CN1305305A - Transmission method of grading multidimensional frequency in telecommunication network - Google Patents
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- CN1305305A CN1305305A CN01108015.9A CN01108015A CN1305305A CN 1305305 A CN1305305 A CN 1305305A CN 01108015 A CN01108015 A CN 01108015A CN 1305305 A CN1305305 A CN 1305305A
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Abstract
A hierarchical multi-frequency transmission method over telecommunication network features that multiple signal frequencies to be transmitted are hierarchieally modulated to pointed frequency axle, pointed frequency layers and pointed frequency by the hierarchical modulation method. The modulated carrier is bidirectionally transmitted over telecommunication network directly or after digitalized. At receiving end, "stripper", band-pass filter, detector and filter are used to obtain original data (information).
Description
The present invention is a kind of generating multi-dimension hierarchical frequency approach of utilizing, through the level modulation that repeats a plurality of data to be modulated (signal frequency) are modulated to respectively on specified frequency axle, frequency level and the assigned frequency, through linear superposition, constitute the generating multi-dimension hierarchical FM wave, copper twisted pair transmitted in both directions through telecommunication department, pass through linear branch again, frequency-selecting amplification, detection filter, the new information transferring method that raw information is restored.
A host of facts show that network speed is two big obstacles of China Internet development with the charge height slowly.A lot of users are seeking the fast and high network access of the ratio of performance to price of a kind of networking speed.User access networks (from local call office to the part the user) are the important component parts of telecommunications network, are the windows of telecommunications network, also are " last mile " (the last mile) of information superhighway.But user access networks become the bottleneck of Modern Telecommunication net still based on copper cash.The fast development of Internet technology makes multi-medium datas such as the video/audio that transmits on the network and high definition image more and more, these information are being engulfed limited channel width resource with fearful speed, and therefore traditional Access Network must develop to the high-band broadening.As new broadband access means, Optical Access Network is a state-of-the-art access network technology in the telecommunications network.Yet telecommunications company expends the huge twisted-pair feeder copper cable net of huge fund laying can not all be replaced by optical cable, thereby the Digital Subscriber Line of on existing copper twisted pair cable, developing (xDSL) access technology, become the main access technology that telecommunications company captures Access Network market.
ADSL is a kind of Internet solution of high speed, and it uses ordinary telephone line with the most use in the world as transmission medium.Traditional telephone wire transmission, it has only used the low-frequency range of 0～4KHz, and the phone copper cash has the bandwidth near 2MHz in theory, ADSL just has been to use the later high frequency band of 26KHz that high speed like this just is provided.Yet even if near the bandwidth of 2MHz, it is very limited that its frequency resource remains.
The purpose of this invention is to provide a kind of transmittability that improves communication network, increase the width of base band, improve the transmission method of the middle-level multi-dimension frequency of communication network of transmission speed.
The solution of the present invention is to adopt the method for level modulation, through the level modulation that repeats a plurality of data to be modulated (signal frequency) is modulated to respectively on specified frequency axle, frequency level and the assigned frequency.This specified frequency is exactly a carrier wave, the carrier wave of the multi-level modulation of such process has been not the notion of a frequency just, but the notion of generating multi-dimension hierarchical frequency, promptly a carrier wave can be to there being the frequency of a lot of generating multi-dimension hierarchicals, under the situation that he is certain at channel and bandwidth is certain, through the frequency utilization of multi-level and multidimensional, the information transmitted amount will be very huge.With transmitting on the modulated carrier wave communication network, at receiving terminal, by the linear branch device, frequency selective amplifier and detection filter come out each reduction of data.
