Patents by Inventor Jayawardan Janardhanan
Jayawardan Janardhanan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 9841507Abstract: A wireless device for indoor positioning has a satellite positioning system, a transceiver, a motion measurement system, and a position estimation system. The satellite positioning system is configured to determine a location of the device based on received satellite positioning signals. The wireless local area network transceiver is configured to measure while in the areas of non-reception, signals transmitted by wireless local area network (WLAN) access points (APs). The motion measurement system is configured to measure movement of the wireless device. The position estimation system is configured to determine a reference location, and record measurements of movement. The reference location and the recorded measurements are to be provided to a positioning database that generates a positioning grid.Type: GrantFiled: March 23, 2015Date of Patent: December 12, 2017Assignee: TEXAS INSTRUMENTS INCORPORATEDInventors: Deric Wayne Waters, Jayawardan Janardhanan
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Publication number: 20170250693Abstract: A phase lock loop (PLL) includes a voltage-controlled oscillator (VCO) and a frequency detector to generate a FAST signal responsive to a frequency of a reference signal being greater than the frequency of a feedback signal derived from the VCO and to generate a SLOW signal responsive to the frequency of the reference signal being smaller than the frequency of the feedback signal. The PLL also includes a digital charge pump, a loop filter, and a state machine circuit. Responsive to receipt of multiple consecutive FAST signals when the digital charge pump is providing a charging current to the loop filter, the state machine circuit reconfigures the digital charge pump to increase the charging current to the loop filter. Responsive to receipt of multiple consecutive SLOW signals when the loop filter is discharging, the state machine circuit reconfigures the digital charge pump to cause the loop filter's discharge current to increase.Type: ApplicationFiled: February 27, 2017Publication date: August 31, 2017Applicant: TEXAS INSTRUMENTS INCORPORATEDInventors: Jayawardan JANARDHANAN, Krishnaswamy THIAGARAJAN, Jagdish Chand GOYAL
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Patent number: 9677905Abstract: Method including detecting low user dynamics by a first MEMS sensor is provided. A first sensor determines sampling rate value corresponding to the low user dynamics. The first sensor sampling rate value is less than a second sensor sampling rate value corresponding to high user dynamics. A sampling rate of a second MEMS sensor is adjusted to the first sensor sampling rate value.Type: GrantFiled: August 19, 2015Date of Patent: June 13, 2017Assignee: TEXAS INSTRUMENTS INCORPORATEDInventors: Deric Wayne Waters, Jayawardan Janardhanan, Saket Thukral
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Frequency synthesizer for achieving fast re-lock between alternate frequencies in low bandwidth PLLs
Patent number: 9667300Abstract: A frequency synthesizer that includes a reference frequency scaler and a phase locked loop (PLL) coupled to the reference frequency scaler. The reference frequency scaler is configured to generate a first reference frequency and a second reference frequency. The PLL is configured to generate a first output frequency based on the first reference frequency during a first timeslot and a second output frequency based on the second reference frequency during a second timeslot. The PLL comprises a loop filter that includes a first switch connected in series to a first capacitor and configured to close during the first timeslot and a second switch connected in series to a second capacitor and configured to open during the first timeslot.Type: GrantFiled: June 29, 2015Date of Patent: May 30, 2017Assignee: TEXAS INSTRUMENTS INCORPORATEDInventors: Jagdish Chand Goyal, Krishnaswamy Thiagarajan, Jayawardan Janardhanan, Srikanth Manian -
Publication number: 20160290807Abstract: A user-heading determining system (10) for pedestrian use includes a multiple-axis accelerometer (110) having acceleration sensors; a device-heading sensor circuit (115) physically situated in a fixed relationship to the accelerometer (110); an electronic circuit (100) operable to generate signals representing components of acceleration sensed by the accelerometer (110) sensors, and to electronically process at least some part of the signals to produce an estimation of attitude of a user motion with respect to the accelerometer, and further to combine the attitude estimation (750, ?) with a device heading estimation (770, ?) responsive to the device-heading sensor circuit, to produce a user heading estimation (780); and an electronic display (190) responsive to the electronic circuit (100) to display information at least in part based on the user heading estimation. Other systems, circuits and processes are also disclosed.Type: ApplicationFiled: May 10, 2016Publication date: October 6, 2016Inventors: Jayawardan Janardhanan, Goutam Dutta, Varun Tripuraneni
