MXPA00001964A - Metering circuit - Google Patents

Abstract

A current detector and metering circuit is provided for a dielectrokinesis detecting device. This device is particularly useful in the areas of locating obscured entities, such as human beings, animals, materials, or controlled substances. A current detector is attached to an antenna and detects when subtle changes in the dielectrokinesis occurs within an detection environment. The present current detector automatically zeros itself to ambient electric field values and then has a heigtened sensitivity for changes in that electrical field caused by changes in the dielectrokinesis. The present invention can be used for detection of hidden entities or substance, for motion detection, for medical diagnostic detection, and other uses.

Description

MEASUREMENT CIRCUIT FIELD OF THE INVENTION The present invention relates to methods and an apparatus for locating several entities, by detecting the dielectrokinesis response in the entity. In particular, the present invention relates to a method and apparatus for detecting and measuring the current indicators of the dielectrokinesis response.

BACKGROUND OF THE INVENTION Human beings, animals, organic objects and other entities generate an external electric field and gradients thereof, which cause phenomena of polarization, depolarization and repolarization in cell membranes.

This phenomenon results in polarization states that can be detected by a detector device, as described in the North American Patent Applications.

Nos. 08 / 758,248 and 08 / 840,649, appended hereto as Appendices A and B. The background information regarding the effects of dielectrokinesis and how they can be detected is fully discussed in those applications appended hereto and incorporated therein as a reference and therefore, for reasons of brevity, that discussion is not repeated here. The present invention relates to an improvement made to the detector and to the measurement circuits associated with the inventions described in those applications. In particular, the circuitry shown, for example in Figure 5 of the North American Application No. 08 / 758,248 (Appendix A) includes an antenna 102 in which the forces associated with the effects of dielectrokinesis act. The antenna 102 is connected to a low-pass filter Fl, which sends its output to a current detection device (in Figure 5 shown as JFETs, J1, J2 and J3). After the current detection JFETs, the current continues to a current meter, MI, and to an optional piezoelectric buzzer Pl. The current detectors (JFETs Jl, J2 and J3), together with the Ml meter and the piezoelectric buzzer Pl are used to detect dim currents in the antenna 102 that are induced by the effects of dielectrokinesis. Thus, according to the description of Figure 5 of application 08 / 758,248, the operator uses an antenna to detect the effects of dielectrokinesis associated with the presence of an entity to be detected and therefore creates a current very low level in association with that detection. The low level current detector in Figure 5 takes the low level current induced in the antenna 102 and passes it through a low pass filter Fl and then into the gate of the respective JFETs. If the current exceeds the threshold operation value of the gate, for the respective JFETs, the JFETs are opened to complete with this a circuit powered by the battery Bl and including the meter Ml and the piezoelectric buzzer Pl. In this form, the current induced in the antenna 102 will control the operation of the meters Ml and the piezoelectric buzzer Pl to thereby detect the effects of dielectrokinesis in the vicinity of the antenna 102 and display them (by means of the meter Ml and the piezoelectric buzzer Pl). ) to the operator. The present invention is a circuit that is specifically designed to improve the detection of low level currents that are induced in the antenna by the effects of dielectrokinesis of an unknown entity that exists in the vicinity of the antenna. In particular, it is desirable to improve the distance at which the detecting device can be used accurately to detect the unknown entity. That is, in the detectors, it is desirable to increase the distance at which the detector device can unequivocally identify the presence of the entity. Unfortunately, as the distance between the detector and the entity to be detected increases, the intensity of the signal received by the detector, due to the effects of dielectrokinesis of the unknown entity, it is dramatically reduced and can, therefore, result in mistaken identifications of the presence of the entity. Since the current levels induced in the antenna 102 may already be relatively low (of the value or below, the entry threshold to the gate of the JFETs), the reductions in the current levels (and hence the signal ratio to noise) can have a dramatic impact on performance characteristics, including the maximum effective detection distance. In addition, the detector described with respect to Appendix A and B includes circuit assemblies that are designed to detect the electric field in the vicinity of the detector, caused by the effects of dielectrokinesis induced by the presence of the unknown entity. The detection occurs as a result of the induced current in the antenna 102 that exceeds the gate entry threshold in JFETs Jl, J2 and J3. Current levels below the threshold will fail at detection. This method can provide low operating sensitivity since the operator will receive either a positive indication (through the movement of the meter and the piezoelectric buzzer) of whether the current threshold is exceeded, or will not receive any indication if it is not.

