A method for determining satellite data operation mode in NB-s1 mode
The method addresses latency and congestion issues in satellite communication by initiating a 500-second timer and switching to store-and-forward mode if direct connection fails, enhancing reliability and efficiency in NB-S1 mode.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-07-30
- Publication Date
- 2026-03-19
AI Technical Summary
The existing timer method for satellite communication in NB-S1 mode introduces latency, leads to frequent attach procedure failures, high power consumption, and network congestion, especially in areas with poor satellite coverage or during handovers, due to the challenges of setting optimal timer values and managing store-and-forward operations.
A method that initiates a 500-second timer upon entering a satellite's footprint, switches to store-and-forward operation if connection is not established, and adjusts user equipment behavior to suspend processes relying on immediate data reception, ensuring efficient data transmission and reducing latency.
Reduces latency and power consumption, enhances reliability, and minimizes network congestion by dynamically switching between direct and store-and-forward modes based on network conditions, optimizing satellite communication efficiency.
Smart Images
Figure TR2025050833_19032026_PF_FP_ABST
Abstract
Description
[0001] DESCRIPTION
[0002] A METHOD FOR DETERMINING SATELLITE DATA OPERATION MODE IN NB-S1 MODE
[0003] TECHNICAL FIELD
[0004] Invention relates to a method for determining data operation type realized by a system comprising at least a satellite capable of transmitting data using store and forward (S&F) operation type or direct operation type wherein the satellite operates in Narrow Band Satellite S1 (NB-S1 ) mode, plurality of user equipment; plurality of ground stations for relaying transmission between user equipment and the satellite and a system thereof.
[0005] PRIOR ART
[0006] The store and forward method in satellite communication involves the satellite temporarily storing data before forwarding it to the ground station when a direct connection is not possible. This approach is particularly useful in scenarios where the satellite might not be in the direct line of sight of a ground station, leading to delays. This method is efficient for non-urgent data transmission, where the timing of delivery is flexible.
[0007] On the other hand, direct transmission allows for immediate data transfer from the user equipment (UE) through the satellite to the ground station, minimizing latency. However, it requires the satellite to be in a favorable position to establish a direct link with the ground station at the time of transmission.
[0008] In a satellite-based communication system, the attach procedure between a satellite and a base station involves establishing a connection between a user device (UE) and the terrestrial network via the satellite. The process begins with the UE sending an attach request, which the satellite relays to a ground station or gateway. This gateway then forwards the request to the base station or the relevant core network component. The network authenticates the user, sets up the necessary security measures, and then establishes the session, allowing the user device to connect to the network and begin communication. The satellite essentially acts as a bridge between the UE and the terrestrial network.
[0009] In the current 3GPP standards, particularly those related to Non-Terrestrial Networks (NTN), a "timer method" is employed to manage the attach procedure between a User Equipment (UE) and a satellite when using the store-and-forward technique. This technique is commonly used in satellite communication to address the inherent delays in satellite networks by allowing data to be stored at an intermediate point, such as the satellite itself, and forwarded to the ground station when communication is possible.
[0010] The timer method plays a crucial role in the attach procedure. When the UE initiates the attach process with the satellite, a timer is set to define the maximum allowable duration for completing this process, including the time required for storing and forwarding data. If the satellite cannot immediately communicate with the ground station due to coverage gaps or other reasons, the data is stored on the satellite. The timer ensures that the UE waits for a certain period until the satellite can forward the stored data to the ground station and complete the attach procedure.
[0011] However, if the timer expires before the attach procedure is completed, meaning the data has not been forwarded and the UE is not successfully attached, the procedure fails. In such cases, the UE might attempt to reinitiate the attach process or wait for a certain period before trying again.
[0012] This timer method has several shortcomings. One of the primary issues is the latency introduced by the store-and-forward method. If the timer is set too short, the attach procedure may fail frequently, leading to higher power consumption and reduced efficiency as the UE repeatedly tries to attach. Additionally, the method assumes that the satellite will eventually be in a position to forward the data to the ground station within the timer's limit. In regions with poor satellite coverage or during satellite handovers, this may not happen in time, causing the attach procedure to fail.