Its concrete scheme adopts the method for level modulation with the successively modulation of a plurality of signal frequencies waiting for transmission through repeating, be modulated to respectively on specified frequency axle, specified frequency level and the specified frequency, again modulated carrier wave directly or after the digitlization is carried out transmitted in both directions by telecommunications network, at receiving terminal, utilize by " stripper ", adopt linear the reception, band pass filter (as frequency selective amplifier), successively the generating multi-dimension hierarchical frequency is peeled off out, after detection filter restores former data (information).Adopt the level modulator approach will many frequencies to be modulated to be modulated to formation (f on the modulation level of appointment and the specified frequency respectively
1→ f
2→ f
3→ ... f
n), be about to several frequency f to be modulated
1(1) to f
1(k
1) with modulator they are modulated on any frequency of corresponding appointment respectively one by one, form the f of ground floor modulation
2(1) to f
2(k
2), the frequency f after will modulating respectively again
2(1) to f
2(k
2) through modulator they are modulated on any frequency of corresponding appointment respectively once more one by one, form the f of second layer modulation
3(1) to f
3(k
3), modulate the f that forms the modulation of n layer through n-1 time level by that analogy
n(1) to f
n(k
n).Frequency f after the modulation
n(j
n) more than or equal to modulated frequency f before the modulation
N-1(j
N-1) 3 times be f
n(j
n) 〉=3f
N-1(j
N-1).Frequency wherein to be modulated has " k " individual, i.e. f
1(1) to f
1(k), j frequency in 1 to k frequency is f
1(j).The frequency of primary frequency n layer modulation is f relatively
n(1) to f
n(k), j frequency is at the modulation result f of n layer
n(j).The modulator that adopts is amplitude-modulated wave modulator or frequency-modulated wave modulator or phase modulation modulator or the double modulator of transferring of Frequency and Amplitude.Stripper is adopted in the reception of system, promptly adopts linear reception, bandpass filtering, detection filter, delamination.The invention has the advantages that:
This method is used on a given frequency generating multi-dimension hierarchical frequency simultaneously.
This method is different from the notion of frequency division multiplexing in general sense fully, use this method can be under the prerequisite that keeps certain bandwidth and certain transmission rate, increase substantially the transmission of Information ability, particularly in solving single channel, increase substantially under the prerequisite of message transmission capability, can make a given transmission channel transmit a lot of call gates or data, making only needs limited passage just can satisfy the demand of people to broadband, network speed.Adopt modulation (demodulation), multiplexing (demultiplexing) technology, under present circumstances, device is more cheap, and performance is also reliable, and electrical filter can be designed as efficiently, the multiple spot filter of near ideal.Whole method for designing, circuit is simple.
Because the present invention has greatly increased frequency resource, under the very rich situation of frequency resource, we just can revise the allocative decision of existing frequency, enlarge the bandwidth that frequency range and channel arrive, thereby improve the speed of message transmission, from the service efficiency of higher level raising communication network.
This method need not to revise any existing convention and network configuration, just respectively adds under the situation of a modulator-demodulator at the line outlet of telecommunications company and user's telephone line inlet, can erect a high-speed channel between MCI and end user.Most critical be that it can use 600,000,000 the copper twisted-pair feeder of surpassing that spreads all over the world, for the company that telecommunications service are provided, they need not need to drop into astronomical fund for changing circuit again, and he can be for the user provides more online service, and can bring good economic benefits.For the user that phone has been installed, the multimedia service on the Internet is being not the thing in the imagination, can go up the various video and audio programs of online program request, participates in video conference, enjoy long-distance education at home.Implementing this technology, can reduce the intensity of communications field infrastructure construction and the input of fund greatly, form the information transmission system of brand-new communication network, will be a great breakthrough to the development of quickening IT application process and propulsion information industry.
Fig. 1 is the transmission of traditional telephone wire, based on the transmission of ADSL technology telephone wire with based on the principle schematic of the telephone wire transmission of generating multi-dimension hierarchical technology.
Fig. 1 a is the utilization of traditional phone line frequency resource.
Fig. 1 b is the utilization of ADSL system to frequency resource.
Fig. 1 c, 1d are the utilization of generating multi-dimension hierarchical frequency resource.
Fig. 2 is the structure of generating multi-dimension hierarchical frequency and the schematic diagram of information reverting.
Fig. 3 is traditional telephone users circuit network and the modulator of generating multi-dimension hierarchical frequency structure and the allocation position of stripper.
Fig. 4 is the carrier wave f on frequency axis of k in the m bar frequency axis
a, f
bF
nSimultaneously to data
1, data
2... data
nHandle and 2 of the schematic diagram of analogue transmission.
