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Radio Mobile - RF propagation simulation software |
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 When using the information on these page please note the Disclaimer.
Be aware that this information can be inaccurate in your situation. Use this information with care!
RX Sensitivity
Some values for various sensititivies.
| Modulation type |
treshold |
Sensitivity |
| Narrowband FM |
12 dB SINAD |
-120 dBm |
| TETRA Handheld |
4% BER |
-112 dBm |
The P's and Q's from TV reception: http://www.utaharc.org/utah_atv/psandqs.html
 These values can be used for ATV prediction.
| Report |
treshold |
Signal/Noise ratio |
Sensitivity |
| P5 |
no discernible noise |
>45 dB |
>1000 microvolt |
| P4 |
very slightly noisy |
35-45 dB |
200-1000 microvolt |
| P3 |
somewhat noisy |
20-35 dB |
50-200 microvolt |
| P2 |
definitely noisy |
8-20 db |
15-50 microvol |
| P1 |
I can barely see your ID, OM... |
3-8 db |
5-15 microvolt |
| P0 |
Is there really a signal there? |
<3 db |
<5 microvolt |
RF planning targets
Some planning targets for various technologies and services.
| Modulation type |
treshold |
Sensitivity |
| DAB-T Outdoor Car Radio |
(service unknown) |
48 dB(uV/m) |
| DAB-T Indoor Kitchen Radio |
(service unknown) |
57 dB(uV/m) |
| DAB-T Pocket Radio |
(service unknown) |
64 dB(uV/m) |
Additional losses
In addition to the impact of terrain, engineers must also consider external losses such as body absorption, building losses, and values introduced in various circumstances. The following table provides some general guidelines for external losses.
Position of a handheld radio
| Measured Losses |
150-170 MHz |
450-470 MHz |
| Handheld, antenna held vertical |
-6 dB |
-17 dB |
| Handheld, antenna held angled |
-10 dB |
-18 dB |
| Handheld, Hip-mount |
-17 dB |
-17 dB |
In-Vehicle losses
| Measured Losses |
150-170 MHz |
450-470 MHz |
| Radio on driver’s left hip, antenna clear: |
-25 dB |
-24 dB |
Radio laying on seat, speaker up with antenna
toward front: |
-36 dB |
-16 dB |
Radio connected to vehicular charger and unity
gain antenna on rooftop: (15-foot RG-58/U coax) |
-2 dB |
-4 dB |
These loss values can be used when determining the amount of signal available at a receiver’s input terminals for a given field strength.
Building penetration losses
Additional measured losses inside buildings should be included when designing a system for operation of mobile units inside buildings:
| Measured Losses at Building floor |
VHF |
UHF |
| Basement |
-34 dB |
-27 dB |
| 1st |
-29,5 dB |
-23,5 dB |
| 3rd |
-26 dB |
-20 dB |
| 5th |
-23 dB |
-15 dB |
| 10th |
-12 dB |
-3,5 dB |
| 14th |
-7,8 dB |
+2 dB |
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Source: “Two-Way Personal Radio System Design,” General Electric Co.
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