[0013] Another significant dranback is the resource consumption associated with repeated initiation of the attach procedure due to timer expiries. This not only affects the UE’s battery life but also increases the load on the satellite network. Moreover, determining the optimal timer value is challenging because it requires balancing latency and the probability of successful attachment. A timer that is too short may lead to frequent failures, while a timer that is too long could result in unnecessary delays in communication.
[0014] Finally, as the number of UEs increases, particularly in densely populated areas, the combination of the store-and-forward technique with the timer method may lead to congestion, further delaying communication and reducing the overall efficiency of the network. These issues highlight the need for more sophisticated methods to manage the attach procedure in satellite communications effectively.
[0015] All the problems mentioned above have made it necessary to make an innovation in the relevant technical field as a result.
[0016] BRIEF DESCRIPTION OF THE INVENTION
[0017] The present invention relates to a method to eliminate the above-mentioned disadvantages and bring new advantages to the relevant technical field.
[0018] An object of the invention is to reduce time spent on store and forward operations of user equipment in systems operate in NB-S1 mode.
[0019] To achieve all the objects mentioned above and that will emerge from the following detailed description, the present invention relates to a method is provided for determining data operation type realized by a system comprising at least a satellite capable of transmitting data using store and forward (S&F) operation type or direct operation type wherein the satellite operates in Narrow Band Satellite S1 (NB-S1 ) mode, plurality of user equipment; plurality of ground stations for relaying transmission between user equipment and the satellite. The method comprises initiating a timer when a source ground station falls within the satellite's footprint, the timer spanning a duration aligning with an expected time for completing Attach and Service Request procedures in NB-S1 mode. During the timer's progression, attempts by the satellite to establish a connection with a destination ground station are monitored. If the timer expires without successful connection establishment, the method switches to the store- and-forward (S&F) operation type and communicates the switch to the S&F operation type to the user equipment, enabling the user equipment to adjust its behavior by suspending ongoing processes that rely on immediate data reception. Thus, operations that use store forward can be cancelled if they are not completed within an expected time due to store and forward. This results in a time save for user equipment operations. This further increases reliability.
[0020] In accordance with other embodiments, the method further comprises adjusting, by the user equipment, its behavior in response to the communicated switch to the S&F operation type.
[0021] In yet other embodiments, the timer duration is 500 seconds. In accordance with further embodiments, the method further comprises transmitting data using the direct operation type if the connection is established before the timer expires.
[0022] In other embodiments, the method further comprises receiving, by the destination ground station, the transmitted data; sending, by the destination ground station, an acknowledgment back through the satellite to the source ground station within an acknowledgment time frame (in an another possible embodiment it is 500 seconds) of successful data receipt, confirming the success of the data transmission; and informing a user associated with the user equipment that the data transmission is completed using the direct operation type if the acknowledgment is received within a predetermined time.
[0023] In accordance with yet other embodiments, the method further comprises defining, by the user equipment, the data transmission as using the store-and-forward operation type if the acknowledgment is not received before the timer finishes.
[0024] In other embodiments, the method further comprises storing data in the satellite until a feeder link is available when using the S&F operation type and sending the stored data to the destination ground station when the feeder link becomes available.
[0025] In accordance with further embodiments, the user equipment receives notifications about the data operation type being used by the system.
[0026] In yet other embodiments, the satellite maintains a connection with the source and destination ground stations and manages data transmission based on network conditions and the timer.
[0027] BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Figure 1 is a drawing illustrating top schematic view of the system.
[0029] Figure 2 is a drawing illustrating a testing area of a simulation that the subject matter method is used.
[0030] REFERENCE NUMBERS GIVEN IN THE FIGURE
[0031] 100 Satellite
[0032] 110 Ground station 11 1 Source ground station
[0033] 112 Destination ground station
[0034] 120 User equipment
[0035] DETAILED DESCRIPTION OF THE INVENTION
[0036] In this detailed description, the subject matter is explained with references to examples without forming any restrictive effect only in order to make the subject more understandable.