Fig. 5 is the carrier wave f on frequency axis of k in the m bar frequency axis
a, f
bF
nSimultaneously to data
1, data
2... data
n3 of the schematic diagram of handling and transmitting.
Fig. 6 is the carrier wave f on frequency axis of k in the m bar frequency axis
a, f
bF
nSimultaneously to data
1, data
2... data
nHandle schematic diagram with Digital Transmission
The present invention will be further described below in conjunction with drawings and Examples.
As shown in Figure 1a, based on the message transmission of traditional telephone wire, it has only used the low-frequency range of 0～4KHz, also has the bandwidth of 4KHz-2G Hz not use.Fig. 1 b represents to have utilized the ADSL technology, has used the later high frequency band of 26KHz, and 26KHz～1.1MHz frequency band is divided into 25 up subchannels and 249 descending subchannels with the width of 4K.Fig. 1 c, Fig. 1 d represent to utilize the generating multi-dimension hierarchical frequency technique to form multi-level vehicle and three-dimensional traffic, thus the flow of the information of increasing.
Because the width limited (0MHz-2GHz) of highway, the passage that can divide out on this limited having a lot of social connections is just very limited, and the passage of division is many more, and single width of channel is just narrow more, and transmission speed is low more.Therefore, under the existing situation or under the following situation that the amount of information demand is increased, not to feel to feel that exactly the speed of message transmission does not catch up with because the business that channel resource causes inadequately can not meet the demands.
We adopt the generating multi-dimension hierarchical frequency approach, promptly adopt the level modulator approach that many frequencies to be modulated are modulated to respectively and form (f on the modulation level of appointment and the specified frequency
1→ f
2→ f
3→ ... f
n), be about to several frequency f to be modulated
1(1) to f
1(k
1) with modulator they are modulated on any frequency of corresponding appointment respectively one by one, form the f of ground floor modulation
2(1) to f
2(k
2), the frequency f after will modulating respectively again
2(1) to f
2(k
2) through modulator they are modulated on any frequency of corresponding appointment respectively once more one by one, form the f of second layer modulation
3(1) to f
3(k
3), modulate the f that forms the modulation of n layer through n-1 time level by that analogy
n(1) to f
n(k
n).Frequency f after the modulation
n(j
n) more than or equal to modulated frequency f before the modulation
N-1(j
N-1) 3 times be f
n(j
n) 〉=3f
N-1(j
N-1).Frequency wherein to be modulated has " k " individual, i.e. f
1(1) to f
1(k), j frequency in 1 to k frequency is f
1(j).The frequency of primary frequency n layer modulation is f relatively
n(1) to f
n(k), j frequency is at the modulation result f of n layer
n(j) (Fig. 2).
At present, the modulator of ADSL use has QAM, CAP and DMT.DMT is exactly multifrequency frequency multiplexing technique in essence, his 0-1.104MHZ band segmentation is 256 orthogonal sub-channels (each subchannel takies the 4KHz bandwidth) by the frequency indication, input signal is through Bit Allocation in Discrete and buffer memory, to import data and be divided into bit block, carry out the sharp leaf inverse transformation of 512 point discrete Fouriers again and convert the signal into time domain behind the TCM coding, at this moment bit block will convert 256 QAM characters to.Subsequently each bit block is added Cyclic Prefix (being used to eliminate intersymbol interference), signal is served channel through data modular transformation and transmitting filter.Then receive decoding at receiving terminal by opposite order.
According to the generating multi-dimension hierarchical frequency technique, on the 26KHZ-1.104MHz frequency band, take the 4KHz bandwidth according to each subchannel and construct, the channel that can arrange on the one dimension frequency axis is 270, on two and three dimensions, then the channel that can arrange is respectively 1.12 * 10
4With 6.99 * 10
4Take the 30KHz bandwidth according to each subchannel and construct, the channel that can arrange on the one dimension frequency axis is 35, and on two and three dimensions, then the channel that can arrange is respectively 224 and 284.
