CN111416662B - Signal generation and transmission method based on polarization multiplexing double MZM modulator - Google Patents
Signal generation and transmission method based on polarization multiplexing double MZM modulator Download PDFInfo
- Publication number
- CN111416662B CN111416662B CN202010247673.2A CN202010247673A CN111416662B CN 111416662 B CN111416662 B CN 111416662B CN 202010247673 A CN202010247673 A CN 202010247673A CN 111416662 B CN111416662 B CN 111416662B
- Authority
- CN
- China
- Prior art keywords
- signal
- optical
- polarization
- mzm modulator
- modulator
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/50—Transmitters
- H04B10/516—Details of coding or modulation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J14/00—Optical multiplex systems
- H04J14/02—Wavelength-division multiplex systems
- H04J14/0201—Add-and-drop multiplexing
- H04J14/0202—Arrangements therefor
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J14/00—Optical multiplex systems
- H04J14/06—Polarisation multiplex systems
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Optical Communication System (AREA)
Abstract
The invention discloses a signal generation and transmission system and method based on a polarization multiplexing double MZM modulator, wherein the system comprises a central machine room end, a wired end and a mobile end; the central machine room end comprises a distributed feedback laser, a local oscillator, a polarization multiplexing modulator, a first code type converter and a second code type converter, wherein the polarization multiplexing modulator is integrated with a first MZM modulator, a second MZM modulator, a polarization beam splitter and a polarization beam combiner; the wired end comprises an optical filter, a first photoelectric detector, a second photoelectric detector, a first power amplifier, a second power amplifier, a transmitting antenna and a first signal processor; the mobile terminal comprises a receiving antenna, a third power amplifier and a second signal processor. The system has reasonable structure, can be effectively applied to high-capacity wired and wireless mixed transmission communication, has good use effect and is convenient to popularize and use.
Description
Technical Field
The invention belongs to the technical field of communication, and particularly relates to a signal generation and transmission method based on a polarization multiplexing dual MZM modulator.
Background
With the rapid increase of communication services of big data, cloud computing, artificial intelligence, internet of things and mobile internet, the existing optical access network is difficult to meet the requirements of multifunctional, high-capacity wired and wireless hybrid transmission in the future, and the development of a new generation of high-speed, broadband wired and wireless hybrid communication access network technology becomes an urgent requirement at present. The light and wireless integration communication technology combines the broadband wireless transmission of millimeter waves and the high-capacity transmission characteristics of optical fibers, not only can effectively overcome the bandwidth bottleneck problem of electronic devices, but also can improve the transmission rate of wireless signals in multiples. The optical and wireless integrated communication system can simultaneously generate and transmit wired and wireless signals, and has wide application prospect in access network systems such as fiber-to-the-home, fiber-to-the-office, fiber-to-the-building and the like.
In the prior art, the schemes of the wired signal and wireless signal hybrid transmission access system mainly include the following two types:
1. based on the wired signal and wireless signal mixed transmission scheme of the wavelength division multiplexing device, at the transmitting end, optical transmitters of different signal types can be accessed to the wavelength division multiplexer, wherein the modulation mode and the type of the transmitters are not limited, and the modulated carrier signals sent by the transmitters are transmitted to the input end of the wavelength division multiplexer by using optical fibers. The optical wavelength division multiplexer is a multi-input single-output device, each input port corresponds to a specific wavelength input, and all input optical signals are multiplexed to an optical fiber by the optical wavelength division multiplexer for transmission. At the receiving end, a device identical to the optical wavelength division multiplexer is used in reverse connection, which is generally called as an optical wave decomposition multiplexer, the optical wave decomposition multiplexer can output signals with different wavelengths obtained from the transmission optical fiber from corresponding ports to complete optical signal demultiplexing, the optical signals of the receiving end separated by the optical wave decomposition multiplexer respectively enter corresponding receivers, and each receiver completes demodulation of the optical signals according to a corresponding modulation protocol, so that the original signals can be recovered. The multiple signal mixing transmission system based on the optical wavelength division multiplexer can realize the simultaneous transmission of a plurality of signals or a plurality of signals, the type or the number of the transmitted signals only depends on the number of input and output ports of the optical wavelength division multiplexer, the generation and the receiving devices of the various signals are mutually independent, and each signal occupies one channel (wavelength). However, each channel or each transmitter cannot simultaneously generate a mixed signal (wireless signal and wired signal), and in this way, the transmission capacity is increased depending on the number of transmitters and receivers, the number of signal generation is proportional to the number of used devices, and thus the system cost is high, and this structure is generally rarely used in an access network system.
