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Appendix C: Facts About Digital Wireless Cameras
Appendix C: Facts About Digital Wireless Cameras
Wired VS Wireless Cameras
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.
Does a wireless camera require power?
Yes. Wireless cameras require two power sources: one connected to the camera, and the other to
the receiver.
How far can a wireless camera transmit a video signal?
In an open field (with line of sight), a typical wireless camera has a range between 250 to 450 feet.
In a closed environment---such as an interior of a house---the wireless camera range is between
100 to 150 feet. 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
1
. 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, routers may affect signal strength.
Range Limiting Factors
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Reflection
The signal
reflects back
Scattering
The signal
scatters back
into multiple
new signals
Refraction
The signal
bends as it
travels through
an object (i.e
glass window)
Diffraction
The signal
changes
direction as it
passes around
an object
Attenuation
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
