CN105264851A

CN105264851A - Method, apparatus and system for transmitting signal

Info

Publication number: CN105264851A
Application number: CN201380002805.3A
Authority: CN
Inventors: 彭桂开; 周雷; 湛永坚; 王振平
Original assignee: Huawei Technologies Co Ltd
Current assignee: Pinghu Xinna Communication Technology Co ltd
Priority date: 2013-11-13
Filing date: 2013-11-13
Publication date: 2016-01-20
Anticipated expiration: 2033-11-13
Also published as: WO2015070395A1; CN105264851B

Abstract

Provided is a method for transmitting a signal, which can lower the sampling rate requirements of a digital-to-analogue converter at low costs so as to reduce the costs of communication devices and network construction. The method comprises: acquiring, by a sending end, a target digital signal required to be sent to a receiving end; determining, by the sending end, a target DAC corresponding to a target frequency band from the at least two DACs, wherein the target frequency band is a frequency band used by the sending end and the receiving end to communicate, and the target frequency band belongs to a characteristic Nyquist domain corresponding to the target DAC; processing, by the sending end, the target digital signal via the target DAC so as to generate a target analogue signal; and sending, by the sending end, the target analogue signal to the receiving end through the target frequency band.

Description

Method, apparatus and system for transmitting signal

Transmit the methods, devices and systems technical field of signal

The present invention relates to the communications field, and more particularly, to the methods, devices and systems of transmission signal.Background technology

A kind of known multi-carrier modulation technology, the channel given is divided into many orthogonal subchannels in frequency domain, it is modulated on each of the sub-channels using a subcarrier, subcarrier can improve power system capacity using high order modulation, and the data flow of high speed can be assigned to several subcarrier low speed transmissions by each subcarrier parallel transmission, this parallel transmission technology.

For example, in a kind of point-to-multipoint Transmission system, transmitting terminal is by the data of whole system（Need to be sent to multiple receiving terminals) it is carried on a single band progress multi-carrier modulation, data after modulation are broadcast to all receiving terminals, each receiving terminal must receive the data in whole frequency band, then be demodulated reception to one's name subcarrier.This transmission means, require very high for the digital analog converter of transmitting terminal, it is assumed that transmission band is 10GHz, then at least needs the digital analog converter that sample rate is 20GSps, current device cost is high, unacceptable for the strict access network of cost requirement.

A kind of possible mode is, transmitting terminal utilizes the different orthogonal (I/Q in the same direction of centre frequency in analog domain, In-phase/Quadrature) modulator upconverts to multiple baseband signals on different frequency bands, forms multi-band signal and is sent to receiving terminal.

But, the I/Q modulators of high speed are difficult to obtain, and cost is still difficult to decline.In addition, because the same phase and orthogonal two branch road of I/Q modems are inconsistent, for example, there may be the gain difference of frequency mixer causes amplitude imbalance, and the phase difference of two local oscillation signals is not that strict 90 ° cause unbalance in phase, and, there is the unbalanced problem of I/Q two-way, the change of baseband I/Q signal can be caused, that is, produce I/Q imbalance problems, ultimately result in performance degradation.

Accordingly, it is desirable to provide a kind of method for transmitting signal, the sample rate requirement of digital analog converter can be reduced at low cost.The content of the invention

The embodiment of the present invention provides a kind of methods, devices and systems for transmitting signal, and the sample rate requirement of digital analog converter can be reduced at low cost, and then reduces the cost of communication equipment and networking. First aspect, there is provided a kind of method for transmitting signal, performed by the transmitting terminal in communication system, the transmitting terminal has at least two digital analog converter DAC, feature Nyquist domain respectively corresponding to the DAC is different, wherein, this feature Nyquist domain is the processing through corresponding DAC and the Nyquist domain at the maximum output intensity of analog signal that generates, the sample rate that at least two DAC is used is identical, the system bandwidth that the communication system is used is divided at least two frequency ranges, one frequency range belongs to the feature Nyquist domain corresponding to a DAC, this method includes：The transmitting terminal, which is obtained, to be needed to be sent to the target number signal of receiving terminal；The transmitting terminal determines the target DAC corresponding with target frequency bands from least two DAC, wherein, the target frequency bands, which are the transmitting terminals, with the receiving terminal communicate the frequency range used, and the target frequency bands belong to the feature Nyquist domain corresponding to target DAC；The transmitting terminal is handled the target number signal by target DAC, to generate target simulation signal；The transmitting terminal sends the target simulation signal by the target frequency bands to the receiving terminal.

With reference in a first aspect, in the first implementation of first aspect, when the feature Nyquist domain corresponding to target DAC is not the first Nyquist domain, this method also includes：The transmitting terminal sends Nyquist domain configured information to the receiving terminal, and the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands.

With reference to first aspect and its above-mentioned implementation, in second of implementation of first aspect, the transmitting terminal determines the target DAC corresponding with target frequency bands from least two DAC, including：The transmitting terminal receives the registration request of receiving terminal transmission；From at least two frequency range, the target frequency bands are distributed for the receiving terminal according to the registration request for the transmitting terminal；The transmitting terminal determines target DAC according to the target frequency bands from least two DAC;And this method also includes：The transmitting terminal sends the frequency range configured information for indicating the target frequency bands to the receiving terminal.

With reference to first aspect and its above-mentioned implementation, in the third implementation of first aspect, the transmitting terminal determines the target DAC corresponding with target frequency bands from least two DAC, including：The transmitting terminal obtains mapping item, and the mapping item records the mapping relations between the receiving terminal and the target frequency bands；The transmitting terminal searches the mapping item according to the receiving terminal, to determine the target frequency bands；The transmitting terminal determines target DAC according to the target frequency bands.

With reference to first aspect and its above-mentioned implementation, in the 4th kind of implementation of first aspect, the receiving terminal can be at least two frequency range any frequency range communicated, and the transmitting terminal determines the target DAC corresponding with target frequency bands from least two DAC, including：The transmitting terminal regard any DAC at least two DAC as target DAC;The transmitting terminal determines the target frequency bands from the feature Nyquist domain corresponding to target DAC；And this method also includes：The transmitting terminal to this Receiving terminal sends the frequency range configured information for indicating the target frequency bands.

With reference to first aspect and its above-mentioned implementation, in the 5th kind of implementation of first aspect, in the transmitting terminal by the target frequency bands, before sending the target simulation signal to the receiving terminal, this method also includes：The transmitting terminal carries out the first filtering process, to retain the feature Nyquist domain being in corresponding to target DAC or the part of the target frequency bands of the target simulation signal.

With reference to first aspect and its above-mentioned implementation, in the 6th kind of implementation of first aspect, in the transmitting terminal by the target frequency bands, before sending the target simulation signal to the receiving terminal, this method also includes：The transmitting terminal carries out the second filtering process, to retain the target simulation signal in the feature Nyquist domain corresponding to target DAC or the target frequency bands.

Second aspect includes there is provided a kind of method for transmitting signal, this method：The receiving terminal determines target frequency bands, and the target frequency bands, which are the transmitting terminals, with the receiving terminal communicate the frequency range used；The receiving terminal obtains the target simulation signal of transmitting terminal transmission according to the target frequency bands；The receiving terminal receives the Nyquist domain configured information of transmitting terminal transmission, and the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands；The receiving terminal determines respective components of the target simulation signal in the first Nyquist domain according to the Nyquist domain configured information；Respective components of the receiving terminal according to the target simulation signal in the first Nyquist domain, analog-to-digital conversion process is carried out to the target simulation signal.

With reference to second aspect, in the first implementation of second aspect, the receiving terminal determines target frequency bands, including：The receiving terminal receives the frequency range configured information for being used to indicate the target frequency bands of transmitting terminal transmission, and the target frequency bands are that the transmitting terminal is distributed from least two frequency range for the receiving terminal；The receiving terminal determines the target frequency bands according to the frequency range configured information.

With reference to second aspect and its above-mentioned implementation, in second of implementation of second aspect, the receiving terminal receive the transmitting terminal transmission be used for indicate the frequency range configured information of the target frequency bands before, this method also includes：The receiving terminal sends registration request to the transmitting terminal, in order to which the transmitting terminal distributes the target frequency bands from least two frequency range according to the registration request for the receiving terminal, and sends the frequency range configured information.

With reference to second aspect and its above-mentioned implementation, in the third implementation of second aspect, the receiving terminal determines target frequency bands, including：The receiving terminal obtains mapping item, and mapping item record has the mapping relations between the receiving terminal and the target frequency bands；The receiving terminal searches the mapping item, to determine the target frequency bands.

The third aspect includes there is provided a kind of device for transmitting signal, the device：At least two digital analog converter DAC, respectively the feature Nyquist domain corresponding to the DAC is different, wherein, this feature Nai Kuisi Special domain is the processing through corresponding DAC and the Nyquist domain at the maximum output intensity of analog signal that generates, the sample rate that at least two DAC is used is identical, the system bandwidth that the communication system is used is divided at least two frequency ranges, and the frequency range belongs to the feature Nyquist domain corresponding to a DAC；Acquiring unit, needs to be sent to the target number signal of receiving terminal for obtaining；Determining unit, for determining the target DAC corresponding with target frequency bands from least two DAC, wherein, the target frequency bands to be the device with the receiving terminal the communicate frequency range used, the target frequency bands belong to the feature Nyquist domain corresponding to target DAC；Generation unit, for being handled by target DAC the target number signal, to generate target simulation signal；Transmit-Receive Unit, for by the target frequency bands, the target simulation signal to be sent to the receiving terminal.

With reference to the third aspect, in the first implementation of the third aspect, when the feature Nyquist domain corresponding to target DAC is not the first Nyquist domain, the Transmit-Receive Unit is additionally operable to send Nyquist domain configured information to the receiving terminal, and the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands.

With reference to the third aspect and its above-mentioned implementation, in second of implementation of the third aspect, the Transmit-Receive Unit is additionally operable to receive the registration request that the receiving terminal is sent；The determining unit is additionally operable to according to the registration request, from least two frequency range, and the target frequency bands are distributed for the receiving terminal, and according to the target frequency bands, target DAC is determined from least two DAC;The Transmit-Receive Unit is additionally operable to send the frequency range configured information for indicating the target frequency bands to the receiving terminal.

With reference to the third aspect and its above-mentioned implementation, in the third implementation of the third aspect, the acquiring unit is additionally operable to obtain mapping item, and mapping item record has the mapping relations between each receiving terminal and each frequency range；The determining unit is specifically for according to the receiving terminal, searching the mapping item, to determine the target frequency bands, and according to the target frequency bands, determines target DAC.

With reference to the third aspect and its above-mentioned implementation, in the 4th kind of implementation of the third aspect, the receiving terminal can be at least two frequency range any frequency range communicated, and the determining unit is specifically for regarding any DAC at least two DAC as target DAC, and from the feature Nyquist domain corresponding to target DAC, determine the target frequency bands；The Transmit-Receive Unit is additionally operable to send the frequency range configured information for indicating the target frequency bands to the receiving terminal.

With reference to the third aspect and its above-mentioned implementation, in the 5th kind of implementation of the third aspect, the generation unit is additionally operable to carry out the first filtering process, only to retain the part in the feature Nyquist domain corresponding to the target frequency bands or target DAC of the target simulation signal.

, should in the 6th kind of implementation of the third aspect with reference to the third aspect and its above-mentioned implementation Generation unit is additionally operable to carry out the second filtering process, only to retain the target simulation signal in the feature Nyquist domain corresponding to the target frequency bands or target DAC.

Fourth aspect includes there is provided a kind of device for transmitting signal, the device：Determining unit, for determining target frequency bands, the target frequency bands, which are transmitting terminals, with the device communicate the frequency range used；Transmit-Receive Unit, for according to the target frequency bands, the target simulation signal of transmitting terminal transmission is obtained, and receives the Nyquist domain configured information of transmitting terminal transmission, the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands；Processing unit, for according to the Nyquist domain configured information, determine respective components of the target simulation signal in the first Nyquist domain, and the respective components according to the target simulation signal in the first Nyquist domain, analog-to-digital conversion process is carried out to the target simulation signal, to obtain the target number signal.