2. The mixed signal transmission scheme based on the MZM includes a system for simultaneously generating and transmitting a wired and wireless mixed signal based on a single MZM (Mach-Zehnder Modulator) and a system for simultaneously generating and transmitting a wired and wireless mixed signal based on a dual MZM. In a system of a single MZM for simultaneously generating and transmitting wired and wireless hybrid systems, wired data and wireless data can be respectively modulated to two arms of the MZM, or the two data can be modulated to one arm of the MZM after being mixed, and the system can perform vector signal transmission or non-vector signal transmission; the system based on the double MZMs for simultaneously generating and transmitting the wired and wireless mixed signals is integrated on a module, wired data and wireless data can be respectively modulated to each MZM, the two kinds of data can be mixed and then modulated to one MZM, the system can perform vector signal transmission and non-vector signal transmission, whether a single MZM scheme or two MZM schemes are adopted, wired data is generally modulated to a central carrier wave emitted by a light source, and wireless data is modulated to the MZM to generate optical sideband signals. At the receiving end, it is first necessary to separate the two signals by using an optical filter, and then demodulate the corresponding transmission signals by using optical receivers, so as to recover the original signals. The two wired and wireless mixed signal generating and transmitting systems have the advantages of simple structure and low cost, and are very suitable for application scenes of fiber to the home, fiber to the office, fiber to a building and the like. However, since the modulators used are limited by electronic bandwidth limitations, as the modulation rate increases, the signal-to-noise ratio of the modulated optical carrier signal decreases dramatically, thus having limited potential for further increasing the transmission rate. In addition, in order to reduce the mutual interference between the wired data and the wireless data during the generation and transmission processes and improve the signal-to-noise ratio of the channel, a high-performance optical filter is required at the receiving end, which is not favorable for reducing the system cost.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a signal generation and transmission system based on polarization multiplexing dual MZM modulator, which has the advantages of reasonable structural design, convenient implementation, effective application in high-capacity wired and wireless hybrid transmission communication, reduced construction cost of the signal generation and transmission system, high efficiency and stability of signal transmission, good use effect, and convenient popularization and use.
In order to solve the technical problems, the invention adopts the technical scheme that: a signal generation and transmission system based on a polarization multiplexing double MZM modulator comprises a central machine room end, a wired end and a mobile end, wherein the central machine room end simultaneously generates wired signals and wireless signals, the wired end performs wired transmission with the central machine room end, and the mobile end performs wireless transmission with the wired end; the central machine room end comprises a distributed feedback laser, a local oscillator, a polarization multiplexing modulator, a first code type converter and a second code type converter, wherein the first code type converter is used for converting a wireless data signal into a baseband electric signal, and the second code type converter is used for converting a wired data signal into the baseband electric signal; the polarization multiplexing modulator is integrated with a first MZM modulator, a second MZM modulator, a polarization beam splitter and a polarization beam combiner, the first MZM modulator and the second MZM modulator are both connected with the output end of the polarization beam splitter, the first MZM modulator and the second MZM modulator are both connected with the input end of the polarization beam combiner, the output end of the distributed feedback laser is connected with a polarization controller, the polarization beam splitter is connected with the output end of the polarization controller, the output end of the local oscillator is connected with a frequency multiplier, the output end of the frequency multiplier is connected with a frequency mixer, the first code type converter is connected with the input end of the frequency mixer, the output end of the frequency mixer is connected with a first radio frequency amplifier, the first MZM modulator is connected with the output end of the first radio frequency amplifier, the output end of the second code type converter is connected with a second radio frequency amplifier, the second MZM modulator is connected with the output end of a second radio frequency amplifier, the input end of the first MZM modulator is connected with a first direct current bias power supply, the input end of the second MZM modulator is connected with a second direct current bias power supply, and the output end of the polarization beam combiner is connected with an optical fiber amplifier; the wired end comprises an optical filter, the optical filter is connected with the output end of the optical fiber amplifier, the output end of the optical filter is connected with a first photoelectric detector and a second photoelectric detector, the output end of the first photoelectric detector is connected with a first power amplifier, the output end of the first power amplifier is connected with a transmitting antenna, the output end of the second photoelectric detector is connected with a second power amplifier, and the output end of the second power amplifier is connected with a first signal processor; the mobile terminal comprises a receiving antenna used for receiving wireless signals transmitted by the transmitting antenna, the output end of the receiving antenna is connected with a third power amplifier, and the output end of the third power amplifier is connected with a second signal processor.
In the signal generation and transmission system based on the polarization multiplexing dual MZM modulator, the fiber amplifier is a polarization maintaining erbium-doped fiber amplifier.
In the signal generation and transmission system based on the polarization multiplexing dual MZM modulator, the polarization beam splitter and the first MZM modulator, the polarization beam splitter and the second MZM modulator, the first MZM modulator and the polarization beam combiner, and the second MZM modulator and the polarization beam combiner are connected by the polarization maintaining single mode fiber.
In the signal generation and transmission system based on the polarization multiplexing dual MZM modulator, the distributed feedback laser and the polarization controller, the polarization controller and the polarization beam splitter, the polarization beam combiner and the optical fiber amplifier, and the optical fiber amplifier and the optical filter are connected by the single mode fiber.
In the signal generation and transmission system based on the polarization multiplexing dual MZM modulator, the transmitting antenna and the receiving antenna are both cassegrain antennas.
