Abstract
Suppression of multiuser interference (MUI) and mitigation of multipath effects constitute major challenges in the design of third-generation wireless mobile systems. Most wide-band and multicarrier uplink code-division multiple-access (CDMA) schemes suppress MUI statistically in the presence of unknown multipath. For fading resistance, they all rely on transmit- or receive-diversity and multichannel equalization based on bandwidth-consuming training sequences or self-recovering techniques at the receiver end. Either way, they impose restrictive and difficult to check conditions on the finite-impulse response channel nulls. Relying on block-symbol spreading, we design a mutually-orthogonal usercode-receiver (AMOUR) system for quasi-synchronous blind CDMA that eliminates MUI deterministically and mitigates fading regardless of the unknown multipath and the adopted signal constellation. AMOUR converts a multiuser CDMA system into parallel single-user systems regardless of multipath and guarantees identifiability of users' symbols without restrictive conditions on channel nulls in both blind and nonblind setups. An alternative AMOUR design called Vandermonde-Lagrange AMOUR is derived to add flexibility in the code assignment procedure. Analytic evaluation and preliminary simulations reveal the generality, flexibility, and superior performance of AMOUR over competing alternatives.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2064-2076 |
| Number of pages | 13 |
| Journal | IEEE Transactions on Communications |
| Volume | 48 |
| Issue number | 12 |
| DOIs | |
| State | Published - Dec 2000 |
Bibliographical note
Funding Information:Paper approved by M. Brandt-Pearce, the Editor for Modulation and Signal Design of the IEEE Communications Society. Manuscript received February 17, 1999; revised December 30, 1999 and March 29, 2000. This work was supported by the National Science Foundation under CCR Grant 98-05350 and by the Army Research Laboratory under Grant DAAL01-98-Q-0648. This paper was presented in part at the International Conference on ASSP, Phoenix, AZ, March 1999, and in part at GLOBECOM, Rio de Janeiro, Brazil, December 1999.