| Presentation | 2004-06-18 On selection of OVSF codes for MC-CDMA downlinks Takamichi INOUE, Deepshikha GARG, Fumiyuki ADACHI, |
|---|---|
| PDF Download Page |  PDF download Page Link |
| Abstract(in Japanese) | (See Japanese page) |
| Abstract(in English) | In MC-CDMA downlink, orthogonal variable spreading factor (OVSF) codes can be used to allow multirate communications while maintaining the orthogonality among the users with different data rates. In this paper, we point out that simple selection of the OVSF codes results in degraded performance. We show that this happens because simple code selection results in power concentration over certain consecutive subcarriers ; severe power loss in the received signal occurs when these subcarriers experience a deep fade in a frequency selective fading channel. In addition, we show two effective techniques to avoid the performance degradation : random code selection and frequency interleaving ; which technique provides a better performance depends on modulation levels, code multiplexing order, and presence of channel coding. |
| Keyword(in Japanese) | (See Japanese page) |
| Keyword(in English) | MC-CDMA / MMSE frequency-domain equalization / OVSF code / frequency-selective fading / frequency interleaving |
| Paper # | RCS2004-78 |
| Date of Issue |
| Conference Information | |
| Committee | RCS |
|---|---|
| Conference Date | 2004/6/11(1days) |
| Place (in Japanese) | (See Japanese page) |
| Place (in English) | |
| Topics (in Japanese) | (See Japanese page) |
| Topics (in English) | |
| Chair | |
| Vice Chair | |
| Secretary | |
| Assistant | |
| Paper Information | |
| Registration To | Radio Communication Systems (RCS) |
|---|---|
| Language | JPN |
| Title (in Japanese) | (See Japanese page) |
| Sub Title (in Japanese) | (See Japanese page) |
| Title (in English) | On selection of OVSF codes for MC-CDMA downlinks |
| Sub Title (in English) | |
| Keyword(1) | MC-CDMA |
| Keyword(2) | MMSE frequency-domain equalization |
| Keyword(3) | OVSF code |
| Keyword(4) | frequency-selective fading |
| Keyword(5) | frequency interleaving |
| 1st Author's Name | Takamichi INOUE |
| 1st Author's Affiliation | Dept. of Electrical and Communication Engineering, Graduate School of Engineering, Tohoku University() |
| 2nd Author's Name | Deepshikha GARG |
| 2nd Author's Affiliation | Dept. of Electrical and Communication Engineering, Graduate School of Engineering, Tohoku University |
| 3rd Author's Name | Fumiyuki ADACHI |
| 3rd Author's Affiliation | Dept. of Electrical and Communication Engineering, Graduate School of Engineering, Tohoku University |
| Date | 2004-06-18 |
| Paper # | RCS2004-78 |
| Volume (vol) | vol.104 |
| Number (no) | 123 |
| Page | pp.pp.- |
| #Pages | 6 |
| Date of Issue | |