Photonics broadband microwave IQ modulator and operating method thereof

Abstract

The invention discloses a photonics broadband microwave IQ modulator and an operating method thereof. The method relates to the technical field of microwaves and the technical field of optical communication. The method is shown in an attached drawing, and comprises a laser diode (LD), a pulse duration modulation-dual parallel Mach-Zehnder modulator (PDM-DPMZM), an optical band pass filter (OBPF) and a photoelectric detector (PD). In the method, a pair of up-converters is constructed by the PDM-DPMZM and the OBPF, so that I-path and Q-path baseband waveforms can be directly modulated on a local oscillator (LO), and a broadband radiofrequency (RF) signal is obtained through the PD. The photonics broadband microwave IQ modulator has a simple structure; the bandwidth of an IQ baseband waveform is large; and the frequency of an LO signal can be tuned in a large range. A phase relationship between the two up-converters can be adjusted flexibly, so that the problem of IQ phase imbalance can be solved. Moreover, the RF signal generated by the IQ modulator has a large isolation degree on the LO, so that LO leakage can be restrained.

Description

technical field [0001] The invention relates to the field of microwave technology and the field of optical communication technology, and mainly relates to photonic broadband microwave IQ modulation technology. Background technique [0002] As people's requirements for communication speed are getting higher and higher, electronic systems such as radar and broadband wireless communication are now developing in the direction of large bandwidth and wide frequency band. In the traditional electronics-based microwave signal generation technology, there are speed bottlenecks in electronic devices, small instantaneous bandwidth, poor tuning of operating frequency, and serious electromagnetic interference. Photonics microwave signal generation technology has attracted a lot of attention due to its advantages such as large instantaneous bandwidth, wide operating frequency band, and anti-electromagnetic interference. [0003] At present, in the radio frequency transmitter of the elect...

AI Technical Summary

Problems solved by technology

This structure has the following disadvantages: (1) When the signal bandwidth is very large, the digital-to-analog converter is required to have a high sampling rate and operating frequency, and the current analog-to-digital conversion technology is gradually difficult to meet the needs; (2) when the radio frequency signal carries When the frequency is high, one or two stages of up-conversion are often required, and amplifiers and filters are generally required after each stage of frequency conversion, and the structure is complex; (3) The bandwidth of the traditional microwave mixer is small, and the passband tuning of the filter is poor, resulting in The reconfigurability of the transmitter frequency band is poor, which cannot meet the application requirements of multi-band integration in the future

However, the photonic IQ modulation technology of broadband microwave signals is rarely studied.

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