Title :
Noncoherent LMS algorithm for noncoherent sequence estimation
Author :
Schober, Robert ; Gerstacker, Wolfgang H.
Author_Institution :
Lab. fur Nachrichtentech., Erlangen-Nurnberg Univ., Germany
Abstract :
A novel noncoherent adaptive algorithm for channel estimation is introduced. The proposed noncoherent least-mean-square (NC-LMS) algorithm can be combined easily with noncoherent sequence estimation (NSE) for M-ary differential phase-shift keying (MDPSK) signals transmitted over intersymbol interference (ISI) channels. For zero frequency offset the convergence speed and the steady-state error of the novel noncoherent adaptive algorithm are similar to those of a conventional (coherent) LMS algorithm. However, the conventional LMS algorithm diverges even for relatively small frequency offsets, whereas the proposed NC-LMS algorithm also converges for relatively large frequency offsets. Simulations confirm the good performance of NSE combined with noncoherent adaptive channel estimation in time-variant (fading) ISI channels
Keywords :
adaptive equalisers; adaptive estimation; cellular radio; convergence of numerical methods; differential phase shift keying; fading channels; intersymbol interference; least mean squares methods; parameter estimation; sequential estimation; time-varying channels; GSM; Global System for Mobile Communication; M-ary differential phase-shift keying; MDPSK signals; NC-LMS algorithm; channel estimation; convergence speed; equalization; intersymbol interference; noncoherent LMS algorithm; noncoherent adaptive algorithm; noncoherent adaptive channel estimation; noncoherent least-mean-square algorithm; noncoherent sequence estimation; simulations; steady-state error; time-variant fading ISI channels; zero frequency offset; Adaptive algorithm; Channel estimation; Convergence; Differential phase shift keying; Frequency; Intersymbol interference; Least squares approximation; Neutron spin echo; Phase estimation; Steady-state;
Conference_Titel :
Global Telecommunications Conference, 2000. GLOBECOM '00. IEEE
Conference_Location :
San Francisco, CA
Print_ISBN :
0-7803-6451-1
DOI :
10.1109/GLOCOM.2000.891293
