- タイトル
- A proposal of code allocation for orthogonal CSK slotted ALOHA systems
- 著者
- D.Umehara, K.Sugano, Y.Morihiro, M.Kawai
- 出典
- 信学技報WBS, no.WBS2004-3,
2004/06.
- キーワード
- slotted ALOHA, spread ALOHA, satellite communication, throughput, DS-CDMA, crosscorrelation, bit error rate
- 概要
- We pay attention to demand assignment S-CDMA (synchronous code division multiple access) as one of multiple access techniques for packet data satellite communication. We utilize orthogonal CSK (code shift keying) sequences, which are obtained by orthogonalization of CSK sequences, as spreading code sequences for S-CDMA. The orthogonal CSK sequences include many QS (quasi-synchronous) sequences which have zero cross correlation in a given range within access timing point at center. We propose a method to preferentially allocate one of sequences which preserve zero cross correlated with all already assigned sequences at widest range within access timing point at center. Further, we show that the S-CDMA with the proposed code allocation has high tolerance for access timing errors due to channel fluctuation.
- 分類
- [SST]直接拡散アロハ：スロット付ALOHA (No.4584)