IgniteNet SunSpot AC1200, Руководство пользователя

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Chapter 4
| Wireless Settings
Radio Settings
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ACK Timeout — Sets the acknowledgement timeout, which is used primarily
for long-distance connections. This timeout is used to make an adjustment for
link distance. It is based on the amount of time, in microseconds, that it should
take to transmit a frame to the other end of the link, be processed by the
receiving device, and have the ACK frame created and returned to the sending
device. (Range: 0-255 microseconds; Default: 0 microseconds)
◆
Fragmentation Thresh. — Sets the maximum frame size above which packets
are fragmented. This reduces the time required to transmit the frame, and
therefore reduces the probability that it will be corrupted (at the cost of more
data overhead). (Range: 256-2346 bytes; Default: 2346 bytes)
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RTS Threshold — Sets the packet size threshold at which a Request to Send
(RTS) signal must be sent to a receiving station prior to the sending station
starting communications. The access point sends RTS frames to a receiving
station to negotiate the sending of a data frame. After receiving an RTS frame,
the station sends a CTS (clear to send) frame to notify the sending station that it
can start sending data.
If the RTS threshold is set to 1, the access point always sends RTS signals. If set
to 2346, the access point never sends RTS signals. If set to any other value, and
the packet size equals or exceeds the RTS threshold, the RTS/CTS (Request to
Send / Clear to Send) mechanism will be enabled.
The access points contending for the medium may not be aware of each other.
The RTS/CTS mechanism can solve this “Hidden Node Problem.” (Range: 1-2346
bytes: Default: 2346 bytes)
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SGI — The 802.11n draft specifies two guard intervals: 400ns (short) and 800ns
(long). Support of the 400ns Short Guard Interval is optional for transmit and
receive. The purpose of a guard interval is to introduce immunity to
propagation delays, echoes, and reflections to which digital data is normally
very sensitive. Enabling the SGI sets it to 400ns. (Default: Disabled)
20 dBM (100 mW) √
21 dBM (125 mW) √
22 dBM (158 mW) √
23 dBM (199 mW) √
24 dBM (251 mW) √
25 dBM (316 mW) √
26 dBM (398 mW) √
27 dBM (501 mW) √
Table 4: Tx Power (Continued)
Power Radio 0 (5 GHz) Radio 1 (2.4 GHz)