Receiver Phase Slip Compensation Using Pilot-Aided Decoding
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Solution Overview
Problem
Existing communication systems face performance deterioration due to phase errors caused by phase slips, especially when synchronization is lost, leading to increased bit error rates and difficulties in error correction, particularly in optical communication systems using differential modulation.
Innovation Solution
A communication method and system that employs decision iterative decoding for error correction codes, estimating and correcting phase differences using pilot symbols, allowing for iterative decoding and phase error correction, thereby maintaining performance akin to synchronous detection even during phase slips.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If differential modulation is used to reduce phase fluctuation influence, then stability against phase noise is improved, but demodulation performance deteriorates by approximately 3 dB compared to synchronous detection
Solution Approach 1:
The patent introduces a phase compensation unit as an intermediary component that processes the received signal before differential detection. This unit estimates and compensates for phase fluctuations using pilot symbols and feedback mechanisms, thereby maintaining the stability benefits of differential modulation while recovering demodulation performance that would otherwise be degraded by 3 dB
Solution Approach 2:
The patent implements a feedback mechanism where the receiver estimates phase fluctuations from received pilot symbols and feeds this information back to compensate for phase errors in subsequent symbols. This feedback loop enables the system to maintain stability against phase noise while achieving demodulation performance close to synchronous detection
2Measurement precision
If synchronous detection is used to achieve better demodulation performance, then measurement precision is improved, but phase slip causes performance deterioration and increased bit error rates
Solution Approach 1:
The patent applies preliminary phase compensation using pilot symbols before the actual data detection process. By estimating and correcting phase fluctuations in advance using known pilot sequences, the system prepares the signal for synchronous detection, thereby maintaining both high demodulation performance and reliability even when phase slips occur during transmission
3Reliability
If phase compensation is applied to maintain synchronization, then reliability is improved, but device complexity increases due to additional processing requirements
Solution Approach 1:
The patent applies phase compensation selectively using pilot symbols at specific intervals rather than continuously processing every symbol. This partial action approach maintains synchronization reliability while reducing the overall processing complexity and computational burden compared to continuous phase compensation methods
Data Source
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AI summary
A receiver, a transmitter, and a communication method, which exhibit performance close to that of synchronous detection even when a phase slip occurs, are obtained. Provided are a transmitter (10) for transmitting a transmission signal subjected to modulation after error correction coding and a receiver (20) including a phase compensation unit (21, 22) for receiving the transmission signal and performing demodulation therefor while maintaining synchronization thereof and an error correction decoding unit (23 to 25) for performing decoding processing for received data that has been subjected to the demodulation. The transmitter transmits a signal formed of a plurality of pilot sequences as a part of the transmission signal, and the receiver has a phase slip estimation processing function for estimating the phase slip by the phase compensation unit by using the plurality of pilot sequences, and for estimating a phase difference component by the error correction decoding unit, to thereby correct a phase of the received data.