Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Drawings
The drawings are objected to because the unlabeled rectangular box(es) shown in figures 5, 9 and 10 should be provided with descriptive text labels. Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Claim Interpretation
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph:
An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked.
As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph:
(A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function;
(B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and
(C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function.
Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function.
Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function.
Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action.
This application includes one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier. Such claim limitation(s) is/are: “trans-impedance amplifier bandwidth selector” in claims 2 and 12.
Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof. According to [0081], the bandwidth selector is a selectable compensation capacitor or input transistor adjusted to change bias current.
If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1, 10-11, 20, 22 and associated dependent claims are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claims 1, 11, “from a first connection … and from a second connection …” – it is unclear whether the measurement is taken between two nodes. Examiner suggests clarifying with “configured to acquire the transmit voltage measurement between the first connection and the second connection” and “configured to acquire the receive voltage measurement between the third connection and the fourth connection” provided there is proper support.
Regarding claims 10, 20, 22, “the digital processing unit is configured to determine the impedance based on Equation 1” – “Equation 1” should be clearly defined [e.g., Z=R*VT/VR] so the claim can stand individually.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1-2, 4-12, 14-23 is/are rejected under 35 U.S.C. 103 as being unpatentable over “Ganesan”, US Publication 20210330212 in view of “Cheon”, “An Impedance Readout IC with Ratio-Based Measurement Techniques for Electrical Impedance Spectroscopy”.
Regarding claim 1, Ganesan discloses a measurement system comprising:
a signal generator configured to provide a transmit voltage [0028: signal generator 116 generating a signal having a peak voltage VPEAK];
a transmit electrode connected to the signal generator [0026: electrode 104 connected to pin CE0 and the signal generator];
a trans-impedance amplifier having a trans-impedance amplifier input and a trans-impedance amplifier output [0030: transimpedance amplifier (TIA) 128 to convert a current at an input terminal to a voltage output];
a receive electrode connected to the trans-impedance amplifier input [0030: electrode 110 on the F- branch coupled to the input of the current measurement circuitry 126/TIA 128];
voltage measurement circuitry [0029: voltage measurement circuitry 118]; and
a digital processing unit configured to determine an impedance based on the transmit electrode and the receive electrode being in direct contact with a body [0031: circuitry/processors to derive the impedance value of the unknown bio-impedance 102 based on the measured voltage and current].
However, Ganesan does not explicitly disclose: voltage measurement circuitry configured to acquire a transmit voltage measurement from a first connection connected between the signal generator and the transmit electrode and from a second connection connected to the trans-impedance amplifier input, and configured to acquire a receive voltage measurement from a third connection connected to the trans-impedance amplifier input and from a fourth connection connected to the trans-impedance amplifier output; and the impedance based on a ratio of the transmit voltage measurement and the receive voltage measurement – Ganesan derives impedance from measured voltage and measured current [0031]; Ganesan does not explicitly describe the impedance as a ratio of a transmit voltage measurement (voltage across the body between force electrodes) and a receive voltage measurement (voltage across the TIA, between TIA input and TIA output).
Cheon discloses an analogous impedance measurement system with a voltage measurement circuitry configured to acquire a voltage measurement across a target impedance and a voltage measurement across a reference element [resistor] in the current path to determine the target impedance based on a ratio of the measurements to cancel out system nonidealities.
