阅读说明：本技术 采用双极化mzm调制器同时产生有线无线信号的装置及系统 (Device and system for simultaneously generating wired and wireless signals by adopting dual-polarization MZM modulator ) 是由 余建军 孔淼 于 2020-04-20 设计创作，主要内容包括：本发明涉及一种采用双极化MZM调制器同时产生有线无线信号的装置及系统,该装置用于产生包含QPSK信号I路数据、QPSK信号Q路数据和OOK数据信号的混合光信号,包括：毫米波载波发生模块,用于产生毫米波载波；I/Q混频器,用于产生QPSK毫米波信号；双极化MZM调制器,采用光副载波复用技术,同时产生QPSK调制格式的无线毫米波信号和OOK调制格式的有线基带信号,形成双边带光信号；光放大器,用于对双边带光信号进行放大；光滤波器,用于将放大后的双边带光信号转换为最终输出的混合光信号。与现有技术相比,本发明具有可靠性高、稳定性强、成本低廉、结构简单和易于实现等优点。(The invention relates to a device and a system for simultaneously generating wired and wireless signals by adopting a dual-polarization MZM modulator, wherein the device is used for generating a mixed optical signal containing QPSK signal I path data, QPSK signal Q path data and OOK data signals, and comprises the following components: the millimeter wave carrier generation module is used for generating millimeter wave carriers; an I/Q mixer for generating QPSK millimeter wave signals; the dual-polarization MZM modulator simultaneously generates a wireless millimeter wave signal in a QPSK modulation format and a wired baseband signal in an OOK modulation format by adopting an optical subcarrier multiplexing technology to form a dual-sideband optical signal; the optical amplifier is used for amplifying the double-sideband optical signal; and the optical filter is used for converting the amplified double-sideband optical signal into a finally output mixed optical signal. Compared with the prior art, the invention has the advantages of high reliability, strong stability, low cost, simple structure, easy realization and the like.)

1. An apparatus for simultaneously generating a wired wireless signal using a dual-polarized MZM modulator, the apparatus for generating a mixed optical signal including a QPSK signal I-path data, a QPSK signal Q-path data, and an OOK data signal, comprising:

the millimeter wave carrier generation module is used for generating millimeter wave carriers;

the I/Q mixer (7) is used for loading QPSK signal I path data and QPSK signal Q path data onto the millimeter wave carrier to generate a QPSK millimeter wave signal;

the dual-polarization MZM modulator (12) is driven by the QPSK millimeter wave signals and the OOK baseband electric signals, adopts an optical subcarrier multiplexing technology, and simultaneously generates wireless millimeter wave signals in a QPSK modulation format and wired baseband signals in an OOK modulation format to form dual-sideband optical signals;

an optical amplifier (13) for amplifying the dual sideband optical signal;

and the optical filter (14) is used for converting the amplified double-sideband optical signal into a finally output mixed optical signal.

2. The device for simultaneous generation of wired and wireless signals using a dual-polarized MZM modulator according to claim 1, wherein said millimeter wave carrier generation module comprises a sine generator (5) and a frequency multiplier (6) connected to each other.

3. The apparatus for simultaneously generating wired and wireless signals using a dual-polarized MZM modulator according to claim 1, wherein said QPSK millimeter wave signal and OOK baseband electrical signal are amplified by electrical amplifiers (8, 10) and transmitted to said dual-polarized MZM modulator (12).

4. The apparatus for simultaneous generation of wired wireless signals using a dual polarized MZM modulator of claim 1, characterized in that the data source of said dual polarized MZM modulator (12) is a distributed feedback laser (11).

5. The apparatus for simultaneous generation of a wired wireless signal using a dual-polarized MZM modulator of claim 1, wherein said dual-polarized MZM modulator (12) comprises two PSK modulators, one polarization beam splitter and one polarization beam coupler.

6. The device for simultaneously generating wired and wireless signals using a dual-polarized MZM modulator of claim 1, wherein said dual-polarized MZM modulator (12) modulates QPSK millimeter wave signals and OOK baseband electrical signals onto an original optical carrier and an optical millimeter wave sub-carrier separated from said original optical carrier by a set frequency, respectively, said original optical carrier having a frequency f_cThe frequency of the original optical carrier being (f)_c-f_R，f_c+f_R)，f_RIs the frequency of the millimeter wave carrier wave.

