USB 3.2 LFSR Descrambler Seed Locking for Faster Decoding

The patent applies preliminary action by extracting and validating the seed value during the link training phase before actual data transmission begins. The test and measurement instrument captures the LFSR state during training sequences (such as ULPI training or USB 3.2 Gen 2 training) and computes the seed value in advance, so that when data decoding starts, the seed is already determined and can be used immediately without time-consuming search algorithms.

The patent uses feedback by continuously monitoring the LFSR state during link training and using this feedback to dynamically extract and validate the seed value. The instrument compares the extracted seed with expected values or validates it through subsequent training sequences to ensure correctness, creating a closed-loop feedback mechanism that ensures accurate seed determination without brute-force search.

The patent applies the extraction principle by isolating and extracting the seed value from the LFSR state during link training. The test and measurement instrument captures the LFSR register state at specific points during training sequences and computes the seed value directly from this extracted state, eliminating the need for complex search algorithms or additional probing channels that would otherwise be required to determine the seed.

The patent implements self-service by enabling the link training process itself to provide the necessary information for seed extraction. The training sequences and LFSR state transitions during normal USB initialization serve the dual purpose of both link training and seed determination, allowing the system to self-produce the seed value without requiring external search algorithms or additional measurement channels.