WaveComm: Lightweight Communication for Collaborative Perception via Wavelet Feature Distillation
Authors: Erdemt Bao, Jin Yang
Organizations: School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China. · National Key Laboratory of Human-Machine Hybrid Augmented Intelligence, and Institute of Artificial Intelligence and Robotics, Xi’an Jiaotong University, Shaanxi 710049, China.
In multi-agent collaborative sensing systems, substantial communication overhead from information exchange significantly limits scalability and real-time performance, especially in bandwidth-constrained environments. This often results in degraded performance and reduced reliability. To address this challenge, we propose WaveComm, a wavelet-based communication framework that drastically reduces transmission loads while preserving sensing performance in low-bandwidth scenarios. The core innovation of WaveComm lies in decomposing feature maps using Discrete Wavelet Transform (DWT), transmitting only compact low-frequency components to minimize communication overhead. High-frequency details are omitted, and their effects are reconstructed at the receiver side using a lightweight generator. A Multi-Scale Distillation (MSD) Loss is employed to optimize the reconstruction quality across pixel, structural, semantic, and distributional levels. Experiments on the OPV2V and DAIR-V2X datasets for LiDAR-based and camera-based perception tasks demonstrate that WaveComm maintains state-of-the-art performance even when the communication volume is reduced to 86.3% and 87.0% of the original, respectively. Compared to existing approaches, WaveComm achieves competitive improvements in both communication efficiency and perception accuracy. Ablation studies further validate the effectiveness of its key components.
Figures & tables
Fig. 1: Feature transmission methods in collaborative perception. (a) Spatial domain methods: The sender vehicle encodes data, applies compression or selection, and transmits it to the receiver vehicle, which performs feature fusion and decoding. (b) Frequency domain methods: The sender encodes data into low- and high-frequency components, primarily transmitting low-frequency data. The receiver reconstructs the original features from these components, followed by feature fusion and decoding.
Fig. 2: Overview of WaveComm. WaveComm enables efficient information exchange among intelligent agents to support collaborative autonomous driving. (a) BEV Feature Encoder, which converts agent observations into BEV feature maps. (b) Wavelet Feature Distillation, which employs DWT to decompose features into low- and high-frequency components, followed by a Wavelet Generator and Wavelet Discriminator for efficient feature reconstruction using IDWT. (c) Feature Fusion, which integrates features from multiple agents to enhance the overall feature representation effectively. (d) Detection Head, which produces final detection outputs based on the fused features.
Fig. 3: Architecture of Wavelet Generator and Wavelet Discriminator. The Wavelet Generator uses Decoder, Upsample, and Output modules to reconstructed features Z^i from the transmitted low-frequency component. The Wavelet Discriminator employs Sigmoid to generate a probability map P like PatchGAN [ 33 ] .
Dataset
OPV2V
DAIR-V2X
Method
Camera-based
LiDAR-based
Camera-based
LiDAR-based
AP50 ↑
AP70 ↑
Comm
AP50 ↑
AP70 ↑
Comm
AP30 ↑
AP50 ↑
Comm
AP30 ↑
AP50 ↑
Comm
No Collaboration
0.405
0.216
0.0
0.782
0.634
0.0
0.014
0.004
0.0
0.421
0.405
0.0
F-Cooper (2019)
0.469
0.219
22.0
0.763
0.481
24.0
0.115
0.026
23.0
0.723
0.620
23.0
DiscoNet (2021)
0.517
0.234
22.0
0.882
0.737
24.0
0.083
0.017
23.0
0.746
0.685
23.0
AttFusion (2022)
0.529
0.252
22.0
0.878
0.751
24.0
0.094
0.021
23.0
0.738
0.673
23.0
TABLE I: Performance Comparison on OPV2V and DAIR-V2X. Comm denotes the communication volume calculated with Eq. ( 2 ).
Fig. 4: Visualization of detection results on the OPV2V and DAIR-V2X datasets under both LiDAR-based and camera-based configurations. Green represents ground truth box, and Red represents predicted box.
IDWT
Generator
AP30 ↑
AP50 ↑
✓
0.826
0.783
✓
✓
0.831
0.790
TABLE II: Ablation study results of the IDWT and Generator
Component
AP30 ↑
AP50 ↑
Base
0.826
0.783
Add-Fuse
0.831
0.788
Concat-Fuse
0.829
0.783
TABLE III: Ablation study results of the Different Component
Multilevel
AP30 ↑
AP50 ↑
Comm
1-level
0.831
0.790
20.0
2-level
0.825
0.768
18.0
3-level
0.801
0.721
18.0
TABLE IV: Ablation study results of the Multilevel Wavelet Transform
Communication-efficient collaborative perception studies how networked agents share useful sensor information with minimal bandwidth while improving their joint view of the scene.
Key Laboratory of Big Data & Artificial Intelligence in Transportation, Ministry of Education · School of Computer Science and Technology, Beijing Jiaotong University · Xiamen University