Telephone Secondary Speaker Eavesdropping Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In public and shared office environments, private telephone conversations are often susceptible to being overheard by unintended third parties, as existing technologies lack effective methods to prevent eavesdropping.
Innovation Solution
The implementation of a secondary speaker in telephones that generates pseudorandom noise or cancellation signals, which are then subtracted from the received signal to isolate the voice signals of both local and remote participants, effectively canceling out the noise and preventing eavesdropping.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If audio stimulus signal is presented through secondary speaker to prevent eavesdropping, then privacy of telephone conversation is improved, but the audio stimulus signal may significantly impair the conversation for the participants
Solution Approach 1:
The system uses feedback by capturing the audio stimulus signal through a microphone, processing it to generate a cancellation signal, and then presenting this cancellation signal through the secondary speaker. This feedback loop ensures that the cancellation signal is precisely tailored to counteract the audio stimulus signal, thereby preventing eavesdropping while maintaining conversation quality for the participants.
Solution Approach 2:
The system converts the harmful audio stimulus signal (which could be overheard by eavesdroppers) into a beneficial cancellation signal. By processing the audio stimulus signal through a microphone and generating an inverted version, the system transforms the harmful leakage into a useful tool for active noise cancellation, thereby protecting privacy without degrading the conversation experience for legitimate participants.
2Object-affected harmful factors
If audio stimulus signal is used to cancel feedback and isolate voice signal, then eavesdropping prevention is improved, but device complexity increases due to additional processing requirements
Solution Approach 1:
The system employs self-service by using its own audio stimulus signal as the input for generating the cancellation signal. The microphone captures the audio stimulus signal produced by the secondary speaker, and the processor generates the cancellation signal based on this captured signal. This self-referential approach eliminates the need for external reference signals or complex adaptive algorithms, thereby reducing device complexity while achieving effective feedback cancellation.
3Object-affected harmful factors
If secondary speaker presents cancellation signal to isolate remote participant voice, then privacy of remote portion is improved, but loss of information increases due to signal subtraction
Solution Approach 1:
The system applies preliminary anti-action by generating and presenting the cancellation signal before an eavesdropper can capture the remote participant's voice through the secondary speaker. The cancellation signal is created by capturing the audio stimulus signal with a microphone and processing it to produce an inverted version, which is then presented through the secondary speaker to preemptively cancel any potential leakage, thereby protecting privacy without compromising voice signal integrity for legitimate participants.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution ensures that the intended participants can have a private conversation without interference, while the eavesdropper hears only noise or nothing, effectively preventing them from overhearing the conversation.
Implementation Method 1
the audio stimulus signal is subtracted from the received signal prior to presenting the received signal to the user to isolate the voice signal of the remote participant. To prevent the third party from listening to the remote portion of the conversation, the audio stimulus signal is subtracted from the received signal to isolate the voice signal of the remote participant. In this manner, the subtraction cancels the feedback of the audio stimulus signal that would otherwise be received by the user of the telephone.
Data Source
AI summary
Methods and apparatus are provided for preventing a third party from listening to a conversation between at least two participants on a telephone. The telephone generates an audio stimulus signal that is presented through a secondary speaker. The audio stimulus signal may be, for example, pseudorandom noise or a cancellation signal. According to one aspect of the invention, the telephone ensures that the audio stimulus signal does not significantly impair the conversation for the at least two participants. To prevent the third party from listening to the local portion of the conversation, the audio stimulus signal is subtracted from the received signal prior to presenting the received signal to the user. To prevent the third party from listening to the remote portion of the conversation, the audio stimulus signal is subtracted from the received signal.