As a single-channel demodulation system can detect only a limited number（up to a dozen）of grating wavelengths a time and it is necessary to take into account the stability and high speed of both the Fiber Bragg Grating（FBG）demodulation system and host computer communications

a multi-channel

multi-communication-port FBG demodulation system is developed using the Wavelength Division Multiplexing（WDM）and Spatial Division Multiplexing（SDM）technologies.By controlling the lightpath switching of a 16-channel optical switch

the SDM of the 16-channel FBG sensing network and the demodulating of the center wavelength in each channel sensor can be realized.Test results show that the center wavelength resolution of the demodulation system is 1pm and the time for collecting the granting wavelength information once is 620 ms

the minimum time for updating 16-channel FBG sensor information is not longer than 10 s.In addition

it is possible to effectively monitor about200 fiber grating sensors.