CN111132334A - Space division multiple access communication method based on harmonic modulation technology - Google Patents
Space division multiple access communication method based on harmonic modulation technology Download PDFInfo
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W72/00—Local resource management
- H04W72/04—Wireless resource allocation
- H04W72/044—Wireless resource allocation based on the type of the allocated resource
- H04W72/046—Wireless resource allocation based on the type of the allocated resource the resource being in the space domain, e.g. beams
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
- H04L27/28—Systems using multi-frequency codes with simultaneous transmission of different frequencies each representing one code element
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/0408—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas using two or more beams, i.e. beam diversity
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
- H04B7/0686—Hybrid systems, i.e. switching and simultaneous transmission
- H04B7/0695—Hybrid systems, i.e. switching and simultaneous transmission using beam selection
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Abstract
The invention discloses a space division multiple access communication method based on a harmonic modulation technology, which adopts an adaptive array antenna to realize space division, forms different wave beams in different user directions and provides information access for users in different areas by using the different antenna wave beams; and the same carrier frequency or different carrier frequencies used to serve different areas covered by the antenna beam all use fundamental frequencies and harmonics for information transmission. The information transmission process comprises the following steps: firstly, different information is modulated, then the different information is loaded on different harmonic components or component combinations respectively, and finally the fundamental frequency and the harmonic information received by a receiving end are demodulated. The invention fully utilizes the capability of harmonic wave transmission information, greatly improves the utilization rate of frequency spectrum, and simultaneously greatly excavates and excites the potential of the existing frequency spectrum resource, so that the existing space division multiple access communication method can be greatly wonderful in the coming 5G era.
Description
Technical Field
The invention relates to the technical field of communication, in particular to a space division multiple access communication method based on a harmonic modulation technology.
Background
The radio spectrum (radiospect) generally refers to a generic term for radio frequencies that emit radio waves in the frequency range of 9KHz to 3000 GHz. All radio services are radio frequency independent, as if the vehicle had to travel on the road.
The nature of the radio spectrum determines its underlying resources for the telecommunications industry. First, the radio spectrum is limited. Radio services cannot infinitely use radio frequencies of a higher frequency band due to propagation characteristics of radio waves at a higher frequency, and at present, mankind cannot develop and utilize frequencies above 3000GHz, and although frequency reuse can be performed according to four ways of time, space, frequency and coding by using a radio spectrum, the frequency use is limited in a certain region, a certain time and a certain condition with respect to a certain frequency band and frequency; second, exclusivity of the radio spectrum. Radio spectrum resources have a common property with other resources, namely exclusivity, that once used, other devices are no longer available in a certain time, region and frequency domain. These two characteristics determine that once a certain frequency band is assigned to a certain service, it means that other services and even devices cannot utilize the frequency band.
With the progress of radio technology and the development of economic society, a great deal of various applications and various radio devices emerge, and the demand of various industries on radio frequency is increasing. The current trend is that the requirements of road and railway transportation, air transportation and marine transportation on related communication and navigation technologies, particularly emerging GPS positioning and satellite communication, are further increased along with the further development of the economy of China. Communications and navigation services associated with these areas will then occupy a portion of the radio spectrum. Therefore, frequency bands reserved for the telecommunication industry in the future, especially for the 5G network in the future, are becoming increasingly scarce resources.
As shown in fig. 1, the conventional sdma communication method distinguishes different users by spatial division, and achieves spatial orthogonal isolation by dividing a cell into different subspaces using wireless directional beams. Conventional spatial division multiple access communication methods provide access to users in different areas using different antenna beams. The same frequency (in a CDMA system) or different frequencies (in an FDMA system) are used to serve these different areas covered by the antenna beams. In both the CDMA and FDMA systems described above, the fundamental frequency is used for information transmission, while the ability to transmit information in harmonic form is ignored. This results in a waste of spectrum resources. Especially, under the circumstance that the spectrum resources are so tight at present (especially in the coming 5G era), the spectrum resources cannot be fully utilized, and the traditional space division multiple access communication method is inevitably eliminated because the traditional space division multiple access communication method cannot meet the actual requirements at present. Therefore, how to improve the spectrum utilization rate of the space division multiple access communication method is a problem which needs to be solved urgently at present.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a space division multiple access communication method based on a harmonic modulation technology, which has high frequency spectrum utilization rate.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
a space division multiple access communication method based on harmonic modulation technology adopts a self-adaptive array antenna to realize space division, forms different wave beams in different user directions, and provides information access for users in different areas by using different antenna wave beams; and the same carrier frequency or different carrier frequencies used to serve different areas covered by the antenna beam all use fundamental frequencies and harmonics for information transmission.