SUMMARY OF AN EXEMPLARY MODALITY OF THE INVENTION The measurement circuit, hereby, operates in conjunction with the antenna, and with the filtering and detection circuit described in Appendix A and B. By replacing the JFETs of Figure 5 of Appendix A with the circuit herein, the Operator can detect more tenuous indications of the presence of an unknown entity. With the measurement circuit of the present, the operator adjusts the level of detection to a particular value (preferably a null value), so that changes in dielectrokinetic effects are detected with greater sensitivity. In this way, for example, if the environmental levels of the electric field are 20 microvolts per centimeter and the change in the field, caused by the effect of dielectrokinesis of introducing an unknown entity into the effective range of the antenna 102 causes a change of +1 microvolt per centimeter in ambient conditions, the change from 20 to 21 in a meter could not be distinguished in the gates of the JFET. In that case, the meter and the piezoelectric buzzer would not properly distinguish between an environmental condition and an altered condition. However, if the current detection circuit is "zeroed" in the ambient condition, the change from zero (environmental condition) to +1 microvolt per centimeter (when the unknown entity is introduced to the effective range of antenna 102) it can be identified more sensitively by the detection circuit and therefore provides the operator with a more obvious identification of the presence of an unknown entity. The present invention thus advantageously provides improved sensitivity for detecting the presence of unidentified entities and also provides effective operation at increased distances.