With reference to fourth aspect, in the first implementation of fourth aspect, the Transmit-Receive Unit is additionally operable to receive the frequency range configured information for being used to indicate the target frequency bands that the transmitting terminal is sent, and the target frequency bands are that the transmitting terminal is distributed from least two frequency range for the receiving terminal；The determining unit is specifically for according to the frequency range configured information, determining the target frequency bands.

With reference to fourth aspect and its above-mentioned implementation, in second of implementation of fourth aspect, the Transmit-Receive Unit is additionally operable to send registration request to the transmitting terminal, in order to which the transmitting terminal distributes the target frequency bands from least two frequency range according to the registration request for the receiving terminal, and send the frequency range configured information.

With reference to fourth aspect and its above-mentioned implementation, in the third implementation of fourth aspect, the determining unit is additionally operable to obtain mapping item, and mapping item record has the mapping relations between the receiving terminal and the target frequency bands；For searching the mapping item, to determine the target frequency bands.

5th aspect, there is provided a kind of system for transmitting signal, the system includes transmitting terminal and at least one receiving terminal, the transmitting terminal at least two digital analog converter DAC, feature Nyquist domain respectively corresponding to the DAC is different, wherein, this feature Nyquist domain is the processing through corresponding DAC and the Nyquist domain at the maximum output intensity of analog signal that generates, the sample rate that at least two DAC is used is identical, the system bandwidth that the communication system is used is divided at least two frequency ranges, one frequency range belongs to the feature Nyquist domain corresponding to a DAC, and the transmitting terminal is used for acquisition and needs to be sent to the target number signal of receiving terminal, the target DAC corresponding with target frequency bands is determined from least two DAC, wherein, the target frequency bands, which are the transmitting terminals, with the receiving terminal communicate the frequency range used, the target frequency bands belong to the feature Nyquist domain corresponding to target DAC, the target number signal is handled by target DAC, to generate target simulation signal, pass through the target frequency bands, the target simulation signal is sent to the receiving terminal；The receiving terminal is used to determine target frequency bands, according to the target frequency bands, Obtain the target simulation signal of transmitting terminal transmission, receive the Nyquist domain configured information of transmitting terminal transmission, the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands, according to the Nyquist domain configured information, determine respective components of the target simulation signal in the first Nyquist domain, according to respective components of the target simulation signal in the first Nyquist domain, analog-to-digital conversion process is carried out to the target simulation signal.

The method of transmission signal according to embodiments of the present invention, device and system, by configuring multiple DAC in transmitting terminal, the maximum output intensity of the analog signal after being handled through each DAC is set to be located at different Nyquist domains, and be that each receiving terminal distributes different frequency ranges in system bandwidth, transmitting terminal to receiving terminal when sending data, according to the Frequency Band Selection target DAC corresponding with the receiving terminal, so that target frequency bands belong to the Qwest domain at target DAC maximum output intensity, and to target DAC to needing the data for being sent to the receiving terminal to handle, to generate target simulation signal, and then it is sent to the receiving terminal, so as to which receiving terminal can be according to its corresponding frequency range, target simulation signal is recognized from system bandwidth, therefore, each DAC sample rate is without corresponding with the highest frequency of system bandwidth, so as to reduce the requirement to DAC sample rates, and then reduce the cost of communication equipment and networking.Brief description of the drawings

Technical scheme in order to illustrate the embodiments of the present invention more clearly, cylinder will be made to the required accompanying drawing used in embodiment or description of the prior art below singly to introduce, apparently, drawings in the following description are only some embodiments of the present invention, for those of ordinary skill in the art, on the premise of not paying creative work, other accompanying drawings can also be obtained according to these accompanying drawings.

Fig. 1 is the indicative flowchart of the method for transmission data according to an embodiment of the invention.

Fig. 2 is the schematic diagram for the maximum output intensity distribution for representing DAC under using different shock response curve patterns.

Fig. 3 is the schematic diagram for the frequency spectrum shift effect for representing Undersampling technique.

Fig. 4 is the schematic interaction figure of the method for transmission data according to an embodiment of the invention.

Fig. 5 is the indicative flowchart of the method for transmission data according to another embodiment of the present invention.Fig. 6 is the schematic block diagram of the device of transmission data according to an embodiment of the invention.

Fig. 7 is the schematic block diagram of the device of transmission data according to another embodiment of the present invention.

Fig. 8 is the schematic diagram of the equipment of transmission data according to an embodiment of the invention.

Fig. 9 is the schematic diagram of the equipment of transmission data according to another embodiment of the present invention.Figure 10 is the schematic block diagram of the system of transmission data according to an embodiment of the invention. Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, it is clear that described embodiment is a part of embodiment of the invention, rather than whole embodiments.Based on the embodiment in the present invention, the every other embodiment that those of ordinary skill in the art are obtained under the premise of creative work is not made belongs to the scope of protection of the invention.

Fig. 1 is the indicative flowchart of the method 100 of transmission data according to an embodiment of the invention.This method 100 is performed by the transmitting terminal in communication system, the transmitting terminal has at least two digital analog converter DAC, feature Nyquist domain respectively corresponding to the DAC is different, wherein, this feature Nyquist domain is the processing through corresponding DAC and the Nyquist domain at the maximum output intensity of analog signal that generates, the sample rate that at least two DAC is used is identical, the system bandwidth that the communication system is used is divided at least two frequency ranges, one frequency range belongs to the feature Nyquist domain corresponding to a DAC, as shown in Figure 1, this method 100 includes：

S110, the transmitting terminal, which is obtained, to be needed to be sent to the target number signal of receiving terminal；

S120, the transmitting terminal determines the target corresponding with target frequency bands from least two DAC

DAC, wherein, the target frequency bands, which are the transmitting terminals, with the receiving terminal communicate the frequency range used, and the target frequency bands belong to the feature Nyquist domain corresponding to target DAC；

S130, the transmitting terminal is handled the target number signal by target DAC, to generate target simulation signal；

S140, the transmitting terminal sends the target simulation signal by the target frequency bands to the receiving terminal.Technical scheme, can apply to it is various need to make transmitting terminal convert digital signals into analog signal, and by the way of radio communication or optic communication, the analog signal is sent to the communication system of receiving terminal, for example：In EPON（PON, Passive Optical Network) in, PON local sides are with a trunk optical fiber, you can be divided into tens of even more multi-channel optical fibres connection users, substantially reduce networking cost.Current PON technologies mainly have ethernet passive optical network（EPON, Ethernet Passive Optical Network) and gigabit passive optical network（GPON, Gigabit- Capable Passive Optical Network) etc. it is several, its Main Differences is to employ two layers of different technologies.Existing EPON and GPON products can use OFDM-EPON（OFDM-PON, Orthogonal Frequency Division Multiplexing Passive Optical Network) etc. different technologies scheme.OFDM-PON technologies can not only introduce transmitting terminal and receiving terminal Electric signal processing to eliminate various damages, and may be incorporated into high order modulation reduces the bandwidth requirement of various photoelectric devices, in addition the skill Art also has the advantages that the multiple access access of high efficient and flexible and resource allocation methods, therefore has obtained industry and widely pay close attention to.

In pon, optical line terminal（OLT Optical Line Terminal) can be with one or more optical network units（ONU, Optical Network Unit) communication connection, also, an ONU can use P0N system bandwidth（In other words, system carrier）In a part of frequency range（In other words, subcarrier）Communicated, in P0N downlink transmission process, 0LT needs the data by each 0NU is sent to, and then multi-carrier modulation to whole system bandwidth is broadcasted to each 0NU.

Hereinafter, for the ease of understanding and illustrating, the method 100 of the transmission signal of the embodiment of the present invention is applied to process during PON（Specifically, it is downlink transmission process）Exemplified by, illustrate, in this case, OLT is equivalent to transmitting terminal, ONU is equivalent to receiving terminal.

In embodiments of the present invention, OLT can be communicated to connect with multiple ONU, also, the frequency range in system bandwidth used in communications of each ONU within the same period is different（That is, situation 1), or, OLT can be communicated to connect with ONU, also, the ONU within a period can use system bandwidth in any frequency range（The width of the frequency range is less than system bandwidth）Communicated（That is, situation 2) below, the action in the case of both the above is illustrated respectively respectively.

Situation 1

In S110,0LT (one of transmitting terminal）Can be from network to network interface（NNI, Network to Network Interface) obtain need to be sent to coupled multiple optical network units（0NU, Optical Network Unit) data flow frame, and it is possible to carry out solution frame, the framing procedure for above-mentioned data flow frame for example, by, media access control MAC (Media Access Control) module.So as to for example, can distinguish needs according to the destination address of the MAC layer of each data flow frame and be sent to for example, 0NU#1 (one of receiving terminal）Data, thereafter, can to the data carry out OFDM (OFDM, Orthogonal Frequency Division Multiplexing) modulate, so as to generate real number OFDM baseband signals（One of target number signal）.

Wherein, OFDM modulation is a kind of multi-carrier modulation technology, its basic thought be in frequency domain by channel be divided into many orthogonal subchannels, be modulated on each of the sub-channels using a subcarrier, subcarrier can use QPSK signal（QPSK, Quadrature Phase Shift Keying), quadrature amplitude modulation（QAM, Quadrature Amplitude Modulation) etc. high order modulation improve power system capacity, and each subcarrier parallel transmission, the data flow of high speed can be assigned to several subcarrier low speed transmissions by this parallel transmission technology.OFDM is that it allows subcarrier spectrum to partly overlap relative to the difference of general multi-carrier transmission, as long as mutually orthogonal between meeting subcarrier, then can be with Data-signal is separated from the subcarrier of aliasing.Because OFDM allows subcarrier spectrum aliasing, its spectrum efficiency is greatly improved, thus a kind of efficient modulation system.

The method and process for carrying out OFDM modulation to data are as follows, and first, high speed binary data stream becomes the parallel low speed binary data in M roads by serioparallel exchange These data carry out planisphere mapping by QAM mapping blocks again, and each road QAM modulation exponent number can be different, such as QPSK, QAM8, QAM16, and M roads binary data is converted into the plural X on N roads=[Xo, X_t, -, X_N- J, these plural numbers represent the qam constellation point for being used for transmission, and N is the number of OFDM system sub-carriers.N roads signal passes through inverse fast Fourier transform（IFFT, Inverse Fast Fourier Transform) realize OFDM modulate, OFDM modulation after multiple signals for χ=[χ ο,_Χι, ···, x„-J^T, in order to resist intersymbol interference (ISI, Inter-Symbol Interference) and inter-carrier interference (ICI, Inter-Carrier Interference), can before x a reinforcement mouthful cyclic prefix again（CP, Cyclic Prefix), form ^, x_CP=[x_N-_G, -, χ₀, _Xl, -, ^r, then by a parallel-serial conversion, serial data is formed, above section is completed in numeric field.

Generally, IFFT output is not a real number, but a plural number.Output to IFFT is a real number, according to the property of inversefouriertransform, it is desirable to which IFFT list entries I must is fulfilled for Hermitian conjugate symmetry（Hermitian conjugate symmetry), that is, complex conjugate symmetric is met, now IFFT output imaginary part is 0, only surplus real part.It must is fulfilled for following relation：

Work 0, work 1, * " } IN- factory Χ θ, Xlt * " } XN/2-1, XN/2 } ^ N/2-lf " ^ 1

Expression is Λ complex conjugate（I.e. real part is identical, and imaginary part is opposite）, N is IFFT points, and X0 corresponding is DC, is set to 0, corresponding is nyquist frequency, is also configured as 0 and (edge of sample rate is in, in order to prevent distortion, without it）.

