Coverage Enhancing Device Frequency Offset for Interference Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Coverage enhancing devices (CEDs) in wireless communication systems suffer from increased interference due to parasitic reflections, which can lead to destructive superposition of signals at receiver nodes, affecting communication efficiency.
Innovation Solution
A method and device configuration that allows a coverage enhancing device controlling node to transmit a frequency offset parameter to a CED, enabling the CED to frequency translate retransmitted signals. This configuration ensures that the retransmitted signals do not overlap with direct signals in frequency allocation, reducing interference at receiver nodes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a CED is used to improve signal coverage, then coverage enhancement is achieved, but interference is increased due to parasitic reflections
Solution Approach 1:
The patent applies frequency shifting to translate the reflected signal into a different frequency domain, separating it from the direct signal in the frequency dimension. This allows the CED to provide coverage enhancement while avoiding interference by operating in different frequency spaces for direct and reflected paths.
Solution Approach 2:
The patent changes the frequency parameter of the reflected signal by applying a frequency offset. This parameter change transforms the reflected signal from overlapping with the direct signal in frequency to being separated, thereby reducing interference while maintaining coverage enhancement benefits.
2Power
If phase setting is optimized for specific incoming and outgoing angles, then beamforming gain is improved, but parasitic reflections affect a wide range of directional pairs
Solution Approach 1:
The patent moves the control from spatial dimension (angle-specific phase settings) to frequency dimension (global frequency offset). This allows a single frequency offset configuration to benefit all directional pairs simultaneously, resolving the conflict between optimizing for specific angles and avoiding parasitic effects across wide angular ranges.
3Reliability
If the CED applies gain to reflected signals, then signal coverage is enhanced, but interference is amplified
Solution Approach 1:
The patent separates the enhanced reflected signal into a different frequency domain through frequency shifting. This allows the CED to apply gain for coverage enhancement while the frequency separation prevents the amplified signal from causing interference to direct path communications.
4Object-generated harmful factors
If frequency offset is applied to retransmitted signals, then destructive superposition is reduced, but device complexity increases
Solution Approach 1:
The patent introduces a frequency offset parameter as an intermediary control mechanism. This single parameter, configured by a controlling node, mediates between the direct and reflected signals to prevent destructive superposition without requiring complex processing or multiple control parameters at the CED.
Data Source
AI summary
A method is disclosed, performed by a coverage enhancing device controlling node, for controlling a coverage enhancing device (CED). The method comprises transmitting, to the CED, a first configuration message, the first configuration message comprising a frequency offset parameter being indicative of a frequency offset to be applied by the CED.