# US 12,675,189 B2 · Pseudoinverse-based noise equalization > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,675,189 B2 - Document ID: US12675189B2 - Status: Granted - Kind: B2 - Application number: 18/498,425 - Filed: 2023-10-31 - Published: 2024-05-02 - Granted: 2026-07-07 - Earliest claimed: 2022-10-31 - Assignees: Microchip Touch Solutions Limited - Applicants: Microchip Touch Solutions Limited - Inventors: Predrag D. Vukovic - Web page: https://patentgrep.com/patent/US12675189B2 ## CPC - G01R 27/2605: {Measuring capacitance (capacitive sensors G01D5/24)} - G06F 3/0418: {for error correction or compensation, e.g. based on parallax, calibration or alignment} - G01R 35/005: {Calibrating; Standards or reference devices, e.g. voltage or resistance standards, "golden" references (G01R33/0035, G01R35/002 take precedence)} - G06F 3/04182: {Filtering of noise external to the device and not generated by digitiser components} - G06F 3/0446: {using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes} - H04L 25/0244: {with inversion} - H04L 25/03019: {adaptive, i.e. capable of adjustment during data reception} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method including obtaining a first single-ended measurement signal and a second single-ended measurement signal; and producing an equalized measurement signal at least partially based on a predetermined pseudoinverse channel matrix and one or more of: the first single-ended measurement signal and the second single-ended measurement signal. ## Claims ### Claim 1 An apparatus, comprising: a differential measurement circuit to provide a first single-ended measurement signal carried over a first physical channel of the differential measurement circuit and a second single-ended measurement signal carried over a second physical channel of the differential measurement circuit; and an equalization circuit to apply pseudoinverse-based noise equalization to one or more of the first single-ended measurement signal or the second single-ended measurement signal, wherein the pseudoinverse-based noise equalization comprises utilization of a predetermined pseudoinverse channel matrix at least partially based on a Singular Value Decomposition (SVD) of a channel matrix. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the equalization circuit to: produce an equalized measurement signal at least partially based on the predetermined pseudoinverse channel matrix and one or more of: the first single-ended measurement signal or the second single-ended measurement signal. ### Claim 3 (depends on 2) The apparatus of claim 2, wherein coefficients of the predetermined pseudoinverse channel matrix are set to reduce channel effects. ### Claim 4 (depends on 2) The apparatus of claim 2, wherein to produce the equalized measurement signal at least partially based on the predetermined pseudoinverse channel matrix, the equalization circuit to multiply the predetermined pseudoinverse channel matrix with one or more of: the first single-ended measurement signal or the second single-ended measurement signal. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein one or more channels of the differential measurement circuit include physical asymmetries. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the differential measurement circuit includes a differential amplification block to produce an analog single-ended difference signal at least partially based on a difference between the first single-ended measurement signal and the second single-ended measurement signal. ### Claim 7 (depends on 6) The apparatus of claim 6, wherein the differential measurement circuit includes a connection block to receive the first single-ended measurement signal and the second single-ended measurement signal. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein the connection block operable to be coupled with the first physical channel and the second physical channel of the differential measurement circuit. ### Claim 9 (depends on 6) The apparatus of claim 6, wherein the equalization circuit comprises: an analog-to-digital conversion block to produce a digital single-ended difference signal at least partially based on the analog single-ended difference signal; a reconstruction block to produce an uncorrected reconstructed differential signal at least partially based on the digital single-ended difference signal; and a correction block to produce a differential measurement signal at least partially based on the uncorrected reconstructed differential signal. ### Claim 10 An apparatus, comprising: a differential measurement circuit to provide a first single-ended measurement signal and a second single-ended measurement signal; and an equalization circuit to apply pseudoinverse-based noise equalization to one or more of the first single-ended measurement signal or the second single-ended measurement signal, wherein the equalization circuit to produce an equalized measurement signal at least partially based on a predetermined pseudoinverse channel matrix and one or more of: the first single-ended measurement signal or the second single-ended measurement signal, and wherein the equalization circuit comprises: a differential signal reconstructor to produce a preliminary differential measurement signal at least partially based on a single-ended measurement input signal, the single-ended measurement input signal at least partially based on a difference between the first single-ended measurement signal and the second single-ended measurement signal; and a noise equalizer to produce a differential measurement signal at least partially based on the preliminary differential measurement signal and a predetermined pseudoinverse channel matrix. