This paper presents an efficient dynamic spectrum allocation （DSA） scheme in a flexible spectrum licensing environment where multiple networks coexist and interfere with each other. In particular, an extension of vi...This paper presents an efficient dynamic spectrum allocation （DSA） scheme in a flexible spectrum licensing environment where multiple networks coexist and interfere with each other. In particular, an extension of virtual boundary concept in DSA is proposed, which is spectrally efficient than the previous virtual boundary concept applied to donor systems only. Here, the same technique is applied to both donor and rental systems so as to further reduce the occurrences where the insertion of guard bands is obligatory and as a result provides better spectral efficiency. The proposed extension improves the spectrum utilization without any compromise on interference and fairness issues.展开更多
A new construction method of two-dimensional （2D） variable-weight optical orthogonal codes （VWOOCs） is proposed for high-speed optical code-division multiple-access （OCDMA） networks supporting multiple qualities...A new construction method of two-dimensional （2D） variable-weight optical orthogonal codes （VWOOCs） is proposed for high-speed optical code-division multiple-access （OCDMA） networks supporting multiple qualities of services （QoS）. The proposed codes have at most one-pulse per wavelength （AM-OPPW） property. An upper bound of the codeword cardinality of the 2D VWOOCs with AM-OPPW property is derived. It is then shown that the constructed codes have ideal correlation properties and optimal cardinality. Moreover, the code length and the bit-error-rate （BER） performance of the proposed codes are compared with those of the codes proposed previously.展开更多
基金This work was supported in part by the National Nature Science Foundation of China (NSFC) under Grant No. 90604035the 863 high-tech R&D program of China under Grant No. 2005AA123950.
文摘This paper presents an efficient dynamic spectrum allocation （DSA） scheme in a flexible spectrum licensing environment where multiple networks coexist and interfere with each other. In particular, an extension of virtual boundary concept in DSA is proposed, which is spectrally efficient than the previous virtual boundary concept applied to donor systems only. Here, the same technique is applied to both donor and rental systems so as to further reduce the occurrences where the insertion of guard bands is obligatory and as a result provides better spectral efficiency. The proposed extension improves the spectrum utilization without any compromise on interference and fairness issues.
基金supported by the National Natural Science Foundation of China (No. 60772087)the "111"Project of China (No.111-2-14)the Research Project of Guanxi Department of Education (No. 200911LX257)
文摘A new construction method of two-dimensional （2D） variable-weight optical orthogonal codes （VWOOCs） is proposed for high-speed optical code-division multiple-access （OCDMA） networks supporting multiple qualities of services （QoS）. The proposed codes have at most one-pulse per wavelength （AM-OPPW） property. An upper bound of the codeword cardinality of the 2D VWOOCs with AM-OPPW property is derived. It is then shown that the constructed codes have ideal correlation properties and optimal cardinality. Moreover, the code length and the bit-error-rate （BER） performance of the proposed codes are compared with those of the codes proposed previously.
