這篇論文中，我們提出了分散式中繼網路系統架構(Distributed-node Network)。此系統應用區塊展頻(Block Spreading)技術做編碼。區塊展頻(Block Spreading)並非新的概念，但用於分散式中繼網路系統中，可解決高速傳輸下使用者間的干擾。因為在高速傳輸下，對同一封包其連續的區塊時間間隔小於無線通道的同調時間(coherence time)，因此較容易確保碼的正交性。這樣的區塊展頻比傳統的DS-CDMA更具優勢，且改善了傳統MC-CDMA中的多重擷取干擾(MAI)的問題。將此區塊展頻技術應用於分散式中繼網路中，結合節點可有中繼站(relay)的特性，電壓和接收(voltage-sum reception)比傳統功率和接收(power-sum reception)獲得更大的能量，可改善功率利用效率。隨著網路層的節點數增加，此效應會更明顯，使訊
雜比提升。

Considering rapid progress in the processing capability of RFID-chips, it is interesting to fabricate a communications space composed of a large amount of distributed-nodes which have relay functions as well as transmit and receive functions. Block spreading (BS) is not the new concept to be proposed in the thesis, however it is used on the distributed-node network dealing with multi-user interference for high speed transmission. The code orthogonality of BS is easily maintained because the consecutive block duration within a packet for high speed transmission is smaller than the coherence time of the wireless channel. This analysis concludes the superiority of the BS over the spreading in the conventional DS-CDMA system and the frequency domain spreading in the conventional MC-CDMA system in MAI removal. By using the distributed-node network, voltage-sum reception is applied through pilot response making non-rotated route-signals. As a large value of node number Nv, the more power voltage-sum surpass over power-sum. This provide an improvement of power utility. As more node number Nv, more remarkable the effect will has, having higher SNR ratio value.

Bibliography
[1] M. Tomita, N. Kuroyanagi, K. Ohtake, S. Ozawa and N. Suehiro, "Performance of Block Spreading MIMO-CDMA Systems for Heavy Multi-path Environment," Wireless Networks, Communications and Mobile Computing, 2005 International Conference on , vol. 1, pp. 113-118, 2005.
[2] M. Tomita, N. Kuroyanagi, K. Ohtake, N. Suehiro and S. Matsufuji, "A multirate CDMA system with block-spreading schemes for anti-interference and high frequency e ciency," Proceedings of the 2006 international conference on Wireless communications and mobile computing , pp. 845-850, July 3-6 2006.
[3] X. Peng, A. S. Madhukumar, F. Chin and T.T. Tjhung, "Block spreading CDMA system: a simpli ed scheme using despreading before equalisation for broadband uplink transmission," Communications, IET , vol. 3, no. 4, pp. 666-676, 2009.
[4] M. Tomita, N. Kuroyanagi, K. Ohtake, N. Suehiro and S. Matsufuji, "Capacity Comparison on CDMA Systems for High Data Rate Transmission," IEIC Technical Report (Institute of Electronics, Information and Communication Engineers), vol. 105, no. 365, pp. 7-12, 2005.
[5] H. Inokura, K. Otake, N. Kuroyanagi, M. Tomita, S. Ozawa, and N. Suehiro, "A CDMA-MIMO system with multiple dimension-decorrelating-detectors ," International Conference on Communications, Vehicular Technology Conference, 2003. VTC 2003-Fall. 2003 IEEE 58th , vol. 2, pp. 1364-1368 , 2003.
[6] Cha'o-Ming Chang and Kwang-Cheng Chen, "Frequency domain approach to multiuser detection in DS-CDMA communications ," Communications Letters, IEEE , vol. 4, no. 11, pp. 331-333, 2000.