Williamson-Hadamard spreading sequences for DS-CDMA applications
نویسندگان
چکیده
منابع مشابه
Williamson-Hadamard spreading sequences for DS-CDMA applications
Orthogonal bipolar spreading sequences are used in direct sequence code division multiple access (DS-CDMA) systems for both spectrum spreading and channel separation. The most commonly used sequences are Walsh– Hadamard sequences of lengths being an integer power of 2. A construction based on Williamson’s arrays leading to sequences of lengths N:4 (mod 8) is presented in the paper. Aperiodic co...
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We propose a simple but efficient method for modifying Walsh-Hadamard sequences to achieve correlation properties suited for asynchronous DS CDMA applications. The proposed method can be used to minimize the mean square value of aperiodic cross-correlation or the mean square value of aperiodic autocorrelation, the maximum value of aperiodic cross-correlation functions, merit factor or other pro...
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Golay complementary sequences, often referred to as Golay pairs, are characterised by the property that the sum of their aperiodic autocorrelation functions equals to zero, except for the zero shift. Because of this property, Golay complementary sequences can be utilised to construct Hadamard matrices defining sets of orthogonal spreading sequences for DS CDMA systems of the lengths not necessa...
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ژورنال
عنوان ژورنال: Wireless Communications and Mobile Computing
سال: 2003
ISSN: 1530-8669,1530-8677
DOI: 10.1002/wcm.143