Code Division Multiple Access
نویسنده
چکیده
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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.2 Basic Principles of CDMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.2.1 RAKE Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1.2.2 Power Control Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 1.2.3 Spreading Sequences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 1.2.4 Classification of Enhanced CDMA System . . . . . . . . . . . . . . . . . . 18 1.2.5 Comparison of APC, VSG, and MC–CDMA . . . . . . . . . . . . . . . . . 21 1.3 Wireless CDMA Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 1.3.1 Bit Error Probability in CDMA . . . . . . . . . . . . . . . . . . . . . . . . 23 1.3.2 Packet Error Probability in CDMA . . . . . . . . . . . . . . . . . . . . . . 30 1.3.3 Maximum Throughput for CDMA Systems for Packet Services . . . . . . 31
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