[0037] The system described in figure 1 comprises a satellite (100) capable of transmitting data using either store and forward (S&F) operation type or direct operation type, operating in Narrow Band Satellite S1 mode (NB-S1 ) mode. The system comprises at least one ground station
[0038] (110) for relaying transmissions between user equipment (120) and the satellite (110). The satellite (100) maintains connectivity with both source ground stations (111 ) and destination ground stations (1 12), managing data transmission based on network conditions and an operational timer. The user equipment (120) receives notifications about the network’s operational mode, allowing it to adjust its operations accordingly.
[0039] Satellite (100) may be a LEO satellite.
[0040] The system realizes subject matter method. The initiation of the operation timer is a step in the subject matter method. In a possible embodiment, as soon as the source ground station
[0041] (11 1 ) falls within the satellite’s (100) footprint, a timer starts.
[0042] In a possible embodiment the timer spans 500 seconds, aligning with the expected time for completing the Attach and Service Request procedures in NB-S1 mode. The operation timer is defined by observing attach and service request procedure times for NB-S1 mode, which are given in Table 1. Subject matter method includes several steps that enhance the operational efficiency of satellite communications by using an operation timer and feedback mechanisms.
[0043] Table: 1 The satellite (100) maintains a connection with ground stations (1 10) and manages data transmission based on network conditions and the operational timer. The connectivity between the satellite (100) and the destination ground station (1 12) is established during the timer’s progression. If the connection is established before the timer expires, data is transmitted normally using direct mode, completing the operation with real-time communication.
[0044] If the timer expires without successful connection establishment, the operation is automatically switched to the store-and-forward (S&F) mode. This condition is then communicated back to the user equipment (120), which can adjust its behavior by suspending ongoing processes that rely on immediate data reception. The user equipment (120) is informed via a method about the S&F mode, which allows it to adjust its operations accordingly, possibly suspending or resuming certain processes. The processes rely on immediate data reception may for instance be navigation processes, machine learning processes and internet of things data transmission processes.
[0045] The satellite (100) maintains a connection with ground stations (1 10) and manages data transmission based on network conditions and the operational timer.
[0046] The satellite (100) facilitates data transmission using the S&F mode when direct transmission is infeasible. The process includes storing data in the satellite (100) until a feeder link is available when using the S&F operation type and sending the stored data to the destination ground station (1 12) when the feeder link becomes available. The satellite (100) maintains a connection with ground stations (110) and manages data transmission based on network conditions and the operational timer. The user equipment (120) receives notifications about the data operation type being used by the system, allowing it to adjust its operations based on network conditions.
[0047] If the successful connection establishment is realized before the expiration of the timer, the operation is realized in direct mode. Upon successful data receipt, the destination ground station (1 12) sends an acknowledgment back through the satellite (100) to the source ground station (11 1 ) within an acknowledgment time frame, confirming the success of the data transmission. Acknowledgment time frame may be 500 seconds. If this acknowledgment is received within 500 seconds, the user equipment (120) is informed that the operation is completed using real-time communication. However, if this acknowledgment is not received until the timer finishes, the user equipment (120) will define the operation as store and forward. NB-S1 mode refers to a Narrowband Signal mode in wireless communication systems, particularly relevant in scenarios where low data rates and power efficiency are prioritized, such as in loT (Internet of Things) applications. In NB-S1 mode, the system operates over a narrower bandwidth, which is advantageous for devices that transmit small amounts of data intermittently, like sensors or smart meters. This mode is optimized for conserving energy, extending battery life, and ensuring reliable communication over longer distances or in areas with poor signal coverage. By focusing on a narrow frequency band, NB-S1 mode minimizes interference and enhances the signal's robustness, making it ideal for use in environments where maintaining a stable connection is critical despite lower data transmission needs.
[0048] Table 2 comprises results of a simulation using subject matter method. A circular area is created. Inside of that area, we distributed circular areas that has an area of 3848 kilometer squared (ground station service area). The distribution is chosen as Poisson distribution.