BRIEF DESCRIPTION OF THE DRAWINGS Other advantages and objects of the present invention will be described in detail with reference to the accompanying drawings, in which: Figure 1 is a circuit diagram of an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES HEREIN Figure 5 of Appendix A shows a circuit diagram in which an antenna 102 detects an electric field in the vicinity of the detector and supplies a low value current to a current sensing circuit. The present invention can be substituted in the apparatus described in Appendix A with respect to the same antenna 102 by replacing the circuit of Figure 1 (appended) by the current detection circuit of Figure 5 of Appendix A. In this respect , Figure 1 of the present invention illustrates an exemplary embodiment of the improved current sensing circuit. As shown in Figure 1, circuit 10 is connected to antenna 2 (which coincides with antenna 102 of Figure 5 of Appendix A). The antenna 2 provides a low level current when the electric fields are brought to the effective proximity thereof. The current sensing circuit 10 detects the current provided by the antenna 2 and provides an indication of that current to the operator, through the meter 50, in accordance with the purposes described with respect to the North American Application No. 08 / 758,248. Current detector 10 includes a series of amplifiers, starting with a first operational amplifier 12 connected to a series of amplifier circuits 30, 32, 34, and 36. Operational amplifier 12 is preferably a low-precision operational amplifier. noise and low frequency which allows very low level input currents (from the picoampere level). An exemplary operational amplifier suitable for the current detector of the present is marketed by Analog Devices of Norwood, Massachusetts, under the product number AD645. Alternative amplifiers can be used as long as they have a voltage spectral density curve to operate at a frequency at which the dielectrokinetic effects can be detected with sufficient sensitivity. For example, for the detection of human beings through the detection of the dielectrokinetic effects of the electrical signals present in a human heart, an amplifier with a voltage spectral density curve operating at approximately 18 Hz or less will be sufficient, and preferably at about 10 Hz. Other and different operational characteristics may be more appropriate for the detection of other types of entities or for the detection of alternative physiological characteristics of human entities. The frequency of operation to detect a human depends on the pulse rate of the heart. Typically, the pulse frequency is about 1 to 2 Hz. By transforming the pulse signal, by means of Fourier transformation, a fundamental frequency is found at approximately 17.5 Hz (hence the ideal operational characteristic of 18 HZ or less). Of course, higher frequencies can be employed by focusing on the components of the higher end of the Fourier signal up to a frequency level for which the signal-to-noise ratio remains low enough to extrapolate a useful signal. The inventors have discovered that with the present technology those Fourier and higher components can be used up to about 50 Hz in Europe and 60 Hz in the United States, before the background noise exceeds the Fourier component signals. The inverting input of the operational amplifier 12 receives a feedback signal from the output of the operational amplifier 12. The non-inverting input of the operational amplifier 12 receives the signal from the antenna through a series capacitor Cl. Cl can be selected based on the specific design constraints of the system used, but may preferably be a metal film capacitor, for example 0.47 μF. The output of the operational amplifier 12 is then fed to the inverting input of the amplifier 14 within the first amplifier stage 30 and through the resistor R5. Each of the amplifier stages 30, 32, 34, and 36 includes a resistor (R5, R6, R7, and R8 + R9) at the inverting input. In addition, the output of each of the amplifiers 14, 16, 18 and 20, of each of the respective amplifier stages 30, 32, 34 and 36, is fed back to the inverting input of the respective amplifier through a combination in parallel of the corresponding resistors and capacitors R1, R2, R3, R4, and C2, C3, C4, and C5. Also, at the output of the amplifier 14 is the coupling capacitor C6 which can be a 2.2 μF ceramic capacitor connected in series between the amplifier 14 and the second amplifier stage 32. The non-inverting inputs of the amplifiers 14 and 16 are connected to ground through resistors Rll and R12. For the non-inverting inputs of the amplifiers 18 and 20 of the amplifier stages 34 and 36, respectively, the automatic reset settings are provided. In particular, in the third amplifier stage 34, the non-inverting input of the amplifier 18 is connected to a variable resistor R14 which is connected in series to a positive voltage (for example, +9 volts) through the resistor R13 and is connected at a negative voltage (for example, -9 volts) through resistor R15. The variable resistor R14 forms a part of the zero deviation adjustment circuit 22, which is connected to the non-inverting input of the amplifier 18. The zero deviation adjustment circuit 22 is provided to allow the operator to adjust the gain of the third stage and accommodate the level variation that may exist in the high gain amplifier stages. As an exemplary embodiment of the zero adjustment circuit 22, the resistor R3 can have a value of 100 Kilohm, the resistor R15 can have a value of 100 Kilohm and the resistor R14 can have a value of 5 Kilohm. In addition, capacitor C9 can have a value of 0.1 μF and can be a metal film capacitor. The fourth amplifier stage 36 includes the amplifier 20 and the input resistors