GEO-LEO satellite network for global information distribution

Abstract

The invention discloses a GEO-LEO satellite network for global information distribution. The GEO-LEO satellite network comprises an outer-layer backbone network composed of three GEO satellites and an inner-layer enhanced network composed of at least one LEO satellite, the three GEO satellites are located over the terrestrial equator, the fixed point longitude difference is 120 degrees, the GEO satellites are connected through fixed inter-satellite links, the height of an LEO satellite orbit is 1,450 km, the orbit inclination is 84.5 degrees, the outer-layer backbone network and the inner-layer enhanced network carry out information distribution in a broadcast mode, the outer-layer backbone network and the inner-layer enhanced network carry out broadcast in a rate-free coding mode, and the GEO-LEO satellite network and the ground carry out broadcast in a rate-free coding mode. According to the GEO-LEO satellite network, seamless and enhanced coverage on the middle and low latitudes can be achieved only through few satellites, meanwhile, coverage on the south and north polar regions is considered, and worldwide interruption-tolerant distribution of information is achieved.

Description

technical field [0001] The invention belongs to the technical field of satellite communication, in particular to a double-layer satellite network which realizes content interruption and distribution of information in a global scope. Background technique [0002] In recent years, with the increasing demand for satellite communications in commercial and military fields, satellite communications have begun to develop from a single-layer satellite network to a multi-layer satellite network. The single-layer satellite constellation is mainly divided into GEO (Geostationary Earth Orbit, geosynchronous orbit satellite) constellation, MEO (Medium Earth Orbit, medium orbit satellite) constellation and LEO (Low Earth Orbit, low orbit satellite) constellation. GEO constellation usually only needs 3 GEO satellites to cover the middle and low latitude regions of the world continuously, with less coverage switching and low economic cost of construction, but the system cannot cover the who...

AI Technical Summary

Problems solved by technology

However, these multi-layer satellite networks use many LEO satellites or MEO satellites to realize global information transmission. For example, Kimmura’s design uses 588 LEO satellites, Lee and Akyildiz use 72 LEO satellites, and Hu Jianhao uses 63 LEO satellites, and inter-satellite links are established between most satellites, link switching is relatively frequent, the design requirements for satellites are high, and the cost of the entire satellite network is relatively high

[0004] At the same time, in satellite communication, due to the interference of harsh conditions such as atmospheric attenuation and electromagnetic radiation, the channel bit error rate may deteriorate sharply, the success rate of a single data transmission is low, and the propagation delay of satellite links is large, so the strategy of feedback retransmission It will cause greater delay. Forward error correction codes represented by convolutional codes, Turbo codes, and LDPC codes are generally only used to detect and correct smaller blocks of data. In addition, inter-satellite links in satellite communications are prone to interruption. And the characteristics of frequent switching between LEO satellites and the ground

[0005] To sum up, due to the advantages and disadvantages of the single-layer satellite network of LEO, MEO and GEO in the communication process, it is difficult to adapt to the growing demand for integrated services. Information distribution requires a lot of LEO satellites or MEO satellites, and satellites in different layers are mostly interconnected through inter-satellite links. The requirements for the on-board processing capacity of LEO satellites are relatively high, and the cost of the entire satellite network is too high

[0006] Therefore, the problem existing in the existing technology is: how to realize fast and reliable information distribution on a global scale with only a small number of satellites and a relatively simple satellite network topology

Images