RF Neulink NL6000, Руководство пользователя

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RF Neulink 24 NL6000 User Guide
However, because you are less likely to lose data with Enhanced
Telemetry mode than with Basic Telemetry mode, you can use a larger
Maximum Packet Size. A larger packet size can compensate for the lower
percentage of user data in each packet and provide good throughput on an
occasionally corrupt channel.
Why not use Basic Telemetry Mode for this scenario?
Basic Telemetry
mode is not useful when you expect a corrupt channel because a single
transmission error will cause a packet failure. Lost packets will degrade
throughput. Basic Telemetry mode cannot recover data errors, so
throughput would be poor.
Why not use Mobile Data Mode for this scenario?
Mobile Data mode
requires that the interleaver be filled for each packet. If the data packets
are smaller than the interleaver size, throughput will suffer because the
interleaver is “filled” prior to transmission. Since fading is not a big issue
in this scenario, the interleaver is not necessary.
Scenario #3
Description:
You have fluctuating signal strength and a less reliable path
between the radio modem units. You expect noise bursts, RF interference,
or signal fading to corrupt the radio data link. The remote unit is moving,
or it is located in an area where the surroundings are moving, such as a
busy street.
Best Choice: Mobile Data Mode
Because you expect a corrupt channel, use the mode that has the greatest
amount of error control. Mobile Data mode includes three types of error
control, Reed-Solomon forward error correction, error detection, and a
block interleaver. This mode provides for maximum transmission
reliability on a corrupt channel. Since the packet size is large, any data
added to the packet to fill the interleaver is insignificant.
Because you are more likely to recover from transmission errors with
Mobile Data mode, you can use a large Maximum Packet Size. A larger
packet size can compensate for the lower percentage of user data in each
packet and provide good throughput on a corrupt channel.
Why not use Basic Telemetry Mode for this scenario?
Basic Telemetry
mode is not useful when you expect a corrupt channel because it uses error
detection only. Basic Telemetry mode cannot recover data errors, so
throughput would be poor.
Why not use Enhanced Telemetry Mode for this scenario?
Enhanced
Telemetry mode provides error correction, but if both the signal strength
and path are poor, you might need to reduce the Maximum Packet Size to