WO1995007516A1 - Radio transceiver for the reception and transmission of information - Google Patents

Radio transceiver for the reception and transmission of information Download PDF

Info

Publication number
WO1995007516A1
WO1995007516A1 PCT/FR1993/000858 FR9300858W WO9507516A1 WO 1995007516 A1 WO1995007516 A1 WO 1995007516A1 FR 9300858 W FR9300858 W FR 9300858W WO 9507516 A1 WO9507516 A1 WO 9507516A1
Authority
WO
WIPO (PCT)
Prior art keywords
means
information
signal
device
characterized
Prior art date
Application number
PCT/FR1993/000858
Other languages
French (fr)
Inventor
Dominique Bernard Hamel
Original Assignee
Dominique Bernard Hamel
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to FR9204013A priority Critical patent/FR2689707B1/en
Priority claimed from FR9204013A external-priority patent/FR2689707B1/en
Application filed by Dominique Bernard Hamel filed Critical Dominique Bernard Hamel
Priority to PCT/FR1993/000858 priority patent/WO1995007516A1/en
Publication of WO1995007516A1 publication Critical patent/WO1995007516A1/en

Links

Classifications

    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06KRECOGNITION OF DATA; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K19/00Record carriers for use with machines and with at least a part designed to carry digital markings
    • G06K19/06Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
    • G06K19/067Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
    • G06K19/07Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
    • G06K19/0723Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06KRECOGNITION OF DATA; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K19/00Record carriers for use with machines and with at least a part designed to carry digital markings
    • G06K19/06Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
    • G06K19/067Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
    • G06K19/07Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
    • G06K19/077Constructional details, e.g. mounting of circuits in the carrier
    • G06K19/07749Constructional details, e.g. mounting of circuits in the carrier the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card

Abstract

A radio transceiver for the reception and transmission of information is integrated in a portable object and adapted to exchange information with an information processing station, and comprises information reception and transmission means which are connected to a central processing unit (2), and an electric power supply (1), said transceiver being characterized in that it further comprises means (3) for the periodical activation of means (4) for the detection of the emission of a radioelectric signal by the information processing station whose output is connected to control means (5a) for controlling the supply to the remaining (2) elements of said device in response to the detection of the signal.

Description

'Receiving device and information by radio transmission. "

The present invention relates to a receiving device t of transmitting information by means ra- dio-electric integrated in a portable object and adapted to exchange information with an information processing station.

Of information exchange systems between portable objects and information processing stations are already known in the state of the art and have been developed to allow the exchange of information between the two bodies, without physical contact between them.

Indeed, in some applications, this physical contact is relatively restrictive.

Is known for example from document FR-A-2640830, a device for the remote exchange of information between a portable object and a station.

This device is based on the variation of an electromagnetic signal at the terminals of an inductive part of a frame, at a dis¬ tance inductive coupling with a portable object such as a card to re mémoi¬, that is meaningful to the presence of the card in the portico. Also known from the French patent application 91/11621, a device of the type described above that includes information receiving means transmitted by the station, frequency modulation, demodulation means of means output signals receiving a unit of information traite¬ ment for the treatment of informa¬ tions output of the demodulation means and a os¬ cillateur controlled by the processing unit informa¬ tion and connected to transmission means information, amplitude modulation, in the direction of the station. However, all the devices developed in the state of the art have a nom¬ ber of disadvantages in their relatively limited operational autonomy because the alimenta¬ tion into electrical energy of the different bodies of these devices is provided by example by a battery or an electrical accumulator.

The purpose of the invention to solve these problems of autonomy. To this end, the invention relates to a device for receiving and transmitting information by radio-electric means, integrated into a por¬ object tative and adapted to exchange information with an information processing station, said Avail- operative part comprising means for receiving and means connected information transmitting unit to a cen¬ tral information processing, and a source of Ĭ power supply electric power, characterized in that it comprises further periodical activation means of the emission detecting means of a radio signal by the infor¬ mation processing station, whose output is connected to the power control means of the rest of the organs of the device in response to detection of said signal. Advantageously, the activating means comprises an oscillator whose output activates a power switch of the detecting means, connected between the power source into electric power and the detecting means. Also advantageously, the means for ré¬ reception of radio-electric signal are formed by the information receiving means of the device.

