WORKSHOP PAPER
Range ambiguity cancellation for continuous-wave indirect ToF image sensors
Abstract
We propose a method for range ambiguity cancellation to eliminate phase wrapping errors in indirect time-of-flight (iToF) systems. The method introduces the concept of random packet modulation combined with an ambiguity mask algorithm. A new indicator of the normalized amplitude has been introduced to effectively cancel out depth signals outside an unambiguous range with only a single depth frame. When combined with the random packet modulation, this normalized amplitude can extend the minimum detectable object reflectivity by 14%p, compared to conventional iToF. This technique reduces motion artifacts by 75% compared to the dual-frequency method, enabling the generation of a depth image using a single modulation frequency.Keywords
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