Further, the information transmission process is as follows: firstly, different information is modulated, then the different information is loaded on different harmonic components, and finally the fundamental frequency and the harmonic information received by a receiving end are demodulated.
Further, before the information transmission, a fixed harmonic pattern is stored in advance, and all the different signals are calculated using a given harmonic component, thereby demodulating a desired signal from other signals.
Further, based on the pre-stored fixed harmonic patterns, all two different signals are calculated using the given harmonic components, so that the specific process of demodulating the desired signal from the other signals is as follows:
all harmonic modes are assumed to be known:
Vout＝a0f0+a2f2+a3f3+a4f4+a5f5+…+anfm(1)
wherein, anRepresents the coefficient of n-th harmonic, n is 0,2,3,4, …; f. of0Represents the fundamental frequency; f. ofmRepresents the m-th harmonic component, m is 2,3,4, …;
at this time, the first signal and the second signal are respectively and completely loaded on the even harmonic and the odd harmonic for transmission, and the following results can be obtained:
finally, the mixed signal of the signal one and the signal two received at the signal receiving end is:
Vout＝a0 vf0+a0 pf0+a2 pf2+a3 vf3+a4 pf4+a5 vf5+a6 pf6+a7 vf7+a8 pf8+a9 vf9+… (4)
from (1) and (4):
a0 vf0+a0 pf0＝a0f0(5)
a2 pf2＝a2f2；a4 pf4＝a4f4；a6 pf6＝a6f6；a8 pf8＝a8f8；… (6)
a3 vf3＝a3f3；a5 vf5＝a5f5；a7 vf7＝a7f7；a9 vf9＝a9f9；… (7)
since the fundamental frequencies used for transmitting the first signal and the second signal are the same and only the harmonic components are different, it can be known from (5):
therefore, the receiving end can demodulate all of the signal one and the signal two according to the equations (6) to (8).
Further, when different information is modulated and then respectively loaded on different harmonic components to transmit signals, different harmonic component combinations can be selected according to requirements to transmit signals.
Compared with the prior art, the principle and the advantages of the scheme are as follows:
according to the scheme, information is loaded on different harmonic components or component combinations respectively through a harmonic modulation technology, and the information is transmitted by utilizing harmonic waves, so that the capability of transmitting information by utilizing the harmonic waves is fully utilized, the utilization rate of frequency spectrum is greatly improved, and the potential of the existing frequency spectrum resources is also greatly excavated and excited, so that the existing space division multiple access communication method can greatly magnify the diversity of the coming 5G era.
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In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the services required for the embodiments or the technical solutions in the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is a schematic diagram of the operation principle of a conventional space division multiple access communication method;
fig. 2 is a schematic diagram of the operation of the space division multiple access communication method based on the harmonic modulation technique;
FIG. 3 is a circuit diagram of a harmonic modulation circuit;
Detailed Description
The invention will be further illustrated with reference to specific examples:
to think of natural communication between human beings, the frequency bandwidth of a 70 hundred million people is only 20Hz-20 kHz! Noise, animal, wind, tree, etc. all sounds in nature occupy only this bandwidth. But humans can recognize them without difficulty. For example, in a concert, there are many different instruments playing the same melody, but one can identify each instrument. The reason is that each instrument plays the same pitch (fundamental frequency is the same), but the harmonic patterns are different. This means that in practice harmonics can also carry information, not just the fundamental frequencies that are currently in common use.
Based on this, as shown in fig. 2, this embodiment describes a space division multiple access communication method based on a harmonic modulation technique, which specifically includes the following steps:
the space division is realized by adopting the self-adaptive array antenna, different beams are formed in different user directions, and information access is provided for users in different areas by using the different antenna beams; and the same carrier frequency or different carrier frequencies used to serve different areas covered by the antenna beam all use fundamental frequencies and harmonics for information transmission.
