Dynamic Separation Angle Threshold for Satellite Interference Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The coexistence of non-geostationary and geostationary satellite communications systems in shared frequency bands poses challenges in managing interference, leading to reduced geographical coverage and increased costs due to the need for high separation angles and additional satellites to maintain regulatory interference levels, especially in high-frequency bands like Ka band.
Innovation Solution
A dynamic radio resource allocation method that adjusts the separation angle threshold for each terminal based on the overall level of interference generated towards geostationary systems, iteratively calculating and optimizing the separation angle to ensure compliance with regulatory limits while maximizing geographical coverage and minimizing the number of satellites.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a fixed high separation angle threshold is used to ensure regulatory compliance, then interference levels towards geostationary systems are controlled, but geographical coverage is reduced
Solution Approach 1:
The patent applies dynamics by transitioning from a fixed separation angle threshold to a dynamic threshold that adapts based on real-time system conditions. The control device continuously monitors the actual interference level and adjusts the separation angle threshold accordingly, allowing the system to maintain regulatory compliance while optimizing geographical coverage as conditions change.
Solution Approach 2:
The patent implements parameter changes by modifying the separation angle threshold parameter based on measured interference levels. When actual interference is below the reference level, the threshold is reduced to expand coverage; when interference approaches limits, the threshold is increased to maintain compliance. This dynamic parameter adjustment resolves the contradiction between coverage and interference control.
2Area of stationary object
If the number of non-geostationary satellites is increased to maintain coverage with separation constraints, then geographical coverage is ensured, but system costs increase
Solution Approach 1:
The patent employs feedback mechanisms where the control device continuously monitors actual interference levels and uses this information to dynamically adjust separation angle thresholds. This feedback loop allows the system to maintain coverage with fewer satellites by optimizing the use of available satellites through adaptive threshold adjustment rather than relying on static over-provisioning.
Solution Approach 2:
By dynamically changing the separation angle threshold parameter based on actual interference measurements, the system can maximize the utilization of each satellite's coverage area. This reduces the need for additional satellites to compensate for conservative fixed thresholds, thereby lowering system costs while maintaining coverage.
3Object-affected harmful factors
If a static separation method is used for low frequency bands, then interference avoidance is achieved, but it becomes inadequate for high frequency bands with atmospheric attenuation
Solution Approach 1:
The patent transitions from static separation methods to dynamic interference management that adapts to different frequency bands and atmospheric conditions. The control device continuously measures actual interference levels and adjusts separation thresholds in real-time, making the system versatile across frequency bands including high-frequency Ka band where atmospheric attenuation varies dynamically.
Solution Approach 2:
The system changes the separation angle threshold parameter dynamically based on measured interference conditions rather than using fixed static values. This allows the same system to effectively operate across different frequency bands (Ku, Ka, etc.) by adapting the threshold to actual atmospheric and interference conditions, resolving the lack of frequency band adaptability.
4Area of stationary object
If high transmission powers are used to maintain coverage at low elevation angles, then coverage capability is improved, but interference with geostationary systems increases
Solution Approach 1:
The control device uses feedback from actual interference measurements to dynamically adjust separation angle thresholds. When high transmission powers are needed for low elevation angle coverage, the system monitors the resulting interference and adjusts thresholds to maintain compliance, allowing high power operation only when interference levels permit.
Solution Approach 2:
The system dynamically changes the separation angle threshold parameter in response to transmission power levels and resulting interference. This allows the system to optimize coverage capability through high power transmission when conditions allow, while automatically adjusting thresholds to prevent excessive interference, resolving the contradiction between coverage and interference generation.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
Method for allocating radio resources for establishing satellite communications in a first communications system comprising a low-Earth orbital satellite constellation (SAT_NGS01, SAT_NGS02) and a first set of terminals (TER_NGS01, TER_NGS02), the method comprising the following steps, for each terminal (TER_NGS01, TER_NGS02) of the first set: - determine a distinct separation angle threshold to be respected with respect to a geostationary satellite constellation (SAT_GSO), a separation angle being defined as the smallest topocentric angle subtended by a given low-Earth orbital satellite (SAT_NGS01, SAT_NGS02) and any geostationary satellite (SAT_GSO) in the geostationary arc being seen from a given terminal (TER_NGSO1, TER_NGSO2) of the first set, - allow the terminal (TER_NGSO1, TER_NGSO2) to establish a communication link with a low-Earth orbital satellite (SAT_NGSO1,SAT_NGSO2) if the separation angle (αt11,at22) associated with said connection is greater than or equal to the separation angle threshold.