7. The apparatus for simultaneously generating a wired wireless signal using a dual-polarized MZM modulator of claim 1, wherein the dual-polarized MZM modulator (12) generates dual-sideband optical signals in which the wireless millimeter-wave signal and the wired baseband signal are in mutually orthogonal polarization directions.

8. The device for simultaneous generation of wired wireless signals using a dual polarized MZM modulator according to claim 1, wherein said mixed optical signal is transmitted through a single mode optical fiber (15).

9. A communication system comprising a central station (1) and a base station (2) connected, said central station (1) being an apparatus for simultaneously generating wired radio signals using a dual-polarized MZM modulator as claimed in claim 1.

10. The communication system according to claim 9, wherein the base station (2) comprises:

a photodiode (16) for converting the mixed optical signal into a baseband signal and a millimeter wave electrical signal;

a millimeter wave transmitting antenna (18) for transmitting a millimeter wave electric signal;

a baseband receiver (17) for receiving and processing the baseband signal.

Technical Field

The invention belongs to the technical field of photo-generated millimeter waves, relates to a communication system based on Radio-over-Fiber (RoF), and particularly relates to a device and a system for simultaneously generating wired wireless signals by adopting a dual-polarization MZM modulator.

Background

In recent years, with the rapid development of internet technology, various new services and new technologies have led to a rapid increase in data traffic, and the demand for the scale of bandwidth and capacity of communication networks has been increasing. The communication frequency band of mobile communication and space communication moves to the millimeter wave frequency band with higher frequency, and the frequency band can support larger transmission bandwidth and speed, thereby providing larger system capacity. However, it has been difficult to generate high-quality millimeter wave signals based on the electric domain technology. Advanced photon technology can generate high-frequency microwave millimeter wave signals, breaks through the influence of electronic bandwidth bottleneck, has large adjustable frequency range and extremely low phase noise, and can realize seamless butt joint with an optical communication network. In order to fully utilize the huge bandwidth of the optical fiber and the flexibility of wireless communication, the RoF system in which a wireless network and an optical network are converged becomes a potential solution to satisfy both large capacity and mobility.

Next generation access networks are promoting the convergence of wired and wireless dual services, providing more ultra-high bandwidth service options to end users in a cost-effective manner. In some conventional convergence schemes for wired and wireless services, cascaded modulators are used to generate baseband and rf signals simultaneously, which increases the complexity and instability of the system while increasing the cost, and thus is not suitable for the development of future high-speed wireless systems. The generation and transmission of high-speed wired and wireless signals with a simple, low-cost, and reliable configuration is critical to successful deployment in practical networks.

A scheme using a single two-arm Mach-Zehnder Modulator (abbreviated MZM) while generating independent wired and wireless binary open key control (abbreviated OOK) signals is proposed in the document "simultaneousness generation of independent wired and wireless services using antenna-wave-band radio-over-fiber systems" (z.jia, j.yu, a.chowdhury, g.ellimas, and g. -k.chang, IEEE photonics technology Letters, vol.19, No.20, pp.1691-1693,2007), thereby achieving ultra high speed dual services using lower cost. However, the problem of mutual interference between wired and wireless signals still exists, and the optical fiber dispersion is influenced by the dispersion walk-off effect of the optical fiber caused by the double side bands, so that the transmission distance of the optical fiber is limited, certain power loss is caused, and the reliability of the system is influenced.

Disclosure of Invention

The present invention is directed to overcome the above-mentioned drawbacks of the prior art, and provides an apparatus and a system for simultaneously generating wired and wireless signals by using a dual-polarized MZM modulator, which can implement high-speed wired and wireless dual services with simplicity and low cost, and have high reliability.

