| Autor: |
Kast JM; National Institute of Standards and Technology (NIST), Communication Technology Laboratory, Boulder, CO 80305 USA., Rezac JD; National Institute of Standards and Technology (NIST), Communication Technology Laboratory, Boulder, CO 80305 USA., Römisch S; National Institute of Standards and Technology (NIST), Communication Technology Laboratory, Boulder, CO 80305 USA., Elsherbeni AZ; Electrical Engineering Department, Colorado School of Mines, Golder, CO 80401 USA., Quimby JT; National Institute of Standards and Technology (NIST), Communication Technology Laboratory, Boulder, CO 80305 USA. |
| Abstrakt: |
We describe a mathematical framework for evaluating timing offset and timing noise in channel sounders based on a second-order deterministic model and a stochastic metric based on the Allan Deviation. Using this framework, we analyze the timing offset and noise for a 1-6 GHz correlation-based channel sounder that uses rubidium clocks to provide a common timebase between the transmitter and receiver. We study timing behavior in three clock-distribution configurations. In the "untethered" configuration, the transmitter and receiver each have a rubidium clock, and no physical timing cable is connected between the clocks. In the "tethered" configuration, a coaxial cable synchronizes timing between the two separate clocks. Finally, a benchmark "single-clock" configuration is used where a single rubidium clock drives the transmitter and receiver. |