In embodiments of the present invention, OLT can be configured with multiple（At least two）Digital analog converter（DAC, Digital Analog Converter), and, each DAC sample rate is identical, so that, it is identical for each DAC position and dividing mode of the Nyquist domain in system bandwidth, in other words, the quantity in each DAC Nyquist domain is identical, also, each Nyquist domain corresponding frequency range in system bandwidth is identical.If for example, as shown in Fig. 2 each DAC sample rate is 1GSPS, the width in a Nyquist domain is 0.5GHz, if in this case, system bandwidth is 3GHz, needing 6 Nyquist domains.

Also, in embodiments of the present invention, the pattern for the shock response curve that each DAC is used is different, so that, the Nyquist domain at maximum output intensity respectively through the DAC analog signals handled（That is, feature Nyquist domain）It is different each other, as shown in Fig. 2 using the first Nyquist pattern, for example, non-return-to-zero pattern（NRZ MODE, Non Return to Zero MODE) shock response curve The maximum of DAC (following, to be denoted as DAC#1) signal output intensity is in the first Nyquist domain, using the second Nyquist pattern, for example, rf-mode（RF MODE, Radio Frequency MODE) pattern shock response curve DAC (following, be denoted as DAC#2) signal output intensity maximum in the second Nyquist domain, use the 3rd Nyquist pattern, for example, zero pattern（RZ MODE, Return to Zero MODE) shock response curve DAC (following, be denoted as DAC#3) signal output intensity maximum in the 3rd Nyquist domain, use the 4th Nyquist pattern, for example, zero padding rf-mode（RFZ MODE, Zero Radio Frequency MODE) pattern shock response curve DAC (following, be denoted as DAC#4) signal output intensity maximum in the 4th Nyquist domain.I.e., in embodiments of the present invention, the analog signal generated through each DAC processing is different each other（Specifically, the Nyquist domain at maximum output intensity is different）.

It should be understood that, the pattern of each impact curve and the dividing mode in Nyquist domain shown in Fig. 2 listed above are merely illustrative, the present invention is not limited to this, the pattern of impact curve can be changed arbitrarily, also, the division in Nyquist domain can be changed with the change of sample rate and system bandwidth.

As described above, system bandwidth is divided into multiple frequency ranges, multiple ONU are communicated in a period using only a frequency range, can determine that ONU#l uses frequency range in S120, OLT.In mode A of the present invention

Alternatively, the transmitting terminal determines the target DAC corresponding with target frequency bands from least two DAC, including：

The transmitting terminal receives the registration request of receiving terminal transmission；

From at least two frequency range, the target frequency bands are distributed for the receiving terminal according to the registration request for the transmitting terminal；

The transmitting terminal determines target DAC according to the target frequency bands from least two DAC;And this method also includes：

The transmitting terminal sends the frequency range configured information for indicating the target frequency bands to the receiving terminal.

Specifically, when ONU#l networks, registration request can be sent to OLT, to ask the communication resource used within the first period（Frequency range in system bandwidth）, also, the device identification of the ONU#l can be carried in the registration request, the device identification can uniquely indicate the ONU#l in systems, for example, it may be ONU#l sequence number（SN, Serial Number) or MAC Address etc..

OLT is received after the registration request, can from system bandwidth for the ONU#l distribute one The frequency range only used in first period for the ONU#l（One of target frequency bands）, non-limiting as example, the frequency range can be 0.6GHz ~ 0.8GHz (following, to be denoted as frequency range #1).

Thereafter, OLT can be by, for example, broadcast message etc., will indicate that the device identification of the frequency range #1 information and ONU#l is sent to each ONU (including ONU#l), so that, ONU#l can be according to its device identification, it is determined that frequency range #1 can be used to be communicated.It should be noted that other ONU in system can forbid being communicated using frequency range #1 within the first period when it is determined that device identification corresponding with frequency range #1 is different with its own device identification.

It should be understood that, the method of salary distribution of target frequency bands listed above is merely illustrative, for example, first period can be the ONU#l it is whole net the period, or or periodically the period, for example, using time-multiplexed mode, a periods of the ONU#l in a cycle is communicated using frequency range #1, make be communicated using frequency range #1 another period of other ONU in same period.

So as to which OLT can be defined as the frequency range #1 (0.6GHz ~ 0.8GHz) of ONU#l distribution, belong to the second Nyquist domain（0.5GHz ~ lGHz), and then can determine that (one of target DAC, the feature Nyquist domain corresponding to target DAC is the second Nyquist domain using DAC#2）Digital-to-analogue conversion processing is carried out to the target number signal.

Really the method for the DAC according to embodiments of the present invention that sets the goal, by making ONU initiate register flow path to OLT in networking, the ONU that OLT can be made to service as needed adjusts used DAC quantity, in ONU negligible amounts, unnecessary DAC equipment can be closed, communications cost can be saved, energy-conserving and environment-protective are realized.Also, because OLT can control the distribution of frequency range in real time, the change of network element can be flexibly tackled, communication strategy is adjusted.

Mode B

The transmitting terminal obtains mapping item, and the mapping item records the mapping relations between the receiving terminal and the target frequency bands；

The transmitting terminal searches the mapping item according to the receiving terminal, to determine the target frequency bands；The transmitting terminal determines target DAC according to the target frequency bands.

Specifically, for example, frequency range used in each ONU can also be allocated by network manager or operator, OLT can obtain record from network manager or operator the mapping item of the mapping relations between each ONU and each frequency range.

So as to, ONU#l network or ask communication when, OLT can according to search the mapping item, To determine the frequency range #1 corresponding with the ONU#l, and then frequency range #1 (for example, 0.6GHz ~ 0.8GHz) is determined, belong to the second Nyquist domain（0.5GHz ~ lGHz), and then can determine to carry out digital-to-analogue conversion processing to the target number signal using DAC#2.

It should be noted that in embodiments of the present invention, when OLT is that each ONU distributes communications band, a frequency range can be made to only belong to a Nyquist domain, so as to avoid because a frequency range overstates two Nyquist domains and caused by aliasing, make performance degradation, demodulation will be unable to when serious.And, OLT can be avoided to occur maloperation when selecting DAC, for example, if a part for a frequency range belongs to the 3rd Nyquist domain, another part belongs to the 4th Nyquist domain, in order to avoid interference, DAC#3 and DAC#4 can not be other ONU services, cause the waste of system resource.

So as to which in S130, OLT can use DAC#2 (one of target DAC determined as described above）, digital-to-analogue conversion processing is carried out to target number signal, the processing procedure can be with same as the prior art or similar, and here, in order to avoid repeating, description is omitted.As described above, the analog signal for handling and generating via the DAC#2（In other words, Nyquist signal, i.e. one of target simulation signal）Maximum output intensity be located at the second Nyquist domain, i.e. signal to noise ratio of the target simulation signal in the second Nyquist domain is maximum, signal quality preferably, so as to realize in high frequency（Non- first Nyquist domain）Signal transmission.

Alternatively, before the transmitting terminal sends the target simulation signal to the receiving terminal, this method also includes：

The transmitting terminal carries out the first filtering process, with the part in the feature Nyquist domain in the target frequency bands or target DAC for only retaining the target simulation signal.

Specifically, in each Nyquist domain there is component from the DAC#2 analog signals exported, in order to avoid the interference of the component in other Nyquist domains component positioned at second Nyquist domain best to signal quality, target simulation signal can be filtered by wave filter（One of first filtering；), only to retain the part in the second Nyquist domain of the echo signal, it is used as the mode of filtering, for example, it can be filtered according to scope of second Nyquist on frequency domain, i.e. only retain the part being between 0.5GHz ~ lGHz of target simulation signal.

It should be understood that; the method of filtering listed above is merely illustrative; other methods that can only retain the part in the feature Nyquist domain in target DAC of target simulation signal are each fallen within protection scope of the present invention; for example, it is also possible to be filtered according to the output intensity of target simulation signal.

In addition, in embodiments of the present invention, for example, ONU#l is communicated within the first period using frequency range #1, therefore, ONU#l is receiving the passband signal of OLT transmissions（That is, in system bandwidth Each ONU signal is multiplexed with, is then described in detail）Afterwards, the passband signal can be filtered according to frequency range #1, only to obtain the signal in the range of frequency range #1, is used as target simulation signal.Therefore, above-mentioned first filtering can also only retain the part in frequency range #1 of the echo signal, for example, can be filtered according to scopes of the frequency range #1 on frequency domain, i.e. only retain the part being between 0.6GHz ~ 0.8GHz of target simulation signal.

The transmitting terminal carries out the second filtering process, only to retain the target simulation signal in the feature Nyquist domain of the target frequency bands or target DAC.

Specifically, when within the first period, OLT is needed to other ONU in addition to ONU#l, for example, when ONU#2 sends signal, being communicated with ONU#2 within the first period using frequency range #2, frequency range #2 belongs to the 3rd Nyquist domain（Nyquist domain at DAC#3 maximum output intensity) exemplified by, the analog signal for handling and generating through DAC#3（Hereinafter referred to as interference signal）There is component in each Nyquist domain, target simulation signal is interfered in order to avoid the component positioned at the second Nyquist domain of the interference signal, interference signal can be filtered by wave filter（One of second filtering）To delete the component positioned at the second Nyquist domain of interference signal, in other words, only retain echo signal in the second Nyquist domain, as the mode of filtering, for example, it can be multiplexed by interference signal and echo signal to before system bandwidth, identical method is filtered using with above-mentioned first, interference signal is filtered, so as to remove the component being located in the second Nyquist domain or frequency range #1 of interference signal.

It should be understood that in embodiments of the present invention, the second filtering process can be carried out with the second filtering process simultaneously, i.e. when carrying out above-mentioned first filtering process to interference signal, equivalent to having carried out above-mentioned second filtering process.

In S140, OLT will can need to send in the first period to each ONU analog signal（Including target simulation signal）Multiplexing forms ofdm signal in whole system bandwidth.Also, OLT can carry out electro-optic conversion processing to the ofdm signal, form optical signal.So as to which OLT can be via Optical Distribution Network（ODN, Optical Distribution Network) optical signal is broadcasted to each ONU.

Situation 2

It is with the main distinction of above-mentioned situation 1, OLT and ONU#l carries out point to point link, i.e., ONU#l can use any frequency range in system bandwidth to be communicated, in the case of this, determine that target frequency bands and target DAC mode have differences with situation 1, below mainly above-mentioned distinctive points are said Bright, in the case of not specified, the action of other steps and method are similar to situation 1.

Alternatively, any frequency range that the receiving terminal can be at least two frequency range is communicated, and the transmitting terminal determines the target DAC corresponding with target frequency bands from least two DAC, including：

The transmitting terminal regard any DAC at least two DAC as target DAC;

The transmitting terminal determines the target frequency bands from the feature Nyquist domain corresponding to target DAC；And

This method also includes：

Specifically, the any frequency range in system bandwidth can be used to be communicated due to ONU#l, therefore, OLT can select any DAC as target DAC, for example, DAC#2 can be selected, it may thereby determine that the frequency range of generated target simulation signal belongs to the second Nyquist domain, so as to, for example, can be according to size of data signal etc., it is determined that the width of required target frequency bands, and determine that frequency range #1 is used as target frequency bands from the second Nyquist domain, and, it can will indicate the configured information of the target frequency bands, it is sent to ONU#l.

So as to which ONU#l according to the frequency range configured information, can determine the signaling bearer of OLT transmissions in frequency range #1.

Further, since OLT and ONU#l carries out point to point link, therefore in the absence of interference signal, without carrying out above-mentioned second filtering process.

Thus, OLT completes the transmission of the downlink data for ONU#l.Below, with ONU#l

(one of receiving terminal）Reception action exemplified by, the reception processing to receiving terminal is illustrated.

As it appears from the above, before ONU#l receives optical signal, the Deta bearer for needing to receive can be known in frequency range #1 (one of target frequency bands）.

So as to which ONU#l can carry out opto-electronic conversion processing to the optical signal, form analog signal after the optical signal of OLT transmissions is received（Electric signal）, for example, when the electric signal is the ofdm signal comprising the signal being carried in multiple frequency ranges（In the case of point-to-multipoint transmission）, ONU#l can be according to its target frequency bands, i.e. frequency range #1, and only selection is located at frequency range #1 signal from ofdm signal, i.e. OLT needs to be sent to ONU#l target simulation signal.

