Estimation of signal parameters in radio channels by rotational invariance techniques involves transmission of test signals at intervals and use of test algorithm and complex amplitude values

摘要

The test signal may be spread and distorted by multipath transmission. The radio receiver has a number of individual antenna elements to receive overlapping test signals. Delay times are noted and a minimum distance search may be instituted. Reflection chains may be detected and approximated using a polynomial. The test procedure may be used with GPS and broadband systems.