We propose the transmission scheme to increase the maximum number of simultaneous users for embedded PPM-OCDMA systems without degrading the bit error rate(BER). In the conventional scheme, each PPM slot position and its transmitted symbol are embedded in the desired user's weighted positions to M-ary PPM-OCDMA, so the number of weights is equal to the number of PPM slots, and the number of codes is limitted to be small. In the proposed scheme, only the transmitted symbols are embedded in the desired user's weighted positions to M-ary PPM-OCDMA. So, the number of weights doesn't depend on the number of PPM slots. As the number of weights is decreased, the number of codes is increased compared to the conventional scheme under the condition that the bit rates are constant. We analyze the BER of the proposed scheme under the Poisson photon counting proccess. We show that the proposed scheme can increase the maximum number of simultaneous users compared to the conventional scheme under the conditions of achieving BER ≤ 10-9 and keeping the information rate constant.
|出版ステータス||Published - 2003 11月 7|
|イベント||2003 IEEE Pacific Rim Conference on Communications Computers and Signal Processing (PACRIM 2003) - Victoria, B.C., Canada|
継続期間: 2003 8月 28 → 2003 8月 30
|Other||2003 IEEE Pacific Rim Conference on Communications Computers and Signal Processing (PACRIM 2003)|
|Period||03/8/28 → 03/8/30|
ASJC Scopus subject areas
- コンピュータ ネットワークおよび通信