Multistage multiuser detection for FHMA

A multistage multiuser detector (MMD) is presented for frequency-hopping/code-division multiple access (FH/CDMA.) The MMD reduces the bit-error rate (BER) over the conventional detector by exploiting prior knowledge of the addresses and energies of the user signals. This detector is a conservative multiuser detector which is robust to unknown users and has a complexity that is only linear in the number of users. The performance analysis of the synchronous MMD includes both theoretical and simulation BERs for the noiseless case as well as simulation results that include the presence of noise. The MMD is then extended to the fully asynchronous case which makes this work the first to propose an FH/CDMA multiuser detector for asynchronous communications. This asynchronous MMD is compared via simulation to the conventional detector