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Patent number: 9391653Abstract: Undesired variations in a signal are removed by initializing two boundaries comprising an upper boundary and a lower boundary to track the signal level. At least one of the upper boundary and the lower boundary is adjusted encapsulate/track the received signal between the two boundaries when the signal level is outside of the two boundaries. A value computed with reference to at least one of the boundaries is provided as a filter output. As a result, the output comprises desired variations that cross the boundaries and the undesired variations that are within the boundaries are eliminated. In one embodiment, an altimeter sensor signal is filtered such that the undesired variations due to noise and instability of the altimeter are removed and the desired variations representing the change in the altitude are detected and provided without any delay to the navigation subsystem.Type: GrantFiled: May 13, 2013Date of Patent: July 12, 2016Assignee: Texas Instruments IncorporatedInventor: Jayawardan Janardhanan
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Patent number: 9383209Abstract: According to an aspect of the present disclosure, the relative attitude between an inertial measurement unit (IMU), present on a mobile device, and the frame of reference of the vehicle carrying mobile device is estimated. The estimated relative attitude is used to translate the IMU measurement to the vehicle frame of reference to determine the velocity and position of the vehicle. As a result, the vehicle position and velocity are determined accurately in the event of undocking and re-docking of the mobile device from a docking system in the vehicle. The relative attitude is estimated in terms of pitch, roll, and yaw angles.Type: GrantFiled: September 23, 2013Date of Patent: July 5, 2016Assignee: Texas Instruments IncorporatedInventors: Sachin Bhardwaj, Sriram Murali, Jaiganesh Balakrishnan, Jayawardan Janardhanan, Yogesh Shekar, Goutam Dutta
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Patent number: 9360324Abstract: A user-heading determining system (10) for pedestrian use includes a multiple-axis accelerometer (110) having acceleration sensors; a device-heading sensor circuit (115) physically situated in a fixed relationship to the accelerometer (110); an electronic circuit (100) operable to generate signals representing components of acceleration sensed by the accelerometer (110) sensors, and to electronically process at least some part of the signals to produce an estimation of attitude of a user motion with respect to the accelerometer, and further to combine the attitude estimation (750, ?) with a device heading estimation (770, ?) responsive to the device-heading sensor circuit, to produce a user heading estimation (780); and an electronic display (190) responsive to the electronic circuit (100) to display information at least in part based on the user heading estimation. Other systems, circuits and processes are also disclosed.Type: GrantFiled: July 21, 2015Date of Patent: June 7, 2016Assignee: Texas Instruments IncorporatedInventors: Jayawardan Janardhanan, Goutam Dutta, Varun Tripuraneni
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Publication number: 20160138923Abstract: A user-heading determining system (10) for pedestrian use includes a multiple-axis accelerometer (110) having acceleration sensors; a device-heading sensor circuit (115) physically situated in a fixed relationship to the accelerometer (110); an electronic circuit (100) operable to generate signals representing components of acceleration sensed by the accelerometer (110) sensors, and to electronically process at least some part of the signals to produce an estimation of attitude of a user motion with respect to the accelerometer, and further to combine the attitude estimation (750, ?) with a device heading estimation (770, ?) responsive to the device-heading sensor circuit, to produce a user heading estimation (780); and an electronic display (190) responsive to the electronic circuit (100) to display information at least in part based on the user heading estimation. Other systems, circuits and processes are also disclosed.Type: ApplicationFiled: July 21, 2015Publication date: May 19, 2016Inventors: Jayawardan Janardhanan, Goutam Dutta, Varun Tripuraneni
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Publication number: 20160054146Abstract: A system comprises a plurality of sensors, a sensor processor, and a sampling rate engine. The sensor processor is coupled to an output of each sensor of the plurality of sensors. The sensor processor estimates user dynamics in response to a first output signal of a first sensor of the plurality of sensors. The sampling rate engine is coupled to an output of the sensor processor./ The sampling rate engine determines a sampling rate value of a second sensor of the plurality of sensors in response to a user dynamics value from the sensor processor. The second sensor comprises a selectable sampling rate. The selectable sampling rate is configured in response to the sampling rate value determined by the sampling rate engine.Type: ApplicationFiled: August 19, 2015Publication date: February 25, 2016Inventors: Deric Wayne Waters, Jayawardan Janardhanan, Saket Thukral
