Method for calibration of a system with time-multiplexed sensors

• US 9,939,290 B1
• Filed: 04/13/2015
• Issued: 04/10/2018
• Est. Priority Date: 09/16/2013
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Rout, Saroj J., Garlapati, Akhil K., Yu, Qicheng
• Primary Examiner(s): KWOK, HELEN C
• Application Number:
  US14/685,139
• Time in Patent Office: 1,093 Days
• CPC Class Codes: G01C 19/5726 Signal processing
• CPC Class Codes: G01C 19/5776 Signal processing not specific to any of the devices covered by groups G01C19/5607 - G01C19/5719
• CPC Class Codes: G01C 25/005 initial alignment, calibration or starting-up of inertial devices
• CPC Class Codes: G01D 3/032 affecting incoming signal, e.g. by averaging; gating undesired signals
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: G01P 21/00 Testing or calibrating of apparatus or devices covered by the preceding groups
• CPC Class Codes: H04Q 11/04 for time-division multiplexing H04Q11/0001 takes precedence
• CPC Class Codes: H04Q 2213/13213 Counting, timing circuits
• CPC Class Codes: H04Q 2213/13292 Time division multiplexing, TDM
• CPC Class Codes: H04Q 2213/13305 Transistors, semiconductors in general
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A sense channel signal processing block is time-domain multiplexed among multiple MEMS devices and utilizes an anti-aliasing filter disposed after track-and-hold switches, to prevent the bandwidth of the sense channel from being limited by the anti-aliasing filter. A multiplexed signal processor architecture performs dynamic calibration of all sensor error signals in response to environmental changes.

Claims

1. A sense channel apparatus comprising:

a) a plurality of input switches for receiving analog signals from a plurality of MEMS devices, respectively;

b) a plurality of output switches;

c) a zero-IF mixer operatively coupled intermediate the plurality of input switches and the plurality of output switches;

d) a common signal processing module operatively coupled intermediate the zero-IF mixer and the plurality of output switches, the signal processing module configured to at least partially derive a parameter signal from an analog signal from one of the plurality of MEMS devices; and

e) a calibration module configured to generate a calibration signal at least partially derived from the parameter signal associated with one of the plurality of MEMS devices and further configured to provide the generated calibration signal to one of the plurality of MEMS devices in a multiplexed, time domain manner, wherein calibration signals are generated for the plurality of MEMS devices, respectively.

2. The apparatus of claim 1, wherein the zero-IF mixer has a trans-impedance amplifier.

3. The apparatus of claim 2 wherein at least one of the MEMS devices comprises a gyroscope.

4. The apparatus of claim 1 further comprising a timing generator module for providing timing signals to the signal processing module and the calibration module.

5. The apparatus of claim 1, wherein the calibration signal is updated to a particular MEMS device of the plurality of the MEMS devices during a phase when an output of the particular MEMS device is inactive.