Mid-tech RX 400p, Руководство пользователя

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RX 400p
98-05044 2-2
R1
The estimated positioning precision is accessible through the menu system of the RX
400p receiver. Although this feature is intended for advanced users, it will provide
the real-time estimates of precision. As the receiver is not able to determine accuracy
with respect to a known location in real time (this is traditionally performed in post-
mission analyses), the precision numbers are relative in nature. More about this
feature is discussed in Section 4.9.1.1.
Satellite acquisition quality is described as a signal to noise ratio (SNR). A higher
SNR is indicative of better quality signal reception. SNR information is provided by
the RX 400p via its menu system on a per channel basis numerically as well as
presenting this information symbolically in a bar chart. More about this feature is
discussed in Sections 4.7 and 4.9.2.
2.2 WAAS Operation
The following sections describe the general operation and performance monitoring of
the WAAS demodulator within the RX 400p.
2.2.1 Automatic Tracking
The WAAS demodulator featured within the RX 400p will automatically scan and
track the WAAS satellite signals. This automatic tracking allows you to focus on
other aspects of receiver operation without the need to tune the receiver.
The WAAS demodulator features two-channel tracking that provides an enhanced
ability to maintain acquisition on a WAAS satellite in regions where more than one
satellite is in view. This redundant tracking approach will result in more consistent
acquisition of a signal when in an area where signal blockage of either satellite is
possible.
2.2.2 Receiver Performance
The performance of the WAAS receiver is described in terms of lock icon and a bit
error rate (BER). WAAS requires a line of sight to the WAAS satellites in order to
acquire the signal.