National Science Council

Shyh-Lin Tsao

Jing-Shown Wu

Hao-Chih Yu

Che-Li Lin

Yi-Chih Lin

Jingshown Wu

Tai-Chi Liu

Chui-Fwu Tsai

An optical communication system suitable for a coherent optical satellite communication is configured to include an optical transmission device having a laser signal generator, a first reference laser signal generator having a first local oscillating laser signal generator and an automatic frequency controller, an optical receiving device, and a second reference optical signal generator having a second local oscillating laser signal generator. The first reference local oscillating laser signal generator and the automatic frequency controller are used to generate a fixed beat reference optical signal, and thus the optical receiving device is capable of locking the transmitted laser signal according to the fixed beat reference laser signal in a way of heterodyne receiving so as to demodulate the transmitted signal frequency accurately and resolve the problem of laser frequency drifting.

Optical communication system

A coherent optical communication receiver of a satellite optical communication system, having a telescope, an automatic frequency control circuit and a frequency shift keying demodulator. The automatic frequency control circuit has a local oscillating laser, a light polarization controller, a optical coupler, a photo-detector, a microwave matching network, a microwave mixer, a frequency discriminator and a low pass frequency filter. The coherent optical communication receiver can receive a frequency control signal of a distant laser signal to perform a heterodyne receiving between the emitter and the receiver distant away from each other. With the consideration of the decay of vibration and atmosphere, the quality of the satellite optical communication can still be maintained. The structure and fabrication of the receiver are simple with a low fabrication cost, and the receiver is suitable for being applied to high speed satellite communication system.

Coherent optical communication receiver of satellite optical communication system

A probe of two-way optical component network analyzer. The probe includes an electrical circulator, an optical transmitter, an optical receiver, and an optical circulator. The electrical circulator is connected to a network analyzer, an optical transmitter and an optical receiver respectively. Electrical signals from the network analyzer are sent to the optical transmitter via the electrical circulator. The electrical circulator is capable of picking up electrical signals from the optical receiver and transmitting the electrical signals back to the network analyzer. Since electrical signals from different devices are separated inside the electrical circulator, electrical interference is prevented. The optical circular is coupled to the optical element, the optical transmitter and the optical receiver respectively. The optical circulator directs optical signals from the optical transmitter to the optical element and transfer optical signals from the optical element to the optical receiver. Since optical signals from different source are de-coupled inside the optical circulator, optical interference is prevented. The optical transmitter is a device for converting electrical signals to optical signals, and the optical receiver is a device for converting optical signals back to electrical signals.

Probe of two-way optical component network analyzer

The present invention discloses an encoder and a decoder that are tunable, controllable, and have low amount of energy loss during encoding or decoding. The encoder comprises a 2&times;2 EO coupler, and an optical recirculating loop (waveguide) which comprises a semiconductor optic amplifier. The decoder comprises a 2&times;2 EO coupler, an optical recirculating loop (waveguide) which comprises a semiconductor optic amplifier, a light detector, and a bit determining device. Thus, the structures of the encoder and the decoder are simple, and can be integrated on a photonic integrated circuit so that the reliability is increased and the cost of production decreased.

Tunable optical encoder and decoder

This invention proposed a temperature and optical frequency sensor using two different optical resonators. The fiber with different thermal expansion factor and refractive index can be used to sense the temperature variation. The optical resonators with different cavity lengths can be used to detect the frequency deviation. Applying a laser, a microprocessor and two optical resonators with different thermal expansion factors and resonate lengths, we invent the device which can detect the temperature and frequency simultaneously. Furthermore, the device can provide tunable and highly stabilized light source for optical system application.

Optical frequency and temperature sensor system

A new highly accurate temperature sensor for biomedical applications is proposed in this invention. This sensor including two fiber Bragg gratings with different thermal coefficients can accurately measure temperature with little laser frequency stabilization. This invention improves the measurement resolution and accuracy. Such a sensor can be used to calibrate the other fiber biomedical sensors when those fiber sensors are packaged together.

Growing community of inventors

Taipei Hsien, Taiwan

Shyh-Lin Tsao