Or, ONU#l, can be according to its target frequency bands, i.e. frequency range #1 after the optical signal of full bandwidth of OLT transmissions is received, and the optical signal of the full bandwidth is filtered, so as to obtain the target optical signal being only carried on frequency range #1（It is corresponding with target simulation signal), and it is possible to the mesh Mark optical signal and carry out opto-electronic conversion processing, to obtain target simulation signal.

As described above, frequency range #1 is in the second Nyquist domain, therefore the target simulation signal is non-baseband signal.

In embodiments of the present invention, two kinds of methods handled the non-baseband signal can be provided.Method i

ONU#l can be for example, by the target simulation signal of the high frequency, in analog domain, is downconverted to base band by i/q demodulator, then carries out the analog-to-digital conversion sampling of low speed.

At that time, this method needs to use the i/q demodulator of high speed, the i/q demodulator of current high speed is difficult to obtain, cost is higher, in addition, because the same phase and orthogonal two branch road of i/q demodulator are inconsistent, the gain difference of frequency mixer causes amplitude imbalance, the phase difference of two local oscillation signals is not that strict 90 ° cause unbalance in phase, and there is the unbalanced problem of I/Q two-way, the change of baseband I/Q signal can be caused, I/Q imbalance problems are produced, ultimately result in performance degradation.

Method

When the feature Nyquist domain corresponding to target DAC is not the first Nyquist domain, this method also includes：

The transmitting terminal sends Nyquist domain configured information to the receiving terminal, and the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands.

Specifically, analog signal can be known in ONU#l（In other words, the DAC of analog signal maximum output intensity is generated）Present Nyquist domain, in other words, in the case of the pattern for generating the shock response curve that the DAC of the analog signal is used, ONU#l can be in base band（First Nyquist domain）In recover the component of the analog signal, i.e. in embodiments of the present invention, ONU#l can

Analog Digital Converter) carry out analog-to-digital conversion process.Fig. 3 is the schematic diagram for the frequency spectrum shift effect for representing Undersampling technique, as shown in figure 3, for 72.5 megahertzs（MHz) scholar 2MHz analog signal, if using baseband sampling, sampling rate need to be up to 145,000,000 sampling/second（MSPS, Million Samples Per Second) more than, but if using Undersampling technique, it is 10MSPS to make its sampling rate, it is possible to significantly reduce sampling rate.Also, for the input signal of a Bandwidth-Constrained, all there are two components at each harmonic of sample frequency（NFs + fa、 NFs - fa, N=0, 1 , 2……）.No matter input signal, on the premise of ensureing not occur spectrum overlapping after sampling processing, the frequency spectrum of the input signal of federation's existence anduniquess or the component of input signal (specifically, are image frequency components in Nyquist Bandwidth）, their all information of band comprising input signal.Therefore, it is Do not occur the overlapping of frequency spectrum in analog-to-digital conversion（), Overlap sample rate Fs, signal highest frequency FH, signal low-limit frequency FL to ADC needs to meet following condition：

2FH/K < Fs < 2FL/[k - 1]

2 < K < 2FH/[FH - FL] , FH < 2FL

The Nyquist domain at the maximum output intensity of analog signal is known in ONU#l, in other words, after the pattern for generating the shock response curve that the DAC of the analog signal is used, by base band（First Nyquist domain）The component of the signal is recovered, target number signal can be recovered with relatively low sampling rate.Without carrying out down coversion in analog domain.

Therefore, in embodiments of the present invention, OLT can notify ONU#l to send the Nyquist domain indicated at frequency range #1 after target DAC is determined（One of Nyquist domain configured information), or, the pattern of shock response curve used in ONU#l targets DAC can be notified（One of Nyquist domain configured information), or, the Nyquist domain at the maximum output intensity for the target simulation signal that ONU#l generated can be notified（Another example of Nyquist domain configured information）.

It should be noted that, in the case where OLT carries out above-mentioned first filtering process to target simulation signal, because the analog signal after first filtering process only exists in target DAC feature Nyquist domain, therefore, the Nyquist domain configured information can also indicate that the Nyquist domain at the target simulation signal.

The method of transmission data according to embodiments of the present invention, by making Nyquist domain of the receiving terminal according at the maximum output of analog signal, the component of the analog signal is recovered in a base band and the component is sampled, to obtain data signal, the sampling rate of the analog-to-digital conversion process of receiving terminal can be substantially reduced, further reduction communication equipment and the cost of networking.

After data signal is obtained as described above, ONU#l can carry out OFDM demodulation to the data signal, for example, it is y that data signal can be carried out to serioparallel exchange_eP= [ _& ..., 』^Τ, reject

After CP for y=[χ ο, Χ ι, Υ Ν-Α pass through Fast Fourier Transform (FFT)（FFT, Fast Fourier Transform) OFDM demodulation is completed, recover the modulated signal Y of each subcarrier=[Y, Y_NThe relevant treatment such as equilibrium is carried out after-A, then demodulate by corresponding QAM recover the data b of transmission=[..., J^T.The data frame transmitted finally by recovering to start after a parallel-serial conversion.And the processing such as solution frame, framing is carried out for example, by MAC module, finally by user to network interface（UNI, User to Network Interface), give terminal user by the data.

Fig. 4 is the schematic interaction figure of the method for transmission data according to an embodiment of the invention.As shown in Fig. 4, in S210, OLT can be according to the DAC configured quantity（In other words, it can use The quantity of the pattern of shock response curve）, system bandwidth is divided into multiple（Width is identical or different）Frequency range, because the sampling rate that each DAC is used is identical, distribution of each Nyquist domain formed in system bandwidth is identical, so that in embodiments of the present invention, OLT can make each frequency range only belong to a Nyquist domain.It should be noted that Nyquist domain can include a frequency range, can also multiple frequency ranges, the present invention is simultaneously not particularly limited.

In S215, OLT can be for example, by, base-band resource, periodically（To each ONU) broadcast SN requests.

In S220, ONU#l sends registration request after SN requests are received to OLT, also, carries in the registration request ONU#l SN.

In S225, OLT is received after the registration request, can be ONU#l one target frequency bands of distribution from each frequency range divided as described above（For example, above-mentioned frequency range #1), and message is indicated by frequency range, notify that ONU#l is communicated using the target frequency bands, also, ONU#l SN is carried in frequency range instruction message.

In S230, ONU#l determines that the frequency range indicates SN and the SN-cause of its own carried in message, so that it is determined that being communicated using target frequency bands.

In S235, ONU#l returns to a confirmation message to OLT, to notify OLT to be communicated by target frequency bands with ONU#l.

In S240, OLT descending training sequence is sent by the target frequency bands to ONU#l；

In S245, ONU#l calculates the signal to noise ratio of descending each subcarrier, and then determines the order of modulation of descending each subcarrier.

OLT will be sent in S250, ONU#l for descending result of calculation and up training sequence.In S255, OLT calculates the signal to noise ratio of up each subcarrier, and then determines the order of modulation of up each subcarrier.

In S260, OLT will be sent to ONU#l for up result of calculation, and confirm to set successfully.In S265, ONU#l confirms to set successfully to OLT.

In S270, subsequent registration flow is completed, for example, ONU ID are distributed, ranging etc..

In S275, carried out data transmission using above-mentioned target frequency bands.

It should be understood that the embodiment that the method for the transmission signal of the present invention is applied to PON is enumerated above, but the present invention is not limited to this, various communication systems can also be applied to, for example, global system for mobile communications（GSM, Global System of Mobile communication), CDMA（CDMA, Code Division Multiple Access) system, WCDMA（ WCDMA, Wideband Code Division Multiple Access Wireless), GPRS (GPRS, General Packet Radio Service), Long Term Evolution (LTE, Long Term Evolution) etc..

Also, need to be transmitted by optical signal in PON, but the present invention is not limited to this, after transmitting terminal generation target simulation signal, can also directly send it to receiving terminal.

The method of transmission signal according to embodiments of the present invention, by configuring multiple DAC in transmitting terminal, the maximum output intensity of the analog signal after being handled through each DAC is set to be located at different Nyquist domains, and be that each receiving terminal distributes different frequency ranges in system bandwidth, transmitting terminal to receiving terminal when sending data, according to the Frequency Band Selection target DAC corresponding with the receiving terminal, so that target frequency bands belong to the Qwest domain at target DAC maximum output intensity, and to target DAC to needing the data for being sent to the receiving terminal to handle, to generate target simulation signal, and then it is sent to the receiving terminal, so as to which receiving terminal can be according to its corresponding frequency range, target simulation signal is recognized from system bandwidth, therefore, respectively

DAC sample rate so as to reduce the requirement to DAC sample rates, and then reduces the cost of communication equipment and networking without corresponding with system bandwidth.

Fig. 5 is the indicative flowchart of the method 300 of transmission data according to an embodiment of the invention.The receiving terminal of target number signal at least one receiving terminal that this method 300 is included by communication system is performed, the communication system also includes transmitting terminal, the transmitting terminal has at least two digital-to-analogue conversion DAC, the sample rate that at least two DAC is used is identical, and the feature Nyquist domain of at least two DAC is different each other, wherein, one DAC feature Nyquist domain is the Nyquist domain at the maximum output intensity of the analog signal generated through the processing of the DAC, the system bandwidth that the communication system is used is divided at least two frequency ranges, one frequency range only belongs to DAC feature Nyquist domain, and the frequency range is only used for the communication of the receiving terminal in a period, as shown in Figure 5, this method 300 includes：

S310, the receiving terminal determines target frequency bands, and the target frequency bands, which are the transmitting terminals, with the receiving terminal communicate the frequency range used；

S320, the receiving terminal obtains the target simulation signal of transmitting terminal transmission according to the target frequency bands；

S330, the receiving terminal receives the Nyquist domain configured information of transmitting terminal transmission, and the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands；

S340, the receiving terminal determines respective components of the target simulation signal in the first Nyquist domain according to the Nyquist domain configured information；

S350, respective components of the receiving terminal according to the target simulation signal in the first Nyquist domain carry out analog-to-digital conversion process to the target simulation signal.. Technical scheme, can apply to it is various need to make transmitting terminal convert digital signals into analog signal, and by the way of radio communication or optic communication, the analog signal is sent to the communication system of receiving terminal, for example：In pon, PON local sides are with a trunk optical fiber, you can be divided into tens of even more multi-channel optical fibres connection users, substantially reduce networking cost.Current PON technologies mainly have EPON and GPON etc. several, and its Main Differences is to employ two layers of different technologies.Existing EPON and GPON products can be using different technologies schemes such as OFDM-PON.OFDM-PON technologies can not only introduce transmitting terminal and receiving terminal Electric signal processing to eliminate various damages, may be incorporated into high order modulation reduces the bandwidth requirement of various photoelectric devices, in addition the technology also has the advantages that the multiple access access of high efficient and flexible and resource allocation methods, therefore has obtained industry and widely pay close attention to.

In pon, OLT can be communicated to connect with one or more ONU, also, an ONU can use PON system bandwidth（In other words, system carrier）In a part of frequency range（In other words, subcarrier）Communicated, in PON downlink transmission process, OLT needs the data by each ONU is sent to, and then multi-carrier modulation to whole system bandwidth is broadcasted to each ONU.

Hereinafter, for the ease of understanding and illustrating, the method 300 of the transmission signal of the embodiment of the present invention is applied to process during PON（Specifically, it is downlink transmission process）Exemplified by, illustrate, in this case, OLT is equivalent to transmitting terminal, ONU is equivalent to receiving terminal.

In embodiments of the present invention, OLT can be communicated to connect with multiple ONU, also, the frequency range in system bandwidth used in communications of each ONU within the same period is different（That is, situation 3), or, OLT can be communicated to connect with ONU, also, the ONU within a period can use system bandwidth in any frequency range（The width of the frequency range is less than system bandwidth）Communicated（That is, situation 4) below, the action in the case of both the above is illustrated respectively respectively.

