SMC Networks Barricade SMCWBR14S-3GN, Руководство пользователя

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C
HAPTER
7
| Wireless Configuration
Basic Settings
– 67 –
HT P
HYSICAL
M
ODE
S
ETTINGS
The HT Physical Mode section on the Wireless Settings Advanced page
includes additional parameters for 802.11n operation.
Figure 38: HT Physical Mode Settings
The following items are displayed in this section on this page:
◆ HT Operation Mode — Packets from 802.11n clients are referred to as
High Throughput (HT) Greenfield packets, in other words packets that
can be transmitted at rates of up to 300 Mbps assuming that HT
Channel Bandwidth is set to 20/40Mhz, see HT Channel Bandwidth next
page.
N
OTE
:
Some 802.11n wireless clients may be capable of transmission rates
of up to 600 Mbps, however the wireless 3G Broadband Router will only be
able to connect to them at a maximum transmission rate of 300 Mbps.
802.11b/g packets are referred to as non-HT packets, being transmitted at
lower throughput rates. HT mixed format frames contain a preamble
compatible with the non-HT receivers. HT Greenfield frames do not contain
a non-HT compatible part. Support for HT Greenfield format is optional. An
HT station that does not support the reception of an HT Greenfield format
frame must be able to detect that an HT Greenfield format frame is an HT
transmission (as opposed to a non-HT transmission). In this case the
receiver must decode the high throughput signal (HT-SIG) in the packet
header and determine if the HT-SIG cyclic redundancy check (CRC) passes.
(Default: Mixed)
◆
HT Channel Bandwidth — The wireless 3G Broadband Router
provides a channel bandwidth of 40 MHz by default giving an 802.11g
connection speed of 108 Mbps (sometimes referred to as Turbo Mode)
and a 802.11n connection speed of up to 150 Mbps. Setting the HT
Channel Bandwidth to 20 MHz slows connection speed for 802.11g and
802.11n to 54 Mbps and 74 Mbps respectively and ensures backward
compliance for slower 802.11b devices. (Default: 20MHz)