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Frame Synchronization Without Attached Sync MarkersWe describe a method to synchronize codeword frames without making use of attached synchronization markers (ASMs). Instead, the synchronizer identifies the code structure present in the received symbols, by operating the decoder for a handful of iterations at each possible symbol offset and forming an appropriate metric. This method is computationally more complex and doesn't perform as well as frame synchronizers that utilize an ASM; nevertheless, the new synchronizer acquires frame synchronization in about two seconds when using a 600 kbps software decoder, and would take about 15 milliseconds on prototype hardware. It also eliminates the need for the ASMs, which is an attractive feature for short uplink codes whose coding gain would be diminished by the overheard of ASM bits. The lack of ASMs also would simplify clock distribution for the AR4JA low-density parity-check (LDPC) codes and adds a small amount to the coding gain as well (up to 0.2 dB).
Document ID
Acquisition Source
Jet Propulsion Laboratory
Document Type
Conference Paper
External Source(s)
Hamkins, Jon
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Date Acquired
May 20, 2015
Publication Date
March 5, 2011
Subject Category
Communications And Radar
Meeting Information
Meeting: 2011 IEEE Aerospace Conference
Location: Big Sky, MT
Country: United States
Start Date: March 5, 2011
End Date: March 12, 2011
Sponsors: Institute of Electrical and Electronics Engineers
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