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Publication number: 20160041013Abstract: Method including detecting low user dynamics by a first MEMS sensor is provided. A first sensor determines sampling rate value corresponding to the low user dynamics. The first sensor sampling rate value is less than a second sensor sampling rate value corresponding to high user dynamics. A sampling rate of a second MEMS sensor is adjusted to the first sensor sampling rate value.Type: ApplicationFiled: August 19, 2015Publication date: February 11, 2016Inventors: Deric Wayne Waters, Jayawardan Janardhanan, Saket Thukral
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Publication number: 20160003622Abstract: Devices and methods for pedestrian navigation are disclosed. In an embodiment, a device includes an accelerometer sensor configured to sense acceleration components associated with a device motion in a plurality of axes of the accelerometer sensor. The acceleration components include stride frequency components and step frequency components. The device includes a processing module communicably associated with the accelerometer sensor. The processing module is configured to process at least a portion of the acceleration components to determine an estimated attitude associated with the device motion with respect to the accelerometer sensor. The processing module is configured to filter out the step frequency components by blocking the stride frequency components. The processing module is further configured to determine the estimated attitude based on the step frequency components to thereby mitigate a bias in the estimated attitude associated with a lateral sway of the device motion.Type: ApplicationFiled: July 3, 2014Publication date: January 7, 2016Inventors: JAYAWARDAN JANARDHANAN, Jaiganesh Balakrishnan
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FREQUENCY SYNTHESIZER FOR ACHIEVING FAST RE-LOCK BETWEEN ALTERNATE FREQUENCIES IN LOW BANDWIDTH PLLS
Publication number: 20150381190Abstract: A frequency synthesizer that includes a reference frequency scaler and a phase locked loop (PLL) coupled to the reference frequency scaler. The reference frequency scaler is configured to generate a first reference frequency and a second reference frequency. The PLL is configured to generate a first output frequency based on the first reference frequency during a first timeslot and a second output frequency based on the second reference frequency during a second timeslot. The PLL comprises a loop filter that includes a first switch connected in series to a first capacitor and configured to close during the first timeslot and a second switch connected in series to a second capacitor and configured to open during the first timeslot.Type: ApplicationFiled: June 29, 2015Publication date: December 31, 2015Inventors: Jagdish Chand GOYAL, Krishnaswamy THIAGARAJAN, Jayawardan JANARDHANAN, Srikanth MANIAN -
Patent number: 9140590Abstract: At least some of the embodiments are methods including detecting low user dynamics by a first MEMS sensor, determining a first sensor sampling rate value corresponding to the low user dynamics wherein the first sensor sampling rate value is less than a second sensor sampling rate value corresponding to high user dynamics, and adjusting a sampling rate of a second MEMS sensor to the first sensor sampling rate value.Type: GrantFiled: September 27, 2013Date of Patent: September 22, 2015Assignee: TEXAS INSTRUMENTS INCORPORATEDInventors: Deric Wayne Waters, Jayawardan Janardhanan, Saket Thukral
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Patent number: 9121714Abstract: A user-heading determining system (10) for pedestrian use includes a multiple-axis accelerometer (110) having acceleration sensors; a device-heading sensor circuit (115) physically situated in a fixed relationship to the accelerometer (110); an electronic circuit (100) operable to generate signals representing components of acceleration sensed by the accelerometer (110) sensors, and to electronically process at least some part of the signals to produce an estimation of attitude of a user motion with respect to the accelerometer, and further to combine the attitude estimation (750, ?) with a device heading estimation (770, ?) responsive to the device-heading sensor circuit, to produce a user heading estimation (780); and an electronic display (190) responsive to the electronic circuit (100) to display information at least in part based on the user heading estimation. Other systems, circuits and processes are also disclosed.Type: GrantFiled: February 14, 2014Date of Patent: September 1, 2015Assignee: TEXAS INSTRUMENTS INCORPORATEDInventors: Jayawardan Janardhanan, Goutam Dutta, Varun Tripuraneni
