Dual Photonic Generation Ultrawideband Impulse Radio by Frequency Shifting in Remote-Connectivity Fiber

Abstract

A numerical study of the impact that manufacturing tolerances have on the performance of an InP 4 Â 4 MMI working as a 90 optical hybrid is presented, including simultaneous variations of width, thickness, and refractive index over the C and L bands. Simulation results for different figures of merit, such as optical common-mode rejection ratios (CMRRs) and phase errors, are provided for both nominal and worst case scenarios. Additionally, system simulations are performed to compute imbalance-induced power penalty. Our results indicate that the combined effect of realistic foundry tolerances on device performance is significant. In particular, a fourfold reduction is predicted between nominal ('40 nm) and worst cases ('10 nm) when optical CMRRs and phase errors are compared against Optical Internetworking Forum specifications. By contrast, a much greater bandwidth is expected at the system level (! 40 nm) if a power penalty of less than 1 dB ð@BER ¼ 10 À3 Þ is to be allowed. In fact, worst case power penalties lower than 0.25 dB are predicted over the full C band, which further proves the great potential of integrated 4 Â 4 MMIs as wide-bandwidth devices for mass production of coherent receivers using state-ofthe-art integration technologies.

Photonic Generation of Dual-Band Power-Efficient Millimeter-Wave UWB Signals

“…It is well known that the UWB signals are regulated by the Federal Communications Commission (FCC) of the United States in the frequency range of 3.1-10. 6 GHz band (i.e., baseband) and 22-29 GHz band (i.e., millimeter-wave band) for short-range communications and vehicular radar systems, respectively [1]. In addition, the operation of UWB signals in the 60 GHz millimeterwave band has also drawn some attention because it can easily provide high data rates up to several Gb/s in the currently unlicensed spectrum (e.g., 57-64 GHz in the United States and Canada).…”

“…However, few works have been dedicated to the generation of UWB signals in both of these two frequency bands considering dual-band operations. Very recently, a scheme to simultaneously generate UWB signals in 24 GHz and 60 GHz millimeter-wave bands has been proposed [1], which enables the flexible provision of several functionalities by one UWB system. However, the existing scheme requires a local oscillator and a MachZehnder modulator (MZM), which increases the system cost and complexity.…”

High-speed microwave photonic switch for millimeter-wave ultra-wideband signal generation

“…Since photonic generation of the baseband UWB signal has been extensively investigated, the most convenient method for MMW-UWB generation is to upconvert a baseband UWB signal to the MMW band [4][5][6]. The drawback of this technique is that a strong residual local oscillator (LO) always exists in the generated electrical spectrum, which would reduce the dynamic range of the receiver and limit emission levels if regulated [7].…”