Intercom Trunk Gain Control for Individual Audio Sources

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing intercom systems face challenges in dynamically controlling the volume levels of multiple audio streams over trunked connections, as adjustments made at the local intercom affect all conversations on the trunk, preventing individual volume control for specific audio sources.

Innovation Solution

Implementing a system with an electronic processor that applies trunk gain values to crosspoints based on remote keypanel requests, allowing independent volume adjustments for each audio stream received over trunk connections.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If local audio adjustment is applied to trunk connections, then all conversations carried over the trunk are affected uniformly, but individual volume control for specific audio sources is lost

Engineering Contradiction:
Improvevolume controlVSAvoidindividual source control
Core Design Contradiction:
Ease of operationVSAdaptability or versatility

Solution Approach 1:

The patent segments the audio adjustment function by creating separate gain control mechanisms for each audio source entering the intercom through different trunk lines. Instead of a single uniform adjustment for all trunk audio, the system implements source-specific gain controls that allow independent volume regulation for each conversation stream, resolving the contradiction between uniform control simplicity and individual source adaptability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies local quality by making the audio adjustment properties specific to each audio source rather than uniform across all trunk connections. Each trunk line's audio input is assigned its own gain parameter that can be independently adjusted, allowing the system to optimize volume for each specific conversation while maintaining the shared trunk infrastructure.

Inventive Principle:
Principle #3Local quality

2Adaptability or versatility

If audio adjustment is applied dynamically based on trunk selection, then flexibility is improved, but system complexity increases

Engineering Contradiction:
Improvedynamic adjustmentVSAvoidcontrol mechanism
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent implements preliminary action by pre-configuring gain parameters for each trunk line and audio source before calls are established. The system maintains a database of gain settings that are automatically applied when trunk connections are formed, eliminating the need for complex real-time dynamic adjustment logic while still providing flexible source-specific volume control.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system employs self-service by automatically applying the appropriate gain settings based on which trunk line is active and which audio sources are present. The intercom controller autonomously selects and applies the correct gain parameters without requiring manual intervention or complex user configuration, simplifying the control mechanism while maintaining dynamic adaptability.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP4229860B1Volume control over shared trunk lines in intercom systems
Publication Date: 2025.09.17 ROBERT BOSCH GMBH
  • EP4229860B1 patent drawingFigure 1
  • EP4229860B1 patent drawingFigure 2
  • EP4229860B1 patent drawingFigure 3

AI summary

Systems and methods for volume control over intercom trunk lines. One example method includes receiving, from a first keypanel coupled to a first intercom, a call request identifying a remote keypanel coupled to a second intercom. The method includes transmitting a trunk request based on the call request and receiving a trunk setup message. The method includes activating a first crosspoint to provide a two-way audio connection between the first and second intercom devices. The method includes applying a trunk gain value to the first crosspoint based on the remote keypanel and transmitting, with an audio gain based on the trunk gain value, an audio stream received from the first keypanel. The method includes receiving, from the second intercom, a gain adjustment value associated with the first keypanel and the remote keypanel and applying an adjusted trunk gain value to the first crosspoint based on the gain adjustment value.