The invention also discloses a signal generation and transmission method based on the polarization multiplexing double MZM modulator, which comprises the following steps:
step one, the emission frequency of the distributed feedback laser is fcAfter the polarization controller controls the polarization of the optical signal, the optical signal is incident into the polarization multiplexing modulator;
step two, a polarization beam splitter in the polarization multiplexing modulator separates the polarization state of optical signals, the two separated optical signals are respectively incident into a first MZM modulator and a second MZM modulator, a first direct current bias power supply biases the first MZM modulator at a minimum transmission point, and a second direct current bias power supply biases the second MZM modulator at an orthogonal point;
step three, the first code converter converts the wireless data signal to be transmitted into a baseband electric signal, and the baseband electric signal is transmitted into a mixer through a high-frequency coaxial cable; at the same time, the local oscillator generates a frequency fsSine or cosine radio frequency ofThe radio frequency signal is boosted by integral multiple to be nf by the action of the frequency multipliersThen, the signal is transmitted to a mixer through a high-frequency coaxial cable and is mixed with a baseband electric signal to obtain a radio-frequency electric signal;
amplifying the radio-frequency electric signal by the first radio-frequency amplifier, driving a first MZM modulator by the amplified radio-frequency electric signal, carrying out carrier suppression on the amplified radio-frequency electric signal by the first MZM modulator to generate an optical millimeter wave signal for transmitting a wireless signal, and transmitting the optical millimeter wave signal to a polarization optical beam combiner;
fifthly, the second code converter converts the wired data signal to be transmitted into a baseband electric signal, the baseband electric signal is transmitted to a second radio frequency amplifier through a high-frequency coaxial cable to be amplified, the amplified baseband electric signal directly drives a second MZM modulator to generate an optical carrier signal, and the optical carrier signal is transmitted to a polarized light beam combiner;
coupling the optical millimeter wave signal and the optical carrier signal into the same optical fiber by the polarization beam combiner, amplifying the coupled optical signal by an optical fiber amplifier, and transmitting the amplified coupled optical signal to an optical filter through a single-mode optical fiber;
seventhly, the optical filter at the wired end separates the coupled optical signals carrying different data, wherein the separated optical millimeter wave signals are incident into a first photoelectric detector to generate electric millimeter wave signals, and the electric millimeter wave signals are amplified by a first power amplifier, converted into wireless electric millimeter wave signals by a transmitting antenna and sent to a space; meanwhile, the separated optical carrier signal passes through a second photoelectric detector and a second power amplifier in sequence, and then is subjected to signal processing by a first signal processor to recover a wired data signal;
and step eight, the receiving antenna of the mobile terminal receives the wireless electric millimeter wave signals in the space, and the received electric millimeter wave signals are amplified through a third power amplifier and then subjected to signal processing through a second signal processor to recover the wireless data signals.
Compared with the prior art, the invention has the following advantages:
1. the system of the invention has reasonable structural design and convenient realization.
2. The polarization multiplexing modulator is adopted to replace the existing single MZM modulator or double MZM modulator, the second MZM modulator is utilized to modulate a wired signal onto a central optical carrier, and the optical millimeter wave signal generated by the first MZM modulator is utilized to realize the transmission of a wireless signal; in addition, because the polarization directions of the two optical signals are orthogonal to each other, at the receiving end, the performance requirement of the optical filter for separating the two optical signals is not high, and even if the optical filter cannot completely separate the two signals, the receiving of the signals is not influenced, so that the channel has a higher signal-to-noise ratio, and the construction cost of the system is further reduced.
3. The invention can be effectively applied to high-capacity wired and wireless mixed transmission communication, reduces the construction cost of a signal generation and transmission system, has high and stable signal transmission and good use effect, and is convenient to popularize and use.
In conclusion, the system of the invention has reasonable structural design and convenient realization, can be effectively applied to high-capacity wired and wireless mixed transmission communication, reduces the construction cost of a signal generation and transmission system, has high and stable signal transmission and good use effect, and is convenient for popularization and use.
The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.
Drawings
FIG. 1 is a schematic block diagram of the system architecture of the present invention;
fig. 2 is a bit error rate curve of a wireless signal and a wired signal under different incident optical power of an optical carrier according to the present invention.
Description of reference numerals:
1-distributed feedback laser; 2-a local oscillator; 3-a polarization multiplexing modulator;
3-1 — a first MZM modulator; 3-2 — a second MZM modulator; 3-a polarizing beam splitter;
3-4-a polarized beam combiner; 4-a first pattern transformer; 5-a second pattern transformer;
6-a polarization controller; 7-a frequency multiplier; 8-a mixer;
9-a first radio frequency amplifier; 10-a second radio frequency amplifier; 11-a first dc bias supply;
12-a second dc bias supply; 13-optical fiber amplifier; 14-an optical filter;
15 — a first photodetector; 16 — a second photodetector; 17 — a first power amplifier;
18-a transmitting antenna; 19-a second power amplifier; 20 — a first signal processor;
21-a receiving antenna; 22-a third power amplifier; 23-second signal processor.