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Patent number: 9103916Abstract: Apparatus and method for positioning a wireless device. In one embodiment, a method for indoor positioning includes determining a reference location of a wireless device, based on satellite positioning, as the device passes between areas of satellite positioning signal reception and satellite positioning signal non-reception. While in the areas of non-reception, signals transmitted by wireless local area network (WLAN) access points (APs) and parameters of motion of the device are measured. Positions of the device are estimated while in the areas of non-reception based on the reference location and the parameters of motion. A positioning grid for positioning is generated based on the signals measured by the wireless device at the estimated positions.Type: GrantFiled: May 2, 2012Date of Patent: August 11, 2015Assignee: TEXAS INSTRUMENTS INCORPORATEDInventors: Deric W. Waters, Jayawardan Janardhanan
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Publication number: 20150198695Abstract: A wireless device for indoor positioning has a satellite positioning system, a transceiver, a motion measurement system, and a position estimation system. The satellite positioning system is configured to determine a location of the device based on received satellite positioning signals. The wireless local area network transceiver is configured to measure while in the areas of non-reception, signals transmitted by wireless local area network (WLAN) access points (APs). The motion measurement system is configured to measure movement of the wireless device. The position estimation system is configured to determine a reference location, and record measurements of movement. The reference location and the recorded measurements are to be provided to a positioning database that generates a positioning grid.Type: ApplicationFiled: March 23, 2015Publication date: July 16, 2015Inventors: Deric Wayne Waters, Jayawardan Janardhanan
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Publication number: 20150198694Abstract: A positioning server has a positioning database. The positioning database is configured to store information relating wireless local area network (WLAN) access point (AP) signal measurements to points of a geographic positioning grid. motion information provided by dead-reckoning systems of a plurality of wireless devices and reference location information provided by at least one of a satellite positioning system and a wireless local area network (WLAN) positioning system of each wireless device is also stored. WLAN access point (AP) signal measurements acquired by each wireless device in correspondence with the motion information is stored as are non-causally determine positions of the wireless devices based on the motion information and reference locations. Positioning server is also configured to generate a geographic positioning grid that relates the AP signal measurements to points of the positioning grid based on the determined positions.Type: ApplicationFiled: March 24, 2015Publication date: July 16, 2015Inventors: Deric Wayne Waters, Jayawardan Janardhanan
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Publication number: 20150198721Abstract: A system for crowd-sourced fingerprinting has a positioning database and a mobile wireless device. The positioning database is configured to store information relating wireless local area network access point (AP) signal measurements to points of a geographic positioning grid. The mobile wireless device has a satellite positioning system, a transceiver, a motion measurement system, and position estimation logic. The position estimation logic is configured to determine a reference location as the device passes between areas of satellite positioning signal reception and satellite positioning signal non-reception. The device further configured to record measurements of movements provided by the motion measurement system and measurements of signals provided by the transceiver within areas of non-reception and to provide results to the positioning database.Type: ApplicationFiled: March 24, 2015Publication date: July 16, 2015Inventors: Deric Wayne Waters, Jayawardan Janardhanan
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Publication number: 20150088419Abstract: According to an aspect of the present disclosure, the relative attitude between an inertial measurement unit (IMU), present on a mobile device, and the frame of reference of the vehicle carrying mobile device is estimated. The estimated relative attitude is used to translate the IMU measurement to the vehicle frame of reference to determine the velocity and position of the vehicle. As a result, the vehicle position and velocity are determined accurately in the event of undocking and re-docking of the mobile device from a docking system in the vehicle. The relative attitude is estimated in terms of pitch, roll, and yaw angles.Type: ApplicationFiled: September 23, 2013Publication date: March 26, 2015Applicant: Texas Instruments IncorporatedInventors: Sachin Bhardwaj, Sriram Murali, Jaiganesh Balakrishnan, Jayawardan Janardhanan, Yogesh Shekar, Goutam Dutta