E-DCH Frame Sequence Number Carrier Identification

The patent segments the FSN space by introducing a carrier indicator field that divides carriers into groups (intra-cell and inter-cell). This allows separate FSN counting for each carrier group, enabling the SRNC to identify which carrier a data stream belongs to while maintaining a relatively simple frame structure. The segmentation resolves the contradiction by organizing carriers into distinct segments with dedicated FSN ranges.

The patent adds another dimension to the FSN identification system by introducing the carrier indicator field as an additional parameter. Instead of relying solely on FSN values, the system now uses a two-dimensional identification approach: carrier indicator + FSN. This dimensional expansion allows unique identification of data streams from multiple carriers without significantly increasing overall frame complexity.

The patent applies local quality by making the carrier indicator field optional rather than universal. The frame structure adapts locally based on whether single-carrier or multi-carrier transmission is being used. When only one carrier is involved, the indicator field is omitted, keeping the structure simple. When multiple carriers are used, the indicator field is added only where needed, resolving the contradiction between reliability and complexity.

The patent introduces dynamic elements to the frame structure, allowing the presence and configuration of the carrier indicator field to change based on transmission requirements. The frame format can dynamically adapt between different versions (with or without carrier indicator), enabling the system to maintain simplicity when possible while providing enhanced functionality when needed for multi-carrier operations.

The patent applies preliminary action by pre-defining the FSN counting rules and carrier indicator mappings at the node B before actual data transmission. The modulo 2^X counting mechanism is established in advance, allowing the node B to systematically assign FSN values without complex real-time calculations. This preliminary setup reduces processing complexity during actual operation while maintaining high frame loss detection accuracy.

The patent implements feedback mechanisms where the node B tracks FSN values for each carrier and provides this information to the SRNC. The modulo counting creates a predictable pattern that enables the SRNC to detect frame loss by monitoring FSN sequence continuity. This feedback loop allows accurate frame loss detection while keeping node B processing manageable through systematic rather than ad-hoc FSN management.