KR-20260067330-A - METHOD AND APPARATUS FOR DETERMINING A ROUTING PATH

KR20260067330AKR 20260067330 AKR20260067330 AKR 20260067330AKR-20260067330-A

Abstract

The method of the first communication node includes the steps of receiving data from the second communication node through a ground relaying (GR) method, determining the number of hops, the up elevation angle, and the down elevation angle such that the propagation delay time through the GR method is smaller than the propagation delay time through a ground path, determining the third communication node based on the up elevation angle and the down elevation angle, and transmitting data to the third communication node through the GR method.

Inventors

박주한
황유선
강숙양
배명산
배형득
신재승
신재욱
엄차현
오성민
정광렬

Assignees

한국전자통신연구원

Dates

Publication Date: 20260512
Application Date: 20251030
Priority Date: 20241105

Claims (12)

As a method of the first communication node, A step of receiving data from a second communication node via a GR (ground relaying) method; A step of determining the number of hops, the upward elevation angle, and the downward elevation angle so that the propagation delay time through the above GR method is smaller than the propagation delay time through the ground path; A step of determining a third communication node based on the above upward elevation angle and the above downward elevation angle; and A step comprising transmitting the data to the third communication node via the GR method, Method of the first communication node.
In claim 1, The above data includes at least one of the latitude of the second communication node, the longitude of the second communication node, the latitude of the transmission end node from which the data originated, the longitude of the transmission end node, the latitude of the receiving end node where the data arrives, or the longitude of the receiving end node. Method of the first communication node.
In claim 1, The step of determining the above hop number, the above upward elevation angle, and the above downward elevation angle is, A step of determining a plurality of hop counts such that a first critical function included in a first inequality defining a lower limit of the upward elevation angle is not higher than a second critical function included in a second inequality defining an upper limit of the upward elevation angle; A step of determining upward elevation angle-downward elevation angle pairs corresponding to each of the plurality of hop counts using the second threshold function; A step of determining a diagonal distance corresponding to each of the above-mentioned upward elevation angle-downward elevation angle pairs; and A step comprising determining an upward elevation angle-downward elevation angle pair corresponding to the smallest diagonal distance among the upward elevation angle-downward elevation angle pairs based on the diagonal distances, Method of the first communication node.
In claim 3, The above first inequality defines an upward elevation angle such that the propagation delay time through the GR method is smaller than the propagation delay time through the ground path, Method of the first communication node.
In claim 3, The second inequality and the third inequality define an upward elevation angle that causes the data to be transmitted to the receiving end node through the number of hops included in the first threshold function, Method of the first communication node.
In claim 2, The step of determining the third communication node above is, A step of determining a direction vector from the first communication node to the receiving end node based on at least one of the latitude of the first communication node, the longitude of the first communication node, the latitude of the receiving end node, or the longitude of the receiving end node; A step of determining a first latitude and a first longitude based on at least one of the above direction vector or the above upward elevation angle and the above downward elevation angle and the ground advance distance corresponding to them; and A step comprising determining the communication node closest to the location corresponding to the first latitude and the first longitude as the third communication node. Method of the first communication node.
As the first communication node, It includes at least one processor, and The above at least one processor is the first communication node, Receive data from the second communication node via the GR (ground relaying) method; Determine the number of hops, the upward elevation angle, and the downward elevation angle so that the propagation delay time through the above GR method is smaller than the propagation delay time through the ground path; Determining a third communication node based on the above upward elevation angle and the above downward elevation angle; and Causing the above third communication node to transmit the above data through the above GR method, 1st communication node.
In claim 7, The above data includes at least one of the latitude of the second communication node, the longitude of the second communication node, the latitude of the transmission end node from which the data originated, the longitude of the transmission end node, the latitude of the receiving end node where the data arrives, or the longitude of the receiving end node. 1st communication node.
In claim 7, When the first communication node determines the hop count, the upward elevation angle, and the downward elevation angle, the at least one processor, the first communication node, Determining a plurality of hops such that the first critical function included in the first inequality defining the lower limit of the upward elevation angle is not higher than the second critical function included in the second inequality defining the upper limit of the upward elevation angle; Determining upward elevation angle-downward elevation angle pairs corresponding to each of the above plurality of hop counts using the above second threshold function; Determine the diagonal distance corresponding to each of the above upward elevation angle-downward elevation angle pairs; and Causing to determine the upward elevation angle-downward elevation angle pair corresponding to the smallest diagonal distance among the upward elevation angle-downward elevation angle pairs based on the above diagonal distance, 1st communication node.
In claim 9, The above first inequality defines an upward elevation angle such that the propagation delay time through the GR method is smaller than the propagation delay time through the ground path, 1st communication node.
In claim 9, The second inequality and the third inequality define an upward elevation angle that causes the data to be transmitted to the receiving end node through the number of hops included in the first threshold function, 1st communication node.
In claim 8, When the first communication node determines the third communication node, the at least one processor determines that the first communication node, Determining a direction vector from the first communication node to the receiving end node based on at least one of the latitude of the first communication node, the longitude of the first communication node, the latitude of the receiving end node, or the longitude of the receiving end node; Determining a first latitude and a first longitude based on at least one of the above direction vector or the ground advance distance corresponding to the above upward elevation angle and the above downward elevation angle; and Causing the communication node closest to the location corresponding to the first latitude and the first longitude to be determined as the third communication node, 1st communication node.

