CN106102132B - Short wave networking realization method for short wave intelligent frequency selection and diversity - Google Patents
Short wave networking realization method for short wave intelligent frequency selection and diversity Download PDFInfo
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- CN106102132B CN106102132B CN201610408293.6A CN201610408293A CN106102132B CN 106102132 B CN106102132 B CN 106102132B CN 201610408293 A CN201610408293 A CN 201610408293A CN 106102132 B CN106102132 B CN 106102132B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W48/00—Access restriction; Network selection; Access point selection
- H04W48/16—Discovering, processing access restriction or access information
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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
- H04B7/022—Site diversity; Macro-diversity
- H04B7/024—Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
Abstract
The invention discloses a short-wave networking realization method for short-wave intelligent frequency selection and diversity, which comprises the steps of quickly selecting accessible frequency within specific time through short-wave intelligent frequency selection equipment, quickly establishing a link and improving the accessible rate of short-wave communication; and the received soft information is combined and analyzed through a diversity combining technology so as to obtain higher diversity gain and improve the quality of short-wave communication. The invention combines the advantages of the two technologies, integrates the intelligent frequency selection technology and the diversity technology, and is applied to the system realization of the short-wave networking.
Description
Technical Field
The invention relates to the field of short-wave communication research, in particular to a short-wave networking implementation method by using a short-wave intelligent frequency selection and diversity technology.
Background
The short-wave communication has the characteristics of long communication distance, difficulty in thorough destruction and the like, and is widely applied to the fields of military communication, public security frontier defense, emergency disaster relief, external traffic, ocean monitoring and the like of all countries in the world. In the future execution of diversified guarantee tasks, short-wave communication is an important communication means for guaranteeing the battle command, sometimes even the only communication means, and the importance of the short-wave communication is very remarkable. In order to prepare diversified task communication support, short-wave communication system equipment and network construction must be further enhanced, and comprehensive support capability of short-wave communication is improved, so that the requirement of diversified task communication support in the future is met.
The short-wave networking is based on the existing short-wave communication equipment and construction results, is based on the existing equipment and mature technology, and improves the communication equipment for transforming the existing short-wave fixed station and the mobile communication system through scientific planning and dynamic allocation of frequency resources to construct the short-wave networking of a unified system.
The existing shortwave communication access network is based on information construction, adheres to a networked development idea and is dragged and technically promoted according to requirements; comprehensive networking and system guarantee; machine-fixed integration and resource sharing; the short wave information transmission and exchange platform shared by civil and military people is formed by establishing the principle of the prior and the adjustment of the layout, fully utilizing the prior equipment and the existing network, and adopting the measures of combination of construction and modification, means synthesis, system fusion and network system integration.
The intelligent frequency selection technology is a new generation frequency selection link establishment technology designed based on cognitive radio and a new generation broadband multi-channel receiving technology, and can effectively shorten the frequency selection link establishment time, improve the frequency selection link establishment speed and improve the user experience.
The diversity reception technology is one of the most effective measures for resisting channel fading, and due to the time-varying property and multipath property of the short-wave channel, signals reach a receiving end through the short-wave channel and are seriously faded, so that the traditional short-wave communication reliability and the communication rate are lower. Common diversity methods are space diversity, frequency diversity and time diversity.
Patent CN201510952373.3 discloses a diversity reception method and system based on hard value decision of short wave access network, far-end user and a fixed station in the short wave access network carry out interaction and accomplish link establishment and network access, the fixed station sends operating frequency to control center, control center receives path number N of signal as required, select other N-1 fixed stations in the short wave access network, and set operating frequency, when signal transmission is required, far-end user sends signal, the fixed station processes and gathers the result to control center after judging, control center selects the decoding signal that any way check is successful as final signal output, if all fixed station checks are unsuccessful, it is failed to determine signal reception.
In the practical use process of the short-wave networking, the power asymmetry of the uplink and downlink radio stations causes low link establishment success rate, poor communication effect and poor user experience. Therefore, it is of great significance to find a short-wave networking implementation method for improving the link establishment success rate and the communication effect.
Disclosure of Invention
Based on the existing short-wave networking network architecture, the invention aims to improve the network access transmission performance of low-power radio station users, improve the success rate of service communication and reduce the communication rate, and builds an integrated short-wave networking communication system by relying on the technologies of intelligent frequency selection and chain building, diversity reception, broadband multichannel reception and the like, thereby achieving the effects of quick access, quick intercommunication and reliable transmission of mobile users.
