Abstract
A new bandwidth-efficient asynchronous multicarrier DS CDMA scheme is proposed for the uplink. In this new scheme, each user employs a set of FIR filters whose impulse responses are a mutually orthogonal (MO) complementary set of sequences. The intentional inter-symbol interference (ISI) and multiple access interference (MAI) are eliminated by the properties of these sequences. We also propose applying this new scheme in a DS CDMA packet network in which slotted ALOHA or pure ALOHA protocol is used. Packet throughput figures are obtained for the new ALOHA/bandwidth-efficient asynchronous MC DS CDMA packet network. Numerical results are given for both slotted and pure ALOHA cases. With the same bandwidth and number of simultaneous users, the throughput is compared favorably to similar figures for single-carrier DS CDMA with random spreading sequences.
| Original language | English |
|---|---|
| Pages (from-to) | 1265-1273 |
| Number of pages | 9 |
| Journal | IEICE Transactions on Communications |
| Volume | E86-B |
| Issue number | 4 |
| State | Published - 04 2003 |
| Externally published | Yes |
Keywords
- ALOHA
- CDMA
- Multicarrier modulation
- Throughput