---
title: "Conditions for Okumura and Hata models"
subject: "Wireless Communication"
chapter: 3
key: "semester_7/wireless_communication:okumura-hata-conditions"
source: https://www.bctengineer.com/q/semester_7/wireless_communication/okumura-hata-conditions
site: BCT Engineering
---

# Conditions for Okumura and Hata models

Wireless Communication · Chapter 3: Radio Wave Propagation in Mobile Networks

- Asked in: 2080 Chaitra, 2+2 marks; 2079 Chaitra, 2+2 marks (asked 2 times)
- Video: [Outdoor Propagation Model Okumura - Mobile Radio Propagation - Mobile Communication System](https://www.youtube.com/watch?v=GqploKEmD3w) — Ekeeda
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_7/wireless_communication/okumura-hata-conditions
- Whole chapter: https://www.bctengineer.com/md/semester_7/wireless_communication/chapter-3

## Question

What are the necessary conditions for Okumura and Hata Model?

## Short answer

Okumura: 150-1920 MHz, 1-100 km, hte 30-1000 m, hre up to 10 m, quasi-smooth terrain, urban/suburban/open curves. Hata: 150-1500 MHz, 1-20 km, hte 30-200 m, hre 1-10 m, macrocell only; COST-231 extends to 2 GHz.

## Answer

Both models are empirical, so they are valid only within the range of the measurements on which they are based.

#### Okumura model
- **Frequency:** 150 MHz to 1920 MHz (often extrapolated up to 3000 MHz).
- **Distance:** 1 km to 100 km between transmitter and receiver.
- **BS antenna effective height (hte):** 30 m to 1000 m.
- **Mobile antenna height (hre):** reference 3 m, correction for up to about 10 m.
- Terrain should be **quasi-smooth**; corrections are needed for hilly terrain, water, slope, etc.
- Environment must be classed as urban, suburban or open area; correction curves (Amu, GAREA) are read for these.

#### Hata model
- **Frequency (fc):** 150 MHz to 1500 MHz.
- **BS antenna height (hte):** 30 m to 200 m.
- **Mobile antenna height (hre):** 1 m to 10 m.
- **Distance (d):** 1 km to 20 km.
- Suited to **large-cell** (macrocell) systems; not suitable for personal communication systems with cell radius about 1 km. For 1500–2000 MHz, the COST-231 extension is used.

| Parameter | Okumura | Hata |
|---|---|---|
| Frequency | 150–1920 MHz | 150–1500 MHz |
| Distance | 1–100 km | 1–20 km |
| hte | 30–1000 m | 30–200 m |
| hre | up to 10 m | 1–10 m |
| Form | Curves + formula | Closed-form formula |

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. The Okumura model is valid for frequencies of:
   A. 500 kHz-30 MHz
   B. 1500-6000 MHz
   C. 30-300 MHz
   D. 150-1920 MHz
   Answer: D. Often extrapolated to 3000 MHz. (Key point: Okumura frequency)

2. The Hata model is valid for distances of:
   A. 20-100 km
   B. 1-20 km
   C. 1-100 km
   D. 100-500 m
   Answer: B. Hata d = 1-20 km; Okumura goes to 100 km. (Key point: Hata distance)

3. Valid BS antenna height range for Hata is:
   A. 200-1000 m
   B. 30-1000 m
   C. 1-10 m
   D. 30-200 m
   Answer: D. hte = 30-200 m (Okumura 30-1000 m). (Key point: Hata BS height)

4. Hata is not suitable for:
   A. Large macrocell systems
   B. 150-1500 MHz
   C. PCS with cell radius about 1 km
   D. Urban areas
   Answer: C. For 1500-2000 MHz, COST-231 extension is used. (Key point: Hata suitability)

## Related in Wireless Communication

- [Okumura vs Hata; delay spread numerical](https://www.bctengineer.com/question.md?key=semester_7%2Fwireless_communication%3Aokumura-hata-delay-spread) — Wireless Communication, chapter 3
- [Numerical: maximum cell radius using Hata model](https://www.bctengineer.com/question.md?key=semester_7%2Fwireless_communication%3Ahata-max-cell-radius) — Wireless Communication, chapter 3
- [Okumura model and median path loss numerical](https://www.bctengineer.com/question.md?key=semester_7%2Fwireless_communication%3Aokumura-model-median-path-loss) — Wireless Communication, chapter 3
- [Numerical: Okumura path loss, EIRP and received power](https://www.bctengineer.com/question.md?key=semester_7%2Fwireless_communication%3Aokumura-eirp-received-power) — Wireless Communication, chapter 3, asked 3×
- [Numerical: Okumura median path loss (unity gain)](https://www.bctengineer.com/question.md?key=semester_7%2Fwireless_communication%3Aokumura-median-loss-unity-gain) — Wireless Communication, chapter 3, asked 3×
- [Numerical: Okumura T-R separation for 167 dB](https://www.bctengineer.com/question.md?key=semester_7%2Fwireless_communication%3Aokumura-separation-distance) — Wireless Communication, chapter 3

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