Detailed Description
As shown in fig. 1, the signal generation and transmission system based on the polarization multiplexing dual MZM modulator of the present invention includes a central machine room end for simultaneously generating a wired signal and a wireless signal, a wired end for performing wired transmission with the central machine room end, and a mobile end for performing wireless transmission with the wired end; the central machine room end comprises a distributed feedback laser 1, a local oscillator 2, a polarization multiplexing modulator 3, a first code type converter 4 for converting a wireless data signal into a baseband electric signal and a second code type converter 5 for converting a wired data signal into the baseband electric signal; the polarization multiplexing modulator 3 is integrated with a first MZM modulator 3-1, a second MZM modulator 3-2, a polarization beam splitter 3-3 and a polarization beam combiner 3-4, the first MZM modulator 3-1 and the second MZM modulator 3-2 are both connected with the output end of the polarization beam splitter 3-3, the first MZM modulator 3-1 and the second MZM modulator 3-2 are both connected with the input end of the polarization beam combiner 3-4, the output end of the distributed feedback laser 1 is connected with a polarization controller 6, the polarization beam splitter 3-3 is connected with the output end of the polarization controller 6, the output end of the local oscillator 2 is connected with a frequency multiplier 7, the output end of the frequency multiplier 7 is connected with a mixer 8, the first code pattern converter 4 is connected with the input end of the mixer 8, the output end of the mixer 8 is connected with a first radio frequency amplifier 9, the output end of the first MZM modulator 3-1 is connected with the output end of the first radio frequency amplifier 9, the output end of the second code converter 5 is connected with a second radio frequency amplifier 10, the output end of the second MZM modulator 3-2 is connected with the output end of the second radio frequency amplifier 10, the input end of the first MZM modulator 3-1 is connected with a first direct current bias power supply 11, the input end of the second MZM modulator 3-2 is connected with a second direct current bias power supply 12, and the output end of the polarization beam combiner 3-4 is connected with an optical fiber amplifier 13; the wired end comprises an optical filter 14, the optical filter 14 is connected with the output end of an optical fiber amplifier 13, the output end of the optical filter 14 is connected with a first photoelectric detector 15 and a second photoelectric detector 16, the output end of the first photoelectric detector 15 is connected with a first power amplifier 17, the output end of the first power amplifier 17 is connected with a transmitting antenna 18, the output end of the second photoelectric detector 16 is connected with a second power amplifier 19, and the output end of the second power amplifier 19 is connected with a first signal processor 20; the mobile terminal comprises a receiving antenna 21 for receiving the wireless signal transmitted by the transmitting antenna 18, the output end of the receiving antenna 21 is connected with a third power amplifier 22, and the output end of the third power amplifier 22 is connected with a second signal processor 23.
In this embodiment, the optical fiber amplifier 13 is a polarization maintaining erbium doped optical fiber amplifier.
In this embodiment, the polarization beam splitter 3-3 and the first MZM modulator 3-1, the polarization beam splitter 3-3 and the second MZM modulator 3-2, the first MZM modulator 3-1 and the polarization beam combiner 3-4, and the second MZM modulator 3-2 and the polarization beam combiner 3-4 are all connected by a polarization-maintaining single-mode fiber.
In specific implementation, the polarization direction of an optical signal is ensured to be unchanged in the transmission process among devices through the polarization-maintaining single-mode fiber.
In this embodiment, the distributed feedback laser 1 and the polarization controller 6, the polarization controller 6 and the polarization beam splitter 3-3, the polarization beam combiner 3-4 and the optical fiber amplifier 13, and the optical fiber amplifier 13 and the optical filter 14 are all connected by a single mode fiber.
In this embodiment, the transmitting antenna 18 and the receiving antenna 21 are both cassegrain antennas.
The invention discloses a signal generation and transmission method based on a polarization multiplexing dual MZM modulator, which comprises the following steps:
step one, the distributed feedback laser 1 emits light with the frequency fcAfter the polarization controller 6 controls the polarization of the optical signal, the optical signal is incident into the polarization multiplexing modulator 3;
in specific implementation, the polarization controller 6 can adjust the optical power of the two separated polarized lights.
Step two, a polarization beam splitter 3-3 in the polarization multiplexing modulator 3 separates the polarization state of the optical signal, the two separated optical signals are respectively incident to a first MZM modulator 3-1 and a second MZM modulator 3-2, the first direct current bias power supply 11 directly biases the first MZM modulator 3-1 at a minimum transmission point, and the second direct current bias power supply 12 directly biases the second MZM modulator 3-2 at an orthogonal point;
step three, the first code pattern converter 4 converts the wireless data signal to be transmitted into a baseband electric signal, and the baseband electric signal is transmitted to the mixer 8 through a high-frequency coaxial cable; at the same time, the local oscillator 2 generates a frequency fsThe radio frequency signal is boosted by integral multiple to nf by the action of the frequency multiplier 7sThen, the signal is transmitted to a mixer 8 through a high-frequency coaxial cable, and is mixed with a baseband electric signal to obtain a radio-frequency electric signal;
in specific implementation, the first code converter 4 converts a wireless data signal to be transmitted into a baseband electrical signal, where the electrical signal may be a vector signal or a non-vector signal.