R8 in series with R9. The resistor R8 is variable and can have a value of 250 Kilohm, while the resistor R9 is fixed at a value of 220 Kilohms. Resistor R8 is a potentiometer that provides the operator with a sensitivity adjustment. In addition, the adjustment circuit 24 is provided which is provided at the non-inverting input of the amplifier 20 to provide an adjustment to the center for the meter to be used. This allows the operator to determine if the presence of an unknown entity causes the measuring circuit to form capacitance or extract capacitance. The center adjustment circuit 24 includes a variable resistor R16 connected between the positive and negative voltage. It can be a 50 Kilohm resistor connected in parallel with the CIO capacitor which can be a metal film capacitor of 0.1 microfarad. Ideally, R16 is adjusted for half scale (ie centered on the meter) when no input signal is present. The output of the fourth amplifier stage 36 is provided to a RIO resistor which may be 47 Kilohmms but will be adjusted depending on the meter used. The output of the RIO resistor is provided to the meter 50 which will identify to the operator the presence of current in the antenna 2, amplified by the different amplifier stages discussed previously. Working, a very small current is detected in antenna 2 whenever dielectrokinetic effects cause a change in the electric field, compared to environmental conditions. This current can be of the order of picoamps and is provided, through the blocking capacitor Cl, to the non-inverting input of the amplifier 12. This amplifier is frequency limited to 10 Hz which is a preferred frequency, at which the tests show that the tenuous effects of dielectrokinesis are observed, due to the presence of an unidentified entity and the coupling between the unidentified entity and the detector is maximized. The amplifier 12 increases the signal strength and provides the output to the four amplifying stages 30, 32, 34 and 36. These amplifier stages further reinforce the value of the signal, such that the meter 50 at the output of the detector circuit Current 10 can identify with a high degree of clarity, the presence of an unidentified entity, even at greater distances, such as, for example, 20 meters or more. The circuit 10 will float in the ambient electric field conditions, such that after, for example two or three seconds, the circuit is canceled to the environmental condition. Then, changes in the electric field caused by the dielectrokinetic effects of introducing another entity in the vicinity of antenna 2 will be recorded by the measurement circuit. In this way any change to the environmental condition can be detected with greater sensitivity, directly in the meter that is used, as discussed above. The present invention is not limited to the precise circuit shown in Figure 1, but may employ other circuit designs that are low pass and manipulated, of a device having a voltage spectral density curve, so that it operates at about 50 Hz or less, and preferably about 10 to 18 Hz. This allows the circuit 10 to detect a load on the antenna 2 and use the load to apply a series of gains for detection by a meter or other suitable device. The present invention has many uses and is not necessarily limited to a particular use. The inventors have found that the antenna detector and the measurement circuit can be used to detect the presence of hidden entities, including humans, animals, polymers, controlled substances, etc. Additional applications include motion detection (motion detectors) in a defined environment. For example, when an entity is completely quiet within a room, the circuit of the present will first detect the entity, then (after a few seconds) it cancels the environmental condition. Subsequently, if the entity moves, the meter will record the changes in the dielectrokinetic effect in the room, caused by the change in the physical orientation of the human heart, in relation to the detection antenna 2 (which in turn changes the electric field detected by antenna 2). Another application of the invention is within the field of medical diagnosis. In particular, the invention can be used to numerically characterize the electric field associated with a human cardiac muscle and the conducting nerves. This allows the operator to observe these characteristics of the electric field against a pattern, in order to provide an indication of the health of the heart. A possible characteristic (among many different potential characteristics) that can be detected is the variability of the heart rate and the synchronization between the sympathetic and parasympathetic rhythms. In this regard, the present invention is more sensitive to detect heart condition than, for example, the ECG tests of the prior art. An alternative, additional use of the invention is operation in an autonomous mode, without the presence of a "reference entity" (such as a human operator) that is in contact with the ground plane GP1., as shown in Figure 5 of Appendix A and as described on page 12 of Appendix A. The inventors have found that, by selecting the proper operating characteristics, of the amplifier 12 (as described above), the Detection and measurement will work without a reference entity that is in physical connection with the ground plane. This allows the device to function as an independent device, without the need for an operator who is physically present. Although the invention has been described in relation to what is considered, in the present, the most practical and preferred modalities, it should be understood that the invention will not be limited to the described modalities, but on the contrary, it is intended to cover several modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims (25)

