Second harmonic generation in reverse proton exchanged Lithium Niobate waveguides.

We investigate efficient second harmonic generation in reverse proton exchanged Lithium Niobate waveguides. In z-cut crystals, the resulting buried and surface guides support TM and TE polarizations, respectively, and are coupled through the d 31 nonlinear element. Numerically estimated conversion efficiencies in planar structures operating at 1.32microm reach 90% in 2cm or a normalized 14% microm/Wcm

Maritime surveillance via multi-frequency DVB-T based passive radar

In this paper, we consider the possibility to jointly exploit multiple frequency channels emitted by the same transmitter to improve target detection capability in a DVB-T based passive radar. In particular, appropriate multi-frequency techniques are presented for target detection to be effective in the considered application. The proposed approaches are validated and compared with reference to several experimental data for maritime surveillance applications. The reported results show that the considered multi-frequency techniques yield a significant enhancement in target detection performance with respect to the single frequency operation

Multi-Frequency Target Detection Techniques for DVB-T Based Passive Radar Sensors

This paper investigates the possibility to improve target detection capability in a DVB-T- based passive radar sensor by jointly exploiting multiple digital television channels broadcast by the same transmitter of opportunity. Based on the remarkable results obtained by such a multi-frequency approach using other signals of opportunity (i.e., FM radio broadcast transmissions), we propose appropriate modifications to the previously devised signal processing techniques for them to be effective in the newly considered scenarios. The resulting processing schemes are extensively applied against experimental DVB-T-based passive radar data pertaining to different surveillance applications. The obtained results clearly show the effectiveness of the proposed multi-frequency approaches and demonstrate their suitability for application in the considered scenarios