Around-Corner and Over-Top 28 GHz Propagation in Manhattan
This work presents a detailed 28 GHz measurement campaign in West Harlem, Manhattan, to characterize challenging urban Non-Line-of-Sight (NLOS) mmWave propagation paths. We propose two novel empirical models: the Street-Clutter-NLOS and Over-Top-NLOS models, tailored for next-generation base station placement and MU-MIMO system design.
Key Contributions:
- New Propagation Models: The Street-Clutter-NLOS model captures path loss through near-corner obstructions like fences, trash bins, poles, and vehicles. The Over-Top-NLOS model captures elevated reflections over rooftops.
- High Accuracy: Street-Clutter-NLOS achieves 6.4 dB RMSE, outperforming the 3GPP UMi-NLOS model by over 5 dB. Over-Top-NLOS achieves sub-4 dB RMSE using building height, width, and separation as predictors.
- Dense Urban Validation: Measurements span 10 transmitter locations and over 300 receiver positions in highly cluttered urban blocks, using 28 GHz directional horn antennas and motorized rotation to capture AoA and path loss.
- Implications for MU-MIMO: AoA diversity persists even in deep NLOS; spatial orthogonality is often preserved beyond corners or rooftops, supporting viable user separation for future 5G and 6G systems.
- Design Insight: Models suggest when and where to expect multi-user viability, spatial decorrelation, and link blockage—critical for real-world mmWave network deployment.
Measurement Setup:
- Tx height: 3.4 m (urban lamppost simulation)
- Rx: 24 dBi rotating horn antenna capturing full angular scans
- Measurement area: 2.5 city blocks in NYC
- Tx-Rx distances: up to 300 m in NLOS scenarios
Conclusion: These results provide a new blueprint for mmWave network designers, especially for NLOS-heavy dense urban regions. Our models enable accurate prediction of both path loss and spatial angle spread, improving both link budget planning and multi-user beamforming performance in challenging 28 GHz deployments.
Presentation & Access:
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