# Indoor and Outdoor Penetration Loss Measurements at 73 and 81 GHz

## TL;DR

This study measures millimeter-wave penetration losses at 73 and 81 GHz for various indoor and outdoor building materials, providing valuable data for mmWave communication system design.

## Contribution

It provides new empirical data on penetration losses of common building materials at 73 and 81 GHz, including indoor and outdoor differences.

## Key findings

- Outdoor materials have higher penetration losses than indoor materials.
- Average penetration loss for wood is 2-9 dB, and for glass is 16-23 dB.
- Maximum measured loss is 26.5 dB through outdoor tinted glass.

## Abstract

In this paper, we present millimeter-wave (mmWave) penetration loss measurements and analysis at E-bands-73 GHz and 81 GHz. Penetration loss was measured for common building materials such as clear glass, metal, tinted glass, wood, and drywall on the campus of Boise State University in the city of Boise. A horn antenna with a gain of 24 dBi was used at the transmitter and receiver at both bands, and both antennas were boresight-aligned with respect to the test material. A total of twelve locations were selected to test five materials. We tested two indoor materials (clear glass and wood) in at least two locations to determine the effect of penetration loss of materials in similar compositions. The average penetration loss and standard deviation were estimated for these indoor materials. We measured an average penetration loss of 2 to 9 dB for wood and glass, respectively. Furthermore, we measured the penetration loss of common indoor and outdoor building materials. We studied that outdoor materials had larger penetration losses, e.g., we obtained a penetration loss of 22.69 dB for outdoor metal, where this value dropped to 16.04 dB for indoor metal at 73 GHz. Similar results were also obtained for the 81 GHz channel, where the largest penetration loss was measured to be 26.5 dB through a tinted glass door in an outdoor setting.