Amplifying the radio frequency electric signal by the first radio frequency amplifier 9, driving the first MZM modulator 3-1 by the amplified radio frequency electric signal, carrying out carrier suppression on the amplified radio frequency electric signal by the first MZM modulator 3-1 to generate an optical millimeter wave signal for transmitting a wireless signal, and transmitting the optical millimeter wave signal to the polarization optical beam combiner 3-4;
in particular, since the first MZM modulator 3-1 is dc-biased at the minimum transmission point and thus operates in the carrier rejection mode, the central optical carrier is rejected at the optical output of the first MZM modulator 3-1, and a plurality of optical sideband signals are generated on both sides of the central optical carrier, on which optical sideband signals the wireless data is modulated, with a frequency separation of 2nfsThe pair of optical sideband signals are used as optical millimeter wave signals for transmitting wireless signals.
Fifthly, the second code converter 5 converts the wired data signal to be transmitted into a baseband electric signal, the baseband electric signal is transmitted to a second radio frequency amplifier 10 through a high-frequency coaxial cable to be amplified, the amplified baseband electric signal directly drives a second MZM modulator 3-2 to generate an optical carrier signal, and the optical carrier signal is transmitted to a polarization beam combiner 3-4;
in specific implementation, the second code converter 5 converts the wired data signal to be transmitted into a baseband electric signal, and the electric signal may be a vector signal or a non-vector signal; since the second MZM modulator 3-2 is biased at the quadrature point, the baseband electrical signal is modulated directly on the optical center carrier.
Sixthly, the polarized light beam combiner 3-4 couples the optical millimeter wave signal and the optical carrier signal into the same optical fiber, and the coupled optical signal is amplified by an optical fiber amplifier 13 and then transmitted to an optical filter 14 through a single mode optical fiber;
seventhly, the optical filter 14 at the wired end separates the coupled optical signals carrying different data, wherein the separated optical millimeter wave signals are incident into the first photoelectric detector 15 to generate electric millimeter wave signals, and the electric millimeter wave signals are amplified by the first power amplifier 17, converted into wireless electric millimeter wave signals by the transmitting antenna 18 and sent to a space; meanwhile, the separated optical carrier signal passes through the second photodetector 16 and the second power amplifier 19 in sequence, and then is subjected to signal processing by the first signal processor 20 to recover a wired data signal;
in specific implementation, the separated optical millimeter wave signal is incident to the first photodetector 15 with a bandwidth matching with the optical millimeter wave signal, and the first photodetector 15 generates heterodyne beat frequency for two first-order sideband signals (optical millimeter waves) according to the square detection law, so as to generate an electrical millimeter wave signal, wherein the frequency of the electrical millimeter wave signal is equal to the frequency difference of the two optical millimeter wave signals, that is, 2nfs。
Step eight, the receiving antenna 21 of the mobile terminal receives the wireless electric millimeter wave signal in the space, and after the received electric millimeter wave signal is amplified by the third power amplifier 22, the received electric millimeter wave signal is subjected to signal processing by the second signal processor 23 to recover the wireless data signal.
In order to verify the technical effect which can be generated by the invention, the experiment for simultaneously generating and transmitting 10Gbps wired signals and 4Gbps wireless signals is carried out on the signal generating and transmitting system based on the polarization multiplexing dual MZM modulator, the distributed feedback laser 1 emits 1551.07nm continuous lightwaves, the line width of the continuous lightwaves is less than 100kHz, the transmitting power is 10dBm, the half-wave voltage of the polarization multiplexing modulator 3 under 1GHz is about 3.5V, the 3dB bandwidth of the continuous lightwaves is 25GHz, the insertion loss is 6dB, the extinction ratio is 20dB, the local oscillator 2 generates a cosine signal with the frequency of 19.11GHz, the cosine signal is amplified to 38.22GHz through a frequency multiplier 7 which is 2 times, then the cosine signal is mixed with a wireless signal with the peak-to-peak voltage of 0.5V and the rate of 4Gbps in the mixer 8, the mixed signal is amplified by a first radio frequency amplifier 9 with the saturation output power of 30dBm and the frequency response range of 36-41 GHz, the generated carrier multiplexing signal directly drives a first MZM modulator 3-1 in the polarization multiplexing modulator 3, the first MZM modulator 3-1 is DC-biased at the minimum transmission point thereof by a first DC bias power supply 11, carrier suppression modulation is realized, a pair of optical sideband signals are generated, and the frequency interval of the sideband signals is 76.44 GHz; the other path of wired signal with peak-to-peak voltage of 0.5V and speed of 10Gbps is amplified by a second radio frequency amplifier 10 with saturation output power of 30dBm and frequency response range of 0-40 GHz, then a second MZM modulator 3-2 in the polarization multiplexing modulator 3 is directly driven, the second MZM modulator 3-2 is DC-biased on an orthogonal point by a second DC bias power supply 12, and therefore the wired signal is directly modulated on an optical carrier; the generated optical sideband signal and optical carrier signal are coupled into a single mode fiber by a polarization beam combiner 3-4, the power of the optical sideband signal and the optical carrier signal is boosted to 11dBm by an erbium-doped fiber amplifier, and then the optical sideband signal and the optical carrier signal are transmitted to a cable terminal through the single mode fiber.
