Performance of Instantaneous Microwave Analysis by Parametric Channelized Receiver Through Time Domain Monitoring

Abstract

For many applications, ranging from commercial, surveillance, or defense, it is essential to analyze the frequency components of a captured microwave signal over a wide bandwidth in real time and with high resolution. Various photonic approaches have been proposed for the processing of wideband microwave signals in order to overcome limitations imposed by conventional electronic frequency measurements. Here, we present the performance analysis and characterization of a parametric channelized receiver with 275 MHz resolution defined by the Fabry-Perot 3 dB bandwidth and 1 GHz step. Our approach relies on the generation of high quality copies of the RF input by self-seeding wavelength multicasting in a two-pump parametric mixer. Periodic filtering using off-the-shelf elements is then performed on the multicast beam. Ease of filtering is thus achieved by relying on frequency nondegeneracy of the newly generated copies. In this paper, instantaneous analysis of the incoming microwave signal is demonstrated by simultaneous monitoring five of the generated parametric copies while transmitting a frequency-hopping pattern. Operating margins in terms of optical and microwave powers are studied using the five-channel data simultaneously collected on a real-time oscilloscope. Dynamic range adjustments through optical power tuning of the input signal seed are demonstrated. Finally, the effects of frequency mapping detuning are observed to determine optimal operating conditions.

Subnoise detection of a fast random event

“…Previous experiments on BOA failure showed that highly vibrationally excited molecules exhibit efficient vibrational relaxation when they collide with a clean single-crystal metal surface, whereas little relaxation is seen with insulators (14,15). This comparison showed the importance of electronic excitation by molecular vibration, a phenomenon that could also be investigated with first-principles theory (16,17).…”

“…1). In the optical domain, the received spectrum can be parametrically cloned (8) and subsequently decomposed by a single physical filter (14). This strategy cannot be applied in spectral ranges where efficient, low-noise parametric mixers (15,16) do not exist.…”