CN104185975A - 64qam signal generation method and system - Google Patents

64qam signal generation method and system Download PDF

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Publication number
CN104185975A
CN104185975A CN201380000294.1A CN201380000294A CN104185975A CN 104185975 A CN104185975 A CN 104185975A CN 201380000294 A CN201380000294 A CN 201380000294A CN 104185975 A CN104185975 A CN 104185975A
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signal
amplitude
level drive
signals
drive signal
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延双毅
吕超
刘伯涛
刘磊
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Huawei Technologies Co Ltd
Hong Kong Polytechnic University HKPU
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Huawei Technologies Co Ltd
Hong Kong Polytechnic University HKPU
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/32—Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
    • H04L27/34—Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
    • H04L27/36—Modulator circuits; Transmitter circuits
    • H04L27/362—Modulation using more than one carrier, e.g. with quadrature carriers, separately amplitude modulated

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Optical Communication System (AREA)
  • Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)

Abstract

The present invention provides a 64QAM signal generation method and system. The method comprises: a double-drive IQ modulator receiving input optical signals, dividing the input optical signals into a first input optical signal and a second input optical signal, inputting the first input optical signal into a first sub-modulator on an I-arm, and inputting the second input optical signal into a second sub-modulator on a Q-arm; the first sub-modulator receiving a first two-level drive signal and a first four-level drive signal, and based on the two signals, modulating the first input optical signal into a first 8-order amplitude phase modulating signal and outputting the first 8-order amplitude phase modulating signal; the second sub-modulator receiving a second two-level drive signal and a second four-level drive signal, and based on the two signals, modulating the second input optical signal into a second 8-order amplitude phase modulating signal and outputting the second 8-order amplitude phase modulating signal; and combining the first 8-order amplitude phase modulating signal and the second Q-arm 8-order amplitude phase modulating signal to generate a 64QAM signal. The implementing solution of the present invention is simple and has a low cost.

Description

64qam signal generation method and system
The present invention relates to the communication technology, more particularly to a kind of 64QAM signal creating methods and system for 64QAM signal creating methods and systems technology field.Background technology
With continuing to develop for information technology, internet traffic rapid growth, in order to tackle the huge transmission pressure that network traffics increase is brought, the transmission performance of core network system is also upgraded constantly, to improve the transmission capacity of existing network.Wherein, the more complicated modulation format of higher order is a kind of effective approach for improving transmission capacity, for example, in 64 quadrature amplitude modulations（Quadrature Amplitude Modulation, referred to as：QAM) in modulation format, the single bit information of symbol transmission 6, compared to the single bit information of symbol transmission 4 of 16QAM modulation formats, spectrum efficiency improves 0.5 times, with the higher availability of frequency spectrum, can further improve the transmission capacity of system.In the signal transmission system using above-mentioned 64QAM modulation formats, mainly by the electric signal after coding according to 64QAM signals (i.e. 64QAM planispheres）Form be modulated, generate 64QAM optical signals, then be transferred in optical fiber and be transmitted.Therefore, generation 64QAM optical signals are the keys for realizing 64QAM Transmission systems.
In the prior art, there is the optional mode of the following two kinds in the generating mode of 64QAM signals：A kind of mode is to drive single-ended I/Q modulator to generate 64QAM signals using 8 level signals, and the realization key of the program is the drive signal for producing 8 level；But, compared to 4 level signals or two more commonly used level signals, 8 level signals are higher for the performance requirement of electrical part；High-precision digital analog converter can for example be used by producing 8 level signals at present（Digital to analog converter, referred to as：) or AWG DAC（Arbitrary Wave Generator, referred to as：AWG), but both devices limit the popularization of its practical application due to its fancy price, mainly in the lab be used for scientific research.Another way is to produce 64QAM signals using the modulator of particular design, for example, by integrated multiple modulator electrodes in a traveling waveguide, being converted by complicated digital drive signals, produces 64QAM signals.But the modulator structure of the particular design used in this mode is complicated, cost is higher.To sum up, the technical sophistication and cost for being currently generated 64QAM signals are high.The content of the invention The present invention provides a kind of 64QAM signal creating methods and system, to reduce the manufacturing cost of 64QAM signals.
First aspect is there is provided a kind of 64QAM signal creating methods, and methods described is performed by the system including double drive IQ modulators, and double I/Q modulators of driving are used for the optical signal modulation of the input into the 64QAM signals；Double I/Q modulators of driving include setting the first sub- modulator on I arms and Q arms, the I arms, and the first sub- modulator includes the first driving electrical interface and the second driving electrical interface；Second sub- modulator is set on the Q arms, and the second sub- modulator includes the 3rd driving electrical interface and the 4th driving electrical interface；The 64QAM signal creating methods include：
Double I/Q modulators of driving receive the optical signal inputted, and the optical signal is divided into the first input optical signal and the second input optical signal, the described second sub- modulator on the described first sub- modulator on the first input optical signal input I arms, the second input optical signal input Q arms；
The first sub- modulator on the I arms, first liang of level drive signal is received by the described first driving electrical interface, one or four level drive signal is received by the described second driving electrical interface, and first input optical signal is modulated into by the one 8 rank amplitude phase modulation signal output based on first liang of level drive signal and the two or four level drive signal；
The second sub- modulator on the Q arms, second liang of level drive signal is received by the described 3rd driving electrical interface, two or four level drive signal is received by the described 4th driving electrical interface, and second input optical signal is modulated into by the 2nd 8 rank amplitude phase modulation signal output based on second liang of level drive signal and the two or four level drive signal；
Double I/Q modulators of driving merge by the one 8 rank amplitude phase modulation signal, with the rank amplitude phase modulation signal of the 2nd Q arms 8, generate 64QAM signals.
