Dynamic access method for low earth orbit satellites in VDES system

A low-orbit satellite and dynamic access technology, applied in the transmission system, radio transmission system, electrical components, etc., can solve the problem of not being able to make full use of idle channel resources, effectively reducing Doppler frequency shift, and not considering access sequencing, etc. problem, achieve the effect of reducing Doppler frequency shift, improving success rate, and ensuring timeliness

Active Publication Date: 2021-11-16
山东星通易航通信科技有限公司
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This direct competition access method gives up the access when the ship's minimum Doppler frequency shift low-orbit satellite has no free channels, and does not consider the dynamic adjustment of the ship's access within the coverage of multiple low-orbit satellites, so it cannot fully Utilize idle channel resources, and the direct contention access method does not consider the access sequence according to the Doppler frequency shift value, so the Doppler frequency shift of the system cannot be effectively reduced

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Dynamic access method for low earth orbit satellites in VDES system
  • Dynamic access method for low earth orbit satellites in VDES system
  • Dynamic access method for low earth orbit satellites in VDES system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] Such as Figure 1~3 Shown, the dynamic access method of the low-orbit satellite in a kind of VDES system disclosed by the present invention, comprises the following steps:

[0037] Step 1: Sort and number ships according to the Doppler shift of the uplink signal

[0038] There are N ships, such as figure 2 , where each ship is located at least φ 1 and φ 2 Within the coverage of one of the two low-orbit satellites, and the N ships simultaneously send uplink access request signals, the low-orbit satellite φ 1 and φ 2 Estimate the Doppler frequency shift of the uplink signal of each ship separately, where the ith ship is relative to the LEO satellite φ 1 and φ2 The Doppler frequency shift of the uplink signal is denoted as with where i ∈ {1, 2, ..., N};

[0039] If the i-th ship is only on the LEO satellite φ 1 or φ 2 within the coverage of or

[0040] First find out the φ of each ship relative to the low-orbit satellite 1 and φ 2 The minimum and maximu...

Embodiment 2

[0057] Embodiment 2 (experimental example)

[0058] The following is a simulation experiment carried out according to a dynamic access method of a low-orbit satellite in a VDES system disclosed by the present invention, to illustrate the feasibility and effectiveness of the method of the present invention.

[0059] During the simulation, the radius of the earth is set to 6370km, the orbit height of the two low-orbit satellites is 780km, the frequency of the uplink signal is 160MHz, and 10 consecutive minutes are selected as the simulation time. The total number of idle channels of the two low-orbit satellites is 100, and the idle channel Randomly distributed on the two low-orbit satellites, the ships obey the uniform distribution within the coverage of the two low-orbit satellites. In the simulation, if the ship fails to connect successfully, it will be calculated according to the maximum Doppler frequency shift of 40KHz.

[0060] Figure 4 It is a simulation result diagram,...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention belongs to the technical field of wireless communication, and particularly relates to a dynamic access method of a low-orbit satellite in a VDES system, which comprises the following steps of: sequencing and numbering ships according to Doppler frequency shift of uplink signals; and according to the serial numbers of the ships, performing uplink dynamic access of the low-orbit satellites on the ships in sequence. Compared with an existing direct competition access method, the method has the advantages that the ships are sequenced according to the Doppler frequency shift values, and the ships with small Doppler frequency shift values are accessed according to the sequence, so that the Doppler frequency shift of the system can be reduced; according to the invention, when the ship is in the coverage range of a plurality of low-earth-orbit satellites, dynamic adjustment that one low-earth-orbit satellite is adjusted to another low-earth-orbit satellite for access when the access of the low-earth-orbit satellite fails is added, so that idle channel resources of the low-earth-orbit satellites can be fully utilized. Therefore, according to the method disclosed by the invention, idle channel resources of the low-orbit satellite can be fully utilized, and the Doppler frequency shift of the system is effectively reduced.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, and in particular relates to a dynamic access method of a low-orbit satellite in a VDES system. Background technique [0002] Maritime communication is the need for ships to sail at sea, and it is also the need to ensure the safety of ships. The original maritime communication mainly relies on the automatic identification system (Automatic Identification System, AIS) to realize the information transmission between ships, coasts and satellites. With the increasing number of ships and the diversification of information needs, ships, coasts and satellites need stronger data exchange capabilities to exchange richer information, such as navigation, collision avoidance, meteorology, hydrology, risk warning, search and rescue information etc. The original AIS system can no longer meet the actual needs, so the International Association of Lighthouse Authorities (IALA) proposed the VHF Da...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): H04B7/185
CPCH04B7/18519Y02D30/70
Inventor 李洪星丁晓光
Owner 山东星通易航通信科技有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap