Serving Node Selection in Heterogeneous Networks

Solution Overview

Problem

In heterogeneous networks (HetNets), the load imbalance between macro NodeBs and micro NodeBs results in low system capacity due to the macro NodeB's higher transmit power dominating the selection process, leading to unequal coverage areas and inefficient resource allocation.

Innovation Solution

A method and system for selecting serving nodes that involve obtaining reference signal received parameters, such as RSRP or RSRQ, to separately select downlink and uplink serving nodes, allowing for a binding relationship to be established between them, thereby balancing load and improving system capacity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the UE selects a NodeB for access based on RSRP of the NodeB, then the signal quality is improved, but the load balance between macro NodeB and micro NodeB deteriorates

Engineering Contradiction:

Improvesignal qualityVSAvoidsystem capacity

Core Design Contradiction:

Measurement precisionVSProductivity

Solution Approach 1:

The patent segments the serving node selection into two independent parts: downlink serving node selection based on RSRP and uplink serving node selection based on path loss. This segmentation allows each link to be optimized separately, resolving the contradiction between signal quality and load balance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent applies different selection criteria to different links: the downlink uses RSRP-based selection for signal quality optimization, while the uplink uses path loss-based selection for load balance optimization. Each link receives localized optimization tailored to its specific requirements.

Inventive Principle:

Principle #3Local quality

2Area of stationary object

If the macro NodeB has higher transmit power, then the coverage area is improved, but the load balance between macro NodeB and micro NodeB deteriorates

Engineering Contradiction:

Improvecoverage areaVSAvoidsystem capacity

Core Design Contradiction:

Area of stationary objectVSProductivity

Solution Approach 1:

The patent segments the serving node selection into two independent parts: downlink serving node selection based on RSRP and uplink serving node selection based on path loss. This segmentation allows each link to be optimized separately, resolving the contradiction between signal quality and load balance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent applies different selection criteria to different links: the downlink uses RSRP-based selection for signal quality optimization, while the uplink uses path loss-based selection for load balance optimization. Each link receives localized optimization tailored to its specific requirements.

Inventive Principle:

Principle #3Local quality

3Device complexity

If the UE uses the selected NodeB as both uplink and downlink serving node, then the device complexity is reduced, but the load balance between macro NodeB and micro NodeB deteriorates

Engineering Contradiction:

Improveserving node configurationVSAvoidsystem capacity

Core Design Contradiction:

Device complexityVSProductivity

Solution Approach 1:

The patent segments the serving node selection into two independent parts: downlink serving node selection based on RSRP and uplink serving node selection based on path loss. This segmentation allows each link to be optimized separately, resolving the contradiction between signal quality and load balance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces dynamic serving node selection where the uplink and downlink serving nodes can be different. The UE dynamically determines which node to use for uplink and which for downlink based on path loss and RSRP measurements, allowing flexible adaptation to achieve load balance.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS9215651B2Method, apparatus, and system for selecting serving nodes for access

Publication Date: 2015.12.15 HUAWEI TECH CO LTD

AI summary

Embodiments of the present invention provide a method, an apparatus, and a system for selecting serving nodes for access, where the method includes: obtaining reference signal received parameters of at least two nodes; selecting a downlink serving node from the at least two nodes according to the reference signal received parameter of each node; and sending an uplink signal, so that the downlink serving node selects an uplink serving node from the at least two nodes according to the uplink signal; or, selecting an uplink serving node from the at least two nodes according to the reference signal received parameter of each node, and sending an uplink signal. In the embodiments of the present invention, a user equipment selects a downlink serving node from at least two nodes according to the reference signal received parameter of each node; then the user equipment sends an uplink signal.