Cambium Networks cnReach N500, Руководство пользователя

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cnReach N500 User Guide System Configuration
phn-4673_003v000 (November 2018)
2-29
Max Payload Bytes
Max Payload Bytes for Access Point and End Point range from 64 to 1600 Bytes with a default setting
of 256. These settings are also referred to as “packet sizes”. To achieve high user data rates, larger
packets and higher modulation levels are required. In one slot time, there are fixed delays that are not a
function of packet size or data rate, so as more data is sent in a packet per slot time, the utilization
increases.
In noisy RF environments, small packets with faster, more complex modulation will help the radio get on
and off channels as quickly as possible to help mitigate bit error and packet loss.
If a targeted data rate is desired, there are multiple options of packet size and modulation that will
result with a similar data rate. The choice of shorter packets with more complex modulation or longer
packets with simpler modulation will be determined by the noise level in the environment.
Attention
Max Payload Bytes is one of the most commonly mis-configured parameters. Not only
must the value match for all radios in a PTP link or PMP cluster but they must be
compatible with the selected modulation or transmit modes. See the tables in Chapter 3:
Technical Reference for the tables associated with the band you are using.