IEEE 802.11b Complementary Code Keying and Complementary Signals Derived from Biorthogonal Sequences

Two classes of complementary signal sets are compared in terms of their complementary properties and their error probabilities for channels with thermal noise and multipath interference. One class consists of the high-rate (11 Mbps and 5.5 Mbps) signals employed in the IEEE 802.11b standard, and the other class includes full-rate (11 Mbps) complex signals derived from biorthogonal sequences and half-rate (5.5 Mbps) biorthogonal signals. We examine several types of complementary properties of each class of signals and give performance comparisons for the signals when employed on channels in which thermal noise is the only disturbance and channels with thermal noise and multipath interference. For standard IEEE 802.11b complementary-code-key (CCK) modulation, we find the performance is strongly dependent on the differential multipath delay. For systems that employ binary error-control coding, the signals that are based on biorthogonal modulation are superior to the two IEEE 802.11b CCK signal sets.