A New Scheme to Generate Multi-Frequency Mm-Wave Signals Based on Cascaded Phase Modulator and I/Q Modulator

Abstract

We propose a new scheme to generate multi-frequency vector mm-wave signals based on cascaded phase modulator and I/Q modulator by adopting independent-sideband (ISB) modulation scheme. Driven by a single frequency RF (Radio frequency) source, the phase modulator (PM) generates multi-frequency optical carriers with a constant frequency interval, which is used as optical input of the I/Q modulator. The electrical signal driving the I/Q modulator is composed of one vector-modulated single side-band (SSB) QAM signal and one unmodulated SSB RF signal, the two signals locate at different sides of zero frequency. The output of I/Q modulator contains several multi-frequencies optical sidebands and suppressed optical carriers. The optical carriers are suppressed by using the ISB modulation scheme. Two optical sidebands at different frequencies are selected by a wavelength select switch (WSS) and beaten in the photodetector (PD). The multi-frequency vector mm-wave signals are generated with high flexibility, and the frequency can be up to 400 GHz. We experimentally demonstrate 133-GHz D-band multi-frequency vector mmwave signal over 80-km SMF-28 wireline transmission and 10-m wireless delivery with bit rate up 18.4 × 2 = 36.8 Gb/s.

Demodulation algorithm for optical fiber fabry-perot interference sensor

“…Otherwise, the cavity length calculated by FFT will have a deviation, leading to lower resolution. PhD Zhou Xinlei demodulates the spectral signal using cubic spline interpolation and Gaussian interpolation [23], and the resolution has increased by one time, reaching to 7nm, as shown Fig. 1.…”

“…The minimum mean square error estimation algorithm was first proposed by research group of prof. Yu Qingxu [23]. The algorithm evaluates the measured cavity length of extrinsic OFFPI sensor using mean square error, which is related to the parameter estimation theory.…”

“…Based on the research team results, in view of the problem that the minimum mean square error estimation demodulation algorithm may have "mode jump" when increasing the dynamic range, Zhou Xinlei proposed a vernier demodulation algorithm based on FFT and minimum mean square error estimation [23]. FFT is used to pre-position the FP cavity length, and then this pre-position is taken as the reference of the mean square error estimation range.…”

“…And also, extrinsic OFFPI sensors are divided into diaphragm-free type [5][6][7][8] and diaphragm type [13][14][15][16][17][18]. Various demodulation algorithms are then constantly proposed in view of resolution of sensors [20][21][22][23]. By demodulation of the interference spectrum signal, variation of cavity length can be calculated, and variation information of the parameter to be measured can be reversed.…”

V‐band vector mm‐wave signal generation enabled by a dual‐parallel Mach‐Zehnder modulator without precoding and optical filter

“…[5][6][7][8][9][10] Recently, some research groups proposed photonic schemes to generate vector mm-wave signal. [11][12][13][14][15][16][17][18][19] Remote heterodyne technology can bring the benefits of cost-effectiveness and easy implementation, which is ever considered as a very good candidate technology. However, because of unlocked frequency, the frequency of vector mm-wave generated by this scheme is not stable.…”