Situation 3

OLT (one of transmitting terminal）The data flow frame for needing to be sent to coupled multiple ONU can be obtained from NNI, and it is possible to for example, by MAC module carries out solution frame, the framing procedure for above-mentioned data flow frame.So as to for example, can distinguish needs according to the destination address of the MAC layer of each data flow frame and be sent to for example, ONU#l (one of receiving terminal）Data, thereafter, can to the data carry out OFDM modulation, so as to generate real number OFDM baseband signals（One of target number signal）.

In embodiments of the present invention, OLT can be configured with multiple（At least two）DAC, also, each DAC sample rate is identical, so that, identical for each DAC position and dividing mode of the Nyquist domain in system bandwidth, specifically, the quantity in each DAC Nyquist domain is identical, also, respectively Nyquist domain corresponding frequency range in system bandwidth is identical.If for example, as shown in Fig. 2 each DAC sample rate is 1GSPS, the width in a Nyquist domain is 0.5GHz, if in this case, system bandwidth is 3GHz, needing 6 Nyquist domains.

Also, in embodiments of the present invention, the pattern for the shock response curve that each DAC is used is different, so that, the Nyquist domain at maximum output intensity respectively through the DAC analog signals handled（That is, feature Nyquist domain）It is different each other, as shown in Figure 2, use NRZ MODE, the DAC of Non Return to Zero MODE shock response curve is (following, be denoted as DAC#1) signal output intensity maximum in the first Nyquist domain, it is (following using the DAC of RF MODE shock response curve, be denoted as DAC#2) signal output intensity maximum in the second Nyquist domain, it is (following using the DAC of RZ MODE shock response curve, be denoted as DAC#3) signal output intensity maximum in the 3rd Nyquist domain, it is (following using the DAC of RFZ MODE shock response curve, be denoted as DAC#4) signal output intensity maximum in the 4th Nyquist domain.I.e., in embodiments of the present invention, the analog signal generated through each DAC processing is different each other（Specifically, the Nyquist domain at maximum output intensity is different）.

As described above, system bandwidth is divided into multiple frequency ranges, multiple ONU are communicated in a period using only a frequency range, and OLT can determine that ONU#l uses frequency range.In embodiments of the present invention, mode A

Alternatively, the receiving terminal determines target frequency bands, including：

The receiving terminal receives the frequency range configured information for being used to indicate the target frequency bands of transmitting terminal transmission, and the target frequency bands are that the transmitting terminal is distributed from least two frequency range for the receiving terminal；

The receiving terminal determines the target frequency bands according to the frequency range configured information.

Also, the receiving terminal receive the transmitting terminal transmission be used for indicate the frequency range configured information of the target frequency bands before, this method also includes：

The receiving terminal sends registration request to the transmitting terminal, in order to which the transmitting terminal distributes the target frequency bands from least two frequency range according to the registration request for the receiving terminal, and sends the frequency range configured information.

Specifically, in ONU#l (one of receiving terminal）, can be to OLT (one of transmitting terminal during networking）Registration request is sent, to ask the communication resource used within the first period（In system bandwidth Frequency range）, also, the device identification of the ONU#l can be carried in the registration request, the device identification can uniquely indicate the ONU#l in systems, for example, it may be ONU#l sequence number（SN, Serial Number) or MAC Address etc..

OLT is received after the registration request, can be that the ONU#l distributes a frequency range only used within the first period for the ONU#l from system bandwidth（One of target frequency bands), non-limiting as example, the frequency range can be 0.6GHz ~ 0.8GHz (following, to be denoted as frequency range #1).

It should be understood that, the method of salary distribution of target frequency bands listed above is merely illustrative, for example, first period can be the whole in the net period of the ONU#l, or or periodically the period, for example, using time-multiplexed mode, make a periods of the ONU#l in a cycle（First period）Communicated using frequency range #1, make be communicated using frequency range #1 another period of other ONU in same period.

So as to which OLT can be defined as the frequency range #1 (0.6GHz ~ 0.8GHz) of ONU#l distribution, belong to the second Nyquist domain（0.5GHz ~ lGHz), and then can determine to carry out digital-to-analogue conversion processing to the target number signal using DAC#2 (one of target DAC).

Set the goal DAC method really according to embodiments of the present invention, by make ONU in networking to

OLT initiates register flow path, and the ONU that OLT can be made to service as needed adjusts used DAC quantity, in ONU negligible amounts, can close unnecessary DAC equipment, can save communications cost, realize energy-conserving and environment-protective.Also, because OLT can control the distribution of frequency range in real time, the change of network element can be flexibly tackled, communication strategy is adjusted.

Mode B

The receiving terminal obtains mapping item, and mapping item record has the mapping relations between the receiving terminal and the target frequency bands；

The receiving terminal searches the mapping item, to determine the target frequency bands

Specifically, for example, frequency range used in each ONU can also be allocated by network manager or operator, ONU#l can obtain record from network manager or operator has each ONU and each The mapping item of mapping relations between frequency range.

So as to which when ONU#l networks or asks communication, the mapping item can be searched, to determine the frequency range #1 corresponding with the ONU#l.

Similarly, OLT can also be obtained and be searched the mapping item, to determine the frequency range #1 corresponding with the ONU#l, and then determined frequency range #1 (for example, 0.6GHz ~ 0.8GHz), belonged to the second Nyquist domain（0.5GHz ~ lGHz), and then can determine to carry out digital-to-analogue conversion processing to the target number signal using DAC#2.

So as to which OLT can use the DAC#2 (one of target DAC) determined as described above, and digital-to-analogue conversion processing is carried out to target number signal, the processing procedure can be with same as the prior art or similar, here, in order to avoid repeating, description is omitted.As described above, the analog signal for handling and generating via the DAC#2（In other words, Nyquist signal, i.e. one of target simulation signal）Maximum output intensity be located at the second Nyquist domain, i.e. signal to noise ratio of the target simulation signal in the second Nyquist domain is maximum, signal quality preferably, so as to realize in high frequency（Non- first Nyquist domain）Signal transmission.

It should be noted that, in each Nyquist domain there is component from the DAC#2 analog signals exported, in order to avoid the interference of the component in other Nyquist domains component positioned at second Nyquist domain best to signal quality, target simulation signal can be filtered by wave filter（One of first filtering；), only to retain the part in the second Nyquist domain of the echo signal, it is used as the mode of filtering, for example, it can be filtered according to scope of second Nyquist on frequency domain, i.e. only retain the part being between 0.5GHz ~ lGHz of target simulation signal.

In addition, when within the first period, OLT is needed to other ONU in addition to ONU#l, for example, when ONU#2 sends signal, being communicated with ONU#2 within the first period using frequency range #2, frequency range #2 belongs to the 3rd Nyquist domain（Nyquist domain at DAC#3 maximum output intensity）Exemplified by, the analog signal for handling and generating through DAC#3（Hereinafter referred to as interference signal）There is component in each Nyquist domain, target simulation signal is interfered in order to avoid the component positioned at the second Nyquist domain of the interference signal, interference signal can be filtered by wave filter（One of second filtering）To delete the component positioned at the second Nyquist domain of interference signal, in other words, only retain echo signal in the second Nyquist domain, as the mode of filtering, for example, it can be multiplexed by dry 4 outstanding signals and echo signal to before system bandwidth, identical method is filtered using with above-mentioned first, interference signal is filtered, so as to remove the component being located in the second Nyquist domain or frequency range #1 of interference signal.

Thereafter, OLT will can need to send in the first period to each ONU analog signal（Including target simulation signal）Multiplexing forms ofdm signal in whole system bandwidth.Also, OLT can carry out electro-optic conversion processing to the ofdm signal, form optical signal.So as to which OLT can broadcast optical signal to each ONU via Optical Distribution Network (ODN, Optical Distribution Network).

Situation 4

It is with the main distinction of above-mentioned situation 3, OLT and ONU#l carries out point to point link, i.e., ONU#l can use any frequency range in system bandwidth to be communicated, in this case, determine that target frequency bands and target DAC mode have differences with situation 3, below mainly above-mentioned distinctive points are illustrated, in the case of not specified, the action of other steps and method are similar to situation 3.

The receiving terminal determines the target frequency bands according to the frequency range configured information. Specifically, the any frequency range in system bandwidth can be used to be communicated due to ONU#l, therefore, OLT can select any DAC as target DAC, for example, DAC#2 can be selected, it may thereby determine that the frequency range of generated target simulation signal belongs to the second Nyquist domain, so as to, for example, can be according to size of data signal etc., it is determined that the width of required target frequency bands, and determine that frequency range #1 is used as target frequency bands from the second Nyquist domain, and, it can will indicate the configured information of the target frequency bands, it is sent to ONU#l.

Thus, OLT completes the transmission of the downlink data for ONU#l.Below, with ONU#l (one of receiving terminal）Reception action exemplified by, the reception processing to receiving terminal is illustrated.

As it appears from the above, before ONU#l receives optical signal, in S310, ONU#l can know the Deta bearer for needing to receive in frequency range #1 (one of target frequency bands).

In S320, ONU#l opto-electronic conversion processing can be carried out to the optical signal, form analog signal（Electric signal）, for example, when the electric signal is the ofdm signal comprising the signal being carried in multiple frequency ranges (in the case of point-to-multipoint transmission）, ONU#l can be according to its target frequency bands, i.e. frequency range #1, and only selection is located at frequency range #1 signal from ofdm signal, i.e. OLT needs to be sent to ONU#l target simulation signal.

Or, ONU#l, can be according to its target frequency bands, i.e. frequency range #1 after the optical signal of full bandwidth of OLT transmissions is received, and the optical signal of the full bandwidth is filtered, so as to obtain the target optical signal being only carried on frequency range #1（It is corresponding with target simulation signal), and it is possible to opto-electronic conversion processing be carried out to the target optical signal, to obtain target simulation signal.

In S330, ONU#l can carry out analog-to-digital conversion process to the target simulation signal, to reduce the data frame from network side.

In S340, ONU#l can receive the Nyquist domain configured information of OLT transmissions, so that, ONU#l can know target frequency（In other words, the DAC of analog signal maximum output intensity is generated）Present Nyquist domain, and then, ONU#l can be in base band（First Nyquist domain）In recover the component of the analog signal, i.e. in embodiments of the present invention, ONU#l can be using owing Sampling（Also referred to as bandpass sampling or Intermediate Frequency Sampling）, pass through analog-digital converter（ADC, Analog Digital Converter) carry out analog-to-digital conversion process.Fig. 3 is the schematic diagram for the frequency spectrum shift effect for representing Undersampling technique, as shown in Figure 3, for 72.5MHz ± 2MHz analog signal, if utilizing baseband sampling, then sampling rate need to be up to more than 145MSPS, but if using Undersampling technique, it is 10MSPS to make its sampling rate, it is possible to significantly reduce sampling rate.Also, for the input signal of a Bandwidth-Constrained, all there are two components at each harmonic of sample frequency（NFs + fa、 NFs - fa, N=0, 1 , 2……）.No matter input signal, on the premise of ensureing not occur spectrum overlapping after sampling processing, the frequency spectrum of the input signal of federation's existence anduniquess or the component of input signal in Nyquist Bandwidth（Specifically, it is image frequency components）, their all information of band comprising input signal.Therefore, in order to not occur the overlapping of frequency spectrum in analog-to-digital conversion（), Overlap sample rate Fs, signal highest frequency FH, signal low-limit frequency FL to ADC needs to meet following condition：

2FH/K < Fs < 2FL/[k - 1]

2 < K < 2FH/[FH - FL] , FH < 2FL

Therefore, in embodiments of the present invention, OLT can also notify the Nyquist domain at the ONU#l target frequencies after target DAC is determined（One of Nyquist domain configured information), or, shock response curve used in target DAC pattern（Another example of Nyquist domain configured information）, or, the Nyquist domain at the maximum output intensity of the target simulation signal（Another example of Nyquist domain configured information）.

