Receiver Synchronization via Modulated Scattered Pilots
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Solution Overview
Problem
Current DVB-T systems face challenges in performing fine synchronization in the time domain without continuous pilots, leading to increased receiver complexity and inefficiency, especially in multi-FFT size specifications.
Innovation Solution
The method involves using a modulated scattered pilot sequence, specifically a Gold sequence with good autocorrelation properties, to enable both coarse and fine synchronization in the time domain, reducing the need for continuous pilots and simplifying receiver design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If continuous pilots are used for fine synchronization in time domain, then synchronization accuracy is improved, but receiver complexity increases
Solution Approach 1:
The patent extracts the synchronization function from continuous pilots and implements it using scattered pilots instead. By removing the requirement for continuous pilots and using only scattered pilots with modified correlation processing, the receiver complexity is reduced while maintaining synchronization accuracy.
Solution Approach 2:
The patent changes the correlation processing parameters by using a modified correlation function that operates on scattered pilots. The correlation function is adjusted to account for the scattered nature of the pilots, enabling fine frequency offset estimation without requiring continuous pilot signals.
2Speed
If all synchronization steps are performed in time domain, then signal acquisition speed is improved, but fine frequency offset estimation capability deteriorates
Solution Approach 1:
The patent introduces a modified correlation function as an intermediary processing step that enables fine frequency offset estimation to be performed in the time domain. This intermediary function bridges the gap between time domain processing and frequency offset estimation, allowing both speed and precision requirements to be met without transitioning to frequency domain.
3Device complexity
If scattered pilots are used instead of continuous pilots for phase error correction, then receiver complexity is reduced, but synchronization performance deteriorates
Solution Approach 1:
The patent applies preliminary action by pre-processing the scattered pilot signals through a modified correlation function that compensates for their scattered nature. This preliminary processing prepares the signals in advance, enabling effective phase error correction and frequency offset estimation despite the reduced pilot density, thereby maintaining synchronization performance.
Data Source
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AI summary
Provided is a method for synchronizing a multiple carrier receiver to receive a transmitted signal. The method includes determining a location of one or more scattered pilot earners in a received symbol sequence and modulating the scattered pilot carriers in accordance with a single pseudorandom binary sequence. The method also includes performing phase error correction via the modulated scattered pilot carriers.