Specifically, Cheon discloses that in an impedance measurement structure with a reference resistor [RREF] connected in series with the target impedance [Figure 2b], the same current flows through both elements, generating two voltage outputs: vm(t) across the target impedance and vr(t) across the reference resistor [Section 2, Equation (1): “vm(t) = |Zm|Ain cos(2πfint + θVCCS + θm)” and “vr(t) = RREF Ain cos(2πfint + θVCCS)”; Figure 5a showing measurement paths that process both vm(t) and vr(t)]. Cheon teaches that these voltages are acquired by readout circuitry for impedance determination. Cheon also explicitly discloses determining impedance as a ratio of the voltage measurement across the target and the voltage measurement across the reference element: “MAG(Zm) = Vmag/Vmag,r × RREF” [Equation 7, Section 2.1]. Cheon further teaches that this ratio-based approach cancels errors: “the magnitude measurement accuracy is only affected by the mismatch between the two Mag-paths instead of the nonlinearity and phase delays of the circuit components such as the VCCS, IAs, and comparators” [Section 2.1, discussion following Equation 8]. As such, Cheon’s reference resistor (RREF) in the current path is functionally analogous to the TIA feedback resistor recited in the claims: both are reference elements positioned such that the current of interest flows through them, producing a voltage proportional to that current. In the claimed system, the “receive voltage measurement” [between TIA input and TIA output] corresponds to the voltage across the TIA feedback resistor, which is proportional to current -- precisely as Cheon’s vr(t) = RREF × I is proportional to current.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Ganesan’s system to acquire a transmit voltage measurement between the signal generator/transmit electrode node and the TIA input [measuring voltage across the body between the force electrodes] and acquire a receive voltage measurement between the TIA input and TIA output [measuring voltage across the TIA feedback element proportional to current], and to determine impedance as the ratio of these two voltage measurements, as taught by Cheon’s ratio-based measurement technique. Ganesan and Cheon are combinable because they both address the common problem of accurately determining the impedance of biological/target materials while compensating for measurement errors. This modification would enhance Ganesan’s system by: simplifying the measurement architecture by eliminating the need for separate sense electrodes [e.g., S+ and S−] and the associated amplifier, thereby reducing electrode count and system complexity; improving measurement accuracy through ratio-based detection, which Cheon demonstrates cancels errors from signal generator nonlinearity and amplifier gain-bandwidth variations [Section 2.1, Equation 8; Abstract: “accuracy is enhanced by 30%”]; and leveraging the TIA feedback resistor implicitly present in Ganesan’s system as the reference element for ratio-based detection, since the TIA output provides a voltage proportional to current flowing through the body.
Regarding claim 2, Ganesan does not explicitly detail a bandwidth selector for its trans-impedance amplifier. However, Cheon discloses an impedance measurement amplifier circuit comprising reconfigurable capacitor banks that act as a bandwidth selector [Section 3.1, “By changing these capacitor values, the IA gain can be configured… The bandwidth of the IA is 225 kHz at the maximum gain mode… In the minimum gain mode, it has a bandwidth of 3.6 MHz”]. It would have been obvious to an ordinary artisan to incorporate the reconfigurable bandwidth selection teachings of Cheon into the amplifier circuitry of Ganesan to allow the system to dynamically adjust its bandwidth to accommodate different measurement frequency ranges, thereby optimizing the signal-to-noise ratio [i.e., matching the TIA bandwidth to the measurement frequency reduces noise] for various bio-impedance measurement conditions.
Regarding claim 4, Ganesan explicitly discloses that the signal generator is a sinusoidal signal generator [0028: “Circuitry 150 can include a signal generator 116 (e.g., sinusoidal signal generator)”]. Furthermore, Cheon discloses that the sinusoidal signal generator operates over a finite bandwidth, specifically generating signals with variable frequencies over a defined range [Abstract “wide frequency range of 10 Hz to 1 MHz”; Section 1, “creates a sinusoidal voltage waveform with variable frequencies”].
Regarding claim 5, Cheon discloses placing a reference resistor in series between the signal generator and the target impedance [the body] to compensate for errors, where the voltage measurement is taken from the connection between this resistor and the target [Section 1, Figure 2b showing the reference resistor connected in series with the target impedance; Section 2, “The sinusoidal input current signal… flows through the target impedance (Zm) and reference resistor (RREF)”]. It would have been obvious to an ordinary artisan to incorporate the series reference/limiting resistor of Cheon into the transmission path of Ganesan to provide a known reference voltage drop for the ratio-based impedance calculation, thereby improving measurement accuracy and protecting the body from excessive current.
Regarding claim 6, Ganesan discloses a system with multiple electrodes, including electrode 106 (S+ branch), electrode 108 (S− branch), and electrode 110 (F− branch) on the receive side of the bio-impedance [0024–0027]. Ganesan discloses that the S+ branch electrode 106, S− branch electrode 108, and F− branch electrode 110 are all positioned on the body to sense signals resulting from the current flow through the bio-impedance. It is well-known that multiple receive electrodes can be employed for different measurement configurations, multi-channel measurements, or redundancy. In the combination of Ganesan and Cheon applied to the claimed two-electrode approach, it would have been obvious to an ordinary artisan that providing multiple receive electrodes [e.g., at different body locations] enables multi-site impedance measurements or electrode selection for optimal signal quality.
