Ultra-wideband doublet signal generation with tunable notch band based on delay-line filter

ABSTRACT

A novel and simple scheme to generate Ultra-wideband (UWB) doublet signal with tunable notch band based on a tunable delay-line filter is presented. The first-order differentiation is realized by a dual-drive Mach–Zehnder modulator (DD-MZM), which differentiates the Gaussian pulses to the monocycle pulses. Subsequently, the UWB monocycle pulses are transmitted to an optical delay-line filter implemented by a balanced photo-detector and a tunable delay line for both differentiation and photodetection. Consequently, the desired UWB doublet signal can be obtained with a 10-dB bandwidth of 8.75 GHz. Besides, the polarity reversibility of the generated doublet signal is demonstrated by changing the bias voltage of the DD-MZM. Moreover, the desired notch can be introduced in the generated frequency spectrum to eliminate the interference between the existing narrowband systems and the UWB systems. And the tunability of the band-notched position is implemented by simply adjusting the delay time of the delay-line filter. The feasibility of the presented scheme is investigated by mathematical models and simulations.

KEYWORDS:

• Ultra-wideband
• delay-line filter
• notch band
• phase modulation intensity modulation conversion

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant number 61875070], the Department of Science and Technology of Jilin Province [grant numbers 20160519010JH, 20170204006GX, 20180201032GX], and the Science and Technology Project of Education Department of Jilin Province [grant number JJKH20190110KJ].

Notes on contributors

Cong Du

Cong Du is working toward her PhD at the College of Electronic Science and Engineering, Jilin University. Her main research interest is microwave photonic ultra-wideband communication system.

Fangming Liu

Fangming Liu is pursuing her master’s degree at the College of Electronic Science and Engineering, Jilin University. Her main research interest is microwave photonic radar signal processing.

Yujiao Ding

Yujiao Ding will receive her master’s degree at the College of Electronic Science and Engineering, Jilin University, in 2021. Her main research interest is microwave photonic filters.

Kai Wu

Kai Wu is working toward his bachelor’s degree at the College of Electronic Science and Engineering, Jilin University.

Baohua Li

Baohua Li is currently a full professor in the College of Electronic Science and Engineering, Jilin University. His research interest is applied electronic technology.

Wei Dong

Wei Dong received her PhD in microelectronics and solid-state electronics at Jilin University in 2004. Currently, she is a full professor in the College of Electronic Science and Engineering, Jilin University. Her research directions are microwave photonics and optical fiber sensing.