Adaptive Orthogonal Cover Codes for mmWave Reference Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing reference signal designs in wireless communication systems, particularly in mmWave communication systems, fail to adapt to the increased subcarrier spacing (SCS) that can result in resource element failures, leading to inefficiencies in channel estimation and demodulation.
Innovation Solution
Adaptive configuration of resource elements to carry reference signals based on channel coherence parameters and user equipment preferences, using orthogonal cover codes (OCCs) that can be semi-statically or dynamically applied to ensure reliable communication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing reference signal designs are used in mmWave communication systems, then system simplicity is maintained, but resource element failures occur due to increased subcarrier spacing, leading to poor reliability
Solution Approach 1:
The patent applies dynamics by making the reference signal configuration adaptive rather than fixed. The base station dynamically determines the configuration of resource elements carrying reference signals based on channel coherence parameters (coherence bandwidth and coherence time) and UE preferences. This dynamic adaptation allows the system to adjust to increased subcarrier spacing in mmWave systems, preventing resource element failures and improving reliability without sacrificing simplicity.
2Reliability
If adaptive configuration of resource elements is implemented, then reliability is improved, but system complexity increases
Solution Approach 1:
The patent implements feedback by having the UE report channel coherence parameters (coherence bandwidth and coherence time) and preferences for CSI-RS or DMRS to the base station. The base station uses this feedback information to determine the optimal configuration of resource elements and orthogonal cover codes. This feedback mechanism enables adaptive configuration that improves reliability while keeping complexity manageable through intelligent decision-making based on reported parameters.
Solution Approach 2:
The patent applies parameter changes by adjusting the configuration of resource elements and orthogonal cover codes based on channel coherence parameters. Specifically, the base station determines whether to apply frequency domain OCCs, time domain OCCs, or both, depending on the coherence bandwidth and coherence time values. This parameter-based adaptation allows the system to optimize reference signal transmission without requiring complex structural changes.
3Measurement precision
If orthogonal cover codes are applied to more resource elements, then channel estimation accuracy is improved, but resource overhead increases
Solution Approach 1:
The patent applies local quality by selectively applying orthogonal cover codes to specific subsets of resource elements rather than uniformly to all resource elements. The base station determines which resource elements require OCC application based on channel coherence parameters and UE preferences. This selective approach improves channel estimation accuracy where needed while minimizing resource overhead by avoiding unnecessary OCC application on resource elements where it is not beneficial.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Some aspects of this disclosure relate to apparatuses and methods for implementing designs for configurations of resource elements to carry reference signals for a user equipment (UE). A reference signal can be processed by the UE according to the configuration of resource elements to carry reference signals. The configurations can be determined by the base station, and received from the base station by the UE. The base station determines the configurations based on information or parameters provided by the UE, e.g., a coherence bandwidth of the channel, a coherence time of the channel, a preference associated with channel status information reference signal, or a preference associated with demodulation reference signal for the UE.