The invention will be better understood 1'aide the following description, given only ti- be an example and made with reference to the accompanying drawings an¬ which:

1 shows a block diagram of one embodiment of a portion of a device according to the invention; 2 shows a detailed electrical diagram of an embodiment of the part of the positive dis¬ according to the invention, shown in Figure

1;

3 shows the pulse delivered by an operational amplifier forming part of a device according to the invention;

4 shows the signal provided by means for receiving a radio-electric signal, forming part of a device according to the invention; and

5 shows the embodiment of detection of an intermediate frequency means, en¬ trating in the constitution of a device according to the in¬ vention. As can be seen in Figure 1, a device for receiving and transmitting information by radio-electric means, integrated into a por¬ object tative and adapted to exchange information with an information processing station , in a known way comprises a power source to electrical energy, denoted by the general reference numeral 1 in this figure and constituted for example by a battery.

Furthermore, this device égale- ment comprises a number of receiving means and Ȭ mission information, connected to a central processing unit of information e.g. micropro¬ predecessor.

This all means is designated by general reference 2 in this figure.

For more information concer¬ ing the devices of this type, reference may be made to the documents mentioned above.

In contrast functions standby clock f currently-exploited by remote data transmission systems, which are based essentially on the principle of radiation of the inductive type issued by a fixed beacon, with a specific material for this function and constituted for example by a anten- not turn with a diameter of several tens of meters centi¬ and a low frequency generator exem¬ ple 100 to 200 KHz, the device according to the invention does not require other material as that used for data transmission. This is because this function veil¬ ​​the clock is filled by means of in¬ porates device in the portable object itself and that is when this device is going to activate its own initiative for the presence fixed station data trans- mission.

To perform this function, the device 1 shown in this figure further comprises means 3 for periodic activation means 4 of détec¬ tion of transmitting a radio signal by an information processing station which Sor- the tie is connected to means 5a for controlling the ali¬ mentation of the rest two bodies of the device, in response to detection of said signal.

In the embodiment shown, these activation means 3 comprise a 6 connects to the power supply source oscillator élec¬ stick 1 and whose active output periodically 7 power switch 4 detecting means mentioned above. This switch 7 is connected between the power source to electrical energy and one such means.

As shown, the means of detection 4 dé¬ aforementioned advantageously comprise means 8 for receiving the electric signal radio¬ whose output is connected to determination means 9 and of the detection means 10 of the intermediate frequency of this signal, to activate the switch 5a described above, in response to receipt of this signal.

Note that the determination of the intermediate frequency means advantageously comprise an oscillator 11 connected to an input of a mixer 12 receiving on another input, the output of the receiver means 8 consist, for example an antenna. The output of this mixer 12 is connected to a filter 13 for intermediate frequency. The output of the intermediate frequency filter may be connected to a freezer 14 démodu¬ issuing a relevant signal to the remaining organic born of this device.

The output of the frequency filter intermé¬ diary 13 is also connected to the input of detector 10 mentioned above, through an amplifier 15. It is therefore understandable that the part of this integrated tif provi- in the portable object, allows periodically testing the presence of a HF wave of predetermined frequency. The polling period depends on the type of system applications. Over the scruta- tion period and the greater autonomy tif porta¬ object increases since the bare dimi¬ consumption.

It is therefore advantageous to use the same fré¬ accordingly as used for the exchange of informa- tion.

Receiving this wave HF is carried out using a receiving circuit of this known type which will be described in detail hereinafter and which is energized at the end of each scanning period. This circuit is also used by the rest of the organs of the device for exchanging data between the information processing station and the portable object.

So as to obtain the information of the presence of an radio signal as soon as possible, that is to say to reduce the time pen¬ ing said means of reception and detection are fed in end each period and to hold ob¬ selectivity, that is to say rejection of neighboring fre- quences, sufficient, the radio¬ electrical signal is analyzed after filtering the intermediate frequency (IF) and before demodulation, that is to say, it is taken between the intermediate frequency filter 13 and the demodulator 14 to be in- ejects in the detection means 10.

For example, it turns out that activa- tion of 0.2 ms in this part of the device can be determined without fail the presence or absence of the HF wave.

The polling period can be established, depending on the application, from 0.1 s to several seconds dizai- born. The width of the window scruta¬ tion period end is not correlated to the length of this period.

Note that the detector 10 also pi- lotent a self-power switch 5b of the detection means. This switch is connected in parallel with the switch 7 described above and driven by the oscillator 6. A reset signal (RESET) of the detection means 10 is applied thereon by the CPU 2 of trai¬ ment.