NOVELTY OF THE INVENTION Having described the above invention, it is considered as a novelty, and therefore, the content of the following is claimed as property: CLAIMS

1. An apparatus for detecting a change in the effects of dielectrokinesis in an environment characterized, at any instant, by an instantaneous, environmental dielectrokinetic condition, characterized in that it comprises: a current detector for the electrical connection to an antenna and for receiving from the antenna a antenna signal indicating the change in the effects of dielectrokinesis, comprising: a low input current amplifier, having a voltage spectral density curve to operate at 50 Hz or less and connected to receive the signal from the antenna and to output a first signal and, an amplifier stage connected in series with the low input current amplifier, to amplify the first signal in an output signal for the use of a detection device and to identify the change in the effects of dielectrokinesis, where the amplifying stage includes a reset circuit to periodically standardize e the output signal up to a predetermined value, equal to the dielectrokinetic, environmental, instantaneous condition.

2. An apparatus according to claim 1, characterized in that the signal of the antenna is low frequency and low current in the low input current amplifier.

An apparatus according to claim 1, characterized in that the low current amplifier is an operational amplifier having a voltage spectral density curve operating below 18 Hz.

4. An apparatus according to claim 1. 1, characterized in that the low input current amplifier is limited to 10 Hz or less.

5. An apparatus according to claim 1, characterized in that the low input current amplifier is an operational feedback amplifier.

6. An apparatus according to claim 1, characterized in that the amplifier stage includes a series of amplifiers.

An apparatus according to claim 6, characterized in that the series of amplifiers includes, from a first to a third amplifier stage, the first amplifier stage is a fixed gain amplifier, the second amplifier stage is a variable gain amplifier that varies according to an adjustment of zero deviation, and, the third amplifying stage is a variable gain amplifier that varies according to an adjustment to the center.

8. An apparatus according to claim 7, characterized in that the second amplifying stage includes a voltage divider circuit to provide zero deviation adjustment.

9. An apparatus according to claim 7, characterized in that the third amplifying stage includes a voltage divider circuit, to provide adjustment to the center.

10. An apparatus according to claim 7, characterized in that it also includes a potentiometer between the second and third amplifier stages.

11. An apparatus according to claim 7, characterized in that the first to the third amplifier stages are connected in series consecutively.

12. An apparatus according to claim 7, characterized in that it also includes a fourth amplifying stage.

13. An apparatus according to claim 1, characterized in that the resetting circuit periodically standardizes the output signal to a null value.

14. A method for detecting a change in the effects of dielectrokinesis in an environment characterized, at any instant, by an environmental, instantaneous dielectrokinetic condition, the method is characterized in that it comprises the steps of: receiving, from an antenna, an antenna signal indicative of the change in the effects of dielectrocinecis, first amplify the signal of the antenna by means of a low input current amplifier, having a voltage spectral density curve, so that it operates below 50 Hz and output the resulting signal as a first signal, and , secondly amplify the first signal in an output signal, to be used by a detection device and identify the change in the effects of dielectrokinesis, including the step of: periodically standardizing the output signal to a predetermined value of equal measure that the environmental, instantaneous dielectrokinetic condition.

15. A method according to claim 13, characterized in that the first amplification step includes the amplification step at low frequency.

16. A method according to claim 13, characterized in that the first amplification step includes the amplification step using an operational amplifier having a voltage spectral density curve operating below 18 Hz.

17. A compliance method with claim 13, characterized in that the first amplification step includes the amplification step using an amplifier limited to 10 Hz or less.

18. A method according to claim 13, characterized in that the step of first amplification includes the step of feedback of the first signal.

19. A method according to claim 13, characterized in that the step of second amplification includes the step of amplification through a series of amplifiers.

20. A method according to claim 19, characterized in that the step of second amplification includes the amplification steps through a first to a third amplifier stage, and wherein: the first amplifier stage provides a fixed gain, the second stage The amplifier provides a variable gain, which varies according to an adjustment of zero deviation, and, the third amplifier stage provides a variable gain that varies according to an adjustment to the center.

21. A method according to claim 20, characterized in that the second amplifying stage provides a voltage divider circuit to provide the zero deviation setting.

22. A method according to claim 20, characterized in that the third amplifying stage provides a voltage divider circuit to provide adjustment to the center.

23. A method according to claim 20, characterized in that it also includes the step of adjusting a potentiometer between the second and third amplifier stages.

24. A method according to claim 20, characterized in that the step of second amplification includes the step of amplification through a fourth amplifier stage.

25. A method according to claim 13, characterized in that the step of periodic standardization includes the standardization of the output signal to a null value.