Method for generating signal of non-interference quasi-synchronous CDMA communication system

A code division multiple access and communication system technology, which is applied in the signal generation field of non-interference quasi-synchronous code division multiple access communication system, and can solve the problems of system capacity limitation, difficulty in system synchronization, and difficulty in ensuring accurate uplink synchronization.

Inactive Publication Date: 2009-01-28
CHONGQING WIRELESS OASIS COMM TECHCO
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Problems solved by technology

For mobile communication systems, it is not easy to ensure accurate synchronization of the uplink. The multipath propagation of the wireless channel makes system synchronization more difficult, and the performance of the synchronous code division multiple access communication system is further reduced due to the existence of the near-far effect. make the system capacity limited

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  • Method for generating signal of non-interference quasi-synchronous CDMA communication system
  • Method for generating signal of non-interference quasi-synchronous CDMA communication system
  • Method for generating signal of non-interference quasi-synchronous CDMA communication system

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Embodiment Construction

[0063] The signal generation method of the interference-free quasi-synchronous code division multiple access communication system of the present invention comprises the following steps:

[0064] From having zero correlation zone length Z CZ Select as the spread code word of the spread code in the spread sequence code group of the spread spectrum;

[0065] performing spread-spectrum modulation processing on the input original data by using the selected spread-spectrum codeword, thereby generating a spread-spectrum modulated signal;

[0066] Wherein, the spreading sequence code group is composed of a Z-complementary sequence set Z-CS (M, 2, N, Z) whose sequence length is N, the number of complementary sequences is 2, the number of companions is M, and the length of the zero-correlation zone is Z. ) and the second-order Walsh-Hadamard orthogonal matrix.

[0067] The generation of the spreading sequence code group with zero correlation region of the present invention will be des...

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Abstract

The invention discloses a method for generating a signal for an interference-free quasi-synchronous CDMA communication system, comprising the following steps: a spectrum spreading sequence encode block is a similarly generalized double displacement orthogonal sequence set generated by a Z-complementation sequence set and an orthogonal sequence set; the number of the sequences and the lengths of the sequences are increased by the operation of the Walsh-Hadamard extension; and a zero related area is realized by the related operations such as removing the odd displacement. When the maximum synchronous error of the system and the maximum multipath delay of the channel are extended within the regulated range, the interference-free transmission is realized. The parameter of the spectrum spreading sequence encode block and the efficiency of the system can be adjusted in real time according to practical factors and to select flexibly. The method lowers the requirement of the CDMA communication system on the power control and the synchronization, and reduces the complexity of realizing the system.

Description

technical field [0001] The invention relates to a direct sequence spread spectrum wireless communication, in particular to a signal generating method of a non-interference quasi-synchronous code division multiple access communication system. Background technique [0002] In order to reduce the interference in the CDMA communication system, a synchronous CDMA communication system is proposed, which uses orthogonal Walsh codes as the spreading sequence code group. For mobile communication systems, it is not easy to ensure accurate synchronization of the uplink. The multipath propagation of the wireless channel makes system synchronization more difficult, and the performance of the synchronous code division multiple access communication system is further reduced due to the existence of the near-far effect. make the system capacity limited. In order to minimize the influence of the near-far effect, complex power control techniques are adopted in practical systems such as IS-95....

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H04B1/707H04L27/26H04J13/00H04B1/7107H04J13/12H04J13/14
Inventor 冯莉芳范平志唐小虎郝莉
Owner CHONGQING WIRELESS OASIS COMM TECHCO
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