Channel Characterization for EHF Satellite Communications on the Move
Abstract
In addition to long signal propagation delays, the mobile satellite terminal in a land-mobile satellite communications system is subject to channel impairments imposed by the terrestrial environment. Statistical channel models are needed for protocol development and performance evaluation of systems for satellite communications (SATCOM) on the move. Experimental measurements were made in and around Boston, MA, using a prototype system for SATCOM on the move. The measurements characterize the 20 GHz down-link signal and were made in the fall and winter months of 2004. The elevation angle to the satellite was approximately 360. This report covers the measurement campaign, initial single-terminal channel modeling. and multi-terminal channel models relevant for cooperating ground terminals. The data sets are analyzed for the statistical properties of the channel state. The channel is considered to be "open" when a clear path exists to the satellite and "blocked" when there is an obstruction in the path that prevents the successful transfer of information from transmitter to receiver. For the single-channel analysis. three operational environments were previously classified as urban, rural, or open. We propose two new operational categories: open highway and dense urban. The addition of these categories is based on a natural partitioning of the experimental data. The open highway channel model contains very long open intervals, 310 m on average, and is blocked 5% of the time. The dense urban environment, on the other hand, consists of tall, closely spaced buildings. In this environment, the average blockage duration is 130 m and the channel is blocked 89% of the time. We evaluate the suitability of Markov state models to accurately reflect the channel behavior.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 12, 2006
- Accession Number
- ADA454988
Entities
People
- W. M. Smith
Organizations
- Massachusetts Institute of Technology