IAB Node MT Spatial Multiplexing via Flexible TDD Configuration
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Solution Overview
Problem
The integration of wireless access and backhaul links in IAB nodes faces challenges in implementing spatial multiplexing due to the half-duplex constraint, which prevents simultaneous downlink and uplink transmissions on the same time domain resource.
Innovation Solution
A communication method that involves obtaining transmission resource configurations with specific start and end time domain resources for uplink and downlink transmissions, and determining based on these configurations whether to perform uplink sending or downlink receiving on specific time domain resources, thereby aligning with the half-duplex constraint.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the MT of the IAB node uses a TDD-uplink-downlink common configuration that starts with a downlink time domain resource and ends with an uplink time domain resource, then the configuration structure is simplified, but spatial multiplexing of the access link and backhaul link cannot be implemented under the half-duplex constraint
Solution Approach 1:
The patent applies dynamics by making the time domain resource configuration flexible and adaptable. Instead of using a fixed TDD-uplink-downlink common configuration, the patent introduces a first configuration and a second configuration that can be dynamically selected or combined based on whether spatial multiplexing is required. This allows the system to switch between configuration modes to balance structural simplicity and spatial multiplexing capability.
Solution Approach 2:
The patent segments the time domain resources into two separate configurations: a first configuration for basic TDD operation and a second configuration for enabling spatial multiplexing. By dividing the resource allocation into distinct segments, the system can selectively apply the appropriate configuration for different operational scenarios, allowing MT to perform uplink sending on downlink time domain resources or downlink receiving on uplink time domain resources when spatial multiplexing is enabled.
2Device complexity
If the access link and backhaul link both use the same TDD-uplink-downlink common configuration, then resource allocation is simplified, but the half-duplex constraint prevents simultaneous transmission and reception
Solution Approach 1:
The patent applies local quality by allowing different time domain resources to have different transmission directions within the same configuration period. The first configuration establishes baseline resource allocation, while the second configuration locally modifies specific time domain resources to enable uplink or downlink transmission. This localized differentiation allows the system to maintain overall resource allocation simplicity while ensuring half-duplex constraint compliance through targeted resource direction assignments.
3Ease of operation
If the MT performs downlink receiving only on downlink time domain resources of the DU, then the configuration is straightforward, but resource utilization is reduced
Solution Approach 1:
The patent applies dimensionality change by introducing a second configuration dimension that operates alongside the first configuration. Instead of limiting MT to a single dimension of downlink receiving on downlink time domain resources, the second configuration adds another dimension that allows MT to perform uplink sending on downlink time domain resources or downlink receiving on uplink time domain resources. This dimensional expansion increases resource utilization while maintaining operational clarity through structured configuration management.
Data Source
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AI summary
This application provides a communication method and apparatus, to expect to better implement spatial multiplexing of an access link and a backhaul link of an IAB node. The method is applied to an MT of the IAB node. The method includes: obtaining transmission resource configurations, where the transmission resource configurations include a first configuration and a second configuration, the first configuration indicates that a start time domain resource is a downlink time domain resource and/or an end time domain resource is an uplink time domain resource in one configuration period, and the second configuration indicates that a start time domain resource is an uplink time domain resource and/or an end time domain resource is a downlink time domain resource in one configuration period; and determining, according to a specified rule, one or more of the following: whether to perform uplink sending on an uplink time domain resource in the transmission resource configurations, whether to perform downlink receiving on a downlink time domain resource in the transmission resource configurations, whether to send an uplink signal on a time domain resource in a reference configuration, or whether to receive a downlink signal on a time domain resource in the reference configuration, where the reference configuration is at least one of the first configuration and the second configuration.