Mid-tech RX 400p, Руководство пользователя

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RX 400p
2-3 98-05044
R1
The BER number indicates the number of unsuccessfully decoded symbols in a
moving window of 2048 symbols. Due to the use of forward error correction
algorithms, one symbol is composed of two bits.
A lower BER indicates that data is being successfully decoded with fewer errors,
providing more consistent throughput. The BER numbers for both satellites, if
available in your region, are presented in the menu system of the RX 400p. The bit
error rate has a default, no-lock value of 500 or more. As the receiver begins to
successfully acquire the signal, it will result in a lower bit error rate. For best
operation, this value should be less than 150 and ideally less than 20.
Section 4.10.1 provides more information on the display of the BER. A graphical
presentation of the reception quality is provided in the signal tracking bar chart. Refer
to Section 4.7 for further information.
2.3 OmniSTAR Operation
The following sections describe the general operation and performance monitoring of
the OmniSTAR sensor within the RX 400p.
2.3.1 Automatic Tracking
The RX 400p features an Automatic mode that allows the receiver to locate the best
L-band spot beam if more than one is available in a particular region. This function
frees you from having to adjust the frequency of the L-band DGPS receiver. For
flexibility, the OmniSTAR receiver also features a manual tune mode.
2.3.2 Receiver Performance
The internal OmniSTAR receiver provides both a lock icon and a bit error rate to
describe the lock status and reception quality. Both of these features depend on a
line-of-sight between the CDA-2B antenna and the geostationary communications
satellite broadcasting OmniSTAR correction information.