In S350, after data signal is obtained as described above, ONU#l can be carried out to the data signal OFDM demodulation, recovers the data frame that originator is transmitted.And the processing such as solution frame, framing is carried out for example, by MAC module, finally by UNI, terminal user is given by the data.

Fig. 4 is the schematic interaction figure of the method for transmission data according to an embodiment of the invention.As shown in Fig. 4, in S210, OLT can be according to the DAC configured quantity（In other words, the quantity of the pattern for the shock response curve that can be used）, system bandwidth is divided into multiple（Width is identical or different）Frequency range, because the sampling rate that each DAC is used is identical, distribution of each Nyquist domain formed in system bandwidth is identical, so that in embodiments of the present invention, OLT can make each frequency range only belong to a Nyquist domain.It should be noted that Nyquist domain can include a frequency range, can also multiple frequency ranges, the present invention is simultaneously not particularly limited.

In S215, OLT can be for example, by, base-band resource, periodically（To each ONU) broadcast

SN is asked.

In S275, carried out data transmission using above-mentioned target frequency bands. It should be understood that the embodiment that the method for the transmission signal of the present invention is applied to PON is enumerated above, but the present invention is not limited to this, various communication systems can also be applied to, for example, global system for mobile communications（GSM, Global System of Mobile communication), CDMA（CDMA, Code Division Multiple Access) system, WCDMA（WCDMA, Wideband Code Division Multiple Access Wireless), GPRS（GPRS, General Packet Radio Service), Long Term Evolution (LTE, Long Term Evolution) etc..

The method of transmission signal according to embodiments of the present invention, by configuring multiple DAC in transmitting terminal, the maximum output intensity of the analog signal after being handled through each DAC is set to be located at different Nyquist domains, and be that each receiving terminal distributes different frequency ranges in system bandwidth, transmitting terminal to receiving terminal when sending data, according to the Frequency Band Selection target DAC corresponding with the receiving terminal, so that target frequency bands belong to the Qwest domain at target DAC maximum output intensity, and to target DAC to needing the data for being sent to the receiving terminal to handle, to generate target simulation signal, and then it is sent to the receiving terminal, so as to which receiving terminal can be according to its corresponding frequency range, target simulation signal is recognized from system bandwidth, therefore, each DAC sample rate is without corresponding with system bandwidth, so as to reduce the requirement to DAC sample rates, and then reduce the cost of communication equipment and networking.

More than, the method that transmission signal according to embodiments of the present invention is described in detail with reference to Fig. 1 to Fig. 5, below, describe the device of transmission signal according to embodiments of the present invention in detail with reference to Fig. 6 to Fig. 7.

Fig. 6 shows the schematic block diagram of the device 400 of transmission signal according to embodiments of the present invention.The device 400 includes：

At least two digital analog converter DAC, feature Nyquist domain respectively corresponding to the DAC is different, wherein, this feature Nyquist domain is the processing through corresponding DAC and the Nyquist domain at the maximum output intensity of analog signal that generates, the sample rate that at least two DAC is used is identical, the system bandwidth that the communication system is used is divided at least two frequency ranges, and the frequency range belongs to the feature Nyquist domain corresponding to a DAC；

Acquiring unit 410, needs to be sent to the target number signal of receiving terminal for obtaining；

Determining unit 420, for determining the target DAC corresponding with target frequency bands from least two DAC, wherein, the target frequency bands to be the device with the receiving terminal the communicate frequency range used, the target frequency bands belong to the feature Nyquist domain corresponding to target DAC；

Generation unit 430, for being handled by target DAC the target number signal, with Generate target simulation signal；

Transmit-Receive Unit 440, for by the target frequency bands, the target simulation signal to be sent to the receiving terminal.Alternatively, when the feature Nyquist domain corresponding to target DAC is not the first Nyquist domain, the Transmit-Receive Unit 440 is additionally operable to send Nyquist domain configured information to the receiving terminal, and the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands.

Alternatively, the Transmit-Receive Unit 440 is additionally operable to receive the registration request that the receiving terminal is sent；The determining unit 420 is additionally operable to according to the registration request, from least two frequency range, and the target frequency bands are distributed for the receiving terminal, and ^ determines target according to the target frequency bands from least two DAC

DAC;

The Transmit-Receive Unit 440 is additionally operable to send frequency range configured information for indicating the target frequency bands to the receiving terminal, in order to which the receiving terminal is according to the frequency range configured information, determines the target frequency bands.

Alternatively, the acquiring unit 410 is additionally operable to obtain mapping item, and mapping item record has the mapping relations between each receiving terminal and each frequency range；

The determining unit 420 to determine the target frequency bands, and occupies the target frequency bands, determines target DAC specifically for according to the receiving terminal, searching the mapping item.

Alternatively, the receiving terminal can be at least two frequency range any frequency range communicated, and the determining unit 420 using any DAC at least two DAC specifically for, as target DAC, and from target DAC feature Nyquist domain, determining the target frequency bands；

Alternatively, the generation unit 430 is additionally operable to carry out the first filtering process, only to retain the part in the feature Nyquist domain corresponding to the target frequency bands or target DAC of the target simulation signal.

Alternatively, the generation unit 430 is additionally operable to carry out the second filtering process, only to retain the target simulation signal in the feature Nyquist domain corresponding to the target frequency bands or target DAC

The transmitting terminal that the device 400 of transmission signal according to embodiments of the present invention may correspond in the method for the embodiment of the present invention（For example, OLT), also, each unit in the device 400 be module and other above-mentioned operation and/or functions respectively in order to realize the corresponding flow of the method 100 in Fig. 1, in order to which cylinder is clean, will not be repeated here.

The device of transmission signal according to embodiments of the present invention, by configuring multiple DAC in transmitting terminal, the maximum output intensity of the analog signal after being handled through each DAC is set to be located at different Nyquist domains, and be that each receiving terminal distributes different frequency ranges in system bandwidth, transmitting terminal to receiving terminal when sending data According to the Frequency Band Selection target DAC corresponding with the receiving terminal, so that target frequency bands belong to the Qwest domain at target DAC maximum output intensity, and to target DAC to needing the data for being sent to the receiving terminal to handle, to generate target simulation signal, and then it is sent to the receiving terminal, so as to which receiving terminal can be according to its corresponding frequency range, target simulation signal is recognized from system bandwidth, therefore, each DAC sample rate is without corresponding with system bandwidth, so as to reduce the requirement to DAC sample rates, and then reduce the cost of communication equipment and networking.

Fig. 7 shows the schematic block diagram of the device 500 of transmission signal according to embodiments of the present invention.The device 500 includes：

Determining unit 510, for determining target frequency bands, the target frequency bands, which are transmitting terminals, with the device communicate the frequency range used；

Transmit-Receive Unit 520, for according to the target frequency bands, the target simulation signal of transmitting terminal transmission is obtained, and receives the Nyquist domain configured information of transmitting terminal transmission, the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands；

Processing unit 530, for according to the Nyquist domain configured information, determine respective components of the target simulation signal in the first Nyquist domain, and the respective components according to the target simulation signal in the first Nyquist domain, analog-to-digital conversion process is carried out to the target simulation signal, to obtain the target number signal.

Alternatively, the Transmit-Receive Unit 520 is additionally operable to receive the frequency range configured information for being used to indicate the target frequency bands that the transmitting terminal is sent, and the target frequency bands are that the transmitting terminal is distributed from least two frequency range for the receiving terminal；

The determining unit 510 is specifically for according to the frequency range configured information, determining the target frequency bands.

Alternatively, the Transmit-Receive Unit 520, which is additionally operable to receive to the transmitting terminal, sends registration request, in order to which the transmitting terminal distributes the target frequency bands from least two frequency range according to the registration request for the receiving terminal, and sends the frequency range configured information.

Alternatively, the Transmit-Receive Unit 520, which is additionally operable to receive, obtains mapping item, and mapping item record has the mapping relations between each receiving terminal and each frequency range；

The determining unit 510 is specifically for searching the mapping item, to determine the target frequency bands.

The receiving terminal that the device 500 of transmission signal according to embodiments of the present invention may correspond in the method for the embodiment of the present invention（For example, ONU#l), also, each unit in the device 500 be module and other above-mentioned operation and/or functions respectively in order to realize the corresponding flow of the method 300 in Fig. 5, in order to which cylinder is clean, will not be repeated here. The device of transmission signal according to embodiments of the present invention, by configuring multiple DAC in transmitting terminal, the maximum output intensity of the analog signal after being handled through each DAC is set to be located at different Nyquist domains, and be that each receiving terminal distributes different frequency ranges in system bandwidth, transmitting terminal to receiving terminal when sending data, according to the Frequency Band Selection target DAC corresponding with the receiving terminal, so that target frequency bands belong to the Qwest domain at target DAC maximum output intensity, and to target DAC to needing the data for being sent to the receiving terminal to handle, to generate target simulation signal, and then it is sent to the receiving terminal, so as to which receiving terminal can be according to its corresponding frequency range, target simulation signal is recognized from system bandwidth, therefore, each DAC sample rate is without corresponding with system bandwidth, so as to reduce the requirement to DAC sample rates, and then reduce the cost of communication equipment and networking.

And, by making Nyquist domain of the receiving terminal according at the maximum output of analog signal, the component of the analog signal is recovered in a base band and the component is sampled, to obtain data signal, the sampling rate of the analog-to-digital conversion process of receiving terminal can be substantially reduced, further reduction communication equipment and the cost of networking.

More than, the method that transmission signal according to embodiments of the present invention is described in detail with reference to Fig. 1 to Fig. 5, below, describe the device of transmission signal according to embodiments of the present invention in detail with reference to Fig. 8 to Fig. 9.

Fig. 8 shows the schematic block diagram of the equipment 600 of transmission signal according to embodiments of the present invention.The equipment 600 has at least two digital analog converter DAC, feature Nyquist domain respectively corresponding to the DAC is different, wherein, this feature Nyquist domain is the processing through corresponding DAC and the Nyquist domain at the maximum output intensity of analog signal that generates, the sample rate that at least two DAC is used is identical, the system bandwidth that the communication system is used is divided at least two frequency ranges, one frequency range belongs to the feature Nyquist domain corresponding to a DAC, as shown in figure 8, the equipment 600 includes：

Bus 610;

The processor 620 being connected with the bus 610;

The memory 630 being connected with the bus 610;

The transceiver 640 being connected with the bus 610

Wherein, the processor 620 calls the program stored in the memory 630 by the bus 610, needs to be sent to the target number signal of receiving terminal for obtaining；

For determining the target DAC corresponding with target frequency bands from least two DAC, wherein, the target frequency bands are that the transmitting terminal communicates the frequency range used with receiving terminal progress, and the target frequency bands belong to the feature Nyquist domain corresponding to target DAC；

For being handled by target DAC the target number signal, to generate target simulation letter Number；

For controlling transceiver 640 by the target frequency bands, the target simulation signal is sent to the receiving terminal.Alternatively, when target DAC feature Nyquist domain is non-first Nyquist domain, the processor 620 is additionally operable to control the transceiver 640 to send Nyquist domain configured information to the receiving terminal, and the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands.

Alternatively, the processor 620 is additionally operable to control the transceiver 640 to receive the registration request that the receiving terminal is sent；

For according to the registration request, from least two frequency range, the target frequency bands are distributed for the receiving terminal, and according to the target frequency bands, target DAC is determined from least two DAC;

For controlling the transceiver 640 to send the frequency range configured information for indicating the target frequency bands to the receiving terminal, in order to which the receiving terminal is according to the frequency range configured information, the target frequency bands are determined.

Alternatively, the processor 620 is additionally operable to control the transceiver 640 to obtain mapping item, and mapping item record has the mapping relations between each receiving terminal and each frequency range；

For according to the receiving terminal, searching the mapping item, to determine the target frequency bands, and according to the target frequency bands, target DAC is determined.

