Preamble Sequence Prefix Suffix Multipath Interference Cancellation

The patent applies preliminary action by adding a prefix sequence before the main frequency offset estimation sequence. This prefix sequence is specifically designed to cancel multipath interference in advance, so that when the main sequence is processed for frequency offset estimation, the multipath interference has already been mitigated. This resolves the contradiction by preparing the signal structure beforehand to improve estimation accuracy without complicating the actual estimation operation.

The patent segments the frequency offset estimation sequence into multiple identical subsequences arranged in parallel. By dividing the estimation process into multiple segments that can be processed independently and then combined, the patent simplifies the overall operation while improving robustness against multipath interference. Each subsequence can be processed separately, and their combined result provides more accurate frequency offset estimation.

The prefix sequence is designed in advance to counteract multipath interference effects. By performing this preliminary anti-multipath action, the patent achieves accurate frequency offset estimation without requiring complex processing during the main estimation phase. The prefix sequence structure is predetermined and can be generated using simple algorithms, maintaining ease of implementation while dramatically improving estimation accuracy.

The patent converts the harmful multipath interference into a beneficial structure by designing the prefix sequence to exploit the known characteristics of multipath channels. Instead of trying to eliminate multipath effects through complex filtering, the patent uses the prefix to create a structured signal that, when processed, automatically cancels multipath interference. This transforms the harmful interference into a feature that aids accurate estimation.

By segmenting the frequency offset estimation sequence into multiple identical subsequences, the patent enables the system to handle larger frequency offset ranges. Each subsequence can be processed independently with the same simple algorithm, and the results are combined to achieve accurate estimation across a wide range. This segmentation approach maintains algorithmic simplicity while expanding adaptability.

The patent creates a universal estimation structure where the same processing algorithm can be applied to each subsequence regardless of the channel conditions or frequency offset magnitude. This multi-functional approach allows the system to adapt to different channel conditions and estimation ranges without requiring multiple different algorithms, thus maintaining simplicity while achieving versatility.