Low Duplex Spacing Bandwidth Fragmentation for Interference Suppression

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Solution Overview

Problem

Full-duplex (FD) communication systems face challenges such as self-interference, uncontrolled interference from non-coordinated devices, and scattering-caused interference, which hinder their widespread adoption due to complexity, cost, and inadequate interference suppression.

Innovation Solution

The implementation of low duplex spacing (LDS) communication systems, where a channel is partitioned into UL and DL portions with low duplex spacing, allowing simultaneous DL and UL transmissions with adequate signal isolation, reducing complexity and cost, and using signal compensation circuitry for interference reduction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If full-duplex communication is implemented to enable simultaneous transmit and receive over the same frequency channel, then spectral efficiency is improved, but self-interference and uncontrolled interference from non-coordinated devices increase

Engineering Contradiction:

Improvespectral efficiencyVSAvoidself-interference

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The channel bandwidth is segmented into multiple fragments with different spacing configurations. Some fragments use low duplex spacing for high spectral efficiency while others use higher spacing for better isolation, allowing simultaneous transmission and reception with controlled interference levels

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different fragments of the channel are assigned different duplex spacing characteristics based on local requirements. This allows each fragment to be optimized for its specific function, with some providing high efficiency and others providing interference suppression

Inventive Principle:

Principle #3Local quality

2Productivity

If full-duplex communication is implemented, then spectral efficiency is improved, but device complexity and cost increase

Engineering Contradiction:

Improvespectral efficiencyVSAvoidcomplexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

Instead of implementing full duplex across the entire channel which would require complex interference suppression, the system applies low duplex spacing only to specific fragments where it provides sufficient isolation, reducing the overall complexity while maintaining spectral efficiency benefits

Inventive Principle:

Principle #16Partial or excessive action

3Productivity

If low duplex spacing is used to partition the channel bandwidth, then bandwidth efficiency is improved, but interference suppression becomes more challenging

Engineering Contradiction:

Improvebandwidth efficiencyVSAvoidinterference

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The channel is divided into multiple fragments where low duplex spacing is applied to create efficient bandwidth utilization, while the segmented structure itself provides natural isolation that suppresses interference between simultaneous transmissions

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The bandwidth fragment structure acts as an intermediary that enables low duplex spacing while inherently providing interference suppression through the fragment boundaries and spacing design

Inventive Principle:

Principle #24Intermediary (Mediator)

4Loss of time

If low duplex spacing is used to partition the channel, then latency is reduced, but receiver complexity increases

Engineering Contradiction:

ImprovelatencyVSAvoidreceiver complexity

Core Design Contradiction:

Loss of timeVSDevice complexity

Solution Approach 1:

Low duplex spacing is applied only to the extent needed to achieve low latency, with the fragment structure providing sufficient isolation to avoid the need for complex receiver processing, thus achieving low latency without excessive complexity

Inventive Principle:

Principle #16Partial or excessive action

Data Source

PatentUS10476655B2Methods, apparatuses, systems, devices, and computer program products directed to low latency bandwidth efficient communications with low duplex spacing

Publication Date: 2019.11.12 INTERDIGITAL PATENT HOLDINGS INC

AI summary

Methods, apparatuses, systems, devices, and computer program products directed to low latency, bandwidth efficient communications with low duplex spacing (LDS) are provided. The LDS communications are facilitated by partitioning a (e.g., single) channel to include DL and UL portions (or “bandwidth fragments”) with low duplex spacing between the DL and UL portions. Among the new methodologies provided herein is a method that may include partitioning a channel to include a first bandwidth fragment that is bounded by, and overlaps or has low duplex spacing with, a pair of non-overlapping bandwidth fragments that are symmetrically offset symmetrically from a reference frequency associated with the channel; receiving a receive signal while transmitting a transmit signal on either the first bandwidth fragment or the pair non-overlapping bandwidth fragments; and using any of cancellation and interference reduction to reduce a portion of the receive signal that corresponds to the transmit signal.