ZyXEL Communications MAX318M2W, Руководство пользователя

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Chapter 6 WiMAX
MAX318M2W User’s Guide
65
Frequency Ranges
The following figure shows the WiMAX Device searching a range of frequencies to
find a connection to a base station.
Figure 20 Frequency Ranges
In this figure, A is the WiMAX frequency range. “WiMAX frequency range” refers to
the entire range of frequencies the WiMAX Device is capable of using to transmit
and receive (see the Product Specifications appendix for details).
In the figure, B shows the operator frequency range. This is the range of
frequencies within the WiMAX frequency range supported by your operator
(service provider).
The operator range is subdivided into bandwidth steps. In the figure, each C is a
bandwidth step.
The arrow D shows the WiMAX Device searching for a connection.
Have the WiMAX Device search only certain frequencies by configuring the
downlink frequencies. Your operator can give you information on the supported
frequencies.
The downlink frequencies are points of the frequency range your WiMAX Device
searches for an available connection. Use the Site Survey screen to set these
bands. You can set the downlink frequencies anywhere within the WiMAX
frequency range. In this example, the downlink frequencies have been set to
search all of the operator range for a connection.
Certification Authority
A Certification Authority (CA) issues certificates and guarantees the identity of
each certificate owner. There are commercial certification authorities like
CyberTrust or VeriSign and government certification authorities. You can use the
WiMAX Device to generate certification requests that contain identifying
information and public keys and then send the certification requests to a
certification authority.