With reference to first aspect, in the first possible implementation, the phase difference between the second input optical signal that the described second sub- modulator on the first input optical signal and the Q arms that the described first sub- modulator on the I arms is received is received is 90 degree.
With reference to the first possible implementation of first aspect or first aspect, in second of possible implementation, one or four level drive signal is obtained by the different two level drive signals synthesis of two amplitudes, and two different level drive signals of described two amplitudes include：First low amplitude signal and the first high amplitude signals；Between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1:2:4;Two or four level drive signal is obtained by the different two level drive signals synthesis of two amplitudes , two different level drive signals of described two amplitudes include：Second low amplitude signal and the second high amplitude signals；Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4.
With reference to second of possible implementation of first aspect, in the third possible implementation, between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between the first low amplitude signal, first high amplitude signals and first liang of level drive signal is： 1 :2:4;Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between the second low amplitude signal, second high amplitude signals and second liang of level drive signal is： 1 :2:4.
With reference to second of possible implementation of first aspect, in the 4th kind of possible implementation, between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between the first low amplitude signal, first liang of level drive signal and first high amplitude signals is： 1 :2:4;Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between the second low amplitude signal, second liang of level drive signal and second high amplitude signals is： 1 :2:4.
With reference to second of possible implementation of first aspect, in the 5th kind of possible implementation, between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between first liang of level drive signal, the first low amplitude signal and first high amplitude signals is 1:2:4;Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between second liang of level drive signal, the second low amplitude signal and second high amplitude signals is 1:2:4.
With reference to any one into the 5th kind of possible implementation of the first possible implementation of first aspect or first aspect, in the 6th kind of possible implementation, the first driving electrical interface and the 3rd drives electrical interface to be positive pole electrical interface, and the second driving electrical interface and the 4th driving electrical interface are Negative pole electrical interface.
Second aspect there is provided a kind of 64QAM signal generating systems, including：First drive signal generating means, the second drive signal generating means, the 3rd drive signal generating means, fourth drive signal generating means and double drive I/Q modulators；Double I/Q modulator of driving is used for the optical signal modulation of the input into the 64QAM signals；Double I/Q modulators of driving include setting the first sub- modulator on I arms and Q arms, the I arms, and the first sub- modulator includes the first driving electrical interface and the second driving electrical interface；Second sub- modulator is set on the Q arms, and the second sub- modulator includes the 3rd driving electrical interface and the 4th driving electrical interface；Wherein,
The first drive signal generating means, for generating first liang of level drive signal；
The second drive signal generating means, for generating the one or four level drive signal；
The 3rd drive signal generating means, for generating second liang of level drive signal；
The fourth drive signal generating means, for generating the two or four level drive signal；
Double drive I/Q modulators, are used for：The optical signal of input is received, and the optical signal is divided into the second sub- modulator on the first sub- modulator on the first input optical signal and the second input optical signal, the first input optical signal input I arms, the second input optical signal input Q arms；The first sub- modulator on the I arms, first liang of level drive signal is received by the described first driving electrical interface, one or four level drive signal is received by the described second driving electrical interface, and first input optical signal is modulated into by the one 8 rank amplitude phase modulation signal output based on first liang of level drive signal and the two or four level drive signal；The second sub- modulator on the Q arms, it receives second liang of level drive signal by the described 3rd driving electrical interface, two or four level drive signal is received by the described 4th driving electrical interface, and second input optical signal is modulated into by the 2nd 8 rank amplitude phase modulation signal output based on second liang of level drive signal and the two or four level drive signal；
Double I/Q modulators of driving are additionally operable to merge by the one 8 rank amplitude phase modulation signal of the described first sub- modulator output, with the 2nd 8 rank amplitude phase modulation signal of the described second sub- modulator output, generate 64QAM signals.
With reference to second aspect, in the first possible implementation, the phase difference between the second input optical signal that the described second sub- modulator on the first input optical signal and the Q arms that the described first sub- modulator on the I arms is received is received is 90 degree.
