Sphere Constrained Block RSSE With Per-Survivor Intra-Block Processing for CCK Transmission

In the Wireless Local Area Network (WLAN) standard IEEE 802.11b, Complementary Code Keying (CCK) modulation has been adopted for the high data rate transmission mode, which can be considered as a special type of spread spectrum modulation with data-dependent spreading. In this paper, complexity reduction for block Reduced-State Sequence Estimation (bRSSE), tailored for CCK transmission over frequency-selective channels, is considered. A trellis diagram for the chip phases of the codewords fully describes the CCK code properties. Subset trellises are derived from the full CCK trellis diagram based on set partitioning of the multidimensional CCK code set. The CCK subset trellises connect consecutive bRSSE states in order to form a compound trellis.