# Unmanned Aerial Vehicle Propagation Channel over Vegetation and Lake Areas: First- and Second-Order Statistical Analysis

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## Abstract

**:**

## 1. Introduction

## 2. Materials

#### 2.1. Unmanned Aerial Vehicle

#### 2.2. XBee Module

## 3. Mathematical Formulation and Methodology

#### 3.1. Filtering

#### 3.2. Large-Scale Attenuation

#### 3.3. Small-Scale Fading

#### 3.3.1. Level Crossing Rate

#### 3.3.2. Doppler Frequency

## 4. Measurement Scenario

#### 4.1. Measurement Scenario 1: Lake

#### 4.2. Measurement Scenario 2: Caatinga

#### 4.3. Measurement Scenario 3: Mixed

## 5. Results

## 6. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Appendix A

## References

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**Figure 2.**Equipment used in measurement campaigns. (

**a**) UAV with XBee and power battery modules. (

**b**) Base station for collecting measurement data.

**Figure 3.**Lake photos taken at different heights. (

**a**) Photo taken with UAV over the lake at a height of 8 m. (

**b**) Photo taken with UAV over the lake at a height of 80 m. (

**c**) Showing the base station (BS) and the lake area.

**Figure 4.**Caatinga biome region. (

**a**) Flight region over the Caatinga vegetation. (

**b**) Area of the flight over the Caatinga vegetation.

**Figure 5.**Mixed scenario. (

**a**) Mixed scenario photo taken by the UAV at 80 m. (

**b**) Full view of the mixed scenario.

**Figure 9.**Estimated CDFs over the lake for the same height. (

**a**) CDFs over the lake at 8 m. (

**b**) CDFs over the lake at 80 m.

**Figure 10.**Estimation of CDFs over the lake at the same speed. (

**a**) CDFs over the lake at 1 km/h. (

**b**) CDFs over the lake at 3 km/h.

**Figure 11.**Estimation of CDFs for the Caatinga and Mixed environments. (

**a**) CDFs for the Caatinga region. (

**b**) CDFs for mixed region.

**Figure 12.**Doppler frequency estimation. (

**a**) Doppler frequency for Lake region. (

**b**) Doppler frequency for Caatinga and Mixed regions.

**Figure 13.**Estimated speeds. (

**a**) Estimated speeds for Lake region. (

**b**) Estimated speeds for the Caatinga and Mixed regions.

Work | Frequency | UAV | Scenario | Height | Channel Statistics |
---|---|---|---|---|---|

[10] | 2 GHz | Airship | Urban | 100–170 m | PDF, CDF, AFD, LCR, PSD, AF |

[11] | 2 GHz | Airship | Urban | 150–300 m | PL |

[12] | 5.76 GHz 1.817 GHz | Hexacopter | Suburban | 0–50 m | PL, SF, K, RMS, CDF |

[13] | 4.3 GHz | Quadcopter | Open field, Suburban | 4–16 m | PL, SF, $\mu $, $\epsilon $, PDF, CDF, RMS, BC |

[14] | 2.4 GHz | Hexacopter | Laboratory, Open air | 10–40 m | PL, PAS, K, |

[15] | 802.11a | Quadcopter | Open field | 15–110 m | PL, PAS, CDF |

[16] | 802.11a | Quadcopter | Open field, Field area | 20–100 m | PL |

[17] | 802.11a | Fixed Wing | Aerodrome | 46 m | PL |

[18] | 802.11a/g, 900 MHz | Fixed Wing | Aerodrome, Rural | 46 m, 107–274 m | PL |

[19] | GSM, UMTS | Fixed Wing, Capture balloon | Urban, Rural | 0–500 m | PL |

[20] | GSM, UMTS, LTE | Weather balloon | Urban | 11–18 m | PL |

[21] | LTE (800 MHz) | Hexacopter | Rural | 15–100 m | PL, SF |

[22] | LTE (850 MHz) | Quadcopter | Suburban | 15–120 m | PL, SF |

[23] | 2 GHz | Airship | Urban, Wooded Region | 100–170 m | CDF, DG, AFD, LCR |

[24] [25] | 5.8 GHz | Octocopter | Residential | - | RMS, DS, CDF |

[26] | 802.11b/g | Fixed Wing | Agricultural region | 75 m | AF, DG |

[27] | PCS, AWS, 700 MHz | Quadcopter | Mix Suburban | 122 m | PL, CDF |

[28] | EDGE, HSPA+, LTE | Hexacopter | - | 10–100 m | RTT, J |

[29] | 909 MHz | Quadcopter | Open field, Simulated Village | 40–60 m | PL, PES |

[30] | 2/3.5/5.5 GHz | HAP airship | Built-up areas | - | SF |

[31] | 2.585 GHz | Hexacopter | Suburban | 15–300 m | PDP, RMS, DS |

[32] | 3.4/3.8 GHz | Commercial UAV | Open area | 5–15 m | PDP, RMS |

This work | 915 MHz | Quadcopter | Lake, Caatinga | 8–80 m | PL, LCR, CDF, DS, SF, K, $\mu $, $\epsilon $, m, $\beta $, $\sigma $ |

