|
For Full-Text PDF, please login, if you are a member of IEICE,
or go to Pay Per View on menu list, if you are a nonmember of IEICE.
|
Design of Simplified Coherent QPSK Modem for Frequency Hopping Spread Spectrum
Satoru ISHII Atsushi HOSHIKUKI Ryuji KOHNO
Publication
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Vol.E84-A
No.12
pp.2966-2975 Publication Date: 2001/12/01 Online ISSN:
DOI: Print ISSN: 0916-8508 Type of Manuscript: Special Section PAPER (Special Section on Spread Spectrum Techniques and Applications) Category: Keyword: spread spectrum, symbol synchronization, coherent demodulation, carrier extraction, digital PLL,
Full Text: PDF>>
Summary:
PSK coherent demodulation has difficulty in achieving high speed carrier extraction and symbol synchronization when implementing to slow FH-SS radio system. On the other hand, implementation to FPGA has the requirement of a small gate size to design because of FPGA cost issue. We developed a QPSK coherent demodulation digital modem for FH-SS radio systems using FPGA by solving problems. The designed modem performs symbol synchronization with no carrier extractions, under the limitation of the small gate size requirement. The modem employs shift arithmetic operation and a comb digital BPF to achieve very good synchronization lock-up performance with small gate size. In this paper, the symbol synchronization and the carrier tracking scheme are mainly discussed. Analysis of its performance and stability are also explained. The achievement of its very good performance is presented by experimental measurement.
|
|