The purpose of the invention can be realized by the following technical scheme:

an apparatus for simultaneously generating a wired wireless signal using a dual-polarized MZM modulator, the apparatus for generating a mixed optical signal including QPSK signal I-path data, QPSK signal Q-path data, and OOK data signals, comprising:

the millimeter wave carrier generation module is used for generating millimeter wave carriers;

the I/Q mixer is used for loading QPSK signal I path data and QPSK signal Q path data onto the millimeter wave carrier to generate a QPSK millimeter wave signal;

the dual-polarization MZM modulator is driven by the QPSK millimeter wave signal and the OOK baseband electric signal, adopts an optical subcarrier multiplexing technology, and simultaneously generates a wireless millimeter wave signal in a QPSK modulation format and a wired baseband signal in an OOK modulation format to form a dual-sideband optical signal;

the optical amplifier is used for amplifying the double-sideband optical signal;

and the optical filter is used for converting the amplified double-sideband optical signal into a finally output mixed optical signal.

Further, the millimeter wave carrier generation module comprises a sine generator and a frequency multiplier which are connected.

Further, the QPSK millimeter wave signal and the OOK baseband electric signal are amplified by an electric amplifier and then transmitted to the dual-polarization MZM modulator.

Further, the data source of the dual-polarized MZM modulator is a distributed feedback laser.

Further, the dual-polarized MZM modulator includes two PSK modulators, one polarization beam splitter, and one polarization beam coupler.

Further, the dual-polarization MZM modulator modulates a QPSK millimeter wave signal and an OOK baseband electric signal on an original optical carrier and an optical millimeter wave subcarrier which is away from the original optical carrier by a set frequency respectively, wherein the frequency of the original optical carrier is f_cThe frequency of the original optical carrier is f_RIs the frequency of the millimeter wave carrier wave.

Further, in the dual-sideband optical signal generated by the dual-polarized MZM modulator, the wireless millimeter wave signal and the wired baseband signal are in mutually orthogonal polarization directions.

Further, the mixed optical signal is transmitted through a single mode optical fiber.

The invention also provides a communication system which comprises a central station and a base station which are connected, wherein the central station is a device which adopts the dual-polarization MZM modulator to simultaneously generate wired wireless signals.

Further, the base station includes:

a photodiode for converting the mixed optical signal into a baseband signal and a millimeter wave electrical signal;

the millimeter wave transmitting antenna is used for transmitting millimeter wave electric signals;

a baseband receiver for receiving and processing baseband signals.

Compared with the prior art, the invention has the following beneficial effects:

1) the invention adopts the optical subcarrier multiplexing technology, utilizes a dual-polarization MZM modulator to simultaneously generate a wireless millimeter wave signal in a QPSK modulation format and a wired baseband signal in an OOK modulation format, realizes that the two signals are simultaneously transmitted on the same wavelength through optical fibers, and simultaneously provides independent wired and wireless services for different users in an economical and efficient manner; the QPSK modulation format is also applied to the dual service of wired and wireless signals for the first time.

2) The invention utilizes the dual-polarization MZM modulator to modulate two signals in the polarization directions which are mutually orthogonal, thereby avoiding the mutual interference of the two signals in the photodiode and ensuring the high-quality wired and wireless service.

3) The invention changes the original double-sideband signal into the single-sideband signal, thereby avoiding the optical fiber dispersion walk-off effect caused by two sidebands, and the optical signal transmitted by the optical fiber does not need dispersion compensation, thereby realizing the reliable transmission on the optical fiber with a certain length.

4) The invention provides wired and wireless dual services with higher reliability by using a RoF system with lower cost and simple structure.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic diagram of a user mobile terminal;

FIG. 3 is a spectrum of an optical signal in an embodiment of the present invention;

in the figure, 1-central station, 2-base station, 3-QPSK signal I data, 4-QPSK signal Q data, 5-sine wave generator, 6-frequency multiplier, 7-I/Q mixer, 8-electrical amplifier, 9-OOK data signal, 10-electrical amplifier, 11-distributed feedback laser, 12-dual polarization MZM modulator, 13-optical amplifier, 14-optical filter, 15-single mode fiber, 16-photodiode, 17-baseband receiver, 18-millimeter wave transmitting antenna, 19-millimeter wave receiving antenna, 20-sine wave generator, 21-frequency multiplier, 22-mixer, 23-baseband receiver.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.