Ultrawideband monocycle generation using cross-phase modulation in a semiconductor optical amplifier

Abstract

We propose a novel scheme to generate ultrawideband (UWB) monocycle pulses based on cross-phase modulation (XPM) of a semiconductor optical amplifier (SOA). The proposed system consists of a SOA and an optical bandpass filter (OBF). Due to the XPM, a continuous wave (CW) probe signal is phase modulated by another optical Gauss pulse in the SOA. The OBF will convert the phase modulation to intensity modulation. A pair of polarity-reversed UWB monocycle pulses is achieved by locating the probe carrier at the positive and negative linear slopes of the OBF. Both cases conform to the UWB definition of the Federal Communications Commission.

Proposal for all-optical switchable and tunable ultrawideband monocycle generation utilizing SOA wavelength conversion and time delay

“…UWB signal generation in the optical domain is recently developed rapidly, because of the low loss over long-distance transmission in the optical fiber. Many electro-optical methods [3][4][5][6] and all-optical methods [7][8][9] have been proposed. Particularly, an optically switchable and tunable scheme has been demonstrated using the semiconductor optical amplifier (SOA) and single-mode fiber (SMF), but a long span of optical fiber should be used [10].…”

Photonic generation of background-free millimeter-wave ultra-wideband signals (Invited Paper)

“…The Federal Communications Commission (FCC) defined the UWB signal as a radio frequency (RF) signal that occupies a spectral bandwidth of more than 500 MHz or more than 20% fractional bandwidth with a power density no more than −41.3 dBm∕MHz [2] . Up to now, various approaches have been proposed to generate UWB signals in the centimeter-wave (CMW) band (3.1 to 10.6 GHz) for indoor communications [3][4][5][6][7] and in the millimeter-wave (MMW) band (22 to 29 GHz) for outdoor communications [8][9][10][11][12][13][14][15][16][17][18][19] . In this Review, we review recent progress on the photonic generation of UWB signals in the MMW band with emphasis on the generation of background-free and FCC compliant MMW-UWB pulses.…”

Fiber transmission and generation of ultrawideband pulses by direct current modulation of semiconductor lasers and chirp-to-intensity conversion

“…The same group also obtained UWB pulses by synthesizing a bandpass coherent microwave filter by combining an electro-optic phase modulator (EOPM) with fiber dispersion [6], acting globally as an electronic differentiator at low frequencies but implemented in the optical domain. More recently, some reported optical UWB signal generation approaches take advantage of the nonlinear optical properties of semiconductor optical amplifiers (SOAs) [7][8][9]. By exploiting cross-gain modulation [7], the output light of the SOA consisted of two reversed polarized pulses.…”