CN113612520B - VDES communication method utilizing rapid satellite search and on-satellite frequency offset processing - Google Patents

VDES communication method utilizing rapid satellite search and on-satellite frequency offset processing Download PDF

Info

Publication number
CN113612520B
CN113612520B CN202110899906.1A CN202110899906A CN113612520B CN 113612520 B CN113612520 B CN 113612520B CN 202110899906 A CN202110899906 A CN 202110899906A CN 113612520 B CN113612520 B CN 113612520B
Authority
CN
China
Prior art keywords
satellite
ship
frequency offset
low
orbit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202110899906.1A
Other languages
Chinese (zh)
Other versions
CN113612520A (en
Inventor
李洪星
丁晓光
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shandong Xingtong Easy Aviation Communication Technology Co ltd
Original Assignee
Shandong Xingtong Easy Aviation Communication Technology Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shandong Xingtong Easy Aviation Communication Technology Co ltd filed Critical Shandong Xingtong Easy Aviation Communication Technology Co ltd
Priority to CN202110899906.1A priority Critical patent/CN113612520B/en
Publication of CN113612520A publication Critical patent/CN113612520A/en
Application granted granted Critical
Publication of CN113612520B publication Critical patent/CN113612520B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/185—Space-based or airborne stations; Stations for satellite systems
    • H04B7/1851—Systems using a satellite or space-based relay
    • H04B7/18513—Transmission in a satellite or space-based system
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/185—Space-based or airborne stations; Stations for satellite systems
    • H04B7/19—Earth-synchronous stations
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L67/00—Network arrangements or protocols for supporting network services or applications
    • H04L67/01—Protocols
    • H04L67/12—Protocols specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Abstract

The invention relates to a VDES communication method using rapid satellite search and on-satellite frequency offset processing, which comprises the following steps: collecting related data by a geosynchronous satellite; calculation of optimal access low-orbit satellite j of ship i by geosynchronous satellite * (ii) a Direct search and access to satellite j for ship i * (ii) a Ship i direction satellite j * Transmitting data, satellite j * Carrying out on-satellite frequency offset processing on the received data and forwarding the data to a ground receiving station; and the ground receiving station performs frequency offset processing and judgment on the received data. Compared with the existing method for searching the low orbit satellite in an all-round and full-elevation way, the method disclosed by the invention can realize the rapid satellite searching of the ship, reduce the communication access time delay and ensure the real-time performance of data transmission. Compared with the existing method for performing frequency offset estimation and correction only on a ground receiving station, the method disclosed by the invention increases the on-satellite frequency offset estimation and correction of the low orbit satellite, can reduce the possibility of final frequency offset estimation failure, and can reduce the frequency offset estimation error.

Description

VDES communication method utilizing rapid satellite search and on-satellite frequency offset processing
Technical Field
The invention belongs to the technical field of wireless communication, and particularly relates to a VDES communication method utilizing rapid satellite search and on-satellite frequency offset processing.
Background
With the prosperity of the marine transportation industry, the demand of maritime communication is increasing, and the existing Automatic Identification System (AIS) of ships is congested and cannot meet the demand of diversified information transmission, so that the International Association of navigation systems (IALA) proposes a very high frequency Data Exchange System (VHF Data Exchange System, VDES). The VDES is a three-in-one global data exchange system, and the air part of the VDES is an air network composed of high-orbit satellites and low-orbit satellites, wherein the high-orbit satellites refer to geostationary satellites, the VDES uses the geostationary satellites to assist positioning and navigation, and the low-orbit satellites are used to rapidly transmit data.
When the VDES transmits data by using a low-orbit satellite, the low-orbit satellite generally serves as a relay to forward data to a ship, for example, data transmitted by the ship is forwarded to a ground receiving station or other ships via the low-orbit satellite. Before a ship sends data, an optimal access low orbit satellite needs to be searched for uplink access, the IALA G1139 recommendation and the existing documents adopt the traditional omnibearing and full-elevation low orbit satellite searching method so as to search the optimal access low orbit satellite, the satellite searching method consumes communication and calculation resources of a ship terminal, the searching time is long, the access is slow, the time delay of data transmission is long, and the requirement of real-time data transmission cannot be met. Therefore, how to design a rapid satellite searching method for a ship to reduce the access delay of communication and ensure the real-time performance of data transmission is a key problem to be solved at present.
In addition, the low-orbit satellite has a relatively high movement speed with respect to the ground, so that doppler frequency shifts between the ship and the low-orbit satellite and between the low-orbit satellite and the ground receiving station are relatively large, and frequency offset estimation and correction are required in the communication process. There are documents such as "research on QPSK signal synchronous parameter estimation in VDES" (author velcade, university of tianjin university of kingdom academic thesis, 03 month 2019) and "research on frequency offset estimation and phase tracking algorithm in VDES" (author fanjiahui, electronic measurement technology, vol 43, 23, 12 months 2020, pages 51-56) that provide some conventional frequency offset estimation methods, such as Fitz algorithm, L & R algorithm, and M & M algorithm, and indicate that these methods can be used in VDES system, however, these frequency offset estimation methods are all frequency offset estimation and correction for downlink from low-orbit satellite to ship, or from low-orbit satellite to ground receiving station. For a complete ship-satellite-ground receiving station link, it is not appropriate to use these traditional frequency offset estimation methods only on the ground receiving station, the main reason is that the complete link includes two links, namely an uplink link and a downlink link, and the frequency offset is the superposition of the uplink frequency offset and the downlink frequency offset, and is easily beyond the estimation range of the traditional frequency offset estimation methods, so the use of these traditional frequency offset estimation methods easily causes the problems of frequency offset estimation failure, inaccurate received signal, communication quality degradation, and the like. Although in the conventional method, the low-orbit satellite is only used as a forwarding relay, at present, most low-orbit satellites are equipped with more and more advanced devices, such as improved power supplies, powerful chips and circuit boards, and the like, and have stronger on-board processing capacity. None of the existing literature and research has considered reducing the frequency offset estimation failure probability and reducing the frequency offset estimation error in communication by relaying on-board processing on low orbit satellites.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a VDES communication method utilizing fast satellite search and on-satellite frequency offset processing, which can realize fast satellite search of ships, reduce the possibility of frequency offset estimation failure and reduce frequency offset estimation errors by relaying on-satellite frequency offset processing on low orbit satellites.
The scheme for solving the technical problems is as follows:
a VDES communication method using fast satellite search and on-satellite frequency offset processing, the method includes the following steps:
the method comprises the following steps: geosynchronous satellite collection of correlated data
Setting the number of low orbit satellites as M and the number of ships as N; if a ship i in the N ships needs to send data to a ground receiving station, the ship i needs to forward the data to the ground receiving station by means of a low orbit satellite, wherein i belongs to {1,2, \8230;, N }; the ship i needs to send the position, navigation direction, navigation speed and service requirement information of the ship i to a high orbit satellite, namely a geostationary satellite; all low-orbit satellites need to periodically report the own orbit, operation speed and current position to the geostationary satellite; the geosynchronous satellite records and stores the information;
step two: calculation of optimal access low-orbit satellite j of ship i by geosynchronous satellite *
According to the collected data, the geosynchronous satellite calculates the optimal access low-orbit satellite j of the ship i * Access direction, access elevation, and ship i to said satellite j * And sends these calculations to vessel i and satellite j * The specific process is as follows:
according to the collected data, the geosynchronous satellite calculates the Doppler frequency shift from the ship i to all low-orbit satellites according to a calculation formula
Figure BDA0003198334460000031
Wherein +>
Figure BDA0003198334460000032
For the Doppler shift of a ship i to a low orbit satellite j, j ∈ {1,2, \8230;, M }, λ i For transmitting electromagnetic wave wavelength, v, of ship i ij Is the relative movement velocity, θ, of the vessel i and the low orbit satellite j ij Representing the included angle between the connecting line of the ship i and the low orbit satellite j and the movement direction of the ship i;
