Submitted:
20 March 2026
Posted:
23 March 2026
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Abstract
Keywords:
1. Introduction
2. Related Work

2.1. Innovation and Involvements
2.2. Challenges in Traditional Beamforming for mmWave Systems
3. System Design
4. Design of DLBF
4.1. BF with NN Architecture
4.2. Input of the DLBF
4.3. Loss Function
4.4. Implementation Details of the DLBF
5. Results and Discussion
5.1. Spectral Efficiency Gains
5.2. Consequences of PNR
5.3. Effect of Lest
5.4. Effect of Model Mismatch
| Method | Main Operation | Complexity (FLOPs) | Relative Speed | Adaptability | Comments |
| DL-Based Beamforming [11] | Forward pass through trained NN | O(L⋅N2h) | Very Fast (once trained) | High | Inference is fast; complexity depends on layers (L) and hidden units (Nh) |
| SVD-Based Precoding | SVD of channel matrix H∈CM×K | O(MK2+K3) | Slower | Low | Requires full CSI; computationally heavy for large MIMO |
| ZF / MMSE Precoding | Matrix inverse and multiplication | O(MK2+K3) | Moderate | Low | Sensitive to noise and interference; less effective in low SNR |
| Codebook-Based Beamforming | Exhaustive or hierarchical search over set | O(N⋅M) | Depends on codebook size | Limited | Scales poorly with large antenna arrays and codebook sizes |
| Optimization-Based (e.g., SDR) | Iterative convex/non-convex optimization | O(Niter⋅M3) | Very Slow | Moderate | Provides accurate results but unsuitable for real-time use |
- M: Number of antennas
- K: Number of users
- N: Number of codebook entries
- L: Number of neural network layers
- Nh: Number of neurons per hidden layer
- Niter: Number of iterations in optimization
5.5. Generality of DLBF
| Metric | Conventional | Proposed | ||
|---|---|---|---|---|
| Training Loss | Validation Loss | Training Loss | Validation Loss | |
| Final MSE @ Epoch 100 | 0.0121 | 0.0138 | 0.0028 | 0.0031 |
6. Conclusion
Statement of Ethical Approval
Conflicts of Interest
References
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| PNR (dB) | Spectral Efficiency (SE) (bits/Hz/s) | ||
|---|---|---|---|
| HBF (4) | HBF (5) | DLBF (proposed) | |
| -20 | 10 | - | 14 |
| 0 | 15 | - | 18 |
| 20 | - | 26 | 34 |
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