D2D Discovery Message Format Identification via Reference Signals

The patent applies the principle of using different reference signal sequences (analogous to color changes) to indicate different discovery message formats. Each format (consumer, public safety, relay) is associated with a specific reference signal sequence, allowing receivers to identify the format through sequence detection before payload processing, thereby resolving the ambiguity caused by varying payload sizes and formats on the same carrier.

The patent implements preliminary action by having the transmitter indicate the discovery message format using reference signal sequences before the actual payload transmission. This allows the receiver to pre-configure the appropriate format-specific parameters and processing logic in advance, avoiding the need for complex runtime analysis of payload content to determine format, thereby reducing receiver complexity while maintaining multi-format support.

The patent introduces reference signal sequences as an intermediary element between the physical layer transmission and higher layer processing. These sequences serve as format indicators that mediate the communication between transmitter and receiver, enabling reliable format identification without requiring complex payload analysis. The intermediary reference signals provide a simple yet reliable mechanism for format differentiation, reducing false alarms while maintaining low processing complexity.