A Comprehensive Investigation of Advanced Range Telemetry
Abstract
This report summarizes the results of the initial work on channel characterization for the Advanced Range Telemetry (ARTM) program. Data collected from channel sounding flights was used to determine the number, complex gain, and delays of multipath propagation paths that distort the received signal in common aeronautical telemetry scenarios. These parameters were estimated using frequency domain curve fitting techniques to describe significant number of multipath fade events recorded during channel sounding flights. The results were compared with time-domain cross correlation estimation techniques where applicable and found to be consistent. The physical geometry of the multipath environment was also analyzed where it was shown that the multipath delays derived from the data analysis were consistent with those that could have been produced by the transmitter/receiver geometry. Both static channel models and dynamic channel models were evaluated. The static channel model consists of three propagation paths: a line-of-sight path; a strong specular reflection with an amplitude greater than 50% that of the line-of-sight path and delay 30 to 70 nanoseconds; and a weaker specular reflection with an amplitude less than 50% that of the line-of-sight path and a delay 175 to 325 nanoseconds. The dynamic channel model depends on the scattering function and Doppler spectrum. These functions were estimated from the data where it was found that the spatial sampling rate on the channel sounding flights to date was not sufficiently fast to capture the frequency content associated with the changes in the channel impulse response. The resulting Doppler spectra were obviously aliased.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 29, 1999
- Accession Number
- ADA375937
Entities
People
- Michael Rice
Organizations
- Brigham Young University