Description

Method and apparatus for determining a routing path The present invention relates to an improved communication technology, and more specifically, to a technology for determining routing paths between satellites in a non-terrestrial network. Communication networks (e.g., 5G communication networks, 6G communication networks, etc.) are being developed to provide communication services that are improved over existing communication networks (e.g., LTE (long term evolution), LTEA (advanced), etc.). 5G communication networks (e.g., NR (new radio) communication networks) can support frequency bands above 6 GHz as well as frequency bands below 6 GHz. In other words, 5G communication networks can support the FR1 band and/or FR2 band. 5G communication networks can support a wider variety of communication services and scenarios compared to LTE communication networks. For example, usage scenarios for 5G communication networks may include eMBB (enhanced Mobile BroadBand), URLLC (Ultra Reliable Low Latency Communication), mMTC (massive Machine Type Communication), etc. Inter-satellite links (ISLs) can be formed between satellites in a non-terrestrial network (NTN). The NTN can provide services to enable communication between two users located on the ground via the ISL. Satellites can provide services using the store and forward (S&F) method. The S&F method can be as follows: A satellite can receive data from a user or another satellite. The satellite can store the received data. The satellite can move on the ground. The moved satellite can transmit the stored data to the user or another satellite. When communication between two ground-based nodes is performed via the S&F method, the following problems may arise. First, the satellite stores the received data and can only process it once a connection is established between the satellite and the ground node. Consequently, latency may increase. Second, if the satellite is a low-orbit satellite, there may be limitations to its computational capabilities. However, when communication is performed via the S&F method, the low-orbit satellite must process a large amount of data within a limited timeframe. Therefore, the S&F method can cause a computational load on the low-orbit satellite. To address the aforementioned issues, a method that minimizes latency may be required for data transmission between geographically distant users. FIG. 1 is a conceptual diagram illustrating embodiments of a non-ground network. FIG. 2 is a conceptual diagram illustrating embodiments of a non-ground network. FIG. 3 is a block diagram illustrating embodiments of entities constituting a non-terrestrial network. Figure 4 is a conceptual diagram illustrating embodiments of a data transmission procedure through the S&F (store and forward) method. Figure 5 is a graph showing the average propagation delay time according to the maximum allowable relative angular velocity. Figure 6 is a graph showing the number of connectable satellites over time. Figure 7 is a conceptual diagram illustrating the elements constituting a GR (ground relaying) hop. Figure 8a is a graph showing the distribution of conditions used to determine end-to-end routing paths. Figure 8b is a graph showing the distribution of conditions used to determine end-to-end routing paths. Figure 8c is a graph showing the distribution of conditions used to determine end-to-end routing paths. Figure 8d is a graph showing the distribution of conditions used to determine end-to-end routing paths. FIG. 9a may be pseudocode containing an algorithm used to determine an end-to-end routing path. Figure 9b may be pseudocode containing an algorithm used to determine an end-to-end routing path. Figure 10a is a graph showing the optimal upward elevation angle and the optimal number of GR (ground relaying) hops according to the great circle distance. Figure 10b is a graph showing the end-to-end delay time according to the great distance. FIG. 11 is a flowchart illustrating embodiments of the GR routing path determination procedure. The present disclosure is capable of various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present disclosure to specific embodiments, and it should be understood that it includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the present disclosure. Terms such as "first," "second," etc., may be used to describe various components, but said components should not be limited by said terms. Such terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present disclosure, the first component may be named the second component, and similarly, the second component may be named the first component. The term "and/or" includes a combination of a plurality of related described items or any of a plu