PTT Server Talkgroup Connection Timer Extension
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In Land Mobile Radio (LMR) communication systems, there is a delay in initiating talkgroup calls on Long Term Evolution (LTE) systems due to radios falling into idle mode after inactivity, leading to audio truncation and battery drainage, which is unacceptable for mission-critical use cases.
Innovation Solution
A system and method that utilizes a PTT Server to synchronize audio transmissions and maintain talkgroup radios in a connected state using an extended connection timer, eliminating the need for paging and reducing echo issues, thereby allowing immediate start of talkgroup calls without audio truncation and conserving battery life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If mobile radios fall into idle mode after inactivity to conserve battery, then battery life is extended, but call initiation delay increases due to paging requirements
Solution Approach 1:
The system performs preliminary actions by maintaining radios in connected mode longer than traditional systems would require, using historical statistics to predict upcoming calls. This preliminary extension of connected state prevents the need for paging delays when calls are actually initiated, as radios are already in the appropriate state to receive and transmit audio immediately.
Solution Approach 2:
The system dynamically adjusts the connection timeout period based on historical talkgroup statistics and predicted activity patterns. Rather than using a static timeout value, the system adapts the connected state duration to match actual usage patterns, extending connection time when calls are likely and allowing idle mode when activity is low, thus optimizing both battery life and call initiation speed.
2Reliability
If audio is delayed until all talkgroup radios are in connected mode, then audio truncation is avoided, but call start time is delayed
Solution Approach 1:
The system performs preliminary actions by maintaining radios in connected mode based on historical statistics, ensuring they are ready to receive audio immediately when a call is initiated. This preliminary preparation eliminates both the audio truncation problem (since radios are already connected) and the call start delay (since no paging is needed), resolving the contradiction between audio completeness and call start time.
3Use of energy by moving object
If paging cycle is extended to reduce paging frequency, then battery consumption is reduced, but call initiation reliability decreases
Solution Approach 1:
The system dynamically adjusts the effective paging interval by using historical statistics to predict when calls will occur and maintaining radios in connected mode during high-probability periods. This dynamic approach allows for longer actual idle periods (reducing battery consumption) while ensuring reliability is maintained through statistical prediction of call patterns, effectively decoupling the trade-off between battery consumption and call initiation reliability.
Data Source
AI summary
A method for extending the connection time of talkgroup radios in a talkgroup conversation based on historical talkgroup statistics is provided. A talkgroup conversation request intended for a talkgroup is received from a first mobile unit. A group call grant message is sent to radios that are members of the talkgroup. The group call grant message initiates the talkgroup conversation with a first talkgroup call and includes an extended connection time value. Once it is determined that the first talkgroup call has ended, all radios that are members of the talkgroup are kept in a connected state. An extended connection timer utilizing the extended connection time value is started. Upon expiration of the extended connection timer, all radios that are members of the talkgroup are set to an idle state.