Regarding claim 7, Ganesan discloses that the circuitry and processors are configured to derive the impedance value of the unknown bio-impedance of the body [0031: “The circuitry 150 can include circuitry and/or one or more processors (not shown) to derive the impedance value of the unknown bio-impedance 102”; 0022: “The bio-impedance may be produced by a body, or portion thereof, of a subject”].
Regarding claim 8, while Ganesan does not use the exact phrase “analog to digital converter” in the primary embodiment description, it explicitly discloses that the voltage and current measurement circuitry include a “Discrete Fourier Transform (DFT) block” [0029+: DFT block 122 and DFT block 130]. It is a well-known, implicit scientific principle that performing a Discrete Fourier Transform on an analog voltage signal requires first converting that analog signal into the digital domain using an analog-to-digital converter (ADC). Furthermore, Cheon explicitly discloses the use of an analog-to-digital converter in the context of processing these exact types of phase and voltage measurements in a polar demodulator structure [Section 1: “it is necessary to use a high-resolution analog-to-digital converter”].
Regarding claim 9, Ganesan discloses a trans-impedance amplifier (TIA 128) used to convert a current at its input to a voltage at its output [0030]. Examiner takes Official Notice that a standard trans-impedance amplifier circuit utilizes a feedback resistor connected between the inverting input and the output to perform current-to-voltage conversion, as this is a fundamental defining component of a TIA that sets the transimpedance gain (V_out = -I_in × R_feedback). An ordinary artisan would implicitly understand that the TIA 128 of Ganesan includes this standard feedback resistor to function as described.
Regarding claim 10, Cheon teaches calculating impedance based on the ratio of the measured voltages multiplied by the reference resistance [Equation 7].
Regarding claim 11, he combination of Ganesan and Cheon discloses providing and connecting the components as described in the analysis of claim 1. It would have been obvious to an ordinary artisan to manufacture the system by physically connecting the disclosed components.
Similarly, regarding claims 12, 14, 15, 16, 17, 18, 19, and 20, which include the steps of providing/connecting the specific components recited in apparatus claims 2-10 (e.g., connecting a bandwidth selector, connecting a multiplexer, providing a finite bandwidth source, connecting a limiting resistor, connecting multiple receive electrodes, configuring for bio-impedance, providing an ADC, connecting a TIA resistor, and configuring for Equation 1) – as established in the rejections of claims 2-10, the combination of Ganesan and Cheon discloses the structural and functional equivalents of these limitations. It would have been obvious to one of ordinary skill in the art to manufacture the measurement system by physically connecting and configuring these known components to yield the predictable system described above.
Regarding claim 21, the combination of Ganesan and Cheon discloses the method steps, as Ganesan teaches applying the AC voltage and acquiring measurements, and Cheon teaches calculating the impedance based on the ratio of the target measurement and the reference measurement (which corresponds to the voltage across the TIA feedback resistor) as set forth for claim 1.
Regarding claim 22, Cheon teaches the ratio equation [Equation 7] as discussed for claim 10.
Regarding claim 23, Cheon teaches changing the bandwidth of the measurement amplifier between different modes [e.g., 225 kHz and 3.6 MHz] using reconfigurable capacitor banks [Section 3.1]. It would have been obvious to an ordinary artisan to operate the combined system of Ganesan and Cheon by taking measurements at different bandwidths to ensure accurate impedance readings across a wide sweep of frequencies to capture different tissue characteristics.
Claim(s) 3 and 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ganesan and Cheon as applied to associated claims above, and further in view of “Ano”, US Patent 11047821.
Ganesan in view of Cheon does not explicitly detail a multiplexer for switching these specific connections. However, Ano discloses a bio-impedance measurement system comprising a multiplexer [mux 112] that can be controlled to connect signal paths of different pins to different parts of the circuitry to acquire different measurements [col.3, ll.1-11]. It would have been obvious to combine Ano with Ganesan/Cheon to allow a single measurement circuit to dynamically switch between the transmit voltage measurement and the receive voltage measurement, reducing hardware duplication and saving chip area.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Tse Chen whose telephone number is (571)272-3672. The examiner can normally be reached M-F 7-3 EST.
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/TSE CHEN/ Supervisory Patent Examiner, Art Unit 3791
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