[0049] At every trial choose the leftmost area and display it with a color (source ground station). Also one of the small circular areas that represents destination ground station (1 12) footprint areas are chosen randomly for every trial. Trial is an operation that checks network operation by using the scanning time of satellite for the distance between source and destination ground station (112).
[0050] Defined area is scanned from the leftmost point of the circle with 7.5 km / s speed (speed of the satellite). All the scanned areas will be in the service area of the satellite (100) since our defined areas are much smaller compared to the satellite footprint. When we scan the small circular areas they are noted as visited.
[0051] A timer which lasts 500 seconds (attach and service request time) starts when the any point of the leftmost small circular area is scanned. That area is considered as the source ground station (1 11 ) that starts the operation with the satellite. After the timer is finished, if any point of the randomly chosen area is scanned return that operation is completed without using S&F. Table shows time saved compared to using generic timer method.
[0052] Table 2
[0053] The scope of protection of the invention is specified in the attached claims and cannot be limited to those explained for sampling purposes in this detailed description. It is evident that a person skilled in the art may exhibit similar embodiments in light of the above-mentioned facts without drifting apart from the main theme of the invention.
Claims
CLAIMS1. A method for determining data operation type realized by a system comprising at least a satellite (100) capable of transmitting data using store and forward (S&F) operation type or direct operation type wherein the satellite (100) operates in Wide Band Satellite S1 (NB-S1 ) mode, plurality of user equipment (120); plurality of ground stations (110) for relaying transmission between user equipment (120) and the satellite (100) characterized in that- initiating a timer when a source ground station (11 1 ) falls within the satellite's (100) footprint, the timer spanning a duration aligning with an expected time for completing Attach and Service Request procedures in NB-S1 mode;- monitoring, during the timer's progression, attempts by the satellite (100) to establish a connection with a destination ground station (112); switching, if the timer expires without successful connection establishment, to the S&F operation type;- communicating the switch to the S&F operation type to the user equipment (120), enabling the user equipment (120) to adjust its behavior by suspending ongoing processes that rely on immediate data reception.
2. The method of claim 1 , characterized in that further comprising the step of adjusting, by the user equipment (120), its behavior in response to the communicated switch to the S&F operation type.
3. The method of claim 1 , wherein the timer duration is 500 seconds.
4. The method of claim 1 , characterized in that further comprising the step of transmitting data using the direct operation type if the connection is established before the timer expires.
5. The method of claim 4, characterized in that further comprising steps of:- receiving, by the destination ground station (1 12), the transmitted data;- sending, by the destination ground station (1 12), an acknowledgment back through the satellite (100) to the source ground station (1 1 1 ) within an acknowledgment time frame of successful data receipt, confirming the success of the data transmission; and- informing a user associated with the user equipment (120) that the data transmission is completed using the direct operation type if the acknowledgment is received within a predetermined time.
6. The method of claim 5, characterized in that further comprising step of defining, by the user equipment (120), the data transmission as using the store-and-forward operation type if the acknowledgment is not received before the timer finishes.
7. The method of claim 5 characterized in that the acknowledgment time frame is 500 seconds.
8. The method of claim 1 , characterized in that further comprising step of storing data in the satellite (100) until a feeder link is available when using the S&F operation type and sending the stored data to the destination ground station (112) when the feeder link becomes available.
9. The method of claim 1 , wherein the user equipment (120) receives notifications about the data operation type being used by the system.
10. The method of claim 1 , wherein the satellite (100) maintains a connection with the source and destination ground stations (1 12) and manages data transmission based on network conditions and the timer.
11. A system for determining data operation type comprising at least a satellite (100) capable of transmitting data using store and forward (S&F) operation type or direct operation type wherein the satellite (100) operates in Narrow Band Satellite S1 (NB- S1 ) mode, plurality of user equipment (120); plurality of ground stations (110) for relaying transmission between user equipment (120) and the satellite (100) characterized in that wherein the system is configured to realized one of the methods of one of the claims 1 -10.