Cirronet HopNet 10 Series, Руководство пользователя

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HopNet Family of Products 800281Rev. B 4
About Hopnet Products
Introduction
This section provides operational information about the HopNet products.
Operating Frequency
The HopNet family operates in the 2.4 GHz ISM band that allows for license-free use
and worldwide compliance.
HopNet Frequency Hopping Spread Spectrum Advantages
In the frequency domain, a multipath fade can be described as a frequency selective
notch that shifts in location and depth over time. Multipath fades typically occupy
five percent of the band. A conventional radio system typically has a five percent
chance of signal impairment at any given time due to multipath fading.
Frequency Hopping Spread Spectrum reduces the vulnerability of a radio system to
both interference from jammers and multipath fading by distributing or spreading
the signal over a larger region of the frequency band.
The fade resistant, HopNet frequency-hopping technology employs up to 75
channels and switches channels over 100 times a second to achieve high reliability
throughput.
HopNet Data Integrity
An on-board 3 KB buffer and error correcting over-the-air protocol ensure data
integrity even in the presence of weak signals or jammers. The serial interface
handles both data and control of asynchronous data rates of up to 230 Kbps.
Flexible Power Management
You can set the transmit power at 10 milliwatts or 100 milliwatts. Reduced power
can reduce the size of the coverage zone, which may be desirable for multiple
network indoor applications. You can also place the transceiver module in a power-
save mode, which enables smart power management. Smart power management
allows a remote unit to drop into a lower current standby mode during transmission
or receiving gaps.
This feature also allows Hopnet products to be used in various countries where the
output power requirements may vary due to regulation.