We propose several classes of fractional lower order moment (FLOM)-based ma
trices that can be used with MUSIC to estimate the DOAs of independent circ
ular signals embedded in additive S alphaS noise (e.g., sea clutter). We ra
n simulations with different choices of FLOM parameter p for our FLOM-based
matrices and conclude that when the noise is S alphaS with unknown alpha n
ot equal 2, FLOM-multiple signal clasification (MUSIC) with p close to unit
y yields good performance. The performance of FLOM-MUSIC and robust covaria
tion-based (ROC)-MUSIC are similar. Three scenarios that contain circular s
ignals [phase modulation (PM), circularly symmetrical Gaussian, and quatern
ary phase-shift keying (QPSK)] and one scenario that contains noncircular s
ignals [binary phase-shift keying (BPSK)I, all embedded in the same S alpha
S noise, are tested, These simulation results reveal that the scenario cont
aining BPSK signals leads to poor performance, indicating that FLOM-MUSIC i
s presently limited to circular signals.