A multicarrier interleave-division uwb system

We propose a multicarrier interleave-division multiple-access scheme for ultra-wideband wireless communications. For the uplink, a chip-level interleaving method at the transmitter with a simple turbo receiver is proposed to effectively suppress the frequency-selective fading and multiple-access interference. Both hard and soft frequency notching methods are suggested to suppress the narrowband interference. For the downlink, a two-layer interleaving scheme is proposed, in which data from different users are separated in the frequency-domain while the different data streams for the same user are separated in the interleaver-domain. A joint power and subcarrier allocation algorithm is developed to exploit the multiuser diversity and thereby improve the system performance. The performance of the proposed system is evaluated by both theoretic analysis and simulations. It is seen that within a few iterations, the proposed system exhibits single-user performance even under over-loaded conditions