2results about How to "Avoid mutual coupling" patented technology

This invention discloses a six-degree-of-freedom laser measurement system belonging to the field of precision measurement technology. It includes a laser source, a collimating and beam-expanding lens, three beam-splitting prisms, a reflector, a cross-shaped circular reflective target, two focusing lenses, three CCD cameras, and a telecentric lens. Based on the different degrees of freedom being measured, it is divided into a first optical system, a second optical system, and a third optical system. The first optical system uses the principle of oblique-shot laser triangulation to measure the displacement of the object along the Z-axis. The second optical system uses the principle of self-collimation to measure the rotation angles of the object along the X and Y axes. The third optical system uses the principle of visual imaging to measure the displacement of the object along the X and Y axes and the rotation angle along the Z-axis. This invention employs an optical path multiplexing mechanism, significantly reducing the number of components and achieving system miniaturization, integration, and low cost. The six degrees of freedom are measured independently, avoiding coupling relationships between them.

The application discloses a hierarchical background calibration method for a time-interleaved ADC (Analog to Digital Converter), which is suitable for a multi-channel time-interleaved and single-channel two-stage ADC structure analog-digital conversion system. After code conversion and data alignment of each sub-channel output code stream, the method firstly estimates and eliminates each channel misadjustment and mismatch by using a second-order digital tracking loop after down-sampling, then constructs a gain error iterative update loop based on channel output power consistency to obtain a digital gain compensation coefficient, and finally performs same-frequency quadrature demodulation on each channel sequence after misadjustment and gain correction, extracts each channel phase information and converts it into a relative sampling time sequence deviation, and quantitatively compensates through a programmable clock delay unit. The method classifies static mismatch and dynamic time sequence mismatch, can suppress interleaving spur without interrupting normal sampling, improves the SNDR (Signal-to-Noise and Distortion Ratio) and SFDR (Spurious Free Dynamic Range) of the time-interleaved ADC, is simple in hardware implementation, is suitable for RTL (Register Transfer Level) implementation and on-chip background operation.