公开(公告)号：US20190214972A1

公开(公告)日：2019-07-11

申请号：US16299299

申请日：2019-03-12

Applicant: Texas Instruments Incorporated

Inventor： Jaiganesh Balakrishnan ,  Sthanunathan Ramakrishnan ,  Pooja Sundar ,  Sashidharan Venkatraman

IPC: H03H17/02 ,  G06F5/01 ,  H03M1/06 ,  G06F7/544 ,  H03H17/00 ,  H03H17/06

CPC classification number: H03H17/0219 ,  G06F5/01 ,  G06F7/5443 ,  H03H17/0045 ,  H03H17/06 ,  H03M1/0626 ,  H03M1/12 ,  H03M1/1215

Abstract: In accordance with an example, an integrated circuit includes a linear combiner having an input for receiving a signal. The linear combiner also has a plurality of operator circuits for applying weighting factors to the signal, in which a first operator circuit in the plurality of operator circuits performs a first operation on the signal using a first sub-weight of one of the weighting factors to provide a first tile output and a second operator circuit in the plurality of operator circuits performs a second operation on the signal using a second sub-weight of the one of the weighting factors to provide a second tile output. The linear combiner also has an adder having a first input coupled to receive the first tile output and the second tile outputs and providing a combined output.

公开(公告)号：US20170324421A1

公开(公告)日：2017-11-09

申请号：US15389236

申请日：2016-12-22

Applicant: Texas Instruments Incorporated

Inventor： Jawaharlal Tangudu ,  Sthanunathan Ramakrishnan ,  Nagarajan Viswanathan ,  Pooja Sundar

IPC: H03M1/06 ,  H03M1/12 ,  H03M1/10

CPC classification number: H03M1/0617 ,  H03M1/1009 ,  H03M1/1042 ,  H03M1/1215 ,  H03M1/1245

Abstract: Methods and apparatus for reducing non-linearity in analog to digital converters are disclosed. An example apparatus includes an analog-to-digital converter to convert an analog signal into a digital signal; and a non-linearity corrector coupled to the analog-to-digital converter to determine a derivative of the digital signal; determine cross terms including a combination of the digital signal and the derivative of the digital signal; and determine a non-linearity term corresponding to a combination of the cross terms.

公开(公告)号：US20140159950A1

公开(公告)日：2014-06-12

申请号：US13710154

申请日：2012-12-10

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Atul Deshpande ,  Sthanunathan Ramakrishnan ,  Sandeep Rao

IPC: G01S19/40

CPC classification number: G01S19/40 ,  G01S5/0294 ,  G01S19/22 ,  G01S19/49

Abstract: A Global Navigation Satellite System (GNSS) receiver determines a measurement error covariance from a reference position and a set of measured pseudoranges from a set of GNSS satellites. The position and velocity solution is determined from the measurement error covariance and the set of measured pseudoranges. The measurement error covariance is determined as function of the difference between a reference pseudorange and measured pseudorange. The reference pseudorange is computed from the reference position to a satellite. The measurement error covariance is determined as function of the difference only if the measured pseudorange is greater than the reference pseudorange. The GNSS receiver also determines measurement error covariance as function of one or more of correlation peak shape, difference, the correlation peak shape, a received signal to noise ratio and a tracking loop error.

Abstract translation: 全球导航卫星系统（GNSS）接收机从一组GNSS卫星确定来自参考位置和一组测量伪距的测量误差协方差。 位置和速度解是从测量误差协方差和测量伪距的集合确定的。 测量误差协方差被确定为参考伪距和测量伪距之间的差的函数。 从参考位置到卫星计算参考伪距。 仅当所测量的伪距大于参考伪距时，测量误差协方差才被确定为差值的函数。 GNSS接收机还将测量误差协方差确定为相关峰形，差，相关峰形，接收信噪比和跟踪循环误差中的一个或多个的函数。

公开(公告)号：US11095485B2

公开(公告)日：2021-08-17

申请号：US16695586

申请日：2019-11-26

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Jawaharlal Tangudu ,  Sashidharan Venkatraman ,  Sundarrajan Rangachari ,  Sarma Sundareswara Gunturi ,  Sthanunathan Ramakrishnan

IPC: H04B1/00 ,  H04L25/03 ,  H04L25/02

Abstract: An electrical system includes a transceiver with an IQ estimator and an IQ mismatch corrector. The electrical system also includes an antenna coupled to the transceiver. The IQ estimator is configured to perform frequency-domain IQ mismatch analysis to determine an IQ mismatch estimate at available frequency bins of a baseband data signal. The IQ mismatch corrector is configured to correct the baseband data signal based on the IQ mismatch estimate.

