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4.2.1 ACQUISITION SEQUENCE The Acquisition Sequence is a data structure forming a preamble which provides for initial
symbol synchronization within the incoming stream of detected symbols. The length of the
Acquisition Sequence shall be selected according to the mission telecommand link
performance requirements but the preferred minimum length is 16 octets. The length is not
required to be an integral multiple of octets. The pattern of the Acquisition Sequence shall
be alternating “ones” and “zeros”, starting with either a “one” or a “zero”.
4.2.2 CLTU The CLTU is the data structure (symbol sequence) furnished from the layer above, and
defined in 3.2.2. It contains the data symbols that are to be transmitted to the spacecraft.
Each codeblock within the CLTU, having the format specified in 3.2.1, provides at least 2
data transitions per codeblock. If the spacecraft symbol synchronization design necessitates
more frequent transitions, either the CLTU as delivered to the physi...
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This document was uploaded on 03/06/2014.
- Spring '14