author = {M. Feng and K.-D. Kammeyer},
  year = {1998},
  month = {Sep},
  title = {Modified Subspace Smoothing Technique for Multipath Direction Finding},
  publisher = {1},
  pages = {181-184},
  URL = {http://cgi.di.uoa.gr/~eusipco/},
  address={Rhodes, Greece},
  abstract={Recently, a new subspace smoothing algorithm for estimation of directions of arrival (DOA) in coherent signal environment by using antenna arrays was presented. Unlike the existing forward and backward spatial smoothing algorithm, the new subspace smoothing algorithm is not restricted to uniformly linear arrays, and M-1 DOA's of direct path and multipath components can be estimated, where M is the number of the sensors. Unfortunately, the steering vectors have to be estimated first for several time instances in that algorithm, which is computationally very intensive. In order to reduce the computational cost but keep the advantages of the subspace smoothing algorithm, a modified version of the subspace smoothing algorithm will be presented in this paper. We will show that there is equivalence between the modified subspace smoothing algorithm and the well-known forward spatial smoothing algorithm. We will also show that by using the modified subspace smoothing algorithm the array aperture is extended virtually. Finally, simulation results will demonstrate the features of our modified algorithm.},
  booktitle={European Signal Processing Conference (EUSIPCO 98)}