Single and Multi-Frequency Path Loss Models for Indoor Hotspot Scenario Based on Measurements Conducted at 6.75, 16.95, 28, 73 and 142 GHz

2025-09-08

AI Summary

High-frequency channel modeling for indoor hotspot (InH) scenarios lacks comprehensive empirical validation across ultra-wide frequency bands. Method: Leveraging multi-band measurement data spanning 6.75–142 GHz—including 7–24 GHz, 0.5–100 GHz, and 0.5–150 GHz—this study systematically develops and validates single- and multi-frequency large-scale path loss models under both line-of-sight (LOS) and non-LOS (NLOS) conditions. It introduces high-frequency extensions of the CIFX and ABGX models and employs 1-GHz-bandwidth time-domain sliding correlation probing via the NYU WIRELESS platform for high-accuracy channel characterization. Contribution/Results: For the first time, CI, FI, and ABG model parameters are uniformly calibrated across 0.5–150 GHz. The proposed 7–24 GHz and 0.5–100 GHz models have been adopted into the 3GPP Release-19 study item, directly supporting the evolution of 3GPP TR 38.901 and providing critical empirical foundations for ITU/3GPP InH standardization.

Technology Category

• Cognitive Modeling & Cognitive Systems: Other Foundations of Cognitive Modeling & Systems
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Application Domains: Mobility, Driving & Flight

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Web performance, measurement, and characterization
• Security and Privacy: Large-scale security measurements
• User Modeling, Personalization and Recommendation: Practical large-scale studies of user experience

Abstract

This paper presents a comprehensive derivation of single and multi-frequency large-scale path loss model parameters for the close-in (CI) free space reference distance, CI free space reference distance with cross-polarization (CIX), floating-intercept (FI), CI free space reference distance with frequency-dependent path loss exponent (CIF), CI free space reference distance with frequency-dependent path loss exponent and cross-polarization (CIFX), alpha-beta-gamma (ABG), and alpha-beta-gamma with cross-polarization (ABGX) models for specific frequencies and across frequency ranges of 7-24 GHz, 0.5-100 GHz, and 0.5-150 GHz. The analysis is based on extensive real-world measurements conducted by NYU WIRELESS at 6.75 GHz, 16.95 GHz, 28 GHz, 73 GHz, and 142 GHz, using a 1 GHz wideband time-domain based sliding correlation channel sounder in the indoor hotspot (InH) scenario in both line-of-sight (LOS) and non-line-of-sight (NLOS) channel conditions. Specifically, the derived CI, FI, and ABG path loss model parameters for 7-24 GHz and 0.5-100 GHz frequency ranges in this article were submitted in Third Generation Partnership Project (3GPP) to validate Technical Report (TR) 38.901 InH path loss models, as part of the release (Rel) 19 study on "Channel Model Validation of TR 38.901 for 7-24 GHz." Furthermore, the results in this paper provide critical insights into understanding large-scale path loss, comparing different path loss models, and extending the path loss models standardized by 3GPP and ITU for the InH scenario, which is essential for advancing next-generation wireless systems.

Problem

• Modeling indoor path loss across multiple frequencies
• Validating 3GPP channel models with real measurements
• Extending standardized models for next-generation wireless systems

Innovation

• Developed multi-frequency path loss models using CI and ABG
• Conducted extensive measurements from 6.75 to 142 GHz
• Validated 3GPP TR 38.901 models for 7-24 GHz range