A Computation Offloading Strategy in LEO Constellation Edge Cloud Network
Abstract
:1. Introduction
2. Related Works
3. System Model
3.1. Compute Offloading Mechanism
3.2. Communication Model
3.3. Network Model
3.4. Computation Model
4. Problem Formulation and Analysis
4.1. Energy Cost
4.1.1. Path Energy Cost
4.1.2. Computation Energy Cost
4.2. Computing Load Cost
4.3. Objective Function
5. Numerical Simulation
5.1. Simulation Setup
5.1.1. Constellation Parameter
5.1.2. User Task Parameter
5.1.3. Communication Parameter
5.2. Performance Metrics
5.3. Simulation Results
6. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
Abbreviations
LEO | Low Earth Orbit |
IoT | Internet of Thing |
LEO-ECN | LEO Constellation Edge Cloud Network |
5G | 5th Generation Mobile Networks |
6G | 6th Generation Mobile Networks |
VR/AR | Virtual Reality/Augmented Reality |
ADMM | Alternating Direction Method of Multipliers |
TDMA | Time Division Multiple Access |
MEC | Mobile Edge Computing |
CPU | Central Processing Unit |
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References | Offloading Scenario | Optimization Goal | Full Constellation Offload |
---|---|---|---|
[3] | - | - | mentioned |
[4] | multi-user single-satellite | user response time & user energy | no |
[5] | - | - | mentioned |
[6] | multi-user single-satellite | system energy & user delay | no |
[7] | multi-user multi-satellite | system energy & user delay | no |
[8] | multi-user multi-satellite | user energy | no |
[9] | multi-user one satellite orbit | - | mentioned |
Symbol | Definition |
---|---|
Set of LEO satellite m | |
Set of ground terminals | |
Set of computation task | |
Data size of task n | |
Number of CPU cycles for task n | |
Channel bandwidth of ground terminal n | |
Transmitting antenna gain of ground terminal n | |
Receiving antenna gain of ground terminal n | |
Rain attenuation of ground-satellite link | |
Free space loss of ground terminal n | |
Noise power of ground terminal to access satellite | |
Transmit power of ground terminal n | |
Inter-satellite link transmit rate from satellite i to j | |
Boltzmann’s constraint | |
System noise temperature | |
Ratio of received energy-per-bit to noise power density | |
Transmit power of satellite i to satellite j | |
Free space loss of the inter-satellite link | |
Graph of the k topology snapshots | |
V | Set of satellite nodes in the graph |
Set of inter-satellite links in the k snapshot | |
Maximum CPU cycles provided by onboard MEC server | |
Energy consumed on the path from ground terminal n to service satellite m | |
Energy that service satellite n consumes for task n | |
Number of hops ground terminal to service satellite | |
CPU frequency of the MEC server on the satellite m | |
The total cost of compute and path |
Parameter | Constellation 1 | Constellation 2 | Constellation 3 |
---|---|---|---|
constellation type | near-polar | near-polar | near-polar |
number of orbits | 6 | 6 | 12 |
satellites per orbit | 6 | 12 | 12 |
inclination | 86.4° | 86.4° | 86.4° |
semimajor axis | 7158.14 km | 7158.14 km | 7158.14 km |
altitude | 780 km | 780 km | 780 km |
longtitude boundary | 75° | 75° | 75° |
CPU frequency (Ghz) per MEC server | (1, 0.2) | (1, 0.2) | (1, 0.2) |
computation capacity per satellite (Gcycle/s) | (2, 0.2) | (2, 0.2) | (2, 0.2) |
Parameter | Value |
---|---|
Satellite terminal uplink power | 0.2 W |
Satellite terminal transmit rate | 2 Mbps |
Inter-satellite transmit power | 3 W |
Inter-satellite transmit rate | 30 Mbps |
Boltzmann’s constraint | 228.6 dB |
System noise temperature | 25 dB |
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Dong, F.; Huang, T.; Zhang, Y.; Sun, C.; Li, C. A Computation Offloading Strategy in LEO Constellation Edge Cloud Network. Electronics 2022, 11, 2024. https://doi.org/10.3390/electronics11132024
Dong F, Huang T, Zhang Y, Sun C, Li C. A Computation Offloading Strategy in LEO Constellation Edge Cloud Network. Electronics. 2022; 11(13):2024. https://doi.org/10.3390/electronics11132024
Chicago/Turabian StyleDong, Feihu, Tao Huang, Yasheng Zhang, Chenhua Sun, and Chengcheng Li. 2022. "A Computation Offloading Strategy in LEO Constellation Edge Cloud Network" Electronics 11, no. 13: 2024. https://doi.org/10.3390/electronics11132024
APA StyleDong, F., Huang, T., Zhang, Y., Sun, C., & Li, C. (2022). A Computation Offloading Strategy in LEO Constellation Edge Cloud Network. Electronics, 11(13), 2024. https://doi.org/10.3390/electronics11132024