With reference to the first possible implementation of second aspect or second aspect, in second of possible implementation, the second drive signal generating means, including： First signal generation sub-device, for generating the first low amplitude signal；
Secondary signal generates sub-device, and for generating the first high amplitude signals, the first low amplitude signal and the first high amplitude signals are two different level drive signals of two amplitudes；
Signal synthesizes sub-device, for being synthesized by two different level drive signals of described two amplitudes, obtains the one or four level drive signal；
Between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4;
The fourth drive signal generating means, including：
3rd signal generation sub-device, for generating the second low amplitude signal；
4th signal generation sub-device, for generating the second high amplitude signals, the second low amplitude signal and the second high amplitude signals are two different level drive signals of two amplitudes；
Signal synthesizes sub-device, for being synthesized by two different level drive signals of described two amplitudes, obtains the two or four level drive signal；
Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4.
With reference to second of possible implementation of second aspect, in the third possible implementation, between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between the first low amplitude signal, first high amplitude signals and first liang of level drive signal is： 1 :2:4;Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between the second low amplitude signal, second high amplitude signals and second liang of level drive signal is： 1 :2:4.
With reference to second of possible implementation of second aspect, in the 4th kind of possible implementation, between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between the first low amplitude signal, first liang of level drive signal and first high amplitude signals is： 1 :2:4;Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude between the second low amplitude signal, second liang of level drive signal and second high amplitude signals Ratio is： 1:2:4.
With reference to second of possible implementation of second aspect, in the 5th kind of possible implementation, between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1:2:4, including：Amplitude proportional between first liang of level drive signal, the first low amplitude signal and first high amplitude signals is 1:2:4;Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1:2:4, including：Amplitude proportional between second liang of level drive signal, the second low amplitude signal and second high amplitude signals is 1:2:4.
With reference to any one into the 5th kind of possible implementation of the first possible implementation of second aspect or second aspect, in the 6th kind of possible implementation, the first driving electrical interface and the 3rd drives electrical interface to be positive pole electrical interface, and the second driving electrical interface and the 4th driving electrical interface are negative pole electrical interfaces.
64QAM signal creating methods that the present invention is provided and system have the technical effect that：By respectively inputting two level drive signals and four level drive signals on the I arms and Q arms of double drive I/Q modulators, and the two drive signals meet the condition of amplitude proportional, then can generate 64QAM signals；This mode is due to two level drive signals and all fairly simple and easy generation of four level drive signals, and double to drive the product that I/Q modulator is also commercialization, it is achieved that project plan comparison is simple, and cost is low.Illustrate the structured flowchart that Fig. 1 is 64QAM signal transmission systems of the present invention；
Fig. 2 is the 64QAM planispheres that 64QAM signal transmission systems of the present invention are exported；
Fig. 3 is the double drive I/Q modulator structures and schematic diagram in the embodiment of 64QAM signal creating methods one of the present invention；
Fig. 4 is the schematic flow sheet of the embodiment of 64QAM signal creating methods one of the present invention；
Fig. 5 is the I arm output signal schematic diagrames in the embodiment of 64QAM signal creating methods one of the present invention；Fig. 6 is the Q arm output signal schematic diagrames in the embodiment of 64QAM signal creating methods one of the present invention；Fig. 7 is the 64QAM planispheres that export in the embodiment of 64QAM signal creating methods one of the present invention；Fig. 8 is the structural representation of the embodiment of 64QAM signal generating systems one of the present invention；
Fig. 9 is the structural representation of another embodiment of 64QAM signal generating systems of the present invention. Embodiment
64QAM signal transmitters are to be responsible for electric signal being modulated on light carrier in 64QAM signal transmission systems, may refer to Fig. 1, and Fig. 1 is the structured flowchart of 64QAM signal transmission systems of the present invention.In transmitting terminal, data generate multi-channel electric signal by precoding, the electric signal are modulated on light carrier by 64QAM emitters, generate 64QAM optical signals.Optical signal is received after optical fiber is transmitted in receiving terminal using coherent receiver, and is decoded, so as to recover the data sent before.
Wherein, the Primary Component of the signal transmission system is 64QAM emitters, electric signal is modulated on light carrier by it, is mainly used for converting electrical signals to the optical signal of the 64QAM modulation formats of transmission, the optical signal of the 64QAM modulation formats is 64QAM optical signals.It is the modulation of amplitude and phase that signal is carried out according to 64QAM signals when carrying out above-mentioned 64QAM modulation, the 64QAM signals are actually the combinations of modulation that each constellation point in the 64QAM planispheres shown in Fig. 2, the planisphere illustrates a kind of amplitude and phase.The embodiment of the present invention is illustrated to the generation method of the 64QAM signals, and how description generates the 64QAM planispheres shown in Fig. 2.
Embodiment one
The 64QAM signal creating methods of the present embodiment, it is to be performed by the system including double drive I/Q modulators, double structures for driving I/Q modulator therein may refer to Fig. 3, and Fig. 3 is the double drive I/Q modulator structures and schematic diagram in the embodiment of 64QAM signal creating methods one of the present invention.