finding out a satellite j according to the Doppler frequency shift from the ship i to all low orbit satellites * And according to satellite j * And the position of the ship i obtains the position of the ship i relative to the satellite j * Access direction and access elevation angle
Figure BDA0003198334460000033
Wherein->
Figure BDA0003198334460000034
And j is * E {1,2, \8230;, M }, i.e., ship i to satellite j * Is Doppler shift of->
Figure BDA0003198334460000035
The calculated optimal access of the ship i to the low-orbit satellite j by the geosynchronous satellite * Access direction, access elevation, and ship i to satellite j * Respectively sent to the ship i and the satellite j * ；
Step three: direct search and access to satellite j for ship i *
The ship i receives the calculation result sent by the geosynchronous satellite, and directly searches and accesses the satellite j according to the access direction and the access elevation angle in the calculation result * ；
Step four: ship i direction satellite j * Transmitting data, satellite j * The received data is carried out the frequency deviation processing on the satellite and is forwarded to the ground receiving station
Ship i-direction satellite j * Transmitting data, satellite j * Carrying out satellite frequency offset processing on received data, wherein the specific process of the satellite frequency offset processing is as follows:
in turn according to
Figure BDA0003198334460000041
Pre-correction of frequency offset, matched filtering and symbol synchronization, then using existing frequency offset estimation methods, e.g., fitz's algorithm, L&R Algorithm or M&Performing frequency offset estimation and frequency offset re-correction by using an M algorithm; satellite j * Transmitting the signals after the frequency offset processing to a ground receiving station in an amplifying and transmitting mode;
step five: the ground receiving station processes the frequency deviation of the received data and judges the received data
The ground receiving station carries out frequency offset estimation and correction of a downlink on the received data by using the existing frequency offset estimation method, and then carries out decision reduction on the processed data.
The invention discloses a VDES communication method by utilizing rapid satellite searching and on-satellite frequency offset processing, which has the following beneficial effects compared with the prior art:
1. through the combination of the low-orbit satellite and the geosynchronous satellite, the geosynchronous satellite is utilized to assist in the searching and accessing of the low-orbit satellite. Firstly, the optimal access low orbit satellite, the access direction, the access elevation angle and the like of the ship are calculated on the geosynchronous satellite, then the results are sent to the ship, and the ship directly searches and accesses the optimal access low orbit satellite according to the access direction and the access elevation angle. Compared with the existing method for searching the low orbit satellite in the omnibearing and full elevation angle mode of the ship, the method can realize quick satellite searching, reduce the access time delay of communication and ensure the real-time performance of data transmission.
2. The frequency offset of the uplink is estimated and corrected through satellite processing of the relay low-orbit satellite, namely, the frequency offset of the uplink is estimated and corrected on the relay low-orbit satellite, and then the frequency offset is forwarded. Therefore, finally, the Doppler frequency shift of the ground receiving end is mainly generated by the downlink, the Doppler frequency shift of the uplink is corrected at the relay low-orbit satellite, and the ground receiving end only needs to be responsible for frequency offset estimation and correction of the downlink. Thus, the complete link is divided into an uplink section and a downlink section, and the frequency offset of the uplink and the downlink is estimated and corrected respectively. Compared with the existing method of only performing frequency offset estimation and correction on the ground receiving station, the satellite frequency offset processing can reduce the possibility of final frequency offset estimation failure, reduce frequency offset estimation errors and improve the accuracy of receiving signals by the ground receiving terminal.
Drawings
FIG. 1 is a general flow diagram of a VDES communication method using fast satellite search and on-satellite frequency offset processing according to the present invention;
FIG. 2 is a schematic diagram of a system model of a VDES communication method using fast satellite search and on-satellite frequency offset processing according to the present invention;
FIG. 3 is a block diagram of an on-satellite frequency offset processing flow in a VDES communication method using fast satellite search and on-satellite frequency offset processing according to the present invention;
FIG. 4 is a diagram of simulation results of mean square error estimation of frequency offset in a VDES communication method using fast satellite search and on-satellite frequency offset processing according to the present invention;
Detailed Description
The invention will be further explained with reference to the drawings.
Example 1
As shown in fig. 1, the VDES communication method using fast satellite search and on-satellite frequency offset processing disclosed in the present invention includes the following steps:
the method comprises the following steps: geosynchronous satellite collection of correlated data
Setting the number of low orbit satellites as M and the number of ships as N; as shown in fig. 2, if a ship i of the N ships needs to send data to a ground receiving station, the ship i needs to forward the data to the ground receiving station by means of a low orbit satellite, wherein i ∈ {1,2, \8230;, N }; the ship i needs to send the position, navigation direction, navigation speed and service requirement information of the ship i to a high orbit satellite, namely a geostationary satellite; all low-orbit satellites need to periodically report the own orbit, operation speed and current position to the geostationary satellite; the geosynchronous satellite records and stores the information;
step two: calculation of optimal access low orbit satellite j of ship i by geosynchronous satellite *
According to the collected data, the geosynchronous satellite calculates the optimal access low-orbit satellite j of the ship i * Access direction, access elevation, and ship i to said satellite j * And sends these calculations to vessel i and satellite j * The specific process comprises the following steps:
