The nonlinear dynamics of an optically injected semiconductor laser are explored for radio-over-fiber uplink transmission. Under optical injection locking, the laser at the base station is operated in the period-one oscillation state, where its intensity oscillates at a tunable microwave frequency. When the oscillation is tuned to the subcarrier frequency, it is further locked by the uplink mic...

Airborne passive-microwave signatures collected in Northern Finland during EMAC-95 are analyzed with the emphasis on forested areas and dry snow conditions. The microwave signatures cover the 6.8–18.7-GHz frequency range and were acquired at both vertical and horizontal polarizations. The analysis is carried out with respect to the forest-stem volume data and comprises three different snow-dept...

A technique for the frequency multiplication of microwave signals based on the combination of two optical nonlinear phenomena in a single nonlinear fiber is investigated. Multiple four-wave mixing is used to generate harmonics on an externally modulated optical carrier while polarization pulling through stimulated Brillouin scattering is used to filter the desired harmonics. Microwave signals i...

There has been increased interest in the use and manipulation of optical fields to address the challenging problems that have traditionally been approached with microwave electronics. Some examples that benefit from the low transmission loss, agile modulation and large bandwidths accessible with coherent optical systems include signal distribution, arbitrary waveform generation and novel imagin...

A first order of DWA (Data Weighted Averaging) algorithm with third order sigma-delta modulator is proposed for application in sigma-delta fractional-N frequency synthesizer for WiMAX. In addition, this paper discusses the impact of mismatch between Digital-to-Analog convertor (DAC) unit elements. The simulation results show the effectiveness of the DWA technique in reduction of spurs, also DWA...

The superconducting Monolithic Microwave Integrated Circuit (MMIC) is vital in all modern superconducting Rapid Single Flux Quantum (RSFQ) digital systems. Importance of microwave components comes from the fact that superconducting circuits operate with an ultra-wide band signal in the ultra-low dissipation environment. At a typical signal bandwidth of 300 GHz, even a 100μm superconducting wire...

We investigate, by experiments and numerical simulations, thermal activation processes of Josephson tunnel junctions in the presence of microwave radiation. When the applied signal resonates with the Josephson plasma frequency oscillations, the switching current may become multivalued in a temperature range far exceeding the classical to quantum crossover temperature. Plots of the switching cur...

A number of advances in the use of metamaterial-inspired constructs to improve the overall efficiency, directivity and bandwidth performance of electrically small antennas (ESAs) in the VHF, UHF and microwave regimes will be reviewed. Several metamaterial-inspired ESA designs have been fabricated and tested; these measurement results are in nice agreement with predictions. While initial efforts...

We consider a theoretical model for a nonlinear nanomechanical resonator coupled to a superconducting microwave resonator. The nanomechanical resonator is driven parametrically at twice its resonance frequency, while the superconducting microwave resonator is driven with two tones that differ in frequency by an amount equal to the parametric driving frequency. We show that the semiclassical app...