Comparison of the one-way and commonview GPS measurement techniques using a known frequency offset

Calibration and testing laboratories are seldom required to measure or certify signals with frequency offsets smaller than 1 × 10-12. To compare the suitability of the one-way and common-view measurement techniques for calibration laboratories, we generate a 10 MHz test signal with a frequency offset of 10 µHz (1 × 10-12 offset) with respect to the UTC (NIST) time scale. We then compare the 10 MHz test signal directly to UTC (NIST) with a time interval counter, to the Global Positioning System (GPS) using the one-way measurement technique, and to UTC (NIST) using a multi-channel all-in-view common-view GPS measurement technique over a baseline of 6.2 m. The experiment is repeated using test signals with 4 µHz (4 × 10-13) and 1 µHz (1 × 10-13) frequency offsets, and the results are summarized and compared