Field Strength Calculations Flashcards
What do electromagnetic waves consist of?
Oscillating electric and magnetic fields that propagate through space.
Which equations govern the behavior of electromagnetic waves?
Maxwell’s equations.
What is the characteristic impedance of free space (Z)?
Approximately 377 ohms (Ω).
What is the significance of the characteristic impedance in electromagnetic theory?
It defines the relationship between power density and electric field intensity.
What do Maxwell’s equations provide a framework for?
Understanding electromagnetic waves.
What does the wave equation derived from Maxwell’s equations determine?
The propagation of electric and magnetic fields.
At what speed do electromagnetic waves travel in free space?
The speed of light.
What does field strength measure?
The force exerted by an electric field on a unit charge at a given point.
In what units is field strength expressed?
Volts per meter (V/m).
Name factors influencing field strength.
- Transmission Power
- Antenna Characteristics
- Frequency of Operation
- Distance from the Source
- Environmental Obstructions
How is power density (PD) defined?
The power per unit area (W/m²).
How is electric field intensity (E) measured?
In volts per meter (V/m).
What is the relationship between power density and electric field intensity?
They are related by the equation PD = E² / Z, where Z is the characteristic impedance.
What is the effect of path loss on field strength?
Field strength decreases as the signal propagates through free space.
What factors does path loss impact in communication systems?
- Coverage Area
- Signal Quality
- Antenna Design
- Network Planning
What is the application of field strength calculations in wireless communication?
Ensuring proper coverage for mobile and Wi-Fi networks.
What is the role of field strength calculations in broadcasting?
Determining optimal transmission power for radio and TV stations.
What do field strength calculations help with in satellite communication?
Calculating link budgets for reliable signal transmission.
What regulatory aspect do field strength calculations ensure compliance with?
Electromagnetic field exposure limits.
Power Density Equation for E
E = square root of 377PD
Radiating Antenna Formula:
E = (30*EIRP) / r
Where:
EIRP = Effective Isotropic Radiated Power (W)
r = distance from the source (m)
Free-Space PAth Loss (FSPL) Formula:
Lfs = 32.44 + 20logd + 20logf
Where:
d = distance in km
f = frequency in MHz
It is a significant factor in determining the reliability of wireless communication systems
Path Loss
