Cross-Carrier SRS Triggering for Multi-TRP Coherent Joint Transmission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication standards, such as NR Release-17, face limitations in efficiently supporting Multi-TRP Coherent Joint Transmission (CJT) operations due to constraints in SRS triggering and resource allocation, leading to increased overhead and latency in multi-component carrier scenarios.
Innovation Solution
Implementing flexible cross-carrier aperiodic SRS (AP-SRS) triggering, semi-persistent (SP-SRS) activation, and enhanced SRS resource configuration to allow simultaneous triggering and transmission across multiple component carriers, reducing overhead and latency through improved DCI and MAC CE mechanisms.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing NR Release-17 standards are used for SRS triggering and resource allocation, then basic Multi-TRP CJT operation is supported, but overhead and latency increase in multi-component carrier scenarios
Solution Approach 1:
The patent segments the SRS resource allocation by introducing separate SRS resource sets for different component carriers, with each resource set independently configured and triggered. This allows parallel SRS transmissions across multiple carriers, reducing the time required for channel state information feedback in multi-component carrier Multi-TRP CJT operations.
Solution Approach 2:
The patent extends SRS resource allocation into the carrier dimension by enabling simultaneous SRS transmissions across multiple component carriers. This multi-dimensional approach transforms the single-carrier sequential process into a multi-carrier parallel process, significantly reducing latency while maintaining reliability.
2Reliability
If existing NR Release-17 standards are used for SRS triggering and resource allocation, then basic Multi-TRP CJT operation is supported, but overhead increases in multi-component carrier scenarios
Solution Approach 1:
The patent creates universal SRS resource configurations that can be applied across multiple component carriers. By defining common parameters and structures that work across carriers, the system reduces redundant signaling and configuration overhead while maintaining the reliability needed for Multi-TRP CJT operations.
Solution Approach 2:
The patent optimizes SRS resource allocation parameters specifically for multi-component carrier scenarios, adjusting periodicity, bandwidth, and resource mapping to minimize overhead. These parameter changes enable efficient resource utilization across multiple carriers without excessive signaling burden.
3Loss of time
If flexible cross-carrier aperiodic SRS triggering is implemented, then overhead and latency are reduced, but system complexity increases
Solution Approach 1:
The patent uses MAC CE to pre-configure SRS resource sets and associate them with component carriers before actual SRS transmissions. This preliminary configuration stored in UE memory allows subsequent aperiodic triggering via DCI to operate with minimal processing complexity, as the resource allocation logic has already been prepared in advance.
4Productivity
If simultaneous SRS transmission across multiple component carriers is enabled, then latency is reduced, but resource allocation complexity increases
Solution Approach 1:
The patent segments SRS resources into distinct resource sets, each associated with specific component carriers. This segmentation allows the UE to independently manage and transmit SRS on different carriers according to pre-configured resource allocations, achieving parallel feedback efficiency while maintaining manageable resource allocation complexity through structured organization.
Data Source
AI summary
In cellular wireless communications, sounding reference signals (SRS) may be used to estimate uplink channel quality. A wireless communication device or mobile device (i.e., UE) can transmit an SRS to a base station (e.g., eNB for LTE and gNB for NR). SRS gives information about the combined effect of multipath fading, scattering, Doppler and power loss of transmitted signal. A number of enhancements may be introduced to the SRS for Multi-TRP Coherent Joint transmission.