Orthogonal basis spreading sequence for optimal CDMA
نویسندگان
چکیده
منابع مشابه
CDMA Spreading Sequence Design Project
Computer Engineering supervised the project. CDMA, or Code Division Multiple Access, is a communications method commonly used in wireless applications. This project involves designing the fundamental keys that allow encoding and decoding for CDMA, called spreading sequences. The design problem involved three deliverables. The first, I require a mathematical model of a CDMA channel in order to d...
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In this paper, we present a code-division multiple access (CDMA) system with a spreading factor of N that can accommodate up to mN users, where m 2. The m sets of orthogonal spreading sequences are constructed by overlaying the same N orthogonal Walsh-Hadamard sequences with a set-specific pseudonoise (PN) sequence. Interference between user signals from different sets is cancelled by means of ...
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For various quasisynchronous (QS) CDMA systems such as LAS-CDMA system which emerged recently, in order to reduce or eliminate the multiple access interference and multipath interference, it is required to design a set of spreading sequences which are mutually orthogonal within a designed shift zone, called orthogonal zone. For traditional orthogonal sequences, such as Walsh sequences and ortho...
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ژورنال
عنوان ژورنال: JSIAM Letters
سال: 2016
ISSN: 1883-0609,1883-0617
DOI: 10.14495/jsiaml.8.77