Network Scheduling for Wireless Broadcast Uplink Interference

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current wireless communication systems face challenges in minimizing interference between downlink unicast and broadcast services, particularly when using unpaired spectrum for broadcast services within the duplex spacing of a paired unicast carrier, leading to increased costs and reduced coverage due to inefficient duplexer designs.

Innovation Solution

The solution involves network-based scheduling of time-slotted downlink broadcast transmissions to avoid concurrent operation with uplink unicast transmissions, allowing UEs to operate in half-duplex mode or with additional filtering, and informing the network of decoded broadcast services to schedule unicast and broadcast transmissions accordingly, preventing uplink interference with downlink broadcasts.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If downlink broadcast transmissions are scheduled within the duplex spacing of unicast carrier, then spectrum efficiency is improved, but uplink unicast transmissions interfere with downlink broadcast reception

Engineering Contradiction:
Improvespectrum efficiencyVSAvoiduplink interference with downlink broadcast
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent implements time-division multiplexing where downlink broadcast transmissions are scheduled in specific time slots that are periodic and coordinated with uplink unicast transmission slots. This ensures that broadcast downlink transmissions occur only when no uplink unicast transmissions are taking place, eliminating interference while maintaining efficient spectrum utilization through structured periodic scheduling

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The network controller pre-schedules broadcast downlink transmissions in time slots that are determined to be free from uplink unicast interference. By planning and allocating these time slots in advance based on uplink scheduling information, the system proactively prevents interference before it occurs, allowing UEs to efficiently receive broadcasts without conflict

Inventive Principle:
Principle #10Preliminary action

2Object-affected harmful factors

If additional filtering is added to UEs to reduce interference, then interference reduction is improved, but device complexity and cost increase

Engineering Contradiction:
Improveinterference reductionVSAvoidduplexer design complexity
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The patent introduces a network controller as an intermediary that coordinates between uplink unicast scheduling and downlink broadcast scheduling. This central controller manages the time slot allocation and provides scheduling information to UEs, eliminating the need for complex interference mitigation hardware in each UE. The coordination function acts as a mediator that resolves interference through intelligent resource allocation rather than hardware complexity

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The system implements feedback mechanisms where UEs report their broadcast reception status and the network controller adjusts scheduling decisions based on this feedback. This closed-loop control allows the system to optimize time slot allocation dynamically, maintaining interference-free operation without requiring complex filtering hardware in the UEs

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP1938524B1Compatible broadcast downlink and unicast uplink interference reduction for a wireless communication system
Publication Date: 2016.03.30 INTELLECTUAL VENTURES HOLDING 81 LLC
  • EP1938524B1 patent drawingFigure 1a~1b
  • EP1938524B1 patent drawingFigure 2
  • EP1938524B1 patent drawingFigure 3

AI summary

Embodiments of the current invention reduce interference from a mobile station (UE) uplink transmission to a received broadcast downlink transmission through a network-based scheduling of time-slotted downlink broadcast transmissions, so that they do not occur concurrently with uplink transmissions. The invention allows low cost, low power UEs to be designed and built by use of the following techniques: (i) downlink broadcast transmissions are time-slotted; (ii) UEs operate either in half-duplex mode for transmission and reception of unicast services, or in full duplex mode where additional bandpass or additional highpass filtering can be applied to the DL unicast carrier; (iii) when unicast services are active for a UE, the UE informs the network of the broadcast services that are being decoded; and (iv) the network schedules unicast transmissions, broadcast transmissions, or both unicast and broadcast transmissions such that the uplink unicast transmission to a UE is never time- coincident with the broadcast transmissions to that UE.