DMRS-less PUCCH Sequence Transmission for Low SNR Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems face challenges in efficiently transmitting physical uplink control channels (PUCCH) without demodulation reference signals (DMRS), particularly at low signal-to-noise ratios, leading to performance degradation at cell edges due to channel estimation issues.
Innovation Solution
The method involves generating a PUCCH sequence based on payload size and transmitting multiple repetitions of this sequence, using orthogonal or non-orthogonal sequences to optimize communication, thereby avoiding channel estimation problems and improving bit error rate performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If DMRS-based coherent PUCCH transmission is used, then channel estimation accuracy is improved, but performance degrades at low signal-to-noise ratios and cell edges due to estimation errors
Solution Approach 1:
The patent removes the DMRS (demodulation reference signal) from the PUCCH transmission structure. By extracting this component, the system eliminates channel estimation operations that fail at low SNR and cell edges, thereby resolving the contradiction between estimation accuracy and transmission reliability in challenging radio conditions
Solution Approach 2:
The patent replaces the coherent detection mechanism (which relies on channel estimation) with non-coherent detection. This substitution eliminates the need for accurate channel estimates by using sequence-based transmission where detection relies on correlation properties rather than channel state information, enabling reliable operation at low SNR
2Reliability
If sequence-based noncoherent PUCCH transmission is used, then performance at low signal-to-noise ratios is improved, but channel estimation issues persist without repetition
Solution Approach 1:
The patent divides the PUCCH transmission into multiple repetitions of the same sequence. This segmentation approach allows the receiver to accumulate energy across repetitions through non-coherent combining, improving detection reliability without requiring channel estimation, thereby resolving the contradiction between reliability and estimation capability
Solution Approach 2:
The patent employs repeated transmission of the PUCCH sequence multiple times in sequence. This continuous repetition enables the receiver to perform non-coherent accumulation across time, maintaining useful action (signal energy) continuously and improving detection reliability without requiring intermittent channel estimation operations
3Reliability
If multiple PUCCH repetitions are transmitted, then bit error rate performance is improved, but transmission time and resource consumption increase
Solution Approach 1:
The patent transmits the PUCCH sequence in periodic repetitions rather than continuously. This periodic action allows the receiver to accumulate energy at regular intervals, improving bit error rate performance through non-coherent combining while limiting total transmission time to a manageable duration, thus resolving the contradiction between reliability improvement and time consumption
Data Source
AI summary
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may generate a physical uplink control channel (PUCCH) sequence for a set of PUCCH repetitions, wherein the PUCCH sequence is based at least in part on a PUCCH payload size. The UE may transmit the set of PUCCH repetitions using the PUCCH sequence. Numerous other aspects are provided.