It is therefore understandable that the oscillator 6 causes the periodic closure of one switch 7 for ali¬ Menter the detection means 4 of an electrical radio signal transmitted by a station. These means, in répon¬ to the detection of this signal, trigger alimen¬ tion of the rest of the organs 2 of the device by in¬ termédiaire switch 5a to allow Ȭ exchange of information between the device and the sta- tion.

In Figure 2, a detailed embodiment is shown of this portion of the device.

It is recognized in fact in this figure, the oscillator 6 which is formed around a plifica- has programmable operational tor type LM 4250 whose consumption is reduced to lμA by the resistor R4.

When the output of this amplifier is rational opé¬ to Vcc (or so), the capacitor Cl charges through resistor R5 and the fixed periodic oscillations. This resistance is set for example to 10 MOhms so as to minimize the load current of the capacitor Cl.

When the negative input of this operational tor amplifica¬ reaches the potential of the positive input, namely substantially Vcc, the output of the latter flip-flop 0, altering the potential of its positive input determined by resistors R and R2.

Meanwhile, the capacitor C is rapidly déchar¬ ge through the diode D3 become conductive trice.

When the negative input of the operational amplifier is lowered to the level of the positive input, the output of this operational amplifier toggle Vcc and a new cycle begins. The discharge time of the capacitor Cl dé¬ ends the pulse that activates the means 4 for detecting the emission of the radio signal.

This time is determined by the torque ré¬ resistors RI and R2. Diode D3 is necessary in this embodiment since it is not possible to achieve the desired duty cycle by playing only on the resistors R and R2.

However, this diode introduces a drift in the pulse duration depending on the tempéra¬ ture, which is not tolerable because in one case, when the temperature increases, the pulse is too low ESR du¬ this does not allow the detection means to provide useful information and in the other case, when the temperature decreases, the impul¬ sion is too long, which causes excessive consumption of the device.

In order to compensate for this drift thermochemical nomic, a diode D2 is added in series with the re resistance R2.

Thus, if the resistance of the diode D3 naked dimi¬, the Cl capacitor charges faster. Ce¬ during, diode D2 which has the same caracté¬ teristics as the diode D3, has a resistance which also lowers, c which causes the positively ve input of the operational amplifier has a potential decrease and therefore, causes a faster discharge of the capacitor Cl, which results in that the pulse length remains constant. The output of this operational amplifier activates a transistor of MOS-FET P-channel type B 5592 which acts as the aforementioned switch 7, for periodic activation, i.e. power periodic, for all receiving means and transmission detection of a radio signal by the station traite¬ ment information.

A component type FET filled correcte¬ ment this function because given the low current authorization polA-, the operational amplifier of oscilla¬ tor 6, practically can not provide current.

Note that it is possible to fonc¬ OPERATE oscillator under a lower current, for example 0.1 uA, but the characteristics of the operational am- plificateur make the pulse of the tie sor¬ -ci becomes trapezoidal as shown in Figure 3.

However, there is a wide dispersion on the control voltage of a MOS transistor. This re- sulterait a significant fluctuation of the moment of powering up the rest of the device.

For example, the oscillator 6 described above, which is supplied during the entire life of the portable object, may cause vation Acti pulse of 0.2 s every 2 seconds.

The detection means of the emission of a radio signal are in turn based on the use of a receiving circuit of the type TDA 7021T sold by the RTC company, which provides the presence of a HF wave TF frequency, a sinusoidal signal at the intermediate frequency, or 70 kHz.

For a fixed station emitting a signal to a power of 2 mW, the amplitude of signal Sor- tie of this circuit varies from 1 volt peak to peak at a distance of 1 meter, a few millivolts peak to peak, 10 meters.

The signal provided by this type of component in the presence of an RF wave is shown in Figure 4. As previously explained, the output of this circuit which includes both the receiver means 8, the mixer 12, the oscillator II and the intermediate frequency filter 13, outputs an intermediate frequency signal applied to demodulate freezer 14 and the amplifying means 15 previously described.

These amplification means are in fact constituted by two operational amplifiers with low consumption of TLC Type 272. These operational amplifiers are connected in non-inverting operational amplifiers.

These means are intended to be removed, at high impedance, the intermediate frequency signal of the receiving circuit described above for a- lead to a usable level.

