Dynamic Spectral Resource Reallocation in Multiwaveform Base Stations

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The 900 MHz band restructuring for coexistence of narrowband LMR and broadband LTE communication poses challenges in supporting a large number of users during emergency situations, as LMR bandwidth is insufficient and degraded by out-of-band emissions from LTE systems.

Innovation Solution

A base station with shared RF spectrum allocation for narrowband and broadband transceivers, where an electronic processor dynamically adjusts the number of carrier channels and bandwidth to prioritize narrowband communication by reallocating resources from broadband to narrowband transceivers during increased demand, ensuring reliable voice communication while maintaining some LTE functionality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the 900 MHz band is restructured for coexistence of narrowband LMR and broadband LTE communication, then both LMR and LTE can operate simultaneously, but the LMR bandwidth becomes insufficient to support a large number of users during emergency situations

Engineering Contradiction:
Improvecoexistence capabilityVSAvoidLMR bandwidth
Core Design Contradiction:
Adaptability or versatilityVSQuantity of substance

Solution Approach 1:

The system dynamically adjusts the bandwidth allocation between LTE and LMR based on traffic conditions. During emergency situations when LMR traffic increases, the system reduces LTE bandwidth and reallocates those spectral resources to LMR, enabling the LMR bandwidth to expand from its static allocation to support more users dynamically

Inventive Principle:
Principle #15Dynamics

2Productivity

If LTE systems operate in the restructured 900 MHz band, then broadband communication is enabled, but out-of-band emissions from LTE systems degrade LMR communication quality

Engineering Contradiction:
Improvebroadband communication capabilityVSAvoidLMR communication quality
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The system implements dynamic monitoring and adjustment of spectral resources based on communication conditions. When LMR traffic increases or quality degrades due to LTE emissions, the system receives feedback and reallocates spectral resources to prioritize LMR, thereby maintaining LMR communication quality while managing LTE operations

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system applies different quality requirements to different communication types. LTE communication can tolerate higher interference and operates with standard quality thresholds, while LMR communication during emergencies is granted priority with stricter quality protection, allowing selective optimization of spectral allocation based on local communication needs

Inventive Principle:
Principle #3Local quality

3Reliability

If narrowband LMR uses high power to dominate signals transmitted by wideband LTE bearer, then voice calls are prioritized, but the system complexity increases

Engineering Contradiction:
Improvevoice call priorityVSAvoidsystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The base station implements a unified spectral resource management system that handles both LMR and LTE communications through a single dynamic allocation mechanism. This multi-functional approach consolidates what would otherwise require separate power control and resource management systems, reducing overall complexity while maintaining voice call priority through centralized control

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

Data Source

PatentEP4179675B1Reallocation of spectral resources in multiwaveform systems
Publication Date: 2024.07.24 MOTOROLA SOLUTIONS INC
  • EP4179675B1 patent drawingFigure 1A~1B
  • EP4179675B1 patent drawingFigure 2~3
  • EP4179675B1 patent drawingFigure 4

AI summary

Apparatus and method (300) for reallocation of spectral resources in multiwaveform systems. One embodiment provides a base station (110) operating in a narrowband spectrum and broadband spectrum that share a band allocation of RF spectrum. The base station (110) includes a narrowband transceiver (210), a broadband transceiver (220), and an electronic processor (250) coupled to the narrowband transceiver (210) and the broadband transceiver (220). The electronic processor (250) is configured to determine that a traffic load on the narrowband transceiver (210) is increasing and determine a number of additional carrier channels based on the traffic load to operate the narrowband transceiver (210) within a predefined blocking rate. The electronic processor (250) is also configured to reduce a bandwidth of the broadband transceiver (220) based on the number of additional carrier channels and assign additional carrier channels to the narrowband transceiver (210) to operate the narrowband transceiver (210) with the number of additional carrier channels.