Wherein, this pair, which drives I/Q modulator, to be included being respectively arranged with sub- modulator on I arms and Q arms, the I arms and Q arms, specifically, the sub- modulator that the sub- modulator set on I arms is properly termed as setting on the first sub- modulator, Q arms is properly termed as the second sub- modulator；For example, above-mentioned each sub- modulator is Mach-Zehnder modulator（Mach-zahnderModulator, referred to as： MZM ) .
The first sub- modulator and the second sub- modulator also include two arms respectively, and each arm is provided with a driving electrical interface, so every sub- modulator includes two driving electrical interfaces；Specifically, the first sub- modulator sets first to drive electrical interface and the second driving electrical interface；For example, with reference to Fig. 3, the first sub- modulator on I arms drives electrical interface 1 provided with first+(positive pole electrical interface）With the second driving electrical interface Γ (negative pole electrical interfaces）；The second sub- modulator on Q arms sets the 3rd to drive electrical interface and the 4th driving electrical interface, and for example, with reference to Fig. 3, the second sub- modulator on Q arms drives electrical interface Q+ (positive pole electrical interfaces provided with the 3rd）With the 4th driving electrical interface Q- (negative pole electrical interfaces）.Each above-mentioned driving electrical interface is to drive electric signal for receiving, and the modulation of line amplitude and phase can be entered to light by loading the driving electric signal, Signal of the generation with different amplitudes and phase.
The 64QAM signal creating methods of the present embodiment are referring to Fig. 4, Fig. 4 is the schematic flow sheet of the embodiment of 64QAM signal creating methods one of the present invention, it should be noted that, following 401,402 etc. are only intended to distinguish each process part in flow, but are not intended to limit the execution sequence of each step：
401st, each sub- modulator being arranged on double I arms and Q arms driven in I/Q modulator receives two level drive signals and four level drive signals respectively；
Two driving electrical interfaces that this pair drives each sub- modulator of I/Q modulator receive two level drive signals respectively（Binary Signal in Fig. 3) and four level drive signals（4ASK Signal in Fig. 3).
Specifically, the first sub- modulator on the I arms, can receive first liang of level drive signal by the described first driving electrical interface, the one or four level drive signal is received by the described second driving electrical interface；For example, first liang of level drive signal can be received by the first driving electrical interface Γ, the one or four level drive signal is received by the second driving electrical interface Γ；Or, by the second driving electrical interface 1+The one or four level drive signal is received, the first driving electrical interface Γ receives first liang of level drive signal.
Specifically, the second sub- modulator on the Q arms, second liang of level drive signal is received by the described 3rd driving electrical interface, the two or four level drive signal is received by the described 4th driving electrical interface；For example, can be by the 3rd driving electrical interface Q+Second liang of level drive signal is received, the two or four level drive signal is received by the 4th driving electrical interface Q-；Or, by the 4th driving electrical interface Q+The two or four level drive signal is received, the 3rd driving electrical interface Q- receives second liang of level drive signal.
In addition, the multilevel type that the electrical interface of the identical polar of I arms and Q arms is received can be different, for example, the first driving electrical interface 1+First liang of level drive signal is received, the second driving electrical interface Γ receives the one or four level drive signal；And the 3rd driving electrical interface Q+The two or four level drive signal is received, the 4th driving electrical interface receives second liang of level drive signal.Two described level drive signals are the electric signals with two kinds of level magnitudes, and four described level drive signals are the electric signals with four kinds of level magnitudes, are more conventional electric signal.
402nd, it is double to drive the optical signal that I/Q modulator receives input, and the optical signal is divided into the first input optical signal and the second input optical signal, the second sub- modulator on the first sub- modulator on the first input optical signal input I arms, the second input optical signal input Q arms；
Double drive I/Q modulators of the present embodiment are to be modulated generation 64QAM signals for the optical signal to input, referring to Fig. 3, the optical signal of the input is, for example, the continuous light produced by laser, the double input ports for driving I/Q modulator of optical signal input that the laser is produced, into double drive I/Q modulators. There is I arms and Q arms because this pair drives I/Q modulator, so after double drive I/Q modulators are entered, optical signal will be divided into two-way（Referring to shown in Fig. 3 arrow）, the first sub- modulator on input I arms, the second sub- modulator that another road is inputted on Q arms, can be referred to as the first input optical signal by the optical signal that input I arms, the optical signal for inputting Q arms is referred to as into the second input optical signal all the way.And, before point modulator of second input optical signal on Q arms are entered, Phase Processing can also be carried out, so that the phase difference between the second input optical signal and the first input optical signal is 90 degree, referring to the phase-modulator in Fig. 3, the phase-modulator is mainly used to allow I arms and the optical signal phase of Q arms is orthogonal, to cause the I axis components and Q axis components that can subsequently be formed in final 64QAM planispheres.
403rd, each sub- modulator on I arms and Q arms is modulated to the optical signal of input according to two level drive signals and four level drive signals and converts thereof into 8 rank amplitude phase modulation signal outputs；
Each sub- modulator on I arms and Q arms, is mainly used in the modulation entered to optical signal in line amplitude, is to carry out amplitude modulation(PAM) and phase-modulation according to two above-mentioned level drive signals and four level drive signals.
