Licensed-Unlicensed Carrier Aggregation for Seamless Mobile Bandwidth

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Solution Overview

Problem

Existing carrier aggregation technologies in cellular networks are limited to adjacent channels and do not effectively integrate licensed and unlicensed frequency bands, leading to separation in Internet Protocol flows between WLAN access and UMTS/LTE networks, which hinders seamless mobility and user experience.

Innovation Solution

Implementing carrier aggregation between a licensed frequency band and an unlicensed ISM band, using an alternating time slot scheme to enhance bandwidth, where a PCell operates on licensed LTE and an SCell operates on unlicensed LTE or other IEEE-802.11 technologies, with resource allocation controlled by the PCell.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If carrier aggregation is limited to adjacent channels only, then device complexity is reduced, but usable bandwidth is insufficient

Engineering Contradiction:
Improveusable bandwidthVSAvoiddevice complexity
Core Design Contradiction:
Quantity of substanceVSDevice complexity

Solution Approach 1:

The patent segments the frequency spectrum into licensed and unlicensed bands, allowing carrier aggregation across these separate segments. This enables the system to combine carriers from different frequency ranges (not just adjacent channels) to increase total usable bandwidth while managing complexity through structured resource allocation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The access point is designed with multi-functionality to handle both licensed and unlicensed band carriers simultaneously. It can perform carrier aggregation across different frequency types and manage multiple radio access technologies (LTE and WLAN), making the system versatile and adaptable to various bandwidth requirements.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Quantity of substance

If licensed and unlicensed bands are integrated, then usable bandwidth is enhanced, but separation in Internet Protocol flows between WLAN and cellular networks occurs

Engineering Contradiction:
Improveusable bandwidthVSAvoidseparation in IP flows
Core Design Contradiction:
Quantity of substanceVSEase of operation

Solution Approach 1:

The patent merges licensed and unlicensed band operations into a unified carrier aggregation framework. By integrating these bands under common resource allocation control from the access point, the system enhances bandwidth while maintaining unified management of IP flows, eliminating the separation issue between WLAN and cellular networks.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The access point acts as an intermediary that mediates between licensed and unlicensed band carriers. It performs centralized resource allocation and coordinate management, ensuring seamless integration of IP flows across different radio access technologies while maintaining ease of operation.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Productivity

If unlicensed bands are utilized for carrier aggregation, then network capacity increases, but interference from other WLAN users arises

Engineering Contradiction:
Improvenetwork capacityVSAvoidinterference from WLAN users
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent implements dynamic resource allocation in the unlicensed bands. The access point can adaptively adjust resource allocation based on detected interference levels and channel conditions, allowing the system to maximize network capacity while dynamically avoiding or mitigating interference from other WLAN users.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system incorporates feedback mechanisms to monitor interference levels in unlicensed bands. Based on this feedback, the access point adjusts resource allocation and transmission parameters to maintain high network capacity while minimizing the impact of interference from other WLAN users.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3528421B1Enhancing the usable bandwidth between an access point of a radio access network and a user equipment
Publication Date: 2025.07.16 DEUTSCHE TELEKOM AG
  • EP3528421B1 patent drawingFigure 1~3

AI summary

The invention is related to a method for enhancing the usable bandwidth between on the one hand an access point of a radio access network of a telecommunications network, and on the other hand a User Equipment of a subscriber of the telecommunications network, wherein the User Equipment and the access point mutually communicate based on a standardized mobile communication technology using carrier aggregation of at least a first communication carrier and a second communication carrier, wherein the first communication carrier has a first carrier frequency and wherein the second communication carrier has a second carrier frequency, wherein the first carrier frequency is a standardized and licensed frequency and related to the communication technology, and wherein the second carrier frequency is a frequency in a frequency range out of the following: -- from 6.765 to 6.795 MHz, -- from 13.553 to 13.567 MHz, -- from 26.957 to 27.283 MHz, -- from 40.66 to 40.70 MHz, -- from 433.05 to 434.79 MHz, -- from 902 to 928 MHz, -- from 2.400 to 2.500 GHz, -- from 5.725 to 5.875 GHz, -- from 24.00 GHz to 24.25 GHz, -- from 61.0 GHz to 61.5 GHz, -- from 122 GHz to 123 GHz and -- from 244 GHz to 246 GHz.