Absolute Position Encoder Using Temporal Multiplexing

The patent transitions from using multiple parallel scale tracks (spatial dimension) to using a single scale track with temporal signal cycling (time dimension). The readhead processor generates multiple signal cycles (first cycle, second cycle, third cycle) with different excitations and measurements taken at different times, effectively moving the problem from spatial multiplexing to temporal multiplexing.

The patent employs periodic signal cycles where the readhead processor repeatedly excites the scale track with different patterns (first excitation, second excitation, third excitation) and measures responses at regular intervals. This periodic action allows the system to extract multiple position signals from a single scale track over time, replacing the need for multiple simultaneous tracks.

The system uses periodic signal cycles where only one scale track is actively excited at any given time. The readhead processor sequentially generates first, second, and third signal cycles with different excitations, measuring responses at different times. This time-multiplexed approach ensures that power-consuming excitations are distributed over time rather than occurring simultaneously, reducing peak and average power consumption compared to multiple continuously active tracks.

The system dynamically switches between different excitation patterns and measurement modes across multiple signal cycles. The readhead processor adapts its operation by generating different types of excitations (first excitation, second excitation, third excitation) and selecting appropriate measurement sequences, allowing optimal power management while maintaining measurement precision through intelligent temporal sequencing.

The patent compensates for reduced signal strength from a single scale track by employing multiple periodic signal cycles with different excitations. The readhead processor generates first, second, and third signal cycles, each with specific excitations and measurements. By accumulating and processing signals from multiple cycles, the system enhances the effective signal strength and improves position determination accuracy despite using only one scale track.

The system maintains continuous position measurement capability through overlapping signal cycles. The first, second, and third signal cycles are designed to provide continuous position information, with measurements taken at different times but contributing to the overall position determination. This continuous action ensures that signal strength is maintained through temporal integration rather than spatial redundancy.