Impact of frequency-selective fading on distributed dynamic channel assignment in a DS-CDMA multi-hop virtual cellular network

Recently, we have proposed a DS-CDMA multi-hop virtual cellular network (VCN). The channel segregation dynamic channel allocation (CS-DCA) is applied for wireless multi-hop links in each virtual cell. If all wireless ports in a virtual cell have successfully allocated channels, the channel allocation is successful; otherwise the channel allocation is considered to have failed. In this paper, the failure rate is examined by computer simulation. It is shown that CS-DCA provides significantly smaller failure rate compared to fixed channel allocation (FCA). It is also found that the CS-DCA failure rate is sensitive to the frequency-selectivity of the channel. The CS-DCA failure rate becomes minimum at a certain number L of propagation paths. This suggests that the spreading bandwidth should be carefully chosen.