Reconfigurable Instantaneous Frequency Measurement System Based on a Polarization Multiplexing Modulator

Abstract

We propose and demonstrate a new reconfigurable instantaneous frequency measurement (IFM) system based on a dual-polarization dual-drive Mach-Zehnder modulator (DPol-DMZM). By simply adjusting the dc biases on both arms of the DPol-DMZM, the upper and lower bounds of the IFM measurement range can be independently adjusted. Experiments have shown that the lower frequency bound is as low as 2 GHz, and the upper frequency bound is up to 23 GHz. The resolution of the three frequency measurement bandwidths of 5, 6.5, and 8 GHz is less than ±0.2 GHz. It is noted that the proposed IFM system is power dependent. To solve this problem, a power-independent scheme with a similar system structure based on a dual-polarization dual-parallel Mach-Zehnder modulator is proposed and theoretically analyzed.

Review of microwave frequency measurement circuits

“…In recent decades, with the development of high-speed ADC and the FPGA, the possibility of doing the instantaneous measurement without using analog discriminators is increasing but is still limited by the devices' clocks. The DMFM system identifies frequencies just until 5 GHz with a good resolution of 0.8 MHz [65]. The DMFM can provide a system with reconfigurable frequency and bandwidth and it also can estimate several different signal frequencies at the same time.…”

“…Finally, in the category of IFM receivers based on Photonics technology -MPMFM, various mathematical concepts and the Mach-Zehnder modulator (in most cases) are used to determine the frequency of a measured signal [34-38, 40-44, 65, 66]. The MPMFM have the advantages of broad frequency measurement range and bandwidth (1-52 GHz), low loss, lightweight, and immunity to electromagnetic interference compared to the planar techniques (up to 20 GHz) [65].…”

“…A reconfigurable instantaneous frequency measurement system based on a Dualpolarization Dual-drive Mach-Zehnder modulator (DPol-DMZM) was reported in 2019 [65]. By simply adjusting the DC biases on both arms of the DPol-DMZM, the upper and lower bounds of the IFM measurement range can be independently adjusted, defining the bandwidth.…”

Photonics-assisted microwave instantaneous frequency measurement based on frequency-power mapping

“…In the past decade, photonics IFM has received widespread attentions, and a large number of schemes have been designed [4]. The main methods of photonic assisted IFM include channelization, frequency-to-time mapping, frequencyto-power mapping, frequency-to-space mapping, compressed sensing, etc.…”

Photonic remote microwave frequency measurement with a tunable measurement range based on dispersion compensation technology

“…In general, to measure the frequency, a relationship between the microwave frequency and some specific parameters of the microwave photonic subsystem should be established, such as frequency-to-space mapping [5,6], frequency-to-time mapping [7,8], and frequency-to-power mapping [9][10][11][12][13]. It should be mentioned that these methods seldom considered the security of the receivers that are expensive and full-technology equipped.…”