Specifically, in the present embodiment, electrical interface is driven by two of the sub- modulator on I arms or Q arms, two level drive signals and four level drive signals are received respectively, and control the amplitude of two level drive signal and four level drive signals, it is possible to so that can export 8 rank amplitude phase modulation signals on I arms or Q arms；For example, the first sub- modulator on I arms, first input optical signal can be modulated into by the one 8 rank amplitude phase modulation signal output based on the first liang of level drive signal received and the two or four level drive signal；The second sub- modulator on Q arms, can be modulated into the 2nd 8 rank amplitude phase modulation signal output based on second liang of level drive signal and the two or four level drive signal by second input optical signal.
The one 8 rank amplitude phase modulation signal of I arms output may refer to Fig. 5, schematic diagrames of the Fig. 5 for the I arms output signal in the embodiment of 64QAM signal creating methods one of the present invention on a complex plane.First input optical signal can export the one 8 rank amplitude phase modulation signal after first liang of level drive signal and the amplitude modulation(PAM) of the one or four level drive signal that the first sub- modulator on I arms is received；One 8 rank amplitude phase modulation signal is the component for the I direction of principal axis being located on 64QAM planispheres, the component includes 8 constellation points of I direction of principal axis, 8 constellation points are in existing arrangement, orientation is parallel with I direction of principal axis, it is overall to there is certain offset relative to I axles, referring to " I-Offset " in Fig. 5.
The 2nd 8 rank amplitude phase modulation signal of Q arms output may refer to Fig. 6, schematic diagrames of the Fig. 6 for the Q arms output signal in the embodiment of 64QAM signal creating methods one of the present invention on a complex plane.Second input optical signal in the second liang of level drive signal received by the second sub- modulator on Q arms and After the amplitude modulation(PAM) of two or four level drive signal, the 2nd 8 rank amplitude phase modulation signal can be exported；2nd 8 rank amplitude phase modulation signal is the component for the Q direction of principal axis being located on 64QAM planispheres, the component includes 8 constellation points of Q direction of principal axis, row arrangement is presented in 8 constellation points, orientation is parallel with Q axles, it is overall to there is certain offset relative to Q axles, referring to " Q-Offset " in Fig. 6.
404th, double drive I/Q modulators merge by the one 8 rank amplitude phase modulation signal, with the 2nd 8 rank amplitude phase modulation signal, generate 64QAM signals.
Wherein, referring to Fig. 3, the signal of I arms and Q the arms output of double drive I/Q modulators is coherent signal, and i.e. synthesis 64QAM signals are interfered after merging；I.e. this pair drive I/Q modulator I arms are exported the one 8 rank amplitude phase modulation signal, with Q arms output the 2nd 8 rank amplitude phase modulation signal merge and interfere, by the way of relevant merging, ultimately form 64QAM signals, 64QAM planispheres i.e. shown in Fig. 7, Fig. 7 is the 64QAM planispheres that export in the embodiment of 64QAM signal creating methods one of the present invention.Interventional procedures show as vector addition in complex plane, and Fig. 7 is the result after Fig. 5 and Fig. 6 vector additions.
64QAM signal creating methods in the present embodiment, used double drive I/Q modulators are the devices of commercialization, and used two level and four level drive signals are also the relatively simple drive signal easily produced, therefore, the cost using this method generation 64QAM signals is relatively low；Also, the program only needs to two level of control input and the amplitude of four level drive signals, it becomes possible to generate 64QAM signals；Because the system in the program simplifies, the producing method of drive signal is also simplified so that the generation scheme of 64QAM signals is simple, and the stability of the system is high.
Embodiment two
The present embodiment mainly illustrates some optional schemes of 64QAM signal creating methods, such as, four level drive signal, is to be obtained by the different two level drive signals synthesis of two amplitudes, two different level drive signals of described two amplitudes include：Low amplitude signal and high amplitude signals；Between two level drive signal, the low amplitude signal and the high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4.Wherein, four level signals of synthesis are common technologies, are no longer described in detail；For example, low level signal and high level signal are passed through into an electro synthesis device（Combiner four level signals can) be synthesized.Two different level drive signals of described two amplitudes include：Low amplitude signal and high amplitude signals, described " low " and " height " is the relative concept of the two two level drive signals, for example, differ smaller between two kinds of level magnitudes in one of them two level drive signal, then it is referred to as low amplitude signal, differ larger between two kinds of level magnitudes in another two level drive signal, be then referred to as height Range signal.
Specifically, the four level drivers range signal can be superimposed to be formed using two two level signals.It is assumed that signal is undamped during two two level signals synthesize four level signals, the amplitude proportional of two two level signals is designed as： A:B( A<), B another two level drive signals amplitude is C.In 64QAM signals are produced, the amplitude relation requirement of three signals is：Tri- signals of A, B, C are arranged with random order, and ratio meets 1:2:4. tri- signal amplitude relations of such as A, B, C can be： 1:2:4 or 1:4:2 or 2:4:1.