Alternatively, the receiving terminal can be at least two frequency range any frequency range communicated, and the processor 620 using any DAC at least two DAC specifically for, as target DAC, and from target DAC feature Nyquist domain, determining the target frequency bands；

Alternatively, the processor 620 is additionally operable to carry out the first filtering process, only to retain the part in the feature Nyquist domain corresponding to the target frequency bands or target DAC of the target simulation signal.

Alternatively, the processor 620 is additionally operable to carry out the second filtering process, only to retain the target simulation signal in the feature Nyquist domain corresponding to the target frequency bands or target DAC.Each step and logic diagram opened.General processor 620 can be microprocessor or the processor can also be any conventional processor, decoder etc..The step of method with reference to disclosed in the embodiment of the present invention, can be embodied directly in hardware processor and perform completion, or perform completion with the hardware in decoding processor and software module combination.Software module can be located in random access memory, flash memory, read-only storage, the ripe storage medium in this area such as programmable read only memory or electrically erasable programmable memory, register.The storage medium is located at memory 630, and processor 620 reads the information in memory 630, knot Close the step of its hardware completes the above method.

It should be understood that in embodiments of the present invention, the processor 620 can be CPU（Central Processing Unit, cylinder is referred to as " CPU "), the processor 620 can also be other general processors, digital signal processor（DSP), application specific integrated circuit（ASIC), ready-made programmable gate array（) or other PLDs, discrete gate or transistor logic, discrete hardware components etc. FPGA.General processor can be microprocessor or the processor can also be any conventional processor etc..

The memory 630 can include read-only storage and random access memory, and provide instruction and data to processor 820.The a part of of memory 630 can also include nonvolatile RAM.For example, memory 630 can be with the information of storage device type.

The bus 610 can also include power bus, controlling bus and status signal bus in addition etc. in addition to including data/address bus.But for the sake of clear explanation, various buses are all designated as bus 610 in figure.

In implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware in processor 620 or the instruction of software form.The step of method with reference to disclosed in the embodiment of the present invention, can be embodied directly in hardware processor and perform completion, or perform completion with the hardware in processor and software module combination.Software module can be located in random access memory, flash memory, read-only storage, the ripe storage medium in this area such as programmable read only memory or electrically erasable programmable memory, register.The storage medium is located at memory 630, and processor 620 reads the information in memory 630, the step of completing the above method with reference to its hardware.To avoid repeating, it is not detailed herein.

The transmitting terminal that the equipment 600 of transmission signal according to embodiments of the present invention may correspond in the method for the embodiment of the present invention（For example, OLT), also, each unit in the equipment 600 be module and other above-mentioned operation and/or functions respectively in order to realize the corresponding flow of the method 100 in Fig. 1, in order to which cylinder is clean, will not be repeated here.

The equipment of transmission signal according to embodiments of the present invention, by configuring multiple DAC in transmitting terminal, the maximum output intensity of the analog signal after being handled through each DAC is set to be located at different Nyquist domains, and be that each receiving terminal distributes different frequency ranges in system bandwidth, transmitting terminal to receiving terminal when sending data, according to the Frequency Band Selection target DAC corresponding with the receiving terminal, so that target frequency bands belong to the Qwest domain at target DAC maximum output intensity, and to target DAC to needing the data for being sent to the receiving terminal to handle, to generate target simulation signal, and then it is sent to the receiving terminal, so as to which receiving terminal can be according to its corresponding frequency range, target simulation signal is recognized from system bandwidth, therefore, each DAC sample rate is without corresponding with system bandwidth, so as to reduce the requirement to DAC sample rates, and then reduce the cost of communication equipment and networking. Fig. 9 shows the schematic block diagram of the equipment 700 of transmission signal according to embodiments of the present invention.The equipment 700 includes：

As shown in Figure 10, the equipment 700 includes：

Bus 710;

The processor 720 being connected with the bus 710;

The memory 730 being connected with the bus 710;

The transceiver 740 being connected with the bus 710

Wherein, the processor 720 calls the program stored in the memory 730 by the bus 710, for determining target frequency bands, and the target frequency bands are the transmitting terminals to communicate the frequency range used with receiving terminal progress；

For according to the target frequency bands, control transceiver 740 to obtain the target simulation signal that the transmitting terminal is sent；

For controlling transceiver 740 to receive the Nyquist domain configured information that the transmitting terminal is sent, the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands；

For according to the Nyquist domain configured information, determining respective components of the target simulation signal in the first Nyquist domain；

For the respective components according to the target simulation signal in the first Nyquist domain, analog-to-digital conversion process is carried out to the target simulation signal.

Alternatively, the processor 720 is additionally operable to control the transceiver 740 to receive the frequency range configured information for being used to indicate the target frequency bands that the transmitting terminal is sent, and the target frequency bands are that the transmitting terminal is distributed from least two frequency range for the receiving terminal；

For according to the frequency range configured information, determining the target frequency bands.

Alternatively, the processor 720 is additionally operable to control the transceiver 740 to send registration request to the transmitting terminal, in order to which the transmitting terminal distributes the target frequency bands from least two frequency range according to the registration request for the receiving terminal, and sends the frequency range configured information.

Alternatively, the processor 720 is additionally operable to control the transceiver 740 to receive acquisition mapping item, and mapping item record has the mapping relations between each receiving terminal and each frequency range；

For searching the mapping item, to determine the target frequency bands.Each step and logic diagram opened.General processor 720 can be microprocessor or the processor can also be any conventional processor, decoder etc..The step of method with reference to disclosed in the embodiment of the present invention Hardware processor can be embodied directly in and perform completion, or completion is performed with the hardware in decoding processor and software module combination.Software module can be located in random access memory, flash memory, read-only storage, the ripe storage medium in this area such as programmable read only memory or electrically erasable programmable memory, register.The storage medium is located at memory 730, and processor 720 reads the information in memory 730, the step of completing the above method with reference to its hardware.

It should be understood that in embodiments of the present invention, the processor 720 can be CPU（Central Processing Unit, cylinder is referred to as " CPU "), the processor 720 can also be other general processors, digital signal processor（DSP), application specific integrated circuit（ASIC), ready-made programmable gate array（) or other PLDs, discrete gate or transistor logic, discrete hardware components etc. FPGA.General processor can be microprocessor or the processor can also be any conventional processor etc..

The memory 730 can include read-only storage and random access memory, and provide instruction and data to processor 820.The a part of of memory 730 can also include nonvolatile RAM.For example, memory 730 can be with the information of storage device type.

The bus 710 can also include power bus, controlling bus and status signal bus in addition etc. in addition to including data/address bus.But for the sake of clear explanation, various buses are all designated as bus 710 in figure.

In implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware in processor 720 or the instruction of software form.The step of method with reference to disclosed in the embodiment of the present invention, can be embodied directly in hardware processor and perform completion, or perform completion with the hardware in processor and software module combination.Software module can be located in random access memory, flash memory, read-only storage, the ripe storage medium in this area such as programmable read only memory or electrically erasable programmable memory, register.The storage medium is located at memory 730, and processor 720 reads the information in memory 730, the step of completing the above method with reference to its hardware.To avoid repeating, it is not detailed herein.

The receiving terminal that the equipment 700 of transmission signal according to embodiments of the present invention may correspond in the method for the embodiment of the present invention（For example, ONU#l), also, each unit in the equipment 700 be module and other above-mentioned operation and/or functions respectively in order to realize the corresponding flow of the method 300 in Fig. 5, in order to which cylinder is clean, will not be repeated here.

The equipment of transmission signal according to embodiments of the present invention, by configuring multiple DAC in transmitting terminal, the maximum output intensity of the analog signal after being handled through each DAC is set to be located at different Nyquist domains, and be that each receiving terminal distributes different frequency ranges in system bandwidth, transmitting terminal to receiving terminal when sending data, according to the Frequency Band Selection target DAC corresponding with the receiving terminal, so that target frequency bands belong to the Qwest domain at target DAC maximum output intensity, and this is sent to needs to target DAC The data of receiving terminal are handled, and to generate target simulation signal, and then the receiving terminal are sent to, so that receiving terminal can recognize target simulation signal, therefore, respectively according to its corresponding frequency range from system bandwidth

Figure 10 shows the schematic block diagram of the system 800 of transmission signal according to embodiments of the present invention, as shown in Figure 10, the system 800 includes transmitting terminal 810 and receiving terminal 820, the transmitting terminal 810 has at least two digital analog converter DAC, feature Nyquist domain respectively corresponding to the DAC is different, wherein, this feature Nyquist domain is the processing through corresponding DAC and the Nyquist domain at the maximum output intensity of analog signal that generates, the sample rate that at least two DAC is used is identical, the system bandwidth that the communication system is used is divided at least two frequency ranges, one frequency range belongs to the feature Nyquist domain corresponding to a DAC,

The transmitting terminal 810, which is used to obtain, to be needed to be sent to the target number signal of receiving terminal, the target DAC corresponding with target frequency bands is determined from least two DAC, wherein, the target frequency bands, which are the transmitting terminals, with the receiving terminal communicate the frequency range used, the target frequency bands belong to the feature Nyquist domain corresponding to target DAC, the target number signal is handled by target DAC, to generate target simulation signal, by the target frequency bands, the target simulation signal is sent to the receiving terminal；

Receiving terminal 820 is used to determine the target frequency bands, and according to the target frequency bands, obtains the target simulation signal of the transmitting terminal 810 transmission, analog-to-digital conversion process is carried out to the target simulation signal, to obtain the target number signal.

Alternatively, when target DAC feature Nyquist domain is non-first Nyquist domain, the transmitting terminal 810 is additionally operable to send Nyquist domain configured information to the receiving terminal, and the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands；

The receiving terminal 820 is additionally operable to receive the Nyquist domain configured information that the transmitting terminal is sent, the Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands, according to the Nyquist domain configured information, respective components of the target simulation signal in the first Nyquist domain are determined；Respective components of the receiving terminal according to the target simulation signal in the first Nyquist domain, analog-to-digital conversion process is carried out to the target simulation signal. End（For example, OLT), and, each unit in the transmitting terminal 810 is module and other above-mentioned operation and/or functions respectively in order to realize the corresponding flow of the method 100 in Fig. 1, in order to which cylinder is clean, in this receiving terminal that no longer receiving terminal 820 according to embodiments of the present invention may correspond in the method for the embodiment of the present invention（For example, ONU#l), also, each unit in the receiving terminal 820 be module and other above-mentioned operation and/or functions respectively in order to realize the corresponding flow of the method 300 in Fig. 5, in order to which cylinder is clean, will not be repeated here.

The system of transmission signal according to embodiments of the present invention, by configuring multiple DAC in transmitting terminal, the maximum output intensity of the analog signal after being handled through each DAC is set to be located at different Nyquist domains, and be that each receiving terminal distributes different frequency ranges in system bandwidth, transmitting terminal to receiving terminal when sending data, according to the Frequency Band Selection target DAC corresponding with the receiving terminal, so that target frequency bands belong to the Qwest domain at target DAC maximum output intensity, and to target DAC to needing the data for being sent to the receiving terminal to handle, to generate target simulation signal, and then it is sent to the receiving terminal, so as to which receiving terminal can be according to its corresponding frequency range, target simulation signal is recognized from system bandwidth, therefore, each DAC sample rate is without corresponding with system bandwidth, so as to reduce the requirement to DAC sample rates, and then reduce the cost of communication equipment and networking.

It should be understood that the terms " and/or ", only a kind of incidence relation for describing affiliated partner, represents there may be three kinds of relations, for example, A and/or B, can be represented：Individualism A, while there is A and B, these three situations of individualism B.In addition, character "/" herein, typically represent forward-backward correlation object be it is a kind of " or " relation.

It should be understood that, in various embodiments of the present invention, the size of the sequence number of above-mentioned each process is not meant to the priority of execution sequence, and the execution sequence of each process should be determined with its function and internal logic, and any limit is constituted without tackling the implementation process of the embodiment of the present invention.