according to the collected data, the geosynchronous satellite calculates the Doppler frequency shift from the ship i to all low-orbit satellites according to a calculation formula
Figure BDA0003198334460000061
Wherein->
Figure BDA0003198334460000062
Is the Doppler shift of the ship i to the low orbit satellite j, j ∈ {1,2, \8230;, M }, λ ∈ [ ], and i for transmitting electromagnetic wave wavelength, v, of ship i ij Is the relative movement velocity, θ, of the vessel i and the low orbit satellite j ij The included angle between the connecting line of the ship i and the low orbit satellite j and the movement direction of the ship i is shown;
finding out a satellite j according to the Doppler frequency shift from the ship i to all low-orbit satellites * And according to satellite j * And the position of the ship i obtains the position of the ship i relative to the satellite j * Access direction and access elevation angle
Figure BDA0003198334460000063
Wherein->
Figure BDA0003198334460000064
And j is * E {1,2, \8230;, M }, i.e., ship i to satellite j * Is Doppler shift of->
Figure BDA0003198334460000065
The calculated optimal access of the ship i to the low-orbit satellite j by the geosynchronous satellite * Access direction, access elevation angle, toAnd ship i to satellite j * Respectively sent to the ship i and the satellite j * ；
Step three: direct search and access to satellite j for ship i *
The ship i receives the calculation result sent by the geosynchronous satellite, and directly searches and accesses the satellite j according to the access direction and the access elevation angle in the calculation result * ；
Step four: ship i-direction satellite j * Transmitting data, satellite j * The received data is carried out the on-satellite frequency deviation processing and is forwarded to the ground receiving station
Ship i direction satellite j * Transmitting data, satellite j * Performing satellite frequency offset processing on received data, wherein a flow chart of the satellite frequency offset processing is shown in fig. 3, and the specific process is as follows:
in turn according to
Figure BDA0003198334460000071
Pre-correction of frequency offset, matched filtering and symbol synchronization, then using existing frequency offset estimation methods, e.g., fitz's algorithm, L&R Algorithm or M&Performing frequency offset estimation and frequency offset re-correction by using an M algorithm; satellite j * Transmitting the signals after the frequency offset processing to a ground receiving station in an amplifying and transmitting mode;
step five: the ground receiving station processes the frequency deviation of the received data and judges the received data
The ground receiving station carries out frequency offset estimation and correction of a downlink on the received data by using the existing frequency offset estimation method, and then carries out decision reduction on the processed data.
Example 2 (Experimental example)
According to the communication method utilizing the fast satellite search and the on-satellite frequency offset processing, disclosed by the invention, a simulation experiment is carried out, and the frequency offset estimation added with the on-satellite frequency offset processing is compared with the traditional frequency offset estimation, so that the feasibility and the effectiveness of the method are demonstrated.
In simulation, the channel is set as AWGN channel, QPSK modulation is carried out, the orbit height of the low-orbit satellite is 600km, and the length of the training sequence is 48bit, symbol duration of
Figure BDA0003198334460000072
And in order to compare the frequency offset estimation processed by the satellite frequency offset with the traditional frequency offset estimation, the total frequency offset of the uplink and the downlink is set to be 500Hz, and the information transmission rate is 9600bit/s.
The simulation result is shown in fig. 4, wherein the "conventional L & R algorithm" refers to a method for performing L & R frequency offset estimation only at a ground receiving station without adding satellite frequency offset processing; the on-satellite frequency offset processing + L & R algorithm refers to the frequency offset estimation method added with the on-satellite frequency offset processing disclosed by the invention, and the existing frequency offset estimation related in the process adopts the traditional L & R algorithm; the "cramer-circle" is the lower boundary of the frequency offset estimate. When the conventional Fitz algorithm and M & M algorithm are adopted for frequency offset estimation, similar results to those of the L & R algorithm are obtained, and therefore details are not described in simulation results.
In fig. 4, the abscissa represents the signal-to-noise ratio, and the ordinate represents the mean square error of the frequency offset estimation of the complete link. As can be seen from fig. 4, as the signal-to-noise ratio increases, the mean square error of the frequency offset estimation of the "conventional L & R algorithm" and the "on-satellite frequency offset processing + L & R algorithm" decreases. The on-satellite frequency offset processing and L & R algorithm disclosed by the invention is closer to the Cramer-Rao bound and is obviously superior to the traditional L & R algorithm. The Doppler frequency shift of the uplink is corrected at the relay low orbit satellite through the on-satellite frequency shift processing, and the ground receiving station only needs to be responsible for the frequency shift estimation and correction of the downlink, so that the complete link is divided into an uplink section and a downlink section, the uplink frequency shift and the downlink frequency shift are respectively estimated and processed, the frequency shift estimation error of the whole link can be reduced, and the accuracy of received signals is improved. And the frequency offset value of each section is small and cannot exceed the estimation range of the traditional frequency offset estimation method, so that the probability of frequency offset estimation failure can be reduced.
In conclusion, compared with the existing omnibearing full-elevation star searching method, the VDES communication method utilizing the rapid star searching and the on-satellite frequency offset processing can realize the rapid star searching of ships, reduce the access time delay and ensure the real-time performance of data transmission; compared with the existing method for performing frequency offset estimation and correction only on the ground receiving station, the method increases the satellite frequency offset estimation and correction of the relay low-orbit satellite, can reduce the possibility of final frequency offset estimation failure of the ground receiving station, and reduces the frequency offset estimation error.

