1. Radio propagation Path loss Shadowing Multipath fading, ISI
Dr. Dóra Maros
Telecommunication
Radio propagation
Path loss
Shadowing
Multipath fading, ISI

2. Cells Earth Cell (satelite) Macrocell Size: 350m-20 km Microcell
Outdoor, rural, roads
Microcell
Size: 50m-300 m
Outdoor, city
Picocell
Size: some 10 m
Indoor

3. Radio Propagation in Mobile Networks

4. GSM 900, 1800, 1900 bands (2G)

5. UMTS Frequency Bands in 2000, new frequency bands
Duplexing
Uplink
Downlink
Bandwidth
UMTS-FDD
MHz
MHz
MHz
UMTS-TDD
MHz UL/DL
MHz UL/DL
MHz
Satelite
MHz
MHz
MHz
in 2000, new frequency bands
MHz, MHz (GSM bands!)
MHz
DECT
GSM 1800
1800
1900
2000
2100
2200
2500
2600
2700
UMTS FDD
Műhold
UMTS TDD
UMTS
[MHz]
Channel bandwidth: 5,10, or 20 MHz
Unpaired fr. bands
Paired fr. bands

6. LTE Bands
30 bands:
21 FDD
9 TDD

7. Directional Antennas
Adjustable antennas
GSM antennas

8. Omni antenna mounted on mobile tower
Omni antennas
Omni antenna mounted on mobile tower
„Handy” omni antenna

9. Microwave Antennas
Micro antennas: connections towards the core network (some ten GHz)

10. Multiple sector antennas in the same cell
3G/4G Antennas
Multiple sector antennas in the same cell
MIMO antennas (LTE)

11. Indoor Antennas (examples)

12. Radio propagation I. Frequency and wavelength
The wavelength is inversly proportional to the frequency of elektromagnetic wave :
λ = c/f, where
λ - wavelength (m)
c - velocity of electromagnetic wave
(in vacuum and in the air about 3*108 m/s, accurate value: m/s)
f - frequency (Hz)
Example:
1. f=900 MHz (9*108 Hz) λ =?
3*108 / 9*108 = 3/9 [m] ~ 0,33 [m]
f=2,6 GHz (2,6*109)
3*108 / 2,6*109 = 1,154 * 10-1 ~ 0,1154 [m]

13. Radio propagation II. Path loss
RSL Received Signal Level (dB)
Free space attenuation:
a0 = 20 log (4Πd/λ)
a0 = 20 log (df) + 28,14
d (distance from antenna)

14. Radio Propagation III. Propagation Models
Makrocell propagation models:
Relative small traffic (rural, road), high speed of movement (>100 km/h)
Hata, COST231
Mikrocell propagation models:
High traffic (urban, suburban), smaller speed of movement (30-80 km/h)
Walfish-Ikegami modell, COST 231
Indoor propagation models:
Mootley-Keenan (félempirikus)
Ray-tracing

15. Radio Propagation IV. Shadowing
RSL (dB)
Base Station
Mobile
Equipment
Mean value
d (distance from antenna)
Slow fading caused by shadowing

16. Radio Propagation V. Multipath Fading
Base Station
Mobile Equipment
Fast fading caused by reflections