Multistage pulse amplitude modulator with function of achieving amplitude equalization of modulation signal

Abstract

The invention discloses a multistage pulse amplitude modulator with a function of achieving amplitude equalization of a modulation signal. The multistage pulse amplitude modulator comprises n Mach-Zahnder intensity modulators in series connection, wherein input ports and output ports of the Mach-Zahnder intensity modulators are connected end to end, and the input port of a first Mach-Zahnder intensity modulator is utilized as a light source input port, the output port of a final Mach-Zahnder intensity modulator is utilized as a modulation signal output port, and OOK signals with the same amplitude are loaded to each Mach-Zahnder intensity modulator, thereby achieving the modulation of 2N-stage pulse amplitude modulation signals; the effective modulation arm length ratio among the n Mach-Zahnder intensity modulators is 20 : 21: 22 : ... : 2N-1, and the arrangement sequence of the Mach-Zahnder intensity modulators with the above effective modulation arm length ratio does not limit to the above ratio sequence. According to the multistage pulse amplitude modulator with the function of achieving the amplitude equalization of the modulation signal, by improving the structure of the modulator, the flexible control of a phase bias point and the equalization of optical signals on the two arms of the modulator when the modulation signal is modulated are achieved, and the extinction ratio of the modulator is increased.

Description

technical field [0001] The invention relates to the field of optical communication devices, in particular to a multi-stage pulse amplitude modulator for realizing amplitude equalization of modulated signals. Background technique [0002] With the continuous progress and development of society, human beings have more and more demand for information, and the amount of information data in modern society has shown an exponential growth. The rapid development of optical communication network technology provides a reliable and effective solution to this problem. plan. The optical modulator is one of the core devices of the entire optical communication network, which is responsible for converting electrical signals into optical signals that can be transmitted in the optical communication network; traditional electro-optical high-speed modulators based on lithium niobate materials often have large dimensions, and in 5 On the order of -10 cm, the power consumption is also large, whi...

AI Technical Summary

Problems solved by technology

For a single Mach-Zehnder intensity modulator to realize the complex format modulation function, in addition to the high linearity and extinction ratio of the device itself, it is also required that the driving chip has a high output voltage swing and a high Linearity, which is very difficult to achieve for electronic chips

In order to improve the above shortcomings, a modulator structure driven by electrode segments is proposed. This modulator structure can be driven by multiple OOK signals to generate multi-level amplitude modulated optical signals, but the modulator structure driven by electrodes segment still shares a phase bias The controller has the disadvantage of inflexible phase control, and has relatively high requirements on the corresponding linearity of the electro-optic modulator; in addition, with the increase of the pulse amplitude order of the modulation signal, the length of a single device of the modulator structure driven by the above electrodes in segments will decrease larger, resulting in a lower overall extinction ratio

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