Master Scheduler for Multi-Carrier Forward Link Scheduling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing wireless communication systems face inefficiencies in scheduling transmissions, particularly in packet-switched systems where VoIP and other delay-sensitive applications struggle with equal delay allocation, leading to suboptimal resource utilization and reduced system capacity.

Innovation Solution

A forward link scheduler is implemented with a master scheduler and packet builder, using a processor to select packets based on a highest packet metric across multiple carriers, prioritizing expedited forwarding flows and varying delay allocation based on load and coverage to optimize resource use and increase system capacity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If equal delay allocation is used for all users in packet-switched systems, then simplicity of scheduling is maintained, but system capacity and resource utilization are reduced

Engineering Contradiction:
Improvesystem capacityVSAvoidscheduling complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent implements dynamic delay allocation where the scheduler adjusts delay parameters adaptively based on current system conditions, user priorities, and traffic patterns. The master scheduler dynamically determines non-equal delay allocations for different users and carriers, transforming the static equal-delay approach into a dynamic system that optimizes capacity while managing complexity through adaptive control

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the delay parameter from a fixed equal value to variable non-equal values based on user priority, traffic type, and carrier conditions. By modifying the delay parameter dynamically across different users and carriers, the system achieves higher capacity utilization while the hierarchical scheduler structure manages the resulting complexity

Inventive Principle:
Principle #35Parameter changes

2Productivity

If non-equal delay allocation is implemented to optimize resource utilization, then system capacity increases, but scheduling complexity increases

Engineering Contradiction:
Improveresource utilizationVSAvoidscheduling complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent segments the scheduling function into hierarchical layers: a master scheduler that makes high-level decisions about carrier selection and overall resource allocation, and individual packet builders for each carrier that handle specific packet construction. This segmentation distributes the complexity of non-equal delay allocation across multiple simplified components rather than requiring one complex centralized scheduler

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The master scheduler acts as an intermediary between the packet sources and the individual carrier packet builders. It receives packet candidates from multiple carriers, applies the non-equal delay allocation logic, and selects which packets to forward to which carriers. This intermediary structure simplifies the overall system by centralizing the complex decision-making while keeping individual carrier operations simple

Inventive Principle:
Principle #24Intermediary (Mediator)

3Loss of time

If expedited forwarding flows are prioritized across all carriers, then delay-sensitive applications improve, but throughput of other flows deteriorates

Engineering Contradiction:
Improvedelay for expedited flowsVSAvoidthroughput of other flows
Core Design Contradiction:
Loss of timeVSProductivity

Solution Approach 1:

The patent applies different delay allocation strategies locally to different carriers and different flow types. Each carrier can have its own packet builder that handles specific traffic types with appropriate delay parameters. Expedited flows receive priority on carriers optimized for low latency, while other carriers maintain configurations optimized for throughput, allowing each local component to have quality characteristics matched to its intended traffic type

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The master scheduler applies partial prioritization to expedited flows by selecting only the most critical packets for expedited handling while allowing other packets to follow normal scheduling. Rather than giving expedited flows excessive priority across all carriers, the system applies selective prioritization that achieves sufficient delay performance for time-sensitive applications while preserving throughput for other flows through balanced allocation

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP1989844B1Distributed forward link schedulers for multi-carrier communication systems
Publication Date: 2015.11.04 QUALCOMM INC
  • EP1989844B1 patent drawingFigure 1A
  • EP1989844B1 patent drawingFigure 1B
  • EP1989844B1 patent drawingFigure 2

AI summary

Embodiments disclosed here relate to scheduling packet transmission in a multi-carrier communication system. In an embodiment, a master scheduler having at least one processor and at least one memory operably connected to the at least one processor is adapted to execute instructions stored in the at least one memory, the instructions comprising selecting a packet with a highest packet metric from among candidate packets from one carrier of a plurality of carriers, whereby expedited forwarding flows do not have a higher metric on another carrier.