公开(公告)号：US10924320B2

公开(公告)日：2021-02-16

申请号：US16525103

申请日：2019-07-29

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Sthanunathan Ramakrishnan ,  Chandrasekhar Sriram ,  Raju Kharataram Chaudhari

IPC: H04L27/36 ,  H03D3/00 ,  H04B1/30 ,  H04L27/38

Abstract: An IQ estimation module comprising a powerup state IQ estimator configured to generate powerup state IQ estimates based on a powerup calibration of the IQ estimation module, a steady state IQ estimator configured to generate steady state IQ estimates during a steady state operation of the IQ estimation module, and an IQ estimate extender configured to determine differences between the powerup state IQ estimates and steady state IQ estimates at their respective frequency bins and adjust the powerup state IQ estimates to improve the accuracy of IQ estimates.

公开(公告)号：US10812294B2

公开(公告)日：2020-10-20

申请号：US16684842

申请日：2019-11-15

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Jawaharlal Tangudu ,  Sashidharan Venkatraman ,  Sarma Sundareswara Gunturi ,  Chandrasekhar Sriram ,  Sthanunathan Ramakrishnan ,  Ram Narayan Krishna Nama Mony

IPC: H03H7/30 ,  H03H7/40 ,  H03K5/159 ,  H04L25/02 ,  H04B1/02 ,  H04B17/11

Abstract: A channel estimation method and system for IQ imbalance and local oscillator leakage correction, wherein an example of a channel estimation system comprising a calibrating signal generator configured to generate at least one pair of calibrating signals, a feedback IQ mismatch estimator configured to measure feedback IQ mismatch estimates based on the pair of calibrating signals, and a calibrating signal based channel estimator configured to generate a channel estimate based on the pair of calibrating signals and the feedback IQ mismatch estimates.

公开(公告)号：US10277202B2

公开(公告)日：2019-04-30

申请号：US15645647

申请日：2017-07-10

Applicant: Texas Instruments Incorporated

Inventor： Jaiganesh Balakrishnan ,  Sthanunathan Ramakrishnan ,  Pooja Sundar ,  Sashidharan Venkatraman

IPC: H03H17/02 ,  H03H17/00 ,  G06F5/01 ,  G06F7/544 ,  H03H17/06 ,  H03M1/06 ,  H03M1/12

Abstract: In accordance with an example, an integrated circuit includes a linear combiner having an input for receiving a signal. The linear combiner also has a plurality of operator circuits for applying weighting factors to the signal, in which a first operator circuit in the plurality of operator circuits performs a first operation on the signal using a first sub-weight of one of the weighting factors to provide a first tile output and a second operator circuit in the plurality of operator circuits performs a second operation on the signal using a second sub-weight of the one of the weighting factors to provide a second tile output. The linear combiner also has an adder having a first input coupled to receive the first tile output and the second tile outputs and providing a combined output.

公开(公告)号：US09513374B2

公开(公告)日：2016-12-06

申请号：US13710154

申请日：2012-12-10

Applicant: Texas Instruments Incorporated

Inventor： Atul Deshpande ,  Sthanunathan Ramakrishnan ,  Sandeep Rao

IPC: G01S19/40 ,  G01S19/22 ,  G01S19/49 ,  G01S5/02

CPC classification number: G01S19/40 ,  G01S5/0294 ,  G01S19/22 ,  G01S19/49

Abstract: A Global Navigation Satellite System (GNSS) receiver determines a measurement error covariance from a reference position and a set of measured pseudoranges from a set of GNSS satellites. The position and velocity solution is determined from the measurement error covariance and the set of measured pseudoranges. The measurement error covariance is determined as function of the difference between a reference pseudorange and measured pseudorange. The reference pseudorange is computed from the reference position to a satellite. The measurement error covariance is determined as function of the difference only if the measured pseudorange is greater than the reference pseudorange. The GNSS receiver also determines measurement error covariance as function of one or more of correlation peak shape, difference, the correlation peak shape, a received signal to noise ratio and a tracking loop error.

