Organizations: Department of Computer Science, University of Massachusetts, Boston, Boston, MA, 02125, USA · Graduate School of Informatics, Osaka Metropolitan University, Osaka, Japan
This paper considers reliable in-sequence molecular communication, where bio-nanomachines exchange molecule-encoded information in a specified order, and investigates a new simulation-based method to incrementally evaluate communication protocols by gradually increasing the complexity of experimental settings. The proposed method, called Affine Memory Replay (AMR), builds a continual learning (CL) model to estimate communication performance between bio-nanomachines. AMR stores past simulation samples and synthesizes additional replay samples through interpolation and extrapolation between past samples. Through incremental performance estimation tasks, it replays both past and synthetic samples to regularize model updates, helping the model adapt to new experimental settings while retaining knowledge from earlier ones. Experimental results show that AMR significantly outperforms existing CL methods in maintaining overall estimation accuracy across sequentially learned estimation tasks. It effectively balances memory stability and learning plasticity under moderate training cost.
Figures & tables
Fig. 1: Diffusive, Directional and Hybrid Transports with SW-ARQ in Molecular Communication
Fig. 2: Interaction between the Tx and the Rx
Method
Parameter
Value
Method
Parameter
Value
AMR
α
1
CLeaR
α
0.5
β
0.5
λ
2
Primary buffer size
50
Buffer size
50
Secondary buffer size
50
Synthesis range param q
0.1
ACLT
α
0.2
A2ER
α
1
TABLE I: Hyperparameter configuration
Parameter
Value
Size length of the environment
150 μ m
Diameter of Tx and Rx
5 μ m
Tx to Rx distance
10 to 90 μ m
Diameter of an information/ACK molecule
1 μ m
Diameter of a noise molecule
1 μ m
Number of noise molecules
0 to 10 5
TABLE II: Simulation Settings for Molecular Communication
Fig. 3: RTT Estimation Tasks (T1 to T12)
Method
Lplasticity
Lstability
F
AMR
0.1069 ± 0.0112
0.1399 ± 0.0101
0.0330 ± 0.0138
ACLT
0.1073 ± 0.0116
0.1457 ± 0.0157 *!
0.0384 ± 0.0182
A2ER
0.1057 ± 0.0127
0.1463 ± 0.0158 *!
0.0406 ± 0.0173 *!
CLeaR
0.1075 ± 0.0115
0.1454 ± 0.0131 *!
0.0379 ± 0.0152
TABLE III: RTT Estimation Performance
Fig. 4: Change of forgetting ratio as the number of sequential tasks varies
Method
Total Training Time (sec)
Per-task Time (sec)
AMR
8.76 ± 1.50
0.73
ACLT
11.64 ± 1.02
0.97
A2ER
8.20 ± 1.07
0.68
CLeaR
7.39 ± 0.86
0.62
TABLE IV: Computational cost for training
Fig. 5: Tradeoff between Estimation Performance and Training Cost
q
Lplasticity
Lstability
F
0.0
0.1053 ± 0.0090
0.1408 ± 0.0120
0.0355 ± 0.0155
0.05
0.1079 ± 0.0105
0.1415 ± 0.0080
0.0335 ± 0.0123
0.1
0.1069 ± 0.0113
0.1399 ± 0.0101
0.0330 ± 0.0138
0.2
0.1097 ± 0.0106
0.1405 ± 0.0105
0.0308 ± 0.0128
0.3
0.1076 ± 0.0115
0.1412 ± 0.0120
0.0336 ± 0.0162
1.5
0.1060 ± 0.0124
0.1416 ± 0.0126
0.0356 ± 0.0150
TABLE V: RTT Estimation Performance (AMR)
Fig. 6: Change in forgetting ratio as the number of tasks varies (AMR)
q
Total Training Time (sec)
Per-task Time (sec)
0.0
9.46 ± 1.73
0.79
0.05
10.29 ± 1.99
0.86
0.1
8.76 ± 1.50
0.73
0.2
8.80 ± 1.51
0.73
0.3
9.10 ± 1.71
0.76
1.5
10.04 ± 1.19
0.84
TABLE VI: Computational Cost for Training (AMR)
Fig. 7: Tradeoff between Estimation Performance and Training Cost (AMR)
Department of Computer Science, University of Massachusetts, Boston Boston, MA, 02125, USA · Graduate School of Informatics, Osaka Metropolitan University Osaka, Japan