Optical Carrier transmission rates

About: Optical Carrier transmission rates is a research topic. Over the lifetime, 2463 publications have been published within this topic receiving 33293 citations.

A 50 Mbit/s Optical Wireless LAN Link Using Novel Optical and Electronic Enabling Technologies

Abstract: Optical wireless transmission is proposed for the implementation of broadband wireless LANs. An optical cellular structure, which uses holograms to define optical cells and high levels of optical concentration in the receivers, will maximise the performance of such a system. The bootstrapping circuit technique can be used in the optical receiver design to give wideband and low noise operation in the presence of a large photodiode capacitance. Results for a 50Mbit/s link that operates over a 5m2 cell size are given.

System and method for simulating targets for a radar receiver utilizing an optical link

Abstract: Both a system and a method for simulating targets for a radar system is disclosed herein which generally comprises a test target generator having an input slaved to the pulse transmit frequencies of the radar system for generating a target simulating signal, a horn antenna for emitting the target simulating signal back to the radar receiver, a laser-operated optical transmission link having a single mode fiber optic cable for transmitting the target simulating signal from the test target generator to the horn antenna via optical carrier, and an amplification and processing circuit system connected between the output of the optical transmission link and the input of the horn antenna for increasing the amplitude of the target simulating signal to a level that is detectable by the radar receiver, and for further processing the signal. The test target generator also generates control signals indicative of a desired amplitude of the resulting target simulating signal, and the system preferably includes a controller in the form of a microprocessor whose input receives the control signal generated by the target generator, and whose output is connected to the amplifier system of the amplification and processing circuit. A phase shift circuit may be included in the processing circuit for both compensating for phase distortions that result from the impedances inherent in the remote transmission of the target simulating signal, and for providing a further means for selectively modifying the signature characteristics of the target simulating signal.

Coherent encoding of optical FSK header for all optical label swapping systems

Abstract: A numerical investigation on the limits of the optical frequency shift keying (FSK) label coding technique is presented, as well as an optimization of the critical parameters involved into it. The principle of the technique concerns a typical FSK modulated label, combined with an intensity modulated (IM) payload on the same optical carrier, via four-wave mixing (FWM) in a semiconductor optical amplifier (SOA). Simulations have been carried out for an intensity modulated nonreturn to zero (NRZ) 10-Gbs payload combined with a 625-Mbs FSK modulated header. The influence of the key parameters of the method such as the extinction ratio (ER) of the signal, the dynamic range of the FWM module and the FSK tone spacing have been investigated in combination with the system limitations, related to the propagating distance and the number of intermediate label swapping nodes. A 2R regeneration stage responsible for the label removal and reinsertion, and for the payload wavelength conversion and regeneration, has been adopted, based on a single Mach-Zender interferometer (MZI)-SOA stage. The FSK encoded label transmitter includes a compensation scheme for the removal of the residual amplitude intensity effect that FSK label causes on the IM modulated payload. A detailed numerical model has been implemented for the description of the FWM, due to its decisive role in the proposed architecture. It was found that it is possible to have successful (Q factor higher than 6 for both payload and header) transmission over five, 50-km spaced hops and assuming 10-Gbs payload with 625-Mbs header.

Radiophotonic method for instantaneous frequency measurement based on principles of “frequency-amplitude” conversion in Fiber Bragg grating and additional frequency separation

Abstract: This article describes the design principles of optoelectronic system (OES) for instantaneous frequency measurement (IFM) of microwave signals based on the use of amplitude-phase modulation conversion of single optical carrier into symmetrical dual-frequency signal for additional frequency separation, its modulation by unknown frequency and subsequent “frequency-amplitude” measurement conversion in Fiber Bragg Grating (FBG) with Gaussian reflection profile. Such approach allows increasing of measurement resolution at low frequencies.

Dynamics of all-optical clock recovery using two-section index- and gain-coupled DFB lasers

Abstract: The dynamics of coherent clock recovery (CR) using self-pulsing two-section distributed feedback (TS-DFB) lasers have been investigated. Both simulation and experimental results indicate fast lockup and walk-off of the clock-recovery process on the order of nanoseconds. Phase stability of the recovered clock from a pseudorandom bit sequence (PRBS) signal can be achieved by limiting the detuning between the frequency of free-running self-pulsation and the input bit rate. The simulation results show that all-optical clock recovery using TS-DFB lasers can maintain a better than 5% clock phase stability for large variations in power, bit rate, and optical carrier frequency of the input data and therefore is suitable for applications in optical packet switching.