At a wired end, an optical filter 14 with the resolution of 50/100GHz is used for separating optical carrier and optical sideband signals, the separated optical sideband signals enter a first photoelectric detector 15 with the 3dB bandwidth of 75GHz for heterodyne beat frequency, an electric millimeter wave signal of 76.44GHz is obtained, the electric millimeter wave signal is amplified by an electronic amplifier (a first power amplifier 17) of a W wave band (75-110 GHz), and then the electric millimeter wave signal is transmitted to a mobile end by a transmitting antenna 18; the other path of the optical carrier signal separated by the optical filter 14 directly enters a second photodetector 16 with a 3dB bandwidth of 15GHz for detection, and then the binary level signal can be recovered by using the decision circuit unit, so as to realize the transmission of the wired data signal.
In the mobile terminal, another cassegrain antenna (receiving antenna 21) which is the same as the transmitting antenna 18 is used for receiving the wireless millimeter wave signal, the received millimeter wave signal is amplified by a third power amplifier 22 with the frequency of 0-30 GHz and the power of 20dB again, then, a second signal processor 23 is used for completing envelope detection, and a binary level signal can be restored through a decision circuit unit, so that the transmission of the wireless data signal is realized.
As can be seen from fig. 2, both the wired signal and the wireless signal can achieve error-free rate transmission by increasing the transmission optical power.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all simple modifications, changes and equivalent structural changes made to the above embodiment according to the technical spirit of the present invention still fall within the protection scope of the technical solution of the present invention.
Claims (5)
1. A signal generation and transmission method based on a polarization multiplexing double MZM modulator comprises a central machine room end for simultaneously generating wired signals and wireless signals, a wired end for performing wired transmission with the central machine room end, and a mobile end for performing wireless transmission with the wired end; the central machine room end comprises a distributed feedback laser (1), a local oscillator (2) and a polarization multiplexing modulator (3), and a first code type converter (4) for converting a wireless data signal into a baseband electric signal and a second code type converter (5) for converting a wired data signal into the baseband electric signal; the polarization multiplexing modulator (3) is integrated with a first MZM modulator (3-1), a second MZM modulator (3-2), a polarization beam splitter (3-3) and a polarization beam combiner (3-4), the first MZM modulator (3-1) and the second MZM modulator (3-2) are both connected with the output end of the polarization beam splitter (3-3), the first MZM modulator (3-1) and the second MZM modulator (3-2) are both connected with the input end of the polarization beam combiner (3-4), the output end of the distributed feedback laser (1) is connected with a polarization controller (6), the polarization beam splitter (3-3) is connected with the output end of the polarization controller (6), the output end of the local oscillator (2) is connected with a frequency multiplier (7), and the output end of the frequency multiplier (7) is connected with a frequency mixer (8), the first code converter (4) is connected with the input end of a mixer (8), the output end of the mixer (8) is connected with a first radio frequency amplifier (9), the first MZM modulator (3-1) is connected with the output end of the first radio frequency amplifier (9), the output end of the second code converter (5) is connected with a second radio frequency amplifier (10), the second MZM modulator (3-2) is connected with the output end of the second radio frequency amplifier (10), the input end of the first MZM modulator (3-1) is connected with a first direct current bias power supply (11), the input end of the second MZM modulator (3-2) is connected with a second direct current bias power supply (12), and the output end of the polarization beam combiner (3-4) is connected with an optical fiber amplifier (13); the wired end comprises an optical filter (14), the optical filter (14) is connected with the output end of an optical fiber amplifier (13), the output end of the optical filter (14) is connected with a first photoelectric detector (15) and a second photoelectric detector (16), the output end of the first photoelectric detector (15) is connected with a first power amplifier (17), the output end of the first power amplifier (17) is connected with a transmitting antenna (18), the output end of the second photoelectric detector (16) is connected with a second power amplifier (19), and the output end of the second power amplifier (19) is connected with a first signal processor (20); the mobile terminal comprises a receiving antenna (21) for receiving the wireless signal transmitted by the transmitting antenna (18), the output end of the receiving antenna (21) is connected with a third power amplifier (22), the output end of the third power amplifier (22) is connected with a second signal processor (23), and the mobile terminal is characterized in that: the method comprises the following steps:
