Title :
Diversity with distributed decisions combining for direct-sequence CDMA in a shadowed Rician-fading land-mobile satellite channel
Author :
Chau, Yawgeng A. ; Sun, Ji-Ten
Author_Institution :
Dept. of Electr. Eng., Yuan-Ze Inst. of Technol., Chungli, Taiwan
fDate :
5/1/1996 12:00:00 AM
Abstract :
The performance of two diversity schemes with distributed decisions combining is analyzed and compared with that of the selection and maximal ratio-combining schemes for binary-phase shift keying (BPSK) direct-sequence code-division multiple access (DS-CDMA) in a shadowed Rician-fading land-mobile satellite channel. In the first scheme of distributed decisions combining, the combiner collects only the binary branch decisions to make the data decision. In the second scheme, the combiner makes the data decision using the branch decisions and the channel states. Both symmetrical and asymmetrical diversity branches are considered. Based on optimal likelihood ratio testing, a new data decision rule is devised for the detection of the spread-spectrum signals in the DS-CDMA system. Upper bounds are employed for the performance evaluation of the diversity combining schemes when the bit error probability is difficult to compute. Numerical results are presented for the satellite channel under light, average, and heavy shadowing
Keywords :
Rician channels; code division multiple access; distributed decision making; diversity reception; error statistics; fading; land mobile radio; maximum likelihood detection; mobile satellite communication; phase shift keying; pseudonoise codes; spread spectrum communication; BPSK; DS-CDMA; asymmetrical diversity branch; binary branch decisions; binary-phase shift keying; bit error probability; channel states; data decision; data decision rule; detection; direct-sequence CDMA; direct-sequence code-division multiple access; distributed decisions combining; diversity schemes; optimal likelihood ratio testing; performance evaluation; shadowed Rician-fading land-mobile satellite channel; spread-spectrum signals; symmetrical diversity branch; upper bounds; Binary phase shift keying; Direct-sequence code-division multiple access; Diversity reception; Error probability; Multiaccess communication; Performance analysis; Satellites; Spread spectrum communication; System testing; Upper bound;
Journal_Title :
Vehicular Technology, IEEE Transactions on
