Waveform Reuse in Contention-Free Random Access

Solution Overview

Problem

Current wireless communication systems face inefficiencies in contention-free random access (CFRA) procedures due to the use of different waveform types for initial and acknowledgement messages, leading to resource fragmentation and increased processing overhead.

Innovation Solution

The technique allows user equipment (UE) to reuse the same waveform type for both the initial CFRA message and the acknowledgement message, using a preconfigured time window for retransmission, which reduces resource utilization inefficiencies and processing overhead.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If different waveform types are used for initial CFRA message and acknowledgement message, then message differentiation is achieved, but resource fragmentation and processing overhead increase

Engineering Contradiction:

Improvemessage differentiationVSAvoidprocessing overhead

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the waveform types used for initial CFRA message and acknowledgement message into a single waveform type. This consolidation eliminates the need to switch between different waveform types, thereby reducing processing overhead and resource fragmentation while maintaining message differentiation through other means such as resource allocation or message structure

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent makes a single waveform type universal for multiple purposes - it can be used for both the initial CFRA message and the acknowledgement message. This multi-functionality approach eliminates the need for multiple specialized waveform types, reducing system complexity and processing requirements while maintaining the ability to distinguish between different message types through alternative mechanisms

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If different waveform types are used for initial CFRA message and acknowledgement message, then message differentiation is achieved, but resource utilization efficiency decreases

Engineering Contradiction:

Improvemessage differentiationVSAvoidresource utilization efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent merges the waveform types used for initial CFRA message and acknowledgement message into a single waveform type. This consolidation eliminates the need to switch between different waveform types, thereby reducing processing overhead and resource fragmentation while maintaining message differentiation through other means such as resource allocation or message structure

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent makes a single waveform type universal for multiple purposes - it can be used for both the initial CFRA message and the acknowledgement message. This multi-functionality approach eliminates the need for multiple specialized waveform types, reducing system complexity and processing requirements while maintaining the ability to distinguish between different message types through alternative mechanisms

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS20250097975A1Reusing waveform types for contention-free random access procedures

Publication Date: 2025.03.20 QUALCOMM INC

AI summary

Methods, systems, and devices for wireless communications are described. The described techniques may enable a user equipment (UE) to reuse a same waveform type for both of a first contention-free random access (CFRA) message and an acknowledgement (ACK) message for a random access response (RAR) message from a network entity. The UE may transmit the first CFRA message using a first waveform type and via a first resource with a first resource index, and may retransmit the first waveform type via a second resource with the first resource index in response to receiving the RAR message. In some examples, the UE may not receive the RAR message. In such examples, the UE may not retransmit the waveform. That is, if the network entity does not receive the response to the RAR message, the network entity may interpret the lack of response as a negative acknowledgement (NACK).