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the equalization circuit comprises: an artifact filter to reduce artifacts in the differential measurement signal produced by the noise equalizer. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the equalization circuit comprises: a target signal amplifier to amplify a target signal in a filtered differential measurement signal produced by the artifact filter to produce an amplified differential measurement signal. ### Claim 13 An apparatus, comprising: a differential measurement circuit to provide a first single-ended measurement signal and a second single-ended measurement signal; and an equalization circuit to apply pseudoinverse-based noise equalization to one or more of the first single-ended measurement signal or the second single-ended measurement signal, wherein the equalization circuit to produce an equalized measurement signal at least partially based on a predetermined pseudoinverse channel matrix and one or more of: the first single-ended measurement signal or the second single-ended measurement signal, and wherein the equalization circuit comprises: a first noise equalizer to produce an equalized first single-ended measurement signal at least partially based on the first single-ended measurement signal; a second noise equalizer to produce an equalized second single-ended measurement signal at least partially based on the second single-ended measurement signal; and a differential driver to produce a differential measurement signal at least partially based on the equalized first single-ended measurement signal and the equalized second single-ended measurement signal. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the first noise equalizer to produce the equalized first single-ended measurement signal at least partially based on a first predetermined pseudoinverse channel matrix, and the second noise equalizer to produce the equalized second single-ended measurement signal at least partially based on a second predetermined pseudoinverse channel matrix. ### Claim 15 A method, comprising: obtaining a first single-ended measurement signal and a second single-ended measurement signal carried a first physical channel of a differential measurement circuit and a second physical channel of the differential measurement circuit, respectively; and producing an equalized measurement signal at least partially based on a predetermined pseudoinverse channel matrix and one or more of: the first single-ended measurement signal and the second single-ended measurement signal, the predetermined pseudoinverse channel matrix at least partially based on a Singular Value Decomposition (SVD) of a channel matrix. ### Claim 16 (depends on 15) The method of claim 15, wherein coefficients of the predetermined pseudoinverse channel matrix are set to reduce channel effects. ### Claim 17 (depends on 15) The method of claim 15, comprising: producing a single-ended measurement input signal at least partially based on a relationship between the first single-ended measurement signal and the second single-ended measurement signal; and producing the equalized measurement signal at least partially based on the predetermined pseudoinverse channel matrix and the single-ended measurement input signal. ### Claim 18 A method, comprising: obtaining a first single-ended measurement signal and a second single-ended measurement signal; and producing an equalized measurement signal at least partially based on a predetermined pseudoinverse channel matrix and one or more of: the first single-ended measurement signal and the second single-ended measurement signal, wherein producing the equalized measurement signal comprises: producing a first single-ended equalized measurement signal at least partially based on the first single-ended measurement signal and a first predetermined pseudoinverse channel matrix of the predetermined pseudoinverse channel matrix; producing a second single-ended equalized measurement signal at least partially based on the second single-ended measurement signal and a second predetermined pseudoinverse channel matrix of the predetermined pseudoinverse channel matrix; and producing a differential measurement signal at least partially based on the first single-ended equalized measurement signal and the second single-ended equalized measurement signal. ### Claim 19 (depends on 18) The method of claim 18, wherein producing a first single-ended equalized measurement signal comprises multiplying the first single-ended measurement signal with the first predetermined pseudoinverse channel matrix. ### Claim 20 (depends on 18) The method of claim 18, wherein producing a second single-ended equalized measurement signal comprises multiplying the second single-ended measurement signal with the second predetermined pseudoinverse channel matrix.