Those of ordinary skill in the art are it is to be appreciated that the unit and algorithm steps of each example described with reference to the embodiments described herein, can be realized with the combination of electronic hardware or computer software and electronic hardware.These functions are performed with hardware or software mode actually, depending on the spy of technical scheme Fixed application and design constraint.Professional and technical personnel can realize described function to each specific application using distinct methods, but this realization is it is not considered that beyond the scope of this invention.

It is apparent to those skilled in the art that, the specific work process of the system of foregoing description, device and unit clean for the convenience and cylinder of description may be referred to the corresponding process in preceding method embodiment, will not be repeated here.

In several embodiments provided herein, it should be understood that disclosed systems, devices and methods, it can realize by another way.For example, device embodiment described above is only schematical, for example, the division of the unit, it is only a kind of division of logic function, there can be other dividing mode when actually realizing, such as multiple units or component can combine or be desirably integrated into another system, or some features can be ignored, or do not perform.Another, it, by some interfaces, the INDIRECT COUPLING or communication connection of device or unit, can be electrical, machinery or other forms that shown or discussed coupling or direct-coupling or communication connection each other, which can be,.

The unit illustrated as separating component can be or may not be physically separate, and the part shown as unit can be or may not be physical location, you can with positioned at a place, or can also be distributed on multiple NEs.Some or all of unit therein can be selected to realize the purpose of this embodiment scheme according to the actual needs.

In addition, each functional unit in each of the invention embodiment can be integrated in a processing unit or unit is individually physically present, can also two or more units it is integrated in a unit.

If the function is realized using in the form of SFU software functional unit and as independent production marketing or in use, can be stored in a computer read/write memory medium.Understood based on such, the part or the part of the technical scheme that technical scheme substantially contributes to prior art in other words can be embodied in the form of software product, the computer software product is stored in a storage medium, including some instructions are to cause a computer equipment（Can be personal computer, server, or network equipment etc.）Perform all or part of step of each embodiment methods described of the invention.And foregoing storage medium includes：USB flash disk, mobile hard disk, read-only storage（ROM, Read-Only Memory), random access memory（RAM, Random Access Memory), magnetic disc or CD etc. are various can be with the medium of store program codes.

It is described above; only embodiment of the invention, but protection scope of the present invention is not limited thereto, any one skilled in the art the invention discloses technical scope in; change or replacement can be readily occurred in, should be all included within the scope of the present invention.Therefore, protection of the invention Scope should be based on the protection scope of the described claims.

Claims

Claim

1, a kind of method for transmitting signal, it is characterized in that, performed by the transmitting terminal in communication system, the transmitting terminal has at least two digital analog converter DAC, feature Nyquist domain corresponding to each DAC is different, wherein, the feature Nyquist domain is the processing through corresponding DAC and the Nyquist domain at the maximum output intensity of analog signal that generates, the sample rate that at least two DAC is used is identical, the system bandwidth that the communication system is used is divided at least two frequency ranges, one frequency range belongs to the feature Nyquist domain corresponding to a DAC, methods described includes：

The transmitting terminal, which is obtained, to be needed to be sent to the target number signal of receiving terminal；

The transmitting terminal determines the target DAC corresponding with target frequency bands from least two DAC, wherein, the target frequency bands, which are the transmitting terminals, with the receiving terminal communicate the frequency range used, and the target frequency bands belong to the feature Nyquist domain corresponding to the target DAC；

The transmitting terminal is handled the target number signal by the target DAC, to generate target simulation signal；

The transmitting terminal sends the target simulation signal by the target frequency bands to the receiving terminal.2nd, according to the method described in claim 1, it is characterised in that when the feature Nyquist domain corresponding to the target DAC is not the first Nyquist domain, methods described also includes：

The transmitting terminal sends Nyquist domain configured information to the receiving terminal, and Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands.

3rd, method according to claim 1 or 2, it is characterised in that the transmitting terminal determines the target DAC corresponding with target frequency bands from least two DAC, including：

The transmitting terminal receives the registration request that the receiving terminal is sent；

The transmitting terminal is according to the registration request, from least two frequency range, is that the receiving terminal distributes the target frequency bands；

The transmitting terminal determines target DAC according to the target frequency bands from least two DAC;And

Methods described also includes：

The transmitting terminal sends the frequency range configured information for indicating the target frequency bands to the receiving terminal.

4th, method according to claim 1 or 2, it is characterised in that the transmitting terminal determines the target DAC corresponding with target frequency bands from least two DAC, including：

The transmitting terminal obtains mapping item, and the mapping item records the mapping relations between the receiving terminal and the target frequency bands； The transmitting terminal searches the mapping item, to determine the target frequency bands according to the receiving terminal；The transmitting terminal determines the target DAC according to the target frequency bands.

5th, method according to claim 1 or 2, it is characterised in that any frequency range that the receiving terminal can be at least two frequency range is communicated, and

The transmitting terminal determines the target corresponding with target frequency bands from least two DAC

DAC, including：

The transmitting terminal regard any DAC at least two DAC as the target DAC;The transmitting terminal determines the target frequency bands from the feature Nyquist domain corresponding to the target DAC；And

Methods described also includes：

The transmitting terminal sends the frequency range configured information for indicating the target frequency bands to the receiving terminal.

6th, method according to any one of claim 1 to 5, it is characterised in that in the transmitting terminal by the target frequency bands, before sending the target simulation signal to the receiving terminal, methods described also includes：

The transmitting terminal carries out the first filtering process, to retain the feature Nyquist domain being in corresponding to the target DAC or the part of the target frequency bands of the target simulation signal.

7th, method according to any one of claim 1 to 6, it is characterised in that in the transmitting terminal by the target frequency bands, before sending the target simulation signal to the receiving terminal, methods described also includes：

The transmitting terminal carries out the second filtering process, to retain the target simulation signal in the feature Nyquist domain corresponding to the target DAC or the target frequency bands.

8th, a kind of method for transmitting signal, it is characterised in that methods described includes：

The receiving terminal determines target frequency bands, and the target frequency bands are that the transmitting terminal with the receiving terminal communicate the frequency range used；

The receiving terminal obtains the target simulation signal that the transmitting terminal is sent according to the target frequency bands；The receiving terminal receives the Nyquist domain configured information that the transmitting terminal is sent, and Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands；

The receiving terminal determines respective components of the target simulation signal in the first Nyquist domain according to Nyquist domain configured information；

Respective components of the receiving terminal according to the target simulation signal in the first Nyquist domain, analog-to-digital conversion process is carried out to the target simulation signal. 9th, method according to claim 8, it is characterised in that the receiving terminal determines target frequency bands, including：

The receiving terminal receives the frequency range configured information for being used to indicate the target frequency bands that the transmitting terminal is sent, and the target frequency bands are that the transmitting terminal is the receiving terminal distribution from least two frequency range；

The receiving terminal determines the target frequency bands according to the frequency range configured information.

10th, method according to claim 9, it is characterised in that before the receiving terminal reception transmitting terminal transmission is for indicating the frequency range configured information of the target frequency bands, methods described also includes：

The receiving terminal sends registration request to the transmitting terminal, in order to which the transmitting terminal according to the registration request is that the receiving terminal distributes the target frequency bands from least two frequency range, and sends the frequency range configured information.

11st, method according to claim 8, it is characterised in that the receiving terminal determines target frequency bands, including：

The receiving terminal obtains mapping item, and the mapping item record has the mapping relations between the receiving terminal and the target frequency bands；

The receiving terminal searches the mapping item, to determine the target frequency bands.

12nd, a kind of device for transmitting signal, it is characterised in that described device includes：

At least two digital analog converter DAC, feature Nyquist domain corresponding to each DAC is different, wherein, the feature Nyquist domain is the processing through corresponding DAC and the Nyquist domain at the maximum output intensity of analog signal that generates, the sample rate that at least two DAC is used is identical, the system bandwidth that the communication system is used is divided at least two frequency ranges, and a frequency range belongs to the feature Nyquist domain corresponding to a DAC；

Acquiring unit, needs to be sent to the target number signal of receiving terminal for obtaining；

Determining unit, for determining the target corresponding with target frequency bands from least two DAC

DAC, wherein, the target frequency bands, which are described devices, with the receiving terminal communicate the frequency range used, and the target frequency bands belong to the feature Nyquist domain corresponding to the target DAC；

Generation unit, for being handled by the target DAC the target number signal, to generate target simulation signal；

Transmit-Receive Unit, for by the target frequency bands, the target simulation signal to be sent to the receiving terminal. 13rd, device according to claim 12, it is characterized in that, when the feature Nyquist domain corresponding to the target DAC is not the first Nyquist domain, the Transmit-Receive Unit is additionally operable to send Nyquist domain configured information to the receiving terminal, and Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands.

14th, the device according to claim 12 or 13, it is characterised in that the Transmit-Receive Unit is additionally operable to receive the registration request that the receiving terminal is sent；

The determining unit is additionally operable to according to the registration request, from least two frequency range, is that the receiving terminal distributes the target frequency bands, and according to the target frequency bands, target DAC is determined from least two DAC;

The Transmit-Receive Unit is additionally operable to send the frequency range configured information for indicating the target frequency bands to the receiving terminal.

15th, the device according to claim 12 or 13, it is characterised in that the acquiring unit is additionally operable to obtain mapping item, and the mapping item record has the mapping relations between each receiving terminal and each frequency range；

The determining unit is specifically for according to the receiving terminal, searching the mapping item, to determine the target frequency bands, and according to the target frequency bands, determining the target DAC.

16th, the device according to claim 12 or 13, characterized in that, the receiving terminal can be at least two frequency range any frequency range communicated, and mark DAC, and from the feature Nyquist domain corresponding to the target DAC, determine the target frequency bands；

The Transmit-Receive Unit is additionally operable to send the frequency range configured information for indicating the target frequency bands to the receiving terminal.

17th, the device according to any one of claim 12 to 16, it is characterized in that, the generation unit is additionally operable to carry out the first filtering process, only to retain the part in the feature Nyquist domain corresponding to the target frequency bands or the target DAC of the target simulation signal.

18th, the device according to any one of claim 12 to 17, it is characterized in that, the generation unit is additionally operable to carry out the second filtering process, only to retain the target simulation signal in the feature Nyquist domain corresponding to the target frequency bands or the target DAC.

19th, a kind of device for transmitting signal, it is characterised in that described device includes：

Determining unit, for determining target frequency bands, the target frequency bands are that transmitting terminal is carried out with described device Communicate the frequency range used；

Transmit-Receive Unit, for according to the target frequency bands, the target simulation signal that the transmitting terminal is sent is obtained, and receives the Nyquist domain configured information that the transmitting terminal is sent, Nyquist domain configured information is used to indicate the Nyquist domain at the target frequency bands；

Processing unit, for according to Nyquist domain configured information, determine respective components of the target simulation signal in the first Nyquist domain, and the respective components according to the target simulation signal in the first Nyquist domain, analog-to-digital conversion process is carried out to the target simulation signal, to obtain the target number signal.

20th, method according to claim 19, it is characterized in that, the Transmit-Receive Unit is additionally operable to receive the frequency range configured information for being used to indicate the target frequency bands that the transmitting terminal is sent, the target frequency determining unit is specifically for according to the frequency range configured information, determining the target frequency bands.

21st, method according to claim 20, it is characterized in that, the Transmit-Receive Unit is additionally operable to send registration request to the transmitting terminal, in order to which the transmitting terminal according to the registration request is that the receiving terminal distributes the target frequency bands from least two frequency range, and send the frequency range configured information.

22nd, method according to claim 19, it is characterised in that the determining unit is additionally operable to obtain mapping item, and the mapping item record has the mapping relations between the receiving terminal and the target frequency bands；

For searching the mapping item, to determine the target frequency bands.

23rd, a kind of system for transmitting signal, it is characterised in that the system includes：

Device according to any one of claim 12 to 18；Or

Device according to any one of claim 12 to 18 and the device according to any one of claim 19 to 22.