Abstract: An Ethernet-compatible synchronization process between isolated digital data streams assures synchronization by embedding an available time code from a first stream into data locations in a second stream that are known a priori to be unneeded. Successive bits of time code values, generated as a step in acquiring and digitizing analog sensor data, are inserted into least-significant-bit locations in a digitized audio stream generated along with digitized image data by a digital video process. The overwritten LSB locations are shown to have no discernable effect on audio reconstructed from the Ethernet packets. Telemetry recovery is the reverse of the embedment process, and the data streams are readily synchronized by numerical methods.

Abstract: A digital data bandpass filter process using digital signal processing processes raw digital data twice using distinct all-pass filters, wherein the two filters perform different frequency-dependent phase shifts of the digital content. The two filter output streams may be subtracted to remove out-of-band energy. The process produces lower levels of noise and conversion artifacts when used for filtering fixed-point data that may have low energy, and thus few non-zero bits, in the analog input signals, than conventional digital bandpass filters.