So as to amplify to the maximum the signal supplied by the reception circuit, the positive input of the first operational amplifier is biased at Vcc / 2 through the resistor bridge R7 and R8. The output of this first operational amplifier is at Vcc / 2 because the feedback branch formed by the resistors R15 and R16 is disconnected from ground by capacitor C7. Dynamically, the impedance of this capacitor C7 is very low de- efore the resistor R15 and the gain of this operational amplifier is Gl = 1 + R16 / R15.

The DC component of the signal supplied by the reception circuit described above is fil¬ tree by the input capacitor C3. The filter cutoff frequency formed by the capacitor C3 and the resistor R8 in parallel with resistor R7, must be less than) 70 KHz.

The second operational amplifier is wired by po¬ 0 break for two reasons - firstly, the signal from the first operational amplifier is sufficient to not require a pre-polarization of the input;

- secondly, the output signal of ce¬ he may directly attack the means to detect tion that operate with logic levels.

The DC level to Vcc / 2 of the first operational ampli¬ fier is discontinued by the pas¬ filter up consisting of capacitor C8 and R17 résis¬ tance. The gain of the second operational amplifier is equal to G2 = 1 + R19 / R18.

Upon receipt of a signal provided by the amplification means, the detection means 10 dé¬ writings previously, control the power up other functions, that is to say the other bodies of the device, by via the interrup¬ tor 5a and maintain the supply of the receiving circuit independently of the control of the oscilla¬ tor 6, through the switch 5b. The switch 5a is for example formed by a compo¬ sant Type B 5589 and the switch 5b by a compo¬ sant Type B 5592.

This state is maintained until a reset si¬ gnal be sent for example by the microprocessor CPU of this provi- tif to the detection means.

In fact, the detecting means 10 are constituted by six D flip-flops in CMOS logic as shown in Figure 5 (part of 14174 type).

The clock signal CLK is the signal provided by the second operational amplifier of the amplification means 15. This is the sinusoidal signal provided by the receiving circuit, amplified and whose negative half has been removed.

These means are continuously supplied so that the output of the last flip-flop which controls the MOS transistor forming the power switch 5a from the rest of the organs of the device, has its permanently set level.

When powering means for receiving and amplifying means, said latch reset signal remains at zero so as not to take into account transients due to the establishment of the voltage.

Once stable 1'état assembly and the reset signal back to "1", as a result of the charging of the capacitor C6, each rising edge of the CLK signal advanced a flip-flop "1" ini- tially present to the input of the first flip-flop of these means.

When the "1" arrives at the output of the flip-flop der¬ niere, it turns on with the trans¬ istor MOS, 5a, the rest of the device bodies and maintains power receiving means, by via the MOS transistor, 5b, regardless of the oscillator, so that these can be used for data transfer.

Several scales have been cascaded, because even in the absence of an RF wave, some parasitic thy can be amplified and sent to the detection means.

Once the output of the circuit increased to "1", only a reset signal from, for exam- pie of the microprocessor of the in¬ training processing unit of the portable device can reset the flip-flops and the cut 'food.

It is therefore understandable that the life of the one electric power supply source is deter- mined by the following parameters:

- consumption of the oscillator 6;

- polling period;

- width of the detection window or Ȭ coulement; - capacity of the battery 1; and consumer electronics détec¬ tion. Thus, for a supply voltage of 6 V device, the following parameters are fixed: - consumption of the low oscillator cons¬ ommation 1.5 uA consumption détec¬ tion Electronics: 7 mA

- width of the detection window: 0.2 ms.

To an oscillation period of 1 s and a battery capacity of 150 mAh, an average fuel consumption is obtained;

- 1.5 uA consumption of the low power oscillator;

- 7 x 10-3 x 2 x 10 -4, that is to say 1 4μA of averaged consumer electronic detection portion, an cons¬ ommation 2.9 uA. The autonomy of the assembly is then: 150 / 2.9 x 10-3 x 24 x 365 = 5.9 an¬ born. It goes without saying of course that, for a period of oscillation pé¬ 2 seconds, dividing the constant ommation detection electronics 2.

Supplied at 3 volts, the integrated device in the portable object, see the following parameters take the following values:

0.5 uA for the consumption of the oscillator low consumption tor,

- 4 mA for the consumption of électroni¬ that detection.

Is then obtained for a oscilla¬ tion period of 1 s, for a battery capacity of 150 mAH and a listening window width of 0.2 ms, a total consumption averaged 0.5 x 10 - 4 + 4 x 2 x 10 -3 10 -4 = 1.3 uA and a life of 150 / 1.3 x 10 "1 x 24 x 365 = 13.1 years.

