Lorex LW2702 series, Инструкция по эксплуатации

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Appendix B: About Digital Wireless Technology
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Appendix B: About Digital Wireless Technology
The Digital Wireless signal transmission type used by the Lorex LW2702 series is also known as
FHSS –Frequency Hopping Spread Spectrum . This type of signal is highly resistant to
deliberate jamming as it generates a channel hopping sequence using an algorithm generated
by the receiver system.
The 2.4GHz (2.400-2.480Ghz) band is being divided into sections or paths of 2MHz per section,
and each second the transmission signal hops hundreds of times in a specified sequence within
this frequency range. The overall bandwidth required for frequency hopping is much wider then
2MHz however because transmission occurs only on a small section of this bandwidth at any
given time, the signal being transmitted does not suffer from greatly reduced signal
degradation and also avoids blocked paths other devices who act as sources of competing
signals. The strength of the signal being transmitted is set to be from 13.5-16dBm, which is
much higher then the analog transmission signal allowed by authorities around the Globe.
When an image is captured by the camera it is instantly converted from an analog to digital
signal and packaged into small packets. With each successful transmission via the 2 MHz paths
discussed above, the packets of information containing images are delivered to the receiver and
decoded into analog information. The information can then be displayed on devices that are
connected to the wireless receiver (RX).
A device pairing process is required to synchronize the transmitter (TX, Camera) and the
receiver (RX). This allows the transmitter and receiver to be on the same frequency and use the
same algorithm for frequency hopping. This ensures that only the paired transmitter and
receiver can maintain communication signal by hopping to the same frequency paths at the
exact same time. As a result, the chance that other devices within the same frequency range
are on the same frequency, at the same time and in the same order is extremely unlikely. Note
that the pairing process is already done at the factory for products that ship within the same
packaging. Only when add-on devices are purchased is a pairing process required.