It is three kinds of optional amplitude proportionals referring to table 1 below：
The amplitude proportional of each drive signal
For example, the amplitude proportional between the first low amplitude signal, first high amplitude signals and first liang of level drive signal is： 1:2:4;Amplitude proportional between the second low amplitude signal, second high amplitude signals and second liang of level drive signal is： 1:2:4;
Or, the amplitude proportional between the first low amplitude signal, first liang of level drive signal and first high amplitude signals is： 1:2:4;Amplitude proportional between the second low amplitude signal, second liang of level drive signal and second high amplitude signals is： 1:2:4;
Or, the amplitude proportional between first liang of level drive signal, the first low amplitude signal and first high amplitude signals is 1:2:4;Amplitude proportional between second liang of level drive signal, the second low amplitude signal and second high amplitude signals is 1:2:4.
Using three kinds of amplitude proportional schemes in above-mentioned table 1, the generation of 64QAM signals can be realized, and is able to ensure that double I/Q modulators of driving work in linear zone.Wherein, scheme number is 1 amplitude proportional relation, i.e., the amplitude proportional between described two level drive signal, the low amplitude signal and the high amplitude signals is： 4: 1:2, it is assumed that two minimum level signal amplitudes are Vd, then two two level signal amplitude respectively V of four level are synthesizeddAnd 2Vd, it is 4V as the amplitude of two level signals of drivingd.In these three schemes, input is each on point modulator on the double I arms or Q arms for driving I/Q modulator of the first scheme Drive signal amplitude it is closest, therefore modulation causes signal chirp minimum, the 64QAM signal constellation points of generation are also minimum with respect to the offset of complex plane origin, therefore this amplitude proportional relation enables to the 64QAM signals produced to have preferable performance.
Embodiment three
Fig. 8 is the structural representation of the embodiment of 64QAM signal generating systems one of the present invention, and the system includes：First drive signal generating means 81, the second drive signal generating means 82, the 3rd drive signal generating means 83, fourth drive signal generating means 84 and double drive I/Q modulators 85;Wherein, double structures for driving I/Q modulator 85 may refer to described in any embodiment above, repeat no more.
The first drive signal generating means 81, for generating first liang of level drive signal；The second drive signal generating means 82, for generating the one or four level drive signal；The 3rd drive signal generating means 83, for generating second liang of level drive signal；The fourth drive signal generating means 84, for generating the two or four level drive signal；Double drive I/Q modulators 85, are used for：The optical signal of input is received, and the optical signal is divided into the second sub- modulator on the first sub- modulator on the first input optical signal and the second input optical signal, the first input optical signal input I arms, the second input optical signal input Q arms；The first sub- modulator on the I arms, first liang of level drive signal is received by the described first driving electrical interface, one or four level drive signal is received by the described second driving electrical interface, and first input optical signal is modulated into by the one 8 rank amplitude phase modulation signal output based on first liang of level drive signal and the two or four level drive signal；The second sub- modulator on the Q arms, it receives second liang of level drive signal by the described 3rd driving electrical interface, two or four level drive signal is received by the described 4th driving electrical interface, and second input optical signal is modulated into by the 2nd 8 rank amplitude phase modulation signal output based on second liang of level drive signal and the two or four level drive signal；
Double I/Q modulators of driving are additionally operable to merge by the one 8 rank amplitude phase modulation signal of the described first sub- modulator output, with the 2nd 8 rank amplitude phase modulation signal of the described second sub- modulator output, generate 64QAM signals.
Optionally, the phase difference between the second input optical signal that the described second sub- modulator on the first input optical signal and the Q arms that the described first sub- modulator on the I arms is received is received is 90 degree.For example, described point of modulator, is MZM modulator.
Fig. 9 is the structural representation of another embodiment of 64QAM signal generating systems of the present invention, as shown in Fig. 9, on the basis of structure shown in Fig. 8； Optionally, the second drive signal generating means 82 can include：First signal generation sub-device 821, secondary signal generation sub-device 822 and signal synthesis sub-device 823;Wherein,
First signal generation sub-device 821, for generating the first low amplitude signal；
Secondary signal generates sub-device 822, and for generating the first high amplitude signals, the first low amplitude signal and the first high amplitude signals are two different level drive signals of two amplitudes；
Signal synthesizes sub-device 823, for being synthesized by two different level drive signals of described two amplitudes, obtains the one or four level drive signal.
Between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4.
The fourth drive signal generating means 84, including：
3rd signal generation sub-device 841, for generating the second low amplitude signal；
4th signal generation sub-device 842, for generating the second high amplitude signals, the second low amplitude signal and the second high amplitude signals are two different level drive signals of two amplitudes；
Signal synthesizes sub-device 843, for being synthesized by two different level drive signals of described two amplitudes, obtains the two or four level drive signal；
Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4.
