14
Appendix B:
Frequently Asked Questions
What are the differences between wired
and wireless cameras?
Does a wireless camera require power?
How far can a wireless camera transmit
a video signal?
A
wired camera
has a video cable that transmits
the video signal from the camera to a recording or
viewing device.
A
wireless camera
does not use a video cable.
Instead, it wirelessly transmits the video signal to a
wireless receiver that is connected to your recording
or viewing device. Although the typical digital wireless
camera is priced slightly higher than a wired camera,
wireless cameras can provide cost savings compared
to standard wired setups. For example, wireless
cameras do not require cabling to be run between the
camera and the viewing / recording device, which
reduces installation time and cost.
Yes. Wireless cameras require two power sources: one
connected to the camera, and the other to the receiver.
In an open field (with line of sight), a typical wireless
camera has a range between 250 to 500ft. In a
closed environment—such as an interior of a house—
the wireless camera range is between 100 to 165ft
The signal range varies depending on the type of
building materials and/or objects the wireless signal
must pass through.
Cubical walls, drywall, glass, and windows generally
do not degrade wireless signal strength. Brick,
concrete floors, and walls degrade signal strength.
Trees that are in the line of sight of the wireless camera
and receiver may impact signal strength.
The signal range also depends on whether there are
competing signals using the same frequency as the
camera. For example, signals from cordless phones or
routers may affect signal strength.
Range Limiting Factors
1
Reflection Scattering Refraction Diffraction Attenuation
The signal
reflects back
The signal scatters
back into multiple
new signals
The signal bends
as it travels
through an
object (e.g.
glass window)
The signal
changes direction
as it passes
around an object
The signal
strength weakens
as it passes
through an object
1
Source:
Xirrus (2010). “Wi-Fi Range Dynamics”.
Retrieved online at http://xirrus.gcsmarket.com/pdfs/
Xirrus_Wi-Fi_Range.pdf