step one, the emission frequency of the distributed feedback laser (1) is fcAfter the polarization controller (6) controls the polarization of the optical signal, the optical signal is incident into the polarization multiplexing modulator (3);
step two, a polarization beam splitter (3-3) in the polarization multiplexing modulator (3) separates the polarization state of the optical signals, the two separated optical signals are respectively incident into a first MZM modulator (3-1) and a second MZM modulator (3-2), the first direct current bias power supply (11) biases the first MZM modulator (3-1) at a minimum transmission point in a direct current mode, and the second direct current bias power supply (12) biases the second MZM modulator (3-2) at an orthogonal point in a direct current mode;
step three, the first code converter (4) converts the wireless data signal to be transmitted into a baseband electric signal, and the baseband electric signal is transmitted into the mixer (8) through a high-frequency coaxial cable; at the same time, the local oscillator (2) generates a frequency fsThe radio frequency signal is boosted by integral multiple to be nf by the action of a frequency multiplier (7)sThen, the signal is transmitted to a mixer (8) through a high-frequency coaxial cable and is mixed with a baseband electric signal to obtain a radio-frequency electric signal;
amplifying the radio frequency electric signal by the first radio frequency amplifier (9), driving a first MZM modulator (3-1) by the amplified radio frequency electric signal, carrying out carrier suppression on the amplified radio frequency electric signal by the first MZM modulator (3-1) to generate an optical millimeter wave signal for transmitting a wireless signal, and transmitting the optical millimeter wave signal to a polarization optical beam combiner (3-4);
fifthly, the second code converter (5) converts the wired data signal to be transmitted into a baseband electric signal, the baseband electric signal is transmitted to a second radio frequency amplifier (10) through a high-frequency coaxial cable to be amplified, the amplified baseband electric signal directly drives a second MZM modulator (3-2) to generate an optical carrier signal, and the optical carrier signal is transmitted to a polarization optical beam combiner (3-4);
sixthly, the polarized light beam combiner (3-4) couples the optical millimeter wave signal and the optical carrier signal into the same optical fiber, and the coupled optical signal is amplified by an optical fiber amplifier (13) and then transmitted to an optical filter (14) through a single mode optical fiber;
seventhly, the optical filter (14) at the wired end separates the coupled optical signals carrying different data, wherein the separated optical millimeter wave signals are incident into a first photoelectric detector (15) to generate electric millimeter wave signals, and the electric millimeter wave signals are amplified by a first power amplifier (17), converted into wireless electric millimeter wave signals by a transmitting antenna (18) and sent to a space; meanwhile, the separated optical carrier signals pass through a second photoelectric detector (16) and a second power amplifier (19) in sequence, and then are subjected to signal processing through a first signal processor (20) to recover wired data signals;
and step eight, the receiving antenna (21) of the mobile terminal receives wireless electric millimeter wave signals in the space, and the received electric millimeter wave signals are amplified through a third power amplifier (22) and then subjected to signal processing through a second signal processor (23) to recover wireless data signals.
2. The signal generation transmission method based on the polarization multiplexing dual MZM modulator of claim 1, wherein: the optical fiber amplifier (13) is a polarization-maintaining erbium-doped optical fiber amplifier.
3. The signal generation transmission method based on the polarization multiplexing dual MZM modulator of claim 1, wherein: the polarization beam splitter (3-3) and the first MZM modulator (3-1), the polarization beam splitter (3-3) and the second MZM modulator (3-2), the first MZM modulator (3-1) and the polarization beam combiner (3-4) and the second MZM modulator (3-2) and the polarization beam combiner (3-4) are connected through polarization-maintaining single-mode fibers.
4. The signal generation transmission method based on the polarization multiplexing dual MZM modulator of claim 1, wherein: the distributed feedback laser (1) is connected with the polarization controller (6), the polarization controller (6) is connected with the polarization beam splitter (3-3), the polarization beam combiner (3-4) is connected with the optical fiber amplifier (13), and the optical fiber amplifier (13) is connected with the optical filter (14) through single mode fibers.