Optionally, between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between the first low amplitude signal, first high amplitude signals and first liang of level drive signal is： 1 :2:4;
Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
Amplitude proportional between the second low amplitude signal, second high amplitude signals and second liang of level drive signal is： 1 :2:4.
Optionally, between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between the first low amplitude signal, first liang of level drive signal and first high amplitude signals is： 1 :2:4;
Second liang of level drive signal, the second low amplitude signal and second high amplitude signals Between, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between the second low amplitude signal, second liang of level drive signal and second high amplitude signals is： 1 :2:4.
Optionally, between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：Amplitude proportional between first liang of level drive signal, the first low amplitude signal and first high amplitude signals is 1:2:4;Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including；Amplitude proportional between second liang of level drive signal, the second low amplitude signal and second high amplitude signals is 1:2:4.
Optionally, the first driving electrical interface and the 3rd drives electrical interface to be positive pole electrical interface, and the second driving electrical interface and the 4th driving electrical interface are negative pole electrical interfaces.
One of ordinary skill in the art will appreciate that：Realizing all or part of step of above method embodiment can be completed by the related hardware of programmed instruction, foregoing program can be stored in a computer read/write memory medium, the program upon execution, performs the step of including above method embodiment；And foregoing storage medium includes：ROM, RAM, magnetic disc or CD etc. are various can be with the medium of store program codes.
Finally it should be noted that：Various embodiments above is merely illustrative of the technical solution of the present invention, rather than its limitations；Although the present invention is described in detail with reference to foregoing embodiments, it will be understood by those within the art that：It can still modify to the technical scheme described in foregoing embodiments, or carry out equivalent substitution to which part or all technical characteristic；And these modifications or replacement, the essence of appropriate technical solution is departed from the scope of various embodiments of the present invention technical scheme.

Claims (8)

  1. Claims
    1st, a kind of 64QAM signal creating methods, it is characterised in that methods described is performed by the system including double drive IQ modulators, double I/Q modulators of driving are used for the optical signal modulation of the input into the 64QAM signals；Double I/Q modulators of driving include setting the first sub- modulator on I arms and Q arms, the I arms, and the first sub- modulator includes the first driving electrical interface and the second driving electrical interface；Second sub- modulator is set on the Q arms, and the second sub- modulator includes the 3rd driving electrical interface and the 4th driving electrical interface；The 64QAM signal creating methods include：
    Double I/Q modulators of driving receive the optical signal inputted, and the optical signal is divided into the first input optical signal and the second input optical signal, the described second sub- modulator on the described first sub- modulator on the first input optical signal input I arms, the second input optical signal input Q arms；
    The first sub- modulator on the I arms, first liang of level drive signal is received by the described first driving electrical interface, one or four level drive signal is received by the described second driving electrical interface, and first input optical signal is modulated into by the one 8 rank amplitude phase modulation signal output based on first liang of level drive signal and the two or four level drive signal；
    The second sub- modulator on the Q arms, second liang of level drive signal is received by the described 3rd driving electrical interface, two or four level drive signal is received by the described 4th driving electrical interface, and second input optical signal is modulated into by the 2nd 8 rank amplitude phase modulation signal output based on second liang of level drive signal and the two or four level drive signal；
    Double I/Q modulators of driving merge by the one 8 rank amplitude phase modulation signal, with the rank amplitude phase modulation signal of the 2nd Q arms 8, generate 64QAM signals.
    2nd, according to the method described in claim 1, characterized in that, the phase difference between the second input optical signal that the described second sub- modulator on the first input optical signal and the Q arms that the described first sub- modulator on the I arms is received is received is 90 degree.
    3rd, method according to claim 1 or 2, it is characterised in that
    One or four level drive signal is obtained by the different two level drive signals synthesis of two amplitudes, and two different level drive signals of described two amplitudes include：First low amplitude signal and the first high amplitude signals；
    Between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1:2:4;
    Two or four level drive signal is synthesized by two different level drive signals of two amplitudes Arrive, two different level drive signals of described two amplitudes include：Second low amplitude signal and the second high amplitude signals；
    Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4.
    4th, method according to claim 3, it is characterised in that between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Amplitude proportional between the first low amplitude signal, first high amplitude signals and first liang of level drive signal is： 1 :2:4;
    Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Amplitude proportional between the second low amplitude signal, second high amplitude signals and second liang of level drive signal is： 1 :2:4.
    5th, method according to claim 3, it is characterised in that between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Amplitude proportional between the first low amplitude signal, first liang of level drive signal and first high amplitude signals is： 1 :2:4;
    Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Amplitude proportional between the second low amplitude signal, second liang of level drive signal and second high amplitude signals is： 1 :2:4.
    6th, method according to claim 3, it is characterised in that between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Amplitude proportional between first liang of level drive signal, the first low amplitude signal and first high amplitude signals is 1:2:4;
    Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Second liang of level drive signal, the second low amplitude signal and second high amplitude signals Between amplitude proportional be 1:2:4.