A shortwave intelligent frequency selection and diversity shortwave networking realization method based on intelligent frequency selection and diversity reception is characterized in that: the short-wave networking implementation method comprises the following steps,
step one, establishing a wireless link between a mobile user and an access node: the mobile user is provided with intelligent frequency selection equipment, the intelligent frequency selection equipment controls a built-in broadband receiving module and an externally matched short-wave radio station, and bidirectional detection is carried out on an access node in a sliding window mode; the complete bidirectional detection process comprises two sub-processes of coarse detection and fine detection, wherein the coarse detection completes the initial contact of a signaling channel, and the fine detection completes the optimization of service communication frequency; on the premise of considering both the frequency selection speed and the frequency selection link establishment success rate, combining coarse detection and fine detection, selecting the communication frequency with the highest signal-to-noise ratio to form an optimal communication channel, and completing the frequency selection link establishment;
and step two, after the wireless link is successfully established, on the link establishment frequency, the diversity processing center designates other nodes except the access node of the established wireless link to assist diversity reception, and the diversity processing center combines and decodes signals received from all the nodes to realize diversity performance gain of service communication.
After receiving the call link establishment request, the access node reports the current frequency, the user ID and the channel score to the diversity processing center.
Preferably, the diversity processing center selects nodes with high signal-to-noise ratio, connection once performed, short geographical distance and antenna facing to mobile users to establish links according to the scores of the nodes, historical frequency experience and the position information of the nodes. The strategy of randomly selecting a certain idle access node for chain establishment by a traditional diversity processing center is optimized as follows:
(1) after each node receives the call link establishment request, reporting the current frequency, the user ID and the channel score to a diversity processing center;
(2) the diversity processing center selects the best node to build the chain according to the information such as the score of each current node, the historical frequency experience, the position of the node and the like,
by using the method, the transmission quality of the wireless link can be improved.
Preferably, the access node of the wireless link is a master node and adopts a narrow-band receiving mode, and the other nodes are auxiliary diversity access nodes and adopt a broadband receiving mode; on one hand, the main node exclusively receives the information of the mobile user, and on the other hand, other auxiliary diversity access nodes can simultaneously provide auxiliary diversity reception for a plurality of users, thereby greatly improving the diversity path number and the concurrent access capability of the system.
Preferably, in the short-wave networking implementation method, virtual circuit addresses are used to avoid collision among different users, a plurality of mobile users can share channel resources by adopting a method of 'sharing channel resources-long-time online-random occupation-release after use', and backoff or frequency change is controlled by upper-layer control logic if collision occurs. Under the condition of multiple users, firstly demodulating each path of signal to identify a virtual circuit, judging each path of signal according to a certain rule (such as balanced signal-to-noise ratio, multipath number, single-path demodulation condition and the like) for the rest parts which can be successfully demodulated by a single-path demodulation by using a selection combination strategy, and selecting useful signals to carry out maximum ratio combination.
Preferably, when the virtual circuit address is used in the operating mode, each frame of data packet sent by the mobile user must contain user address information (including the local address and the address thereof), so that the access node side can effectively identify and distinguish different users.
Preferably, the fast frequency selection device is a fast access unit or a user access controller.
Preferably, diversity reception supports multiple diversity.
Compared with the prior art, the invention has the following advantages and beneficial effects:
1. the invention integrates frequency selection diversity, takes the advantages of each frequency selection diversity, effectively solves the problem of asymmetry of short-wave communication from top to bottom and improves the effect of short-wave communication;
2. the invention is applied to the realization of short-wave networking, and optimizes and promotes the diversity reception mode applied to large-scale networking;
3. the invention provides a solution of virtual circuit for multi-user conflict problem in the application process of the group network, which makes large-scale expansion application possible;
4. the diversity multiplicity of the present invention supports spreading.
Drawings
Fig. 1 is a basic structural diagram of a short-wave networking method;
FIG. 2 is a schematic diagram of a frequency-selective and diversity-based short-wave networking;
FIG. 3 is a schematic diagram of the fast frequency-selecting operation principle;
FIG. 4 is a flow chart of an intelligent frequency-selecting link-building process (without pre-frequency planning);
FIG. 5 is a flow chart of an intelligent frequency-selecting link-building process (with pre-frequency planning);
FIG. 6 is a schematic diagram of a diversity reception combining process;
fig. 7 is a diagram illustrating user identification at the access node side.
