. Device according to any one of claims 1 to 13,   characterized in that the parameter modification means is adapted to this   at least one spread spectrum factor is changed.   15. Device according to any one of claims 1 to 14,   characterized in that the parameter modification means is adapted to this   at least one frequency hopping sequence is changed.   16. Device according to any one of claims 1 to 15,   characterized in that it comprises an adaptive filter and in that the parameter modification means is adapted so that at least one equalization of the   spectrum on reception, equalization implemented by said filter, is modified.   17. Device according to any one of claims 1 to 16,   characterized in that the parameter modification means is adapted to this   at least one type of error correction code is changed.   18. Method for adapting radio transmission parameters of a radio transmission means (110) associated with equipment (100) comprising sensors, characterized in that it comprises: - a presence estimation step (503 to 505) of a user during which the signals leaving said sensors are taken into account, and - a step of determining the parameter (507) of radio transmission of said transmission means taking account of the presence estimate   performed during the estimation stage.   19. A method of adapting parameters according to claim 18, characterized in that it comprises: - a step of determining an elapsed time (509, 510) after an operation to modify the radio transmission parameter, and when the step for determining the duration flow indicates that said duration has elapsed, - a step for resetting parameters (511, 512), during which, for each parameter modified during the modification step, its   initial value, which preceded the modification step.   20. Network, characterized in that it comprises a device according to one   any of claims 1 to 17.   21. Computer, characterized in that it comprises a device according to one   any of claims 1 to 17.   22. Copier, characterized in that it comprises a device according to one   any of claims 1 to 17.   23. Fax machine, characterized in that it comprises a device according to one   any of claims 1 to 17.   24. Printer, characterized in that it comprises a device according to   Any of claims 1 to 17.   25. Scanner, characterized in that it comprises a device according to one   any of claims 1 to 17.   26. Camera, characterized in that it comprises a device according to one   any of claims 1 to 17.   27. Information terminal, characterized in that it includes a device   according to any one of claims 1 to 17.