2024. 5. 20. 06:35ㆍ카테고리 없음
Introduction
Military satellite communication networks are crucial for providing stable data transmission by overcoming geographical limitations. Currently, the Korean military operates a satellite communication network through the Mugunghwa 5 satellite, launched in 2007, and is preparing for the next-generation military satellite communication system aimed to be operational by 2017. The next-generation military satellite communication system aims to provide three times the relay capacity of the existing system, expand communication coverage, and enhance communication survivability. Efficient use of limited wireless resources is essential to achieve these goals.
Overview of MF-TDMA Technology
MF-TDMA (Multi Frequency-Time Division Multiple Access) is a technology that dynamically operates frequency and time resources simultaneously. It combines the advantages of FDMA and TDMA by dividing the wireless resources into time and frequency segments, allowing efficient use of limited resources. The resource allocation performance of MF-TDMA is determined by the method of wireless resource allocation for each ground terminal.
Resource Allocation Techniques
In this study, we propose an efficient MF-TDMA resource allocation technique for the next-generation military satellite communication system and compare its performance with existing resource allocation methods. The analysis includes Total Resource Efficiency, Reject Ratio, Computational Time, and Power Spectral Density (PSD) distribution to evaluate the efficiency of wireless resource usage, probability of resource allocation failure, required time, and channel interference.
Existing Resource Allocation Techniques
- First Fit: Allocates resources by searching from the baseline frequency band and assigning resources immediately if available.
- Best Fit: Searches the allocation information of all frequency bands and selects the band with the least remaining resources among the available candidate bands.
- RCP Fit: Considers ground terminal information and sets specific ground terminal reservation bands for each frequency band, ensuring resources from the same terminal are allocated to the same band.
- Power Control-Based Resource Allocation Technique: Considers the characteristics of heterogeneous terminals and calculates the frequency-time structure of Burst and PSD values for each structure, combining them according to resource size.
Proposed Resource Allocation Technique
The proposed resource allocation technique includes the following steps:
- Calculate the size of the required Burst using the amount of data to be transmitted and the amount of data transmittable per slot.
- Set the structure of Burst using the maximum bandwidth based on the calculated Burst size.
- Reconfigure the structure if the number of frequency slots exceeds the average Burst size.
- Set the order of resource allocation.
- Allocate resources within the MF-TDMA frame according to the set order.
Performance Comparison
To compare the performance of the proposed resource allocation technique with existing methods, we constructed a system environment considering the next-generation military satellite communication system. The comparison includes the following metrics:
- Total Resource Efficiency: Indicates the amount of actual allocated resources compared to the total MF-TDMA frame resources.
- Reject Ratio: Represents the percentage of Burst that failed to allocate resources out of the total Burst.
- Computational Time: Measures the time required for each resource allocation process through simulation, analyzing the complexity of each technique.
- PSD Distribution: Measures the PSD distribution across frequency bands to compare channel interference.
Result Analysis
- Total Resource Efficiency: First fit and Best fit showed similar resource usage efficiency, while RCP fit, power control-based allocation, and the proposed technique showed increasing efficiency.
- Reject Ratio: First fit and Best fit had higher failure probabilities, while RCP fit, power control-based allocation, and the proposed technique showed decreasing failure probabilities.
- Computational Time: Best fit required more time than First fit. RCP fit took less time due to predefined frequency bands, while power control-based allocation and the proposed technique showed the most efficient performance.
- PSD Distribution: The uniform bandwidth allocation techniques had large PSD variations, while the power control-based and proposed techniques showed more even PSD distribution, indicating better channel interference management.
Conclusion
This study proposed an efficient MF-TDMA resource allocation technique for the next-generation military satellite communication system and compared its performance with existing methods. The proposed technique showed superior performance in Total Resource Efficiency and Reject Ratio, and improved Computational Time compared to existing methods. The proposed technique also demonstrated better PSD distribution, indicating reduced channel interference.
Further research on efficient resource allocation techniques in various environments is expected to contribute to the efficient use of limited wireless resources and improved communication performance in next-generation military satellite communication systems.
References
- ITU, Handbook on Satellite Communications, 3rd ed., Wiley-Interscience, 2002.
- Soon Woo et al., “A Power Control-Based MF-TDMA Resource Allocation Scheme for Next Generation Military Satellite Communication Systems”, The Korean Institute of Communications and Information Sciences(KICS), 2012.
- S. W. Han and J. W. Seo, “Future extension of the next generation military satellite”, Information and Communications Magazine, 2009.
- Hong-jun Noh et al., “Resource Allocation and IP Networking for Next Generation Military Satellite Communications System”, The Korean Institute of Communications and Information Sciences(KICS), 2013.
- Jung-Min Park et al., “Allocation of QoS Connections in MF-TDMA Satellite Systems: A Two-Phase Approach”, IEEE Transactions on Vehicular Technology, 2005.
- Dongdong Qiu et al., “A Novel Resource Allocation Scheme Based on Multi-satellite Terminals in MF-TDMA Satellite Systems”, 2013 6th International Congress on Image and Signal Processing(CISP), 2013.
- Pan Xiaofei and Wei Li, “Resource Allocation in Variable Bandwidth MF-TDMA Satellite Communications”, 2006 8th International Conference on Signal Processing, 2006.
- Qijia Dong et al., “Optimal Timeslot Allocation Algorithm in MF-TDMA”, 2008 4th International Conference on Wireless Communications, Networking and Mobile Computing, 2008.