Claims (1)

1. A VDES communication method using fast satellite search and on-satellite frequency offset processing, the method includes the following steps:
the method comprises the following steps: geosynchronous satellite collection of correlated data
Setting the number of low orbit satellites as M and the number of ships as N; if a ship i in the N ships needs to send data to a ground receiving station, the ship i needs to forward the data to the ground receiving station by means of a low orbit satellite, wherein i belongs to {1,2, \8230;, N }; the ship i needs to send the position, navigation direction, navigation speed and service requirement information of the ship i to a high orbit satellite, namely a geostationary satellite; all low-orbit satellites need to periodically report the own orbit, operation speed and current position to the geostationary satellite; the geosynchronous satellite records and stores the information;
step two: calculation of optimal access low-orbit satellite j of ship i by geosynchronous satellite *
According to the collected data, the geosynchronous satellite calculates the optimal access low-orbit satellite j of the ship i * Access direction, access elevation, and ship i to said satellite j * And sends the calculation results to the ship i and the optimal access low orbit satellite j simultaneously * The specific process is as follows:
according to the collected data, the geosynchronous satellite calculates the Doppler frequency shift from the ship i to all low-orbit satellites according to a calculation formula
Figure FDA0004083340970000011
Wherein +>
Figure FDA0004083340970000012
Is the Doppler shift of the ship i to the low orbit satellite j, j ∈ {1,2, \8230;, M }, λ ∈ [ ], and i for transmitting electromagnetic wave wavelength, v, of ship i ij Is the relative motion velocity, θ, of the vessel i and the low orbit satellite j ij Representing the included angle between the connecting line of the ship i and the low orbit satellite j and the movement direction of the ship i;
finding out a satellite j according to the Doppler frequency shift from the ship i to all low-orbit satellites * And according to satellite j * And the position of the ship i obtains the position of the ship i relative to the satellite j * Access direction and access elevation angle
Figure FDA0004083340970000013
Wherein->
Figure FDA0004083340970000014
And j is * E {1,2, \8230;, M }, i.e., ship i to satellite j * Doppler of frequency shift is->
Figure FDA0004083340970000015
The calculated optimal access of the ship i to the low-orbit satellite j by the geosynchronous satellite * Access direction, access elevation, and ship i to satellite j * Respectively sent to the ship i and the satellite j * ；
Step three: direct search and access to satellite j for ship i *
The ship i receives the calculation result sent by the geosynchronous satellite, and directly searches and accesses the satellite j according to the access direction and the access elevation angle in the calculation result * ；
Step four: ship i direction satellite j * Transmitting data, satellite j * The received data is carried out the frequency deviation processing on the satellite and is forwarded to the ground receiving station
Ship i direction satellite j * Transmitting data, satellite j * Carrying out satellite frequency offset processing on received data, wherein the specific process of the satellite frequency offset processing is as follows:
in turn according to
Figure FDA0004083340970000021
Pre-correcting frequency offset, matching filtering and code element synchronization, and then utilizing Fitz algorithm and L&R Algorithm or M&Performing frequency offset estimation and frequency offset re-correction by using an M algorithm; satellite j * Transmitting the signals after the frequency offset processing to a ground receiving station in an amplifying and transmitting mode;
step five: the ground receiving station carries out frequency deviation processing and judgment on the received data
The ground receiving station carries out frequency offset estimation and correction of a downlink on the received data by using the existing frequency offset estimation method, and then carries out decision reduction on the processed data.
CN202110899906.1A 2021-08-05 2021-08-05 VDES communication method utilizing rapid satellite search and on-satellite frequency offset processing Active CN113612520B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110899906.1A CN113612520B (en) 2021-08-05 2021-08-05 VDES communication method utilizing rapid satellite search and on-satellite frequency offset processing

