Dedicated Search Space Mapping for Initial Access Control Channels

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Solution Overview

Problem

In next-generation communications systems, user equipment with different bandwidths face challenges in determining their dedicated operating frequency domain resources during initial access due to common signaling used in conventional PBCH, which does not allow for individual bandwidth allocation.

Innovation Solution

A method involving sending a preamble signal sequence and receiving higher layer signaling to determine user equipment-dedicated search space, including frequency domain resource location information, allowing for differentiated search space locations and sizes based on bandwidth capabilities, and using continuous or discrete mapping to enhance control channel capacity and reduce collision probability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If common signaling (PBCH) is used to indicate control channel resources, then signaling simplicity is maintained, but user equipment cannot learn dedicated operating frequency domain resource information

Engineering Contradiction:

Improvesignaling simplicityVSAvoiddedicated operating frequency domain resource information

Core Design Contradiction:

Ease of operationVSLoss of information

Solution Approach 1:

The search space is segmented into common search space and user equipment-dedicated search space. The common search space uses common signaling for basic control, while the user equipment-dedicated search space carries user-specific frequency domain resource information through higher layer signaling (Message 2 or Message 4), resolving the information loss problem while maintaining signaling simplicity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Higher layer signaling (Message 2 or Message 4) acts as an intermediary between the common signaling and user equipment-specific resource allocation. This intermediary carries the dedicated operating frequency domain resource information that cannot be transmitted through common PBCH signaling alone.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Device complexity

If single search space location is used for all user equipment, then control channel structure is simplified, but control channel collision probability increases during initial access

Engineering Contradiction:

Improvecontrol channel structureVSAvoidcontrol channel collision probability

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The search space is divided into common search space and user equipment-dedicated search space with different time-frequency resource locations. This segmentation reduces control channel collision probability during initial access by allowing user equipment to be assigned dedicated search spaces, while the overall structure remains relatively simple through standardized mapping relationships.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The search space location and size are made dynamic and adaptable to different user equipment bandwidth capabilities. The network device determines appropriate search space locations and sizes based on user equipment bandwidth, enabling flexible resource allocation that reduces collisions without overly complicating the control channel structure.

Inventive Principle:

Principle #15Dynamics

3Ease of manufacture

If fixed control channel allocation is used, then implementation is simplified, but control channel capacity is insufficient for diverse bandwidth capabilities

Engineering Contradiction:

Improveimplementation simplicityVSAvoidcontrol channel capacity

Core Design Contradiction:

Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The control channel allocation is made dynamic and adaptable to different user equipment bandwidth capabilities. The network device determines appropriate search space locations and sizes based on user equipment bandwidth, enabling flexible resource allocation that increases control channel capacity while maintaining implementation simplicity through standardized mapping relationships.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The search space parameters (location and size) are changed according to user equipment bandwidth capabilities. Different search space configurations are applied based on the detected bandwidth, allowing the control channel to adapt to diverse user equipment requirements without fundamentally changing the implementation approach.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS12513696B2Control channel resource indication method, user equipment, and network device

Publication Date: 2025.12.30 HUAWEI TECH CO LTD

AI summary

Example control channel resource indication methods and apparatus are described. One example method includes receiving response information corresponding to a random access preamble, wherein the response information is scheduled by downlink control information carried in common search space and the response information comprises frequency domain resource information of user equipment-dedicated search space. A second frequency domain resource of the user equipment-dedicated search space is determined based on the frequency domain resource information.