Claims

1) Holding and resignation information by radio-electric means, integrated in a portable object and adapted to exchange information with an information processing station, said device comprising reception means and means for transmission of information connected to a central processing unit of information (2), and a source (1) for supplying electrical energy, characterized in that it further comprises means (3) periodical activation of means (4) for detecting the emission of a radio signal by the sta¬ tion information processing apparatus, whose output is connected to means (5a) for controlling the supply of the rest (2) bodies of this device in response to detection of said signal.
2) Device according to claim 1, ca¬ terized in that the activation means (3) com¬ take an oscillator (6) whose output activates a switch (7) feeding means détec¬ tion (4 ) connected between the electric power supply source (1) and the detection means.
3) Device according to claim 1 or 2, characterized in that the detection means compren- NEET means (8) for receiving the electrical signal radio¬ whose output is connected to the input determining means (9) and with means for détec¬ tion (10) of the intermediate frequency of said signal, to activate the control means (5a). 4) Apparatus according to any preceding vendications into regenerations, characterized in that the control means comprise a switch (5a) for supplying the rest of the members (2) of the device, connected between the power supply source electrical connector (1) and these organs. 5) Apparatus according to any preceding vendications into regenerations, characterized in that the receiving means (8) and determination (9) of the intermediate frequency signal are formed by the information receiving means of the device.
6) Apparatus according to any preceding vendications into regenerations, characterized in that it com¬ carries a switch (5b) self-power detecting means (4), controlled by these means. 7) Apparatus according to any preceding vendications into regenerations, characterized in that the detection means (4) receive a signal réini¬ tialisation the rest of the members (2) of the device.
8) Device according to claims 2, 4 and 6, characterized in that said switches are formed by MOS transistors.
PCT/FR1993/000858 1992-04-02 1993-09-07 Radio transceiver for the reception and transmission of information WO1995007516A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
FR9204013A FR2689707B1 (en) 1992-04-02 1992-04-02 Device for receiving and transmitting information by radio-electric means.
PCT/FR1993/000858 WO1995007516A1 (en) 1992-04-02 1993-09-07 Radio transceiver for the reception and transmission of information

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR9204013A FR2689707B1 (en) 1992-04-02 1992-04-02 Device for receiving and transmitting information by radio-electric means.
PCT/FR1993/000858 WO1995007516A1 (en) 1992-04-02 1993-09-07 Radio transceiver for the reception and transmission of information
AU49659/93A AU4965993A (en) 1992-04-02 1993-09-07 Radio transceiver for the reception and transmission of information

Publications (1)

Publication Number Publication Date
WO1995007516A1 true WO1995007516A1 (en) 1995-03-16

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/FR1993/000858 WO1995007516A1 (en) 1992-04-02 1993-09-07 Radio transceiver for the reception and transmission of information

Country Status (1)

Country Link
WO (1) WO1995007516A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6133947A (en) * 1995-11-15 2000-10-17 Casio Computer Co., Ltd. Image processing system capable of displaying photographed image in combination with relevant map image

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4641374A (en) * 1984-08-08 1987-02-03 Kabushiki Kaisha Toshiba Information medium
EP0296414A2 (en) * 1987-06-12 1988-12-28 Oki Electric Industry Company, Limited IC Card
WO1991013499A1 (en) * 1990-02-23 1991-09-05 Braennstroem Roland A receiver and transmitter arrangement intended preferably for an electronic price information system
EP0533584A1 (en) * 1991-09-20 1993-03-24 Dominique Bernard Hamel Radio wave information receiving and emitting device and information exchange system using such a device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4641374A (en) * 1984-08-08 1987-02-03 Kabushiki Kaisha Toshiba Information medium
EP0296414A2 (en) * 1987-06-12 1988-12-28 Oki Electric Industry Company, Limited IC Card
WO1991013499A1 (en) * 1990-02-23 1991-09-05 Braennstroem Roland A receiver and transmitter arrangement intended preferably for an electronic price information system
EP0533584A1 (en) * 1991-09-20 1993-03-24 Dominique Bernard Hamel Radio wave information receiving and emitting device and information exchange system using such a device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6133947A (en) * 1995-11-15 2000-10-17 Casio Computer Co., Ltd. Image processing system capable of displaying photographed image in combination with relevant map image

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