# US 9,438,463 B2 · System for the correction of amplitude and phase errors of in-quadrature signals, corresponding receiver and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,438,463 B2 - Document ID: US9438463B2 - Status: Granted - Kind: B2 - Application number: 14/751,339 - Filed: 2015-06-26 - Published: 2016-03-31 - Granted: 2016-09-06 - Earliest claimed: 2014-09-25 - Assignees: STMicroelectronics S.r.l. - Applicants: Stmicroelectronics S.R.L. - Inventors: Leandro Grasso; Ranieri Guerra; Giuseppe Palmisano - Web page: https://patentgrep.com/patent/US9438463B2 ## CPC - H04L 27/3836: {in which the carrier is recovered using the received modulated signal or the received IF signal, e.g. by detecting a pilot or by frequency multiplication} - G06F 17/10: Complex mathematical operations {(function generation by table look-up G06F1/03; evaluation of elementary functions by calculation G06F7/544)} - H03D 3/009: {Compensating quadrature phase or amplitude imbalances} - H04L 27/0014: {Carrier regulation (of chaotic carriers H04L27/001; for multicarrier receivers H04L27/2657)} - H04L 27/3863: {Compensation for quadrature error in the received signal} - H04L 2027/003: {at baseband only} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H03D: DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER (masers, lasers H01S; circuits capable of acting both as modulator and demodulator H03C; details applicable to both modulators and frequency-changers H03C; demodulating pulses H03K9/00; transforming types of pulse modulation H03K11/00; coding, decoding or code conversion, in general H03M; repeater stations H04B7/14; demodulators adapted for AC systems of digital information transmission H04L27/00; synchronous demodulators adapted for colour television H04N9/66) ## Abstract A system may be for the correction of phase and amplitude errors. The system may receive a first input signal and a second input signal and supply a first output signal and a second output signal. The system may include two adders that supply the first and second output signals, respectively. The two adders may be configured for computing a sum of the first and second input signals, and multiplying the weighted sum by a third coefficient. Moreover, the first coefficient or the second coefficient of the first adder may be variable to enable correction of the phase errors, and the third coefficient of the second adder may be variable to enable correction of the amplitude errors. ## Claims ### Claim 1 A system for correction of phase and amplitude errors, the system comprising: first and second adders each configured to supply, respectively, a first output signal and a second output signal, compute a sum of a first input signal and a second input signal, the sum being weighted via a respective first coefficient and a respective second coefficient, and multiply the weighted sum by a third coefficient; at least one of the first coefficient and the second coefficient of said first adder configured to enable correction of the phase errors using variable phase shift in terms of phase correction and a fixed amplitude correction; the third coefficient of said second adder configured to enable correction of the amplitude errors with a fixed phase shift in terms of phase correction and a variable amplitude correction. ### Claim 2 (depends on 1) The system according to claim 1 wherein the at least one of the first coefficient and the second coefficient of said first adder is variable to enable the correction of the phase errors; and wherein the third coefficient of said second adder is variable to enable the correction of the amplitude errors. ### Claim 3 (depends on 1) The system according to claim 1 wherein each of said first and second adders comprises an amplifier in an inverting mode; and wherein the first and second output signals are supplied by said respective amplifiers. ### Claim 4 (depends on 1) The system according to claim 1 wherein the first coefficient, the second coefficient, and the third coefficient are set via at least one of a resistor and a capacitor according to a switched-capacitor technique. ### Claim 5 (depends on 1) The system according to claim 1 wherein the first input signal is a differential signal; and wherein the second input signal is a differential signal. ### Claim 6 (depends on 1) The system according to claim 1 wherein the first input signal is an in-phase signal; and wherein the second input signal is a quadrature signal. ### Claim 7 (depends on 1) The system according to claim 1 wherein the first input signal and the second input signal are baseband signals. ### Claim 8 (depends on 1) The system according to claim 1 wherein for said first adder, only one between the first coefficient and the second coefficient is variable, and the other coefficient and the third coefficient are fixed to generate the variable phase shift in terms of phase correction and the fixed amplitude correction; and wherein for said second adder, only the third coefficient is variable, and the first coefficient and the second coefficient are fixed to generate the fixed phase shift in terms of phase correction and the variable amplitude correction. ### Claim 9 A receiver system comprising: a receiver circuit; and an error correction circuit coupled to said receiver circuit and for phase and amplitude correction, the error correction circuit comprising first and second adders each configured to supply, respectively, a first output signal and a second output signal, compute a sum of a first input signal and a second input signal, the sum being weighted via a respective first coefficient and a respective second coefficient, and multiply the weighted sum by a third coefficient; at least one of the first coefficient and the second coefficient of said first adder configured to enable correction of the phase errors using variable phase shift in terms of phase correction and a fixed amplitude correction; the third coefficient of said second adder configured to enable correction of the amplitude errors with a fixed phase shift in terms of phase correction and a variable amplitude correction. ### Claim 10 (depends on 9) The receiver system according to claim 9 wherein the at least one of the first coefficient and the second coefficient of said first adder is variable to enable the correction of the phase errors; and wherein the third coefficient of said second adder is variable to enable the correction of the amplitude errors. ### Claim 11 (depends on 9) The receiver system according to claim 9 wherein said system is configured to vary the first, second, and third coefficients of said first adder and of said second adder to correct the phase and amplitude errors between the first and second input signals. ### Claim 12 (depends on 9) The receiver system according to claim 9 wherein said receiver circuit is a receiver of the low-intermediate frequency type. ### Claim 13 (depends on 9) The receiver system according to claim 9 wherein each of said first and second adders comprises an amplifier in an inverting mode; and wherein the first and second output signals are supplied by said respective amplifiers. ### Claim 14 (depends on 9) The receiver system according to claim 9 wherein the first coefficient, the second coefficient, and the third coefficient are set via at least one of a resistor and a capacitor according to a switched-capacitor technique. ### Claim 15 (depends on 9) The receiver system according to claim 9 wherein the first input signal is a differential signal; and wherein the second input signal is a differential signal. ### Claim 16 A method for correction of phase and amplitude errors, the method comprising: operating each of first and second adders to supply, respectively, a first output signal and a second output signal, compute a sum of a first input signal and a second input signal, the sum being weighted via a respective first coefficient and a respective second coefficient, and multiply the weighted sum by a third coefficient; setting at least one of the first coefficient and the second coefficient of the first adder to enable correction of the phase errors using variable phase shift in terms of phase correction and a fixed amplitude correction; and setting the third coefficient of the second adder to enable correction of the amplitude errors with a fixed phase shift in terms of phase correction and a variable amplitude correction. ### Claim 17 (depends on 16) The method according to claim 16 further comprising varying the first, second, and third coefficients of the first adder and the second adder to enable the correction of the phase and amplitude errors between the first and second input signals. ### Claim 18 (depends on 16) The method according to claim 16 further comprising varying the at least one of the first coefficient and the second coefficient of the first adder to enable the correction of the phase errors, and varying the third coefficient of the second adder to enable the correction of the amplitude errors. ### Claim 19 (depends on 16) The method according to claim 16 wherein each of the first and second adders comprises an amplifier in an inverting mode; and wherein the first and second output signals are supplied by the respective amplifiers. ### Claim 20 (depends on 16) The method according to claim 16 wherein the first coefficient, the second coefficient, and the third coefficient are set via at least one of a resistor and a capacitor according to a switched-capacitor technique. ### Claim 21 (depends on 16) The method according to claim 16 wherein the first input signal is a differential signal; and wherein the second input signal is a differential signal.