Concatenative Complete Complementary Code Division Multiple Access and its Fast Transform
نویسندگان
چکیده
Over multipath channels, complete complementary code division multiple access and convolutional spreading provide inter-channel interference free transmission with an enhanced spectral efficiency. However, the convolutional spreading (CS) operation of systems is computationally complex involves a high peak-to-average power ratio. To address such issues, we propose xmlns:xlink="http://www.w3.org/1999/xlink">concatenative code (CCCC) access, named (CCC-CDMA). Since CCCCs can be generated from rows Walsh-Hadamard or discrete Fourier transform matrices, CS implemented using corresponding fast transforms to reduce computational complexity. Simulation results show that enlargement factor strengthens robustness against clipping noise. The binary CCCC by matrix exhibited excellent Doppler frequency shifts.
منابع مشابه
Code Division Multiple Access
1 CDMA Concept 4 1.1 Basic Principles of Spread Spectrum . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1.1 Direct Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.1.2 Frequency Hopping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.1.3 Time Hopper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.1.4 Hybrid Systems . ....
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ژورنال
عنوان ژورنال: IEEE Transactions on Wireless Communications
سال: 2023
ISSN: ['1536-1276', '1558-2248']
DOI: https://doi.org/10.1109/twc.2023.3250659