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110899906.1A CN113612520B (en) 2021-08-05 2021-08-05 VDES communication method utilizing rapid satellite search and on-satellite frequency offset processing

Publications (2)

Publication Number Publication Date
CN113612520A CN113612520A (en) 2021-11-05
CN113612520B true CN113612520B (en) 2023-04-14

Family

ID=78339575

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110899906.1A Active CN113612520B (en) 2021-08-05 2021-08-05 VDES communication method utilizing rapid satellite search and on-satellite frequency offset processing

Country Status (1)

Country Link
CN (1) CN113612520B (en)

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101420253A (en) * 2008-12-05 2009-04-29 航天恒星科技有限公司 Doppler compensation method for full arch satellite remote control
JP2018174491A (en) * 2017-03-31 2018-11-08 Ｎｅｃスペーステクノロジー株式会社 Artificial satellite
CN109120561B (en) * 2018-06-27 2021-03-02 东南大学 Medium frequency offset correction method for low-orbit satellite mobile communication system
CN110012558B (en) * 2019-04-09 2022-06-03 亚太卫星宽带通信（深圳）有限公司 Satellite network architecture with network reconfiguration capability
CN110545136B (en) * 2019-07-31 2021-11-23 上海众睿通信科技有限公司 Method for estimating and compensating uplink carrier frequency offset of low-orbit satellite multi-carrier communication system

Also Published As

Publication number Publication date
CN113612520A (en) 2021-11-05

Similar Documents

Publication Publication Date Title
US7764753B2 (en) Apparatus and method for adaptive wireless channel estimation
CN109379167A (en) Near-earth remote sensing satellite self-adapting changeable coding modulation data Transmission system and method
US11445393B2 (en) Method and device for adjusting at least one parameter of a communication system
KR20130074901A (en) Maritime communication system and method
US11677493B2 (en) System and method for predictive link planning
CN102893538A (en) Hybrid satellite and mesh network system for aircraft and ship internet service
CN110071756A (en) A kind of rotor block under burst signal detection and carrier synchronization method
CN105610761B (en) A kind of spaceborne GMSK bit error rate improvement system based on the system-level constraint of application layer
CN105119701B (en) A kind of low complex degree synchronous method of satellite AIS ship oceangoing ship positioning system
CN110187368A (en) Doppler shift processing method between low orbit satellite and ground based terminal
WO2019079798A1 (en) Metadata-based emitter localization
CN108135029A (en) A kind of method, apparatus and system applied to high-speed mobile communications
CN113612523A (en) Uplink time precompensation algorithm, terminal synchronization method and system
CN110289893B (en) Data transmission method based on cooperation among ships in VDES system
CN113612520B (en) VDES communication method utilizing rapid satellite search and on-satellite frequency offset processing
CN110445530B (en) Airborne object networking terminal and information transmission method
CN110113138B (en) Ocean VMS data transmission optimization method based on edge calculation
CN109600157A (en) A kind of adaptive quadrature recovery coding method based on signal-to-noise ratio (SNR) estimation
CN111431578B (en) AIS-based adaptive communication method for near space airship and ship
CN110429972B (en) Shipborne Internet of things terminal and information transmission method
CN109560856B (en) Beidou short message weapon data chain system for severe flight dynamic environment
CN111314007A (en) Frame synchronization system and method for TDMA multiple access
CN113965298B (en) Communication method of dual-channel unmanned aerial vehicle line-of-sight communication system
CN115173931A (en) Satellite-based VHF system and communication method thereof
CN109375240A (en) A kind of Low Altitude Target Detection system and method based on GNSS forward scattering characteristic

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
PE01 Entry into force of the registration of the contract for pledge of patent right
PE01 Entry into force of the registration of the contract for pledge of patent right

Denomination of invention: A VDES communication method using fast satellite search and onboard frequency offset processing

Effective date of registration: 20230724

Granted publication date: 20230414

Pledgee: China Construction Bank Corporation Weishan sub branch

Pledgor: Shandong Xingtong Easy Aviation Communication Technology Co.,Ltd.

Registration number: Y2023980049531