Radio Communication Device Interference Scaling Circuit

Solution Overview

Problem

In cell-edge scenarios, mobile radio communication devices face strong inter-cell interference due to frequency reuse, which existing interference mitigation techniques struggle to address effectively, especially in asynchronous interferer scenarios and when residual CRS interference persists after initial cancellation methods.

Innovation Solution

A radio communication device with a noise level determination circuit, interference determination circuit, equalizer, and scaling circuit that exploits shift-dependent interference variations to scale PDCCH symbols and soft-bits, using a two-stage scaling method involving intra-symbol and inter-symbol scaling coefficients to enhance reliability and mitigate interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If frequency reuse is employed to increase network capacity, then system throughput is improved, but inter-cell interference increases at cell edges

Engineering Contradiction:

Improvenetwork throughputVSAvoidinter-cell interference

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent applies different scaling coefficients to different resource elements within the PDCCH based on their specific interference conditions. By identifying resource elements that are more susceptible to CRS interference and applying targeted scaling to those specific elements rather than uniformly scaling all PDCCH resources, the system maintains high throughput in low-interference areas while protecting against interference in vulnerable areas.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent dynamically adjusts the scaling coefficient parameter based on measured interference conditions. The scaling coefficient is determined by comparing reference signal received power (RSRP) measurements and adjusting the PDCCH transmission power accordingly. This parameter change allows the system to adapt to varying interference conditions and maintain optimal performance across different cell-edge scenarios.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If interference mitigation techniques are applied to reduce inter-cell interference, then PDCCH reliability is improved, but computational complexity increases

Engineering Contradiction:

ImprovePDCCH reception reliabilityVSAvoidcomputational complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies interference mitigation only to the extent necessary - by identifying and scaling only those resource elements that are most susceptible to CRS interference rather than applying complex mitigation techniques to all PDCCH resources. This partial action approach achieves sufficient reliability improvement without the full computational burden of comprehensive interference cancellation methods.

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The patent performs preliminary identification of CRS patterns and determines scaling coefficients before actual PDCCH transmission. By pre-calculating the interference characteristics and preparing appropriate scaling factors in advance, the system avoids complex real-time computations during transmission, thereby reducing computational complexity while maintaining reliability.

Inventive Principle:

Principle #10Preliminary action

3Object-affected harmful factors

If uniform scaling of PDCCH resources is applied to mitigate interference, then interference resistance is improved, but transmission efficiency decreases

Engineering Contradiction:

Improveinterference resistanceVSAvoidtransmission efficiency

Core Design Contradiction:

Object-affected harmful factorsVSProductivity

Solution Approach 1:

The patent applies different scaling coefficients to different resource elements within the PDCCH based on their specific interference conditions. By identifying resource elements that are more susceptible to CRS interference and applying targeted scaling to those specific elements rather than uniformly scaling all PDCCH resources, the system maintains high throughput in low-interference areas while protecting against interference in vulnerable areas.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent applies interference mitigation only to the extent necessary - by identifying and scaling only those resource elements that are most susceptible to CRS interference rather than applying complex mitigation techniques to all PDCCH resources. This partial action approach achieves sufficient reliability improvement without the full computational burden of comprehensive interference cancellation methods.

Inventive Principle:

Principle #16Partial or excessive action

Data Source

PatentUS9673850B2Radio communication devices and methods for controlling a radio communication device

Publication Date: 2017.06.06 APPLE INC

AI summary

A radio communication device is described comprising: a receiver configured to receive radio signals on a radio channel; a noise level determination circuit configured to determine a noise level of the radio signals; an interference determination circuit configured to determine interference information indicating an amount of interference of the radio signals with other signals; an equalizer configured to determine a softbit based on the radio signals and based on the noise level; and a scaling circuit configured to scale based on the determined interference information at least one of the noise level or the softbit.