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This paper proposes a method to detect photon counts from a commercial off-the-shelf SPAD array. Experiments show that using this method the sensitivity of a VLC receiver that incorporates this SPAD array approaches the limit set by Poisson noise.
Among the many photonic technologies available for antenna beamforming, those which provide flat RF response over a very wideband RF bandwidth, high signal to noise ratio, multiple-beam capabilities and minimum complexity are to be preferred.
This review presentation will look at the unique requirements for the antenna and beamformer for today's wideband systems which need high resolution. Unlike quasi monochromatic phased array technology, when dealing with wideband phased arrays, the designer needs to take into account the transfer function of the element as a function of scan angle, redefining the phased array problem and leading to...
A photonic beamformer is presented, having smooth behavior. Third-order nonlinearities, resulting from its optoelectronic components, are investigated, with emphasis on their impact on the contrast of imaging radars. This contrast is shown to be severely limited by the induced RF nonlinearities. Limitations on the allowable modulation index are studied for linearly-chirped pulses returned from clutter.
The authors proposed a photonic-crystal diode resonator capable of applying both DC-bias field and RF field at the same time, that enables the electron flow continuously to the anode regardless of the RF phase and amplitude as long as the modulation depth, the ratio of maximum RF voltage amplitude to DC-bias, is less than one. The proposed scheme employs a novel diode resonator consisting of two metal...
The impact that photodiode nonlinearities have on intensity-modulation direct-detection analog photonic links is described. The second- and third-order linearity requirements for photodiodes, quantified in terms of output intercept points, are calculated. Measured data at 1 GHz for a high-current (60-mA) partially-depleted-absorber photodiode are presented. A four-photodiode 26-mA array at 5 MHz is...
This paper reports on the analysis of technologies opening avenues for potential technological breakthroughs in phased array antennas. We will report on recent results on the insertion of hardware technologies such as RF MEMS and RF Photonics, in the front end of phased array antennas. Future prospects for the insertion of nanotechnologies will be also presented.
With the advent of new forms of true time delay wideband beamformers -both photonic and digital-the effect of noise within the beamformer channels must be taken into account. As an example, in this paper, a multibeam photonic beamformer for a phased array working in receive mode using linear frequency modulated pulses is analyzed. A general expression is obtained showing the effect of the optical...
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