5. The signal generation transmission method based on the polarization multiplexing dual MZM modulator of claim 1, wherein: the transmitting antenna (18) and the receiving antenna (21) are both Cassegrain antennas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010247673.2A CN111416662B (en) | 2020-03-31 | 2020-03-31 | Signal generation and transmission method based on polarization multiplexing double MZM modulator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010247673.2A CN111416662B (en) | 2020-03-31 | 2020-03-31 | Signal generation and transmission method based on polarization multiplexing double MZM modulator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111416662A CN111416662A (en) | 2020-07-14 |
| CN111416662B true CN111416662B (en) | 2021-06-25 |
Family
ID=71494726
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010247673.2A Active CN111416662B (en) | 2020-03-31 | 2020-03-31 | Signal generation and transmission method based on polarization multiplexing double MZM modulator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111416662B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112039597B (en) * | 2020-08-19 | 2021-05-28 | 西安电子科技大学 | Optical generation method and device for 16 frequency doubling millimeter wave signal |
| CN113098614B (en) * | 2021-03-12 | 2022-03-29 | 西安邮电大学 | Polarization multiplexing single sideband signal generating and receiving system and method |
| CN113890629B (en) * | 2021-10-20 | 2023-03-24 | 网络通信与安全紫金山实验室 | Terahertz signal receiving device and method and signal transmission system |
| CN117254859A (en) * | 2023-11-17 | 2023-12-19 | 鹏城实验室 | Coherent light transmission method and coherent light transmission system |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102629887A (en) * | 2012-05-09 | 2012-08-08 | 电子科技大学 | Full-duplex radio-over-fiber (RoF) access device |
| CN105721060A (en) * | 2016-01-13 | 2016-06-29 | 北京邮电大学 | Bidirectional multi-service access ROF transmission system and method for realizing carrier wave reuse by applying polarization multiplexing |
| CN107171732A (en) * | 2017-04-17 | 2017-09-15 | 西安电子科技大学 | A kind of microwave photon zero intermediate frequency reception device and method |
| CN208369590U (en) * | 2018-07-23 | 2019-01-11 | 华北水利水电大学 | Full duplex wire and wireless hybrid optical access system based on palarization multiplexing |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8867368B2 (en) * | 2012-09-05 | 2014-10-21 | Ciena Corporation | Systems and methods for noise tolerant signal processing in pilot assisted data receivers |
| EP2922221B1 (en) * | 2014-03-19 | 2018-08-29 | ZTE Corporation | Techniques for blind equalization of high-order quadrature amplitude modulation signals |
-
2020
- 2020-03-31 CN CN202010247673.2A patent/CN111416662B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102629887A (en) * | 2012-05-09 | 2012-08-08 | 电子科技大学 | Full-duplex radio-over-fiber (RoF) access device |
| CN105721060A (en) * | 2016-01-13 | 2016-06-29 | 北京邮电大学 | Bidirectional multi-service access ROF transmission system and method for realizing carrier wave reuse by applying polarization multiplexing |
| CN107171732A (en) * | 2017-04-17 | 2017-09-15 | 西安电子科技大学 | A kind of microwave photon zero intermediate frequency reception device and method |
| CN208369590U (en) * | 2018-07-23 | 2019-01-11 | 华北水利水电大学 | Full duplex wire and wireless hybrid optical access system based on palarization multiplexing |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111416662A (en) | 2020-07-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111416662B (en) | Signal generation and transmission method based on polarization multiplexing double MZM modulator | |
| CN112532325B (en) | Multi-dimensional multiplexing photon terahertz communication system | |
| US20110206383A1 (en) | Systems and methods for providing an optical information transmission system | |
| EP3130090B1 (en) | Radio-over-fibre transmission in communications networks | |
| CN104094538B (en) | For generation of the communicator with frequency discriminator and the correlation technique of intermediate-freuqncy signal | |
| CN110958053B (en) | Device and method for generating quad-frequency optical millimeter wave BPSK vector signal | |
| CN112039595B (en) | Optical carrier terahertz wave/millimeter wave generation system and method and transmitter | |
| US11984931B2 (en) | System for generating and receiving polarization multiplexed single sideband signal and method therefor | |
| CN111464240B (en) | Vector radio frequency signal generation system based on polarization multiplexing intensity modulator | |
| CN113765589A (en) | Terahertz wireless optical fiber expansion device and real-time transmission system thereof | |
| CN109581699B (en) | OOFDM signal-based low-cost low-polarization-sensitivity wide-tunable wavelength conversion device and method | |
| US10181909B2 (en) | Method and apparatus for optical wireless architecture | |
| US9621270B2 (en) | System and methods for fiber and wireless integration | |
| CN112929091A (en) | Multifunctional microwave photon radio frequency front-end system based on dual-polarization IQ modulator | |
| CN105680949A (en) | In-band full-duplex radio over fiber communication system based on wavelength division multiplexing | |
| CN101714899A (en) | Optical fiber radio communication system | |
| CN101001114A (en) | Full duplex fibre-optical radio communication system of simple structure | |
| CN111327364B (en) | System and method for generating vector signal by cascading intensity modulator and IQ modulator | |
| CN108718213B (en) | Full duplex wired and wireless hybrid optical access system and method based on polarization multiplexing | |
| CN108141284A (en) | The device and method that signal is handled in optical communication system | |
| CN108631881B (en) | Coherent light device | |
| US12021566B2 (en) | Photonics-aided vector terahertz signal communication system | |
| CN116015467A (en) | ODL-based M 2 QAM quadruple frequency millimeter wave signal generation and transmission system | |
| CN111555812B (en) | Device and system for simultaneously generating wired and wireless signals by adopting dual-polarization MZM modulator | |
| CN113740833A (en) | Microwave photon radar communication integrated system and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| EE01 | Entry into force of recordation of patent licensing contract | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20200714 Assignee: Xi'an Weiqin Network Technology Co.,Ltd. Assignor: XI'AN University OF POSTS & TELECOMMUNICATIONS Contract record no.: X2022980017945 Denomination of invention: Signal Generation and Transmission Method Based on Polarization Multiplexing Dual MZM Modulator Granted publication date: 20210625 License type: Common License Record date: 20221011 |