Specifically, the information transmission process is as follows:
firstly, different information is modulated, then the different information is loaded on different harmonic components, and finally the fundamental frequency and the harmonic information received by a receiving end are demodulated.
The harmonic modulation circuit is shown in fig. 3, and the output of the harmonic modulation circuit is the sum of all input voltages. For inputs with the same fundamental frequency but different harmonic components, the outputs are different. Before information transmission, a fixed harmonic pattern is stored in advance, and all different signals can be calculated by using a given harmonic component, so that a desired signal can be demodulated from other signals.
For better understanding, it is not assumed that all harmonic modes are known (the signals required for the calculation are two):
Vout＝a0f0+a2f2+a3f3+a4f4+a5f5+…+anfm(1)
wherein, anRepresents the coefficient of n-th harmonic, n is 0,2,3,4, …; f. of0Represents the fundamental frequency; f. ofmRepresents the m-th harmonic component, m is 2,3,4, …;
at this time, the first signal and the second signal are respectively and completely loaded on the even harmonic and the odd harmonic for transmission, and the following results can be obtained:
finally, the mixed signal of the signal one and the signal two received at the signal receiving end is:
Vout＝a0 vf0+a0 pf0+a2 pf2+a3 vf3+a4 pf4+a5 vf5+a6 pf6+a7 vf7+a8 pf8+a9 vf9+… (4)
from (1) and (4):
a0 vf0+a0 pf0＝a0f0(5)
a2 pf2＝a2f2；a4 pf4＝a4f4；a6 pf6＝a6f6；a8 pf8＝a8f8；… (6)
a3 vf3＝a3f3；a5 vf5＝a5f5；a7 vf7＝a7f7；a9 vf9＝a9f9；… (7)
since the fundamental frequencies used for transmitting the first signal and the second signal are the same and only the harmonic components are different, it can be known from (5):
therefore, the receiving end can demodulate all of the signal one and the signal two according to the equations (6) to (8).
In addition to the above, the first and second signals may be transmitted using different combinations, such as loading the first signal with second and third harmonic components and loading the second signal with a fourth harmonic component. In practical use, different harmonic component combinations can be selected according to requirements to transmit signals.
According to the embodiment, information is loaded on different harmonic components or component combinations respectively through a harmonic modulation technology, and the information is transmitted by utilizing harmonic waves, so that the capability of transmitting information by utilizing the harmonic waves is fully utilized, the utilization rate of frequency spectrum is greatly improved, and the potential of the existing frequency spectrum resources is also greatly excavated and excited, so that the existing space division multiple access communication method can greatly magnify the diversity of the coming 5G era.
The above-mentioned embodiments are merely preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, so that variations based on the shape and principle of the present invention should be covered within the scope of the present invention.
Claims (5)
1. A space division multiple access communication method based on harmonic modulation technology adopts a self-adaptive array antenna to realize space division, forms different wave beams in different user directions, and provides information access for users in different areas by using different antenna wave beams; the method is characterized in that the same carrier frequency or different carrier frequencies used for serving different areas covered by the antenna beams are used for information transmission by using fundamental frequency and harmonic waves.
2. The spatial division multiple access communication method based on the harmonic modulation technique as claimed in claim 1, wherein the information transmission process is: firstly, different information is modulated, then the different information is loaded on different harmonic components, and finally the fundamental frequency and the harmonic information received by a receiving end are demodulated.
3. A spatial division multiple access communication method based on a harmonic modulation technique according to claim 2, wherein a fixed harmonic pattern is stored in advance before the information transmission, and all different signals are calculated using a given harmonic component, thereby demodulating a desired signal from other signals.
