A Wide Dynamics and Fast Scan Interrogating Method for a Fiber Bragg Grating Sensor Network Implemented Using Code Division Multiple Access

• Main Authors: Chang-Soo Park, Youngbok Kim, Sie-Wook Jeon, Won-Bae Kwon
• Format: Article
• Language: English
• Published: MDPI AG 2012-05-01
• Series: Sensors
• Subjects: optical sensor network; code division multiple access; fiber Bragg grating sensor; wavelength-to-time conversion; sliding correlation
• Online Access: http://www.mdpi.com/1424-8220/12/5/5888

We propose and demonstrate a fiber Bragg grating (FBG) sensor network employing the code division multiple access (CDMA) technique to identify information from individual sensors. To detect information without considering time delays between sensors, a sliding correlation method is applied, in which two different signals with the same pseudo-random binary sequence (PRBS) pattern, but slightly different frequencies, are applied to the source and detector sides. Moreover, for time domain detection, a wavelength-to-time conversion technique using a wavelength dispersive medium is introduced. The experimental results show that the proposed sensor network has a wide strain dynamic range of 2,400 μe and a low crosstalk of 950:1.