Schedule | Temperature | Average Wind Speed |
---|---|---|

10:00 | 31 °C | 31 km/h |

11:00 | 31 °C | 28 km/h |

12:00 | 31 °C | 33 km/h |

13:00 | 31 °C | 28 km/h |

14:00 | 30 °C | 33 km/h |

15:00 | 30 °C | 35 km/h |

16:00 | 30 °C | 28 km/h |

17:00 | 29 °C | 24 km/h |

Velocity | Height | Traveled Distance |
---|---|---|

1 km/h | 8 m | 120 m |

1 km/h | 80 m | 150 m |

3 km/h | 8 m | 120 m |

3 km/h | 80 m | 150 m |

Velocity | Height | Traveled Distance |
---|---|---|

1 km/h | 80 m | 130 m |

3 km/h | 80 m | 250 m |

Velocity | Height | Traveled Distance |
---|---|---|

1 km/h | 80 m | 150 m |

3 km/h | 80 m | 150 m |

Environment | Path Loss Exponent | Speed (km / h) | Height (m) |
---|---|---|---|

Lake | −7.8 | 1 | 8 |

Lake | −8.9 | 3 | 8 |

Lake | 2.9 | 1 | 80 |

Lake | 2.0 | 3 | 80 |

Mixed region | 3.7 | 1 | 80 |

Mixed region | 3.8 | 3 | 80 |

Caatinga | 3.7 | 1 | 80 |

Caatinga | 1.9 | 3 | 80 |

Environment | Height (m) | Speed (km/h) | Average ($\mathit{\mu}$) | Standard Deviation ($\mathit{\sigma}$) | Window |
---|---|---|---|---|---|

Lake | 8 | 1 | −0.036457 | 4.9594 | 10 |

Lake | 8 | 3 | −0.00010684 | 5.1219 | 5 |

Lake | 80 | 1 | 0.014171 | 1.5940 | 15 |

Lake | 80 | 3 | 0.019407 | 1.3563 | 15 |

Mixed region | 80 | 1 | 0.021741 | 1.8036 | 10 |

Mixed region | 80 | 3 | 0.023567 | 1.4659 | 20 |

Caatinga | 80 | 1 | 0.0089469 | 2.6579 | 10 |

Caatinga | 80 | 3 | −0.0052443 | 3.0010 | 15 |

Window | Nakagami (m, $\mathit{\Omega}$) | Rice (K) | Rayleigh ($\mathit{\sigma}$) | Weibull ($\mathit{\beta}$, $\mathit{\lambda}$) | Height (m) | Environment | Velocity (km/h) |
---|---|---|---|---|---|---|---|

10 | 0.42621, 4.0043 | 0.00033815 | 1.415 | 1.1251, 1.4969 | 8 | Lake | 1 |

5 | 0.54171, 1.8553 | 0.00032789 | 0.96315 | 1.3129, 1.1415 | 8 | Lake | 3 |

15 | 0.4374, 2.6966 | 0.00027749 | 1.1612 | 1.1512, 1.2552 | 80 | Caatinga | 1 |

15 | 0.43961, 2.6205 | 0.00027911 | 1.1447 | 1.1688, 1.2184 | 80 | Caatinga | 3 |

10 | 0.44587, 2.4439 | 0.0002916 | 1.1054 | 1.1751, 1.1859 | 80 | Mixed region | 1 |

20 | 0.37927, 3.2004 | 0.00020356 | 1.265 | 1.0619, 1.2123 | 80 | Mixed region | 3 |

10 | 0.35111, 2.3994 | 0.00027483 | 1.0953 | 1.0072, 1.0094 | 80 | Lake | 1 |

15 | 0.37418, 3.3069 | 0.00019419 | 1.2859 | 1.0548, 1.2181 | 80 | Lake | 3 |

UAV Speed (km/h) | Doppler Frequency (Minimum–Maximum) |
---|---|

1 | 0–0.86 Hz |

3 | 0–2.6031 Hz |

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**MDPI and ACS Style**

Leite, D.L.; Alsina, P.J.; de Medeiros Campos, M.M.; de Sousa, V.A., Jr.; de Medeiros, A.A.M.
Unmanned Aerial Vehicle Propagation Channel over Vegetation and Lake Areas: First- and Second-Order Statistical Analysis. *Sensors* **2022**, *22*, 65.
https://doi.org/10.3390/s22010065

**AMA Style**

Leite DL, Alsina PJ, de Medeiros Campos MM, de Sousa VA Jr., de Medeiros AAM.
Unmanned Aerial Vehicle Propagation Channel over Vegetation and Lake Areas: First- and Second-Order Statistical Analysis. *Sensors*. 2022; 22(1):65.
https://doi.org/10.3390/s22010065

**Chicago/Turabian Style**

Leite, Deyvid L., Pablo Javier Alsina, Millena M. de Medeiros Campos, Vicente A. de Sousa, Jr., and Alvaro A. M. de Medeiros.
2022. "Unmanned Aerial Vehicle Propagation Channel over Vegetation and Lake Areas: First- and Second-Order Statistical Analysis" *Sensors* 22, no. 1: 65.
https://doi.org/10.3390/s22010065