    7th, according to any described methods of claim 1-6, it is characterised in that the first driving electrical interface and the 3rd drives electrical interface to be positive pole electrical interface, the second driving electrical interface and the 4th driving electrical interface are negative pole electrical interfaces.
    8th, a kind of 64QAM signal generating systems, it is characterised in that including：First drive signal generating means, the second drive signal generating means, the 3rd drive signal generating means, fourth drive signal generating means and double drive I/Q modulators；Double I/Q modulator of driving is used for the optical signal modulation of the input into the 64QAM signals；Double I/Q modulators of driving include setting the first sub- modulator on I arms and Q arms, the I arms, and the first sub- modulator includes the first driving electrical interface and the second driving electrical interface；Second sub- modulator is set on the Q arms, and the second sub- modulator includes the 3rd driving electrical interface and the 4th driving electrical interface；Wherein,
    The first drive signal generating means, for generating first liang of level drive signal；
    The second drive signal generating means, for generating the one or four level drive signal；
    The 3rd drive signal generating means, for generating second liang of level drive signal；
    The fourth drive signal generating means, for generating the two or four level drive signal；
    Double drive I/Q modulators, are used for：The optical signal of input is received, and the optical signal is divided into the second sub- modulator on the first sub- modulator on the first input optical signal and the second input optical signal, the first input optical signal input I arms, the second input optical signal input Q arms；The first sub- modulator on the I arms, first liang of level drive signal is received by the described first driving electrical interface, one or four level drive signal is received by the described second driving electrical interface, and first input optical signal is modulated into by the one 8 rank amplitude phase modulation signal output based on first liang of level drive signal and the two or four level drive signal；The second sub- modulator on the Q arms, it receives second liang of level drive signal by the described 3rd driving electrical interface, two or four level drive signal is received by the described 4th driving electrical interface, and second input optical signal is modulated into by the 2nd 8 rank amplitude phase modulation signal output based on second liang of level drive signal and the two or four level drive signal；
    Double I/Q modulators of driving are additionally operable to merge by the one 8 rank amplitude phase modulation signal of the described first sub- modulator output, with the 2nd 8 rank amplitude phase modulation signal of the described second sub- modulator output, generate 64QAM signals.
    9th, system according to claim 8, it is characterised in that the first input optical signal that the described first sub- modulator on the I arms is received is received with the described second sub- modulator on the Q arms Phase difference between second input optical signal is 90 degree.
    10th, system according to claim 8 or claim 9, it is characterised in that
    The second drive signal generating means, including：
    First signal generation sub-device, for generating the first low amplitude signal；
    Secondary signal generates sub-device, and for generating the first high amplitude signals, the first low amplitude signal and the first high amplitude signals are two different level drive signals of two amplitudes；
    Signal synthesizes sub-device, for being synthesized by two different level drive signals of described two amplitudes, obtains the one or four level drive signal；
    Between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4;
    The fourth drive signal generating means, including：
    3rd signal generation sub-device, for generating the second low amplitude signal；
    4th signal generation sub-device, for generating the second high amplitude signals, the second low amplitude signal and the second high amplitude signals are two different level drive signals of two amplitudes；
    Signal synthesizes sub-device, for being synthesized by two different level drive signals of described two amplitudes, obtains the two or four level drive signal；
    Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4.
    11st, system according to claim 10, it is characterised in that between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Amplitude proportional between the first low amplitude signal, first high amplitude signals and first liang of level drive signal is： 1 :2:4;
    Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Amplitude proportional between the second low amplitude signal, second high amplitude signals and second liang of level drive signal is： 1 :2:4.
    12nd, system according to claim 10, it is characterised in that between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including： Amplitude proportional between the first low amplitude signal, first liang of level drive signal and first high amplitude signals is： 1 :2:4;
    Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Amplitude proportional between the second low amplitude signal, second liang of level drive signal and second high amplitude signals is： 1 :2:4.
    13rd, system according to claim 10, it is characterised in that between first liang of level drive signal, the first low amplitude signal and first high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Amplitude proportional between first liang of level drive signal, the first low amplitude signal and first high amplitude signals is 1:2:4;
    Between second liang of level drive signal, the second low amplitude signal and second high amplitude signals, after arranging in any order, the amplitude proportional of three is met： 1 :2:4, including：
    Amplitude proportional between second liang of level drive signal, the second low amplitude signal and second high amplitude signals is 1:2:4.
    14th, according to any described system of claim 8 13, it is characterised in that the first driving electrical interface and the 3rd drives electrical interface to be positive pole electrical interface, the second driving electrical interface and the 4th driving electrical interface are negative pole electrical interfaces.
CN201380000294.1A 2013-02-27 2013-02-27 64qam signal generation method and system Pending CN104185975A (en)

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CN101964683A (en) * 2010-09-21 2011-02-02 上海大学 Serial-parallel connection modulation optical frequency multiplication millimeter-wave RoF (Radio Over Fiber) system and QPSK (Quadrature Phase Shift Keying) /16QAM (Quadrature Amplitude Modulation) modulation method thereof
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