The contrast of the number of users that table 1 is supported on one dimension, two and three dimensions frequency axis
| Dimension Δ f | ????4 | ????10 | ????20 | ????30 |
| One dimension | ????270 | ????107 | ????53 | ????35 |
| Two dimension | ????1.12×10 4 | ????1.84×10 3 | ????4.82×10 2 | ????2.24×10 2 |
| Three-dimensional | ????6.99×10 4 | ????5.12×10 3 | ????7.89×10 2 | ????2.84×10 2 |
Fig. 3 has indicated at traditional telephone users circuit network and the modulator of generating multi-dimension hierarchical frequency structure and the allocation position of stripper.
Fig. 4 is the signal 1 of the framework of our scheme.
(1) oscillator A and isolator 1, isolator 2 ... isolator n has formed a carrier wave.
(2) oscillator 1 has been formed modulator 1 with vision signal or voice signal, the output of modulator 1 and oscillator A have formed modulator 2 again, oscillator 2 has been formed modulator 3 with vision signal or voice signal, and the output of modulator 3 and oscillator A have formed modulator 4 again ...
(3) with modulator 2, modulator 4 ..., the output frequency of modulator n carries out linear superposition.
The condition that need to satisfy be oscillator A frequency of oscillation should more than or equal to 3 times modulator 1, modulator 2 ..., the highest frequency of exporting among the modulator n.
(4) with several carrier frequency process linear superposition,, enter and the corresponding linear branch device of linear superposition, the voice signal of linear superposition is handled along separate routes through the communication network transmission.
(5) frequency selective amplifier 1, frequency selective amplifier 3 ..., frequency selective amplifier m, carry out the frequency-selecting first time, frequency selective amplifier 2, frequency selective amplifier 4 ... frequency selective amplifier n carries out the frequency-selecting second time, and the purpose that twice frequency-selecting amplified is exactly to increase the effect that frequency-selecting is amplified.
(6) restore vision signal or voice signal through detection filter.
Fig. 5 is the signal 2 of the framework of our scheme, represented n level on the some frequencies on a certain frequency axis in m bar frequency axis the frequency resource level multiplexing method.We can think to utilize to visualization a carrier wave to transmit data simultaneously like this
1, data
2..., data
n, the carrier wave that also can utilize other frequencies simultaneously transmission video signal or voice signal 1, vision signal or voice signal 2 ... vision signal or voice signal n.
This invention proposes the data compression method based on the generating multi-dimension hierarchical frequency simultaneously.
As shown in Figure 6, for data
1, data
2..., data
nBe digital information, they can handle through overcompression.Illustrated empty frame first increases the generating multi-dimension hierarchical frequency and forms part, with carrier wave f
a, f
bF
kAnalog-to-digital conversion is promptly passed through in digitlization, and this modulus/digital-to-analogue conversion mode has multiple, the technology comparative maturity.To send through the digital information compression that analog-to-digital conversion obtains again, through the telephone wire transmission.At the second portion of empty frame, through digital to analog conversion, peel off layer by layer, carry out information reverting.
The key point of receiving system of the present invention is at receiving terminal utilization " stripper ", the generating multi-dimension hierarchical FM wave is adopted linear the reception, band pass filter (as frequency selective amplifier) is successively peeled off out with the generating multi-dimension hierarchical frequency, after detection filter takes out data (information).
Its specific embodiment is as follows:
In order to prove above-mentioned design, we have carried out the carrier wave f on frequency axis of k in the m bar frequency axis
aSimultaneously to data
1, data
2..., data
nHandle and transmit prototype design.
The frequency of oscillation that oscillator produces is 1.4MHz, and the frequency of oscillation that oscillator 1, oscillator 2, oscillator 3, oscillator 4 produce is respectively 100KHz, 150KHz, 200KHz, 250KHz.Data
1, data
2, data
3, data
4For can also being audio signal for vision signal.
Data
1Being modulated at the last modulating wave that forms of 100KHz is modulated on the 1.4MHz again; Data
2Being modulated at the last modulating wave that forms of 150KHz is modulated on the 1.4MHz again; Data
3Being modulated at the last modulating wave that forms of 200KHz is modulated on the 1.4MHz again; Data
4Being modulated at the last modulating wave that forms of 250KHz is modulated on the 1.4MHz again; 1.4MHz modulating wave all satisfies peaked 3 times in 100KHz, 150KHz, 200KHz, the 250KHz modulating wave.