Detailed Description
The following further describes embodiments of the present invention with reference to the accompanying drawings:
as shown in fig. 1 and fig. 2, the present invention uses an intelligent frequency selection technology and a diversity reception technology, and a radio link is established between a user side radio station and an access node side radio station through broadband reception and intelligent frequency selection between a mobile user and the access node:
the short-wave networking realization method comprises the following steps,
step one, establishing a wireless link between a mobile user and an access node: the mobile user is provided with intelligent frequency selection equipment, and only the frequency selection equipment can control a built-in broadband receiving module and an externally matched short-wave radio station to perform bidirectional detection on the access node in a sliding window mode; as shown in fig. 3, the complete bidirectional probing process includes two sub-processes of coarse probing and fine probing, the coarse probing completes the initial contact of the signaling channel, and the fine probing completes the optimization of the service communication frequency; on the premise of considering both the frequency selection speed and the frequency selection link establishment success rate, combining coarse detection and fine detection, selecting the communication frequency with the highest signal-to-noise ratio to form an optimal communication channel, and completing the frequency selection link establishment;
and step two, after the wireless link is successfully established, on the link establishment frequency, the diversity processing center designates other nodes except the access node of the established wireless link to assist diversity reception, and the diversity processing center combines and decodes signals received from all the nodes to realize diversity performance gain of service communication.
After each node receives the call link establishment request, the current frequency, the user ID and the channel score are reported to the diversity processing center.
As shown in fig. 4, in an embodiment of the present invention, an intelligent frequency-selecting link-building process without a pre-frequency planning needs to perform an uplink frequency set coarse probing, a coarse probing confirmation (a downlink frequency fine probing scheme), automatically form a frequency fine probing scheme, a downlink frequency fine probing, an uplink frequency fine probing (a downlink frequency-selecting result), and complete link building (an uplink frequency-selecting result) according to a coarse probing reception result.
As shown in fig. 5, in an embodiment of the present invention, there is an intelligent frequency-selecting chain establishment process with a pre-frequency planning, and a mobile user waits for a predetermined frequency set without performing a coarse-probing and fine-probing process, and completes the chain establishment after sequentially probing an uplink frequency set and a downlink frequency set.
As shown in fig. 6, in an embodiment of the present invention, a diversity processing center selects an optimal node for link establishment according to a score of each node, historical frequency experience, and location information to which the node belongs, and optimizes a policy that a conventional diversity processing center randomly selects a certain idle access node for link establishment as follows:
(1) after each node receives the call link establishment request, reporting the current frequency, the user ID and the channel score to a diversity processing center;
(2) and the diversity processing center selects the optimal node to establish a link according to the information such as the score of each current node, historical frequency experience, the position of the node and the like.
After the short-wave wireless link is established between the mobile user and the access node, various service transmission can be carried out based on the diversity reception technology. In the invention, the diversity technology adopts uplink receiving diversity, wherein the receiving diversity refers to that a sending end radio station transmits signals on a certain frequency point, a plurality of receiving ends of different access nodes (or a plurality of receivers of the same access node) receive a plurality of independent signal copies bearing the same information, and because each signal cannot be in deep fading at the same time, a proper combination mode can be adopted to obtain higher diversity gain. As shown in detail.
The transmitting end transmits the signal on a certain frequency point after coding modulation, each receiving end processes the received data, and then the data is converged to a diversity processing center through a network for combination processing. In the actual engineering implementation, in order to reduce the data transmission amount in the network, each receiving end converges the data (soft information for short) before decoding after demodulation to the diversity processing center through the network for merging processing. In the short-wave network diversity, the distance between the antennas of different nodes can reach hundreds of kilometers to thousands of kilometers, the short-wave signals received by a plurality of antennas are ensured to have independent fading characteristics to the maximum extent, and a certain diversity gain is obtained through a certain combination technology, so that the short-wave communication quality is ensured.
In one embodiment of the invention, the access node of the wireless link is a main node and adopts a narrow-band receiving mode, and other nodes are auxiliary diversity access nodes and adopt a broadband receiving mode; on one hand, the main node exclusively receives the information of the mobile user, and on the other hand, other auxiliary diversity access nodes can simultaneously provide auxiliary diversity reception for a plurality of users, thereby greatly improving the diversity path number and the concurrent access capability of the system.
In one embodiment of the invention, in the short-wave networking implementation method, virtual circuit addresses are used for avoiding collision among different users, a plurality of mobile users can share channel resources by adopting a method of 'sharing channel resources-long-time online-random occupation-release after use', and backoff or frequency change is controlled by upper-layer control logic if collision occurs. Under the condition of multiple users, firstly demodulating each path of signal to identify a virtual circuit, judging each path of signal according to a certain rule (such as balanced signal-to-noise ratio, multipath number, single-path demodulation condition and the like) for the rest parts which can be successfully demodulated by a single-path demodulation by using a selection combination strategy, and selecting useful signals to carry out maximum ratio combination.
