A hands-free system consisting of a transmitter and receiver that enables wireless speech-based instrument control via free-space optics (FSO) with infrared radiation, converting speech to Standard Commands for Programmable Instruments (SCPI) instructions and executes them.
The Problem
Current Situation
Engineers require both their hands during radiofrequency (RF) testing, for example, during interference hunting with one hand carrying a test instrument and the other holding an antenna. Hence, manually adjusting the settings is inconvenient and results in a loss of productivity. However, there are currently no non-RF wireless communication systems that can be used to control the test instrument without interfering with their testing.
Project Objective
To develop a hands-free system for engineers to adjust the settings of the test instrument using voice commands over free space optical communication.
Our Solution
Key Product Features
1. Headset with microphone
• Voice: Captures voice at close distance to maximize audio clarity and accuracy even in noisy environments.
2. Transmission of data with infrared radiation (IR) LEDs
• Wireless: Prevents tripping hazard and allows for greater mobility
• Designed for RF test instruments: IR prevents interference with RF test instrument measurements
• Human-friendly: Safe for eyes as IR is not glaring to the eyes
• Efficient system: High data transmission up to 2 meters even under indoor ambient light
3. Powered by AI
• Trigger word detection: Trigger word detection is used to start the system
• Speech to Text: Converts speech to text
4. Supports Standard Commands for Programmable Instruments(SCPI)
• Text to SCPI: Converts text to SCPI commands
• SCPI commands: Supports sending of SCPI commands to test instruments
Optical Data Transmission System
Specifications
• Transmission rate: 400 kbits/s
• Distance of transmission: up to 2 meters
• Angle coverage: ±60° horizontal, ±20° vertical
• Low power usage: 1.08 W max
• Zero to low transmission loss even at a distance of 2 meters
Transmitter iPerf results
Receiver iPerf results
Speech to SCPI System
Powered by AI
• Trigger word detection using model trained with CNN
• Speech to text using Julius speech recognition
• Text to SCPI command
Feature Extraction: MFCC
Model: CNN
• NN Classifier
• Accuracy: 97.5%
• Loss: 0.11
_Noise
_Unknown
Hey_Photon
_Noise
99.0%
1.0%
0.0%
_Unknown
3.5%
94.8%
1.7%
Hey_Photon
0.7%
0.6%
98.6%
F1 Score
0.97
0.96
0.98
Video demonstation of converting speech to SCPI commands
Poster
About Rohde & Schwarz
Rohde & Schwarz (R&S) is an international electronics product development company that specializes in creating radiofrequency (RF) test and measurement instruments for broadcast and media, radiocommunications and network technology industries. With its tremendous success for over 85 years, the German company has expanded its business to over 70 countries, with 2 regional headquarters established in the United States, Columbia, Maryland and in Singapore.