Again with data
1Be modulated at the last modulating wave that forms of 100KHz and be modulated at modulating wave and the data that 1.4MHz goes up formation again
2Be modulated at the last modulating wave that forms of 150KHz and be modulated at the modulating wave that 1.4MHz goes up formation, data again
3Be modulated at the last modulating wave that forms of 200KHz and be modulated at the modulating wave that 1.4MHz goes up formation again, and data
4The modulating wave that is modulated at the last formation of 250KHz is modulated at the last modulating wave that forms of 1.4MHz again and carries out linear superposition.
1.4MHz carrier wave (1) is direct, in communication network, carry out transmitted in both directions after (2) digitlization.
Frequency selective amplifier 1 and frequency selective amplifier carried out the frequency that 100KHz is selected in twice frequency-selecting in 2 minutes; Frequency selective amplifier 3 and frequency selective amplifier carried out the frequency that 150KHz is selected in twice frequency-selecting in 4 minutes, and frequency selective amplifier 5 and frequency selective amplifier carried out the frequency that 200KHz is selected in twice frequency-selecting in 6 minutes; Frequency selective amplifier 7 and frequency selective amplifier carried out the frequency that 250KHz is selected in twice frequency-selecting in 8 minutes.(6) detection filter of the frequency of the frequency of the frequency of the frequency of process 100KHz, 150KHz, 200KHz and 250KHz restores data respectively
1, data
2, data
3And data
4
Claims (4)
1. the transmission method of the middle-level multi-dimension frequency of communication network, it is characterized in that adopting the method for level modulation with of the successively modulation of a plurality of signal frequencies waiting for transmission through repeating, be modulated to respectively on specified frequency axle, specified frequency level and the specified frequency, again modulated carrier wave directly or after the digitlization is carried out transmitted in both directions by telecommunications network, at receiving terminal, utilize by " stripper ", adopt linear the reception, band pass filter, successively the generating multi-dimension hierarchical frequency is peeled off out, after detection filter restores former data.
2. the transmission method of the middle-level multi-dimension frequency of communication network according to claim 1, the method that it is characterized in that level modulation promptly adopts the level modulator approach will many frequencies to be modulated to be modulated to formation (f on the modulation level of appointment and the specified frequency respectively
1→ f
2→ f
3→ ... f
n), be about to several frequency f to be modulated
1(1) to f
1(k
1) with modulator they are modulated on any frequency of corresponding appointment respectively one by one, form the F of ground floor modulation
2(1) to f
2(k
2), the frequency f after will modulating respectively again
2(1) to f
2(k
2) through modulator they are modulated on any frequency of corresponding appointment respectively once more one by one, form the f of second layer modulation
3(1) to f
3(k
3), modulate the f that forms the modulation of n layer through n-1 time level by that analogy
n(1) to f
n(k
n), the frequency f after the modulation
n(j
n) more than or equal to modulated frequency f before the modulation
N-1(j
N-1) 3 times be f
n(j
n) 〉=3f
N-1(j
N-1).
3. the transmission method of the middle-level multi-dimension frequency of communication network according to claim 1 and 2 is characterized in that the modulator that adopts is amplitude-modulated wave modulator or frequency-modulated wave modulator or phase modulation modulator or the double modulator of transferring of Frequency and Amplitude.
4. the middle-level multi-dimension frequency transmission method of communication network according to claim 1 is characterized in that adopting stripper, promptly adopts linear reception, bandpass filtering, detection filter, delamination.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN01108015.9A CN1305305A (en) | 2001-01-05 | 2001-01-05 | Transmission method of grading multidimensional frequency in telecommunication network |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN01108015.9A CN1305305A (en) | 2001-01-05 | 2001-01-05 | Transmission method of grading multidimensional frequency in telecommunication network |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1305305A true CN1305305A (en) | 2001-07-25 |
Family
ID=4656905
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN01108015.9A Pending CN1305305A (en) | 2001-01-05 | 2001-01-05 | Transmission method of grading multidimensional frequency in telecommunication network |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1305305A (en) |
-
2001
- 2001-01-05 CN CN01108015.9A patent/CN1305305A/en active Pending
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