As shown in fig. 7, in an embodiment of the present invention, in order to realize accurate mobile user identification, when decoding, the diversity processing center first performs single-path decoding on each path of information, and identifies information sent by the mobile user, which can be obtained by the single-path decoding; then, merging and decoding the signals which cannot be successfully decoded in the single path, and identifying the information sent by other mobile users (if the information is the same as the information sent by the mobile users in the single path decoding, discarding the information); and finally, taking a union set and outputting the information sent by all the mobile users (only one copy of information is output for each mobile user).
In one embodiment of the present invention, when the virtual circuit address operation mode is used, each frame of data packet sent by the mobile user must contain user address information (including the local address and its address), so that the access node side can effectively identify and distinguish different users.
In one embodiment of the invention, diversity reception supports multiple diversity.
Variations and modifications to the above-described embodiments may occur to those skilled in the art, which fall within the scope and spirit of the above description. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and variations of the present invention should fall within the scope of the claims of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
Claims (7)
1. A shortwave intelligent frequency selection and diversity shortwave networking realization method based on intelligent frequency selection and diversity reception is characterized in that: the short-wave networking implementation method comprises the following steps,
step one, establishing a wireless link between a mobile user and an access node: the mobile user is provided with intelligent frequency selection equipment, the intelligent frequency selection equipment controls a built-in broadband receiving module and an externally matched short-wave radio station, and bidirectional detection is carried out on an access node in a sliding window mode; the complete bidirectional detection process comprises two sub-processes of coarse detection and fine detection, wherein the coarse detection completes the initial contact of a signaling channel, and the fine detection completes the optimization of service communication frequency; on the premise of considering both the frequency selection speed and the frequency selection link establishment success rate, combining coarse detection and fine detection, selecting the communication frequency with the highest signal-to-noise ratio to form an optimal communication channel, and completing the frequency selection link establishment;
after the wireless link is successfully established, on the link establishment frequency, the diversity processing center designates other nodes except the access node of the established wireless link to assist diversity reception, and the diversity processing center combines and decodes signals received from all the nodes to realize diversity performance gain of service communication;
wherein, if there is no pre-frequency planning, the first step further comprises the following steps:
s1: roughly detecting an uplink frequency set;
s2: performing rough detection confirmation;
s3: setting a fine sounding frequency set and waiting at a fixed frequency;
s4: fine detection of downlink frequency;
s5: fine detection of uplink frequency;
if the frequency planning is carried out in advance, the first step does not need to carry out a coarse probing and fine probing process and comprises the following steps:
s1': keeping constant frequency in a set frequency set;
s2': detecting an uplink frequency set;
s3': and detecting a downlink frequency set.
2. The short-wave networking implementation method of claim 1, wherein: and after receiving the call link establishment request, the access node reports the current frequency, the user ID and the channel score to the diversity processing center.
3. The short-wave networking implementation method of claim 1, wherein: and the diversity processing center selects nodes with high signal-to-noise ratio, connection once performed, short geographical distance and antenna orientation to the mobile user to establish a link according to the score of each node, historical frequency experience and the position information of the node.
4. The short-wave networking implementation method of claim 1, wherein: the access node of the wireless link is a main node and adopts a narrow band receiving mode, and other nodes are auxiliary diversity access nodes and adopt a broadband receiving mode.
5. The short-wave networking implementation method of claim 1, wherein: in the short wave networking realization method, virtual circuit addresses are used for avoiding collision among different users, a plurality of mobile users share channel resources and are always online, the channel resources can be randomly occupied and released after use, and backoff or frequency conversion is controlled by upper control logic if collision conflicts occur.
6. The short-wave networking implementation method of claim 5, wherein: when the virtual circuit address is used in the working mode, each frame of data packet sent by the mobile user must contain user address information, and the user address information contains the local address and other addresses.
7. The short-wave networking implementation method of claim 1, wherein: the diversity reception supports multiple diversity.
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| CN106712828B (en) * | 2016-11-25 | 2020-08-04 | 西安烽火电子科技有限责任公司 | Geographical diversity receiving system and method of short wave frequency |
| CN106878943B (en) * | 2017-01-11 | 2019-08-23 | 中国人民解放军国防信息学院 | Short wave network Situation Awareness realization method and system |
| CN109152060A (en) * | 2018-09-26 | 2019-01-04 | 中国人民解放军陆军工程大学 | Transmitter channel distribution model and method in a kind of shortwave downlink communication |
| CN109348484B (en) * | 2018-11-28 | 2022-02-18 | 中国人民解放军陆军工程大学 | Multi-user short-wave communication network model and channel detection method |
| CN110636591B (en) * | 2019-10-16 | 2021-06-22 | 中国人民解放军国防科技大学 | Method for quickly selecting frequency and establishing link and transmitting voice service in short wave access network |
| CN111711474B (en) * | 2020-06-08 | 2024-04-05 | 中国人民解放军96872部队 | Short wave antenna optimization system |
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