Abstract translation: 全球导航卫星系统（GNSS）接收机从一组GNSS卫星确定来自参考位置和一组测量伪距的测量误差协方差。 位置和速度解是从测量误差协方差和测量伪距的集合确定的。 测量误差协方差被确定为参考伪距和测量伪距之间的差的函数。 从参考位置到卫星计算参考伪距。 仅当所测量的伪距大于参考伪距时，测量误差协方差才被确定为差值的函数。 GNSS接收机还将测量误差协方差确定为相关峰形，差，相关峰形，接收信噪比和跟踪循环误差中的一个或多个的函数。

公开(公告)号：US20160344400A1

公开(公告)日：2016-11-24

申请号：US15145375

申请日：2016-05-03

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Sthanunathan Ramakrishnan ,  Sashidharan Venkatraman ,  Jaiganesh Balakrishnan

IPC: H03M1/06 ,  H03M1/10 ,  H03M1/12

CPC classification number: H03M1/0626 ,  H03M1/1009 ,  H03M1/1215

Abstract: Methods, apparatus, systems and articles of manufacture to increase an integrity of mismatch corrections in an interleaved analog to digital converter are disclosed. An example apparatus includes an instantaneous mismatch estimator that uses an output of an interleaved analog to digital converter to identify a mismatch estimate between two or more component analog to digital converters of the interleaved analog to digital converter. An integrity monitor is to cause the instantaneous mismatch estimator to avoid incorrectly providing the mismatch estimate to a filter, the integrity monitor to instruct the filter to remove the mismatch estimate when the mismatch estimate is detected to be inaccurate.

Abstract translation: 公开了用于增加交错模数转换器中的失配校正的完整性的方法，装置，系统和制品。 一个示例性装置包括瞬时失配估计器，其使用交错模数转换器的输出来识别交错模数转换器的两个或多个分量模数转换器之间的失配估计。 完整性监视器是使瞬时失配估计器避免错误地向滤波器提供不匹配估计，当检测到不匹配估计不准确时，完整性监视器指示滤波器去除失配估计。

公开(公告)号：US09178525B2

公开(公告)日：2015-11-03

申请号：US14656122

申请日：2015-03-12

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Sthanunathan Ramakrishnan ,  Sreenath Narayanan Potty

IPC: H03M1/10 ,  H03M1/12 ,  H03M1/06

CPC classification number: H03M1/121 ,  H03M1/06 ,  H03M1/0626 ,  H03M1/0639 ,  H03M1/1205 ,  H03M1/1215

Abstract: A mismatch corrector can include a correction path comprising a plurality of parallel branches that each includes a correction filter that applies a respective one of a plurality of time domain filter coefficients that corresponds to a function of a mismatch profile of an interleaved analog-to-digital (IADC) signal on the IADC signal. The mismatch corrector can also include a delay path that delays the IADC signal by a predetermined number of samples to provide a delayed version of the IADC signal. The mismatch corrector can further include a summer to subtract an output of each correction filter from the delayed version of the IADC signal to generate a corrected IADC signal.

Abstract translation: 不匹配校正器可以包括校正路径，其包括多个并行分支，每个分支包括校正滤波器，校正滤波器应用与交织的模数转换器的失配曲线的函数相对应的多个时域滤波器系数中的相应一个 （IADC）信号。 不匹配校正器还可以包括将IADC信号延迟预定数量的采样以提供IADC信号的延迟版本的延迟路径。 不匹配校正器还可以包括加法器，以从IADC信号的延迟版本中减去每个校正滤波器的输出，以产生校正的IADC信号。