4. A spatial division multiple access communication method based on a harmonic modulation technique according to claim 3, wherein based on the pre-stored fixed harmonic patterns, all two different signals are calculated using a given harmonic component, so that the specific procedure for demodulating the desired signal from the other signals is as follows:
all harmonic modes are assumed to be known:
Vout＝a0f0+a2f2+a3f3+a4f4+a5f5+…+anfm(1)
wherein, anRepresents the coefficient of n-th harmonic, n is 0,2,3,4, …; f. of0Represents the fundamental frequency; f. ofmRepresents the m-th harmonic component, m is 2,3,4, …;
at this time, the first signal and the second signal are respectively and completely loaded on the even harmonic and the odd harmonic for transmission, and the following results can be obtained:
finally, the mixed signal of the signal one and the signal two received at the signal receiving end is:
Vout＝a0 vf0+a0 pf0+a2 pf2+a3 vf3+a4 pf4+a5 vf5+a6 pf6+a7 vf7+a8 pf8+a9 vf9+… (4)
from (1) and (4):
a0 vf0+a0 pf0＝a0f0(5)
a2 pf2＝a2f2；a4 pf4＝a4f4；a6 pf6＝a6f6；a8 pf8＝a8f8；… (6)
a3 vf3＝a3f3；a5 vf5＝a5f5；a7 vf7＝a7f7；a9 vf9＝a9f9；… (7)
since the fundamental frequencies used for transmitting the first signal and the second signal are the same and only the harmonic components are different, it can be known from (5):
therefore, the receiving end can demodulate all of the signal one and the signal two according to the equations (6) to (8).
5. The spatial division multiple access communication method based on the harmonic modulation technique as claimed in claim 2, wherein when the different information is modulated and then loaded on the different harmonic components for signal transmission, different combinations of the harmonic components can be selected for signal transmission according to requirements.
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| CN201911279169.4A CN111132334A (en) | 2019-12-13 | 2019-12-13 | Space division multiple access communication method based on harmonic modulation technology |
| LU102119A LU102119B1 (en) | 2019-12-13 | 2020-10-12 | Space division multiple access communication method based on harmonic modulation technology |
| NL2026741A NL2026741B1 (en) | 2019-12-13 | 2020-10-23 | Space division multiple access communication method based on harmonic modulation technology |
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| WO2021114749A1 (en) * | 2019-12-13 | 2021-06-17 | 广东工业大学 | Frequency division multiple address communication method based on harmonic modulation technology |
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| CN103338176A (en) * | 2013-06-13 | 2013-10-02 | 上海理工大学 | Implementation method of waveform reuse modulator-demodulator |
| US20160191138A1 (en) * | 2014-12-31 | 2016-06-30 | Nxp B.V. | Multiple antenna distributed radio system |
| CN106856460A (en) * | 2015-12-09 | 2017-06-16 | 北京信威通信技术股份有限公司 | Space division multiple access accessing user matching process and system |
| CN109471064A (en) * | 2018-09-18 | 2019-03-15 | 上海交通大学 | Time-modulation array df system based on pulse compression technique |
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| US5499270A (en) * | 1994-08-01 | 1996-03-12 | Pierre Charrier | Spectral encoding-decoding system and method thereof |
| US7190729B2 (en) * | 2002-07-26 | 2007-03-13 | Alereon, Inc. | Ultra-wideband high data-rate communications |
| US9136974B2 (en) * | 2005-08-30 | 2015-09-15 | Qualcomm Incorporated | Precoding and SDMA support |
| US8675779B2 (en) * | 2010-09-28 | 2014-03-18 | Landis+Gyr Technologies, Llc | Harmonic transmission of data |
| WO2018179010A1 (en) * | 2017-03-31 | 2018-10-04 | Tejas Networks Limited | Wavelength-based modulation of orthogonal frequencies |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103338176A (en) * | 2013-06-13 | 2013-10-02 | 上海理工大学 | Implementation method of waveform reuse modulator-demodulator |
| US20160191138A1 (en) * | 2014-12-31 | 2016-06-30 | Nxp B.V. | Multiple antenna distributed radio system |
| CN106856460A (en) * | 2015-12-09 | 2017-06-16 | 北京信威通信技术股份有限公司 | Space division multiple access accessing user matching process and system |
| CN109471064A (en) * | 2018-09-18 | 2019-03-15 | 上海交通大学 | Time-modulation array df system based on pulse compression technique |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021114749A1 (en) * | 2019-12-13 | 2021-06-17 | 广东工业大学 | Frequency division multiple address communication method based on harmonic modulation technology |
| US11902077B2 (en) | 2019-12-13 | 2024-02-13 | Guangdong University Of Technology | Frequency division multiple access communication method based on harmonic modulation technology |
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| NL2026741A (en) | 2021-08-17 |
| NL2026741B1 (en) | 2023-08-14 |
| LU102119B1 (en) | 2021-04-14 |
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