Parallel instantaneous frequency measurement in a highly nonlinear fiber using wavelength labeling

A novel technique for instantaneous frequency measurement using all optical mixing with multiple simultaneous and parallel measurements is demonstrated. This technique requires no special selection of optical wavelengths and provides a systematic method to extend the systems to multiple measurements with only modest increment in component count. © 2011 IEEE

All optical instantaneous frequency measurement incorporating optical Hilbert transformer

A novel method to incorporate an optical Hilbert transformer with an all-optical photonic instantaneous frequency measurement system is proposed and demonstrated. Two orthogonal measurements of an RF signal are obtained which enables determination of both signal frequency and power. This system produces DC outputs that simplify the receiver and reduce cost. The system is demonstrated between DC and 20 GHz but can be scaled to 40 GHz and beyond. © 2012 IEEE

Amplitude independent instantaneous frequency measurement using all optical technique

A novel all-optical system which independently measures both the amplitude and frequency of an RF signal is proposed and demonstrated. A photonic Hilbert transformer provides two orthogonal measurements of an RF signal. These are compared using four wave mixing in a highly nonlinear fiber, producing two independent outputs enabling determination of both signal frequency and amplitude. This all optical approach requires only simple, low cost DC electronics at the receiver. The system is demonstrated up to 20 GHz but can be scaled to 40 GHz and beyond. © 2013 Optical Society of America

Parallel all-optical instantaneous frequency measurement system using channel labeling

A novel system, offering simultaneous and parallel instantaneous frequency measurements, is demonstrated. The choice of optical wavelengths is unconstrained and thus a practical approach for multiple instantaneous frequency measurements is achieved with only modest system complexity. © 2012 IEEE

Remoted all optical instantaneous frequency measurement system using nonlinear mixing in highly nonlinear optical fiber

A novel remoted instantaneous frequency measurement system using all optical mixing is demonstrated. This system copies an input intensity modulated optical carrier using four wave mixing, delays this copy and then mixes it with the original signal, to produce an output idler tone. The intensity of this output can be used to determine the RF frequency of the input signal. This system is inherently broadband and can be easily scaled beyond 40 GHz while maintaining a DC output which greatly simplifies receiving electronics. The remoted configuration isolates the sensitive and expensive receiver hardware from the signal sources and importantly allows the system to be added to existing microwave photonic implementations without modification of the transmission module. © 2013 Optical Society of America

Real time all optical correlator for serialized time encoded signals

A novel technique for correlation of spectrally encoded data is presented. Data encoded in the spectrum of ultrafast optical pulses is mapped into the time domain using dispersion and then mixed with a spectrally engineered broadband pump using four wave mixing to create a narrow bandwidth idler, which is isolated and electronically integrated. Unlike previous methods, this solution provides all-optical functionality at every stage of correlation. The demonstrated frame rate of 20 MHz is limited only by the laser repetition rate. ©2014 Elsevier B.V. All rights reserved

Optical correlation using four wave mixing in a highly nonlinear fibre for real-time serialized ultrafast systems

A method of all-optical correlation is proposed using the nonlinear phenomena Four Wave Mixing (FWM) of two different signals. The method shows a serial solution where correlation of an ultrafast real-time serialized broadband source is demonstrated using a Highly Non-Linear Fibre (HNLF) with correlation rate reaching 200MHz

Novel all optical serialised real time correlator using FWM and frequency to time mapping

A novel technique for obtaining the correlation of spectrally encoded information is presented. The information encoded in the spectrum of ultrafast optical pulses is mapped into time domain using dispersion and is then mixed with a spectrally engineered broadband pump using four wave mixing to create a narrow band idler. This idler could then be filtered and integrated using electronics. Unlike previous methods, all the stages, even template modulation, is carried out all optically. A correlation rate of 20MHz is demonstrated; but this is only limited by the repetition rate of the femtosecond fiber laser. © 2013 IEEE

Photonic instantaneous frequency measurement: Parallel simultaneous implementations in a single highly nonlinear fiber

A microwave photonic system that simultaneously implements multiple parallel instantaneous frequency measurement systems within a single highly nonlinear optical fiber is proposed and practically demonstrated. Three optical carriers of different wavelengths are modulated by the same radio-frequency (RF) signal and then delayed differentially. All three carriers are then mixed within a highly nonlinear optical fiber. The mixing products are separated, and the optical power of each is used to deduce input RF frequency. We demonstrate simultaneous acquisition of two distinct frequency measurement responses over the range from 1 to 40 GHz. This system is all-optical and requires no high-speed electronic components. Avenues for further increasing the number of simultaneous channels are identified. © 2009 IEEE

(IPC) A photonic correlation scheme using FWM with phase management to achieve optical subtraction

In this paper, a photonic correlation scheme that allows accumulation of negative signals is presented. The scheme uses four-wave mixing of pairs of signal and pump wavelengths, which are chosen such that they create idler wavelengths at a common wavelength. The total optical power at this target idler wavelength depends on the relative phase of each pump and signal wavelength. This concept has been applied to form a correlator where signal wavelengths are modulated by an input bit stream and mixed with pump wavelengths representing a reference bit pattern. This approach provides a correlation function with smaller unwanted noise peaks due to cancelation in the subtraction process. Simulation of the proposed correlation technique has